ETH Price: $2,566.82 (+1.93%)

Transaction Decoder

Block:
22544823 at May-23-2025 09:58:59 AM +UTC
Transaction Fee:
0.000496612955346837 ETH $1.27
Gas Used:
196,179 Gas / 2.531427703 Gwei

Emitted Events:

285 DexRouter.SwapOrderId( id=112925 )
286 WETH9.Deposit( dst=DexRouter, wad=7296981565318457 )
287 TetherToken.Transfer( from=UniswapV3Pool, to=Spender, value=19588555 )
288 WETH9.Transfer( src=DexRouter, dst=UniswapV3Pool, wad=7296981565318457 )
289 UniswapV3Pool.Swap( sender=DexRouter, recipient=Spender, amount0=7296981565318457, amount1=-19588555, sqrtPriceX96=4105164881982297394439721, liquidity=301125599017175640, tick=-197367 )
290 DexRouter.OrderRecord( fromToken=0xEeeeeEee...eeeeeEEeE, toToken=[Receiver] TetherToken, sender=[Sender] 0x95958eb2e25825b71fd4145e62ea57413aa019d5, fromAmount=7296981565318457, returnAmount=19588555 )
291 TetherToken.Transfer( from=Spender, to=[Sender] 0x95958eb2e25825b71fd4145e62ea57413aa019d5, value=19588555 )
292 MetaSwap.Swap( 0xbeee1e6e7fe307ddcf84b0a16137a4430ad5e2480fc4f4a8e250ab56ccd7630d, 0xd6b6d5e0aacce0469a313983d889ed10d0bb7c9545af0285a19b4ff094b4041d, 0x00000000000000000000000095958eb2e25825b71fd4145e62ea57413aa019d5 )

Account State Difference:

  Address   Before After State Difference Code
(beaverbuild)
19.989109956403568501 Eth19.98930613540376468 Eth0.000196179000196179
0x95958eb2...13aA019d5
0.0081 Eth
Nonce: 0
0.000241993283928364 Eth
Nonce: 1
0.007858006716071636
0xC02aaA39...83C756Cc2 2,786,139.577538729896311752 Eth2,786,139.584835711461630209 Eth0.007296981565318457
0xc7bBeC68...9bA1b0e9b
(Uniswap V3: USDT 9)
0xdAC17F95...13D831ec7
0xe3478b0B...948Be1964 419.491738059936608873 Eth419.491802472132015215 Eth0.000064412195406342

Execution Trace

ETH 0.007361393760724799 MetaSwap.swap( aggregatorId=okx, tokenFrom=0x0000000000000000000000000000000000000000, amount=7361393760724799, data=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
  • ETH 0.007361393760724799 Spender.swap( adapter=0xa65Ed75603BeA45f821CEefE02D999AD99D2AfCA, data=0x92F5F03700000000000000000000000095958EB2E25825B71FD4145E62EA57413AA019D50000000000000000000000000000000000000000000000000000000000000000000000000000000000000000DAC17F958D2EE523A2206206994597C13D831EC70000000000000000000000000000000000000000000000000019EC90EA222539000000000000000000000000000000000000000000000000000000000124EB70000000000000000000000000000000000000000000000000000000000000012000000000000000000000000000000000000000000000000000003A952206C206000000000000000000000000E3478B0BB1A5084567C319096437924948BE1964000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000C40D5F0E3B00000000000000000001B91D74DE5D4FCBF63E00296FD95D33236B97940166310000000000000000000000000000000000000000000000000019EC90EA222539000000000000000000000000000000000000000000000000000000000124EB6F00000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000001000000000000000000000000C7BBEC68D12A0D1830360F8EC58FA599BA1B0E9B00000000000000000000000000000000000000000000000000000000 )
    • ETH 0.007361393760724799 0xa65ed75603bea45f821ceefe02d999ad99d2afca.92f5f037( )
      • ETH 0.007296981565318457 DexRouter.uniswapV3SwapTo( receiver=165040739597415657687820409033874011404928872077157937, amount=7296981565318457, minReturn=19196783, pools=[1140279996912942340220498878376233146590653255323] ) => ( returnAmount=19588555 )
        • ETH 0.007296981565318457 WETH9.CALL( )
        • UniswapV3Pool.swap( recipient=0x74de5d4FCbf63E00296fd95d33236B9794016631, zeroForOne=True, amountSpecified=7296981565318457, sqrtPriceLimitX96=4295128740, data=0x0000000000000000000000007D0CCAA3FAC1E5A943C5168B6CED828691B46B36 ) => ( amount0=7296981565318457, amount1=-19588555 )
          • TetherToken.transfer( _to=0x74de5d4FCbf63E00296fd95d33236B9794016631, _value=19588555 )
          • WETH9.balanceOf( 0xc7bBeC68d12a0d1830360F8Ec58fA599bA1b0e9b ) => ( 714675008318776115007 )
          • DexRouter.uniswapV3SwapCallback( amount0Delta=7296981565318457, amount1Delta=-19588555, 0x0000000000000000000000007D0CCAA3FAC1E5A943C5168B6CED828691B46B36 )
            • UniswapV3Pool.STATICCALL( )
            • UniswapV3Pool.STATICCALL( )
            • UniswapV3Pool.STATICCALL( )
            • WETH9.transfer( dst=0xc7bBeC68d12a0d1830360F8Ec58fA599bA1b0e9b, wad=7296981565318457 ) => ( True )
            • WETH9.balanceOf( 0xc7bBeC68d12a0d1830360F8Ec58fA599bA1b0e9b ) => ( 714682305300341433464 )
            • UniswapV3Pool.STATICCALL( )
            • ETH 0.000064412195406342 0xe3478b0bb1a5084567c319096437924948be1964.CALL( )
            • TetherToken.balanceOf( who=0x74de5d4FCbf63E00296fd95d33236B9794016631 ) => ( 19588555 )
            • TetherToken.transfer( _to=0x95958eb2E25825B71FD4145E62EA57413aA019d5, _value=19588555 )
              File 1 of 6: MetaSwap
              pragma solidity ^0.6.0;
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
              import "@openzeppelin/contracts/utils/Address.sol";
              import "../Constants.sol";
              contract CommonAdapter {
                  using SafeERC20 for IERC20;
                  using Address for address;
                  using Address for address payable;
                  /**
                   * @dev Performs a swap
                   * @param recipient The original msg.sender performing the swap
                   * @param aggregator Address of the aggregator's contract
                   * @param spender Address to which tokens will be approved
                   * @param method Selector of the function to be called in the aggregator's contract
                   * @param tokenFrom Token to be swapped
                   * @param tokenTo Token to be received
                   * @param amountFrom Amount of tokenFrom to swap
                   * @param amountTo Minimum amount of tokenTo to receive
                   * @param data Data used for the call made to the aggregator's contract
                   */
                  function swap(
                      address payable recipient,
                      address aggregator,
                      address spender,
                      bytes4 method,
                      IERC20 tokenFrom,
                      IERC20 tokenTo,
                      uint256 amountFrom,
                      uint256 amountTo,
                      bytes calldata data
                  ) external payable {
                      require(tokenFrom != tokenTo, "TOKEN_PAIR_INVALID");
                      if (address(tokenFrom) != Constants.ETH) {
                          _approveSpender(tokenFrom, spender, amountFrom);
                      }
                      // We always forward msg.value as it may be necessary to pay fees
                      bytes memory encodedData = abi.encodePacked(method, data);
                      aggregator.functionCallWithValue(encodedData, msg.value);
                      // Transfer remaining balance of tokenFrom to sender
                      if (address(tokenFrom) != Constants.ETH) {
                          uint256 balance = tokenFrom.balanceOf(address(this));
                          _transfer(tokenFrom, balance, recipient);
                      }
                      uint256 weiBalance = address(this).balance;
                      // Transfer remaining balance of tokenTo to sender
                      if (address(tokenTo) != Constants.ETH) {
                          uint256 balance = tokenTo.balanceOf(address(this));
                          require(balance >= amountTo, "INSUFFICIENT_AMOUNT");
                          _transfer(tokenTo, balance, recipient);
                      } else {
                          // If tokenTo == ETH, then check that the remaining ETH balance >= amountTo
                          require(weiBalance >= amountTo, "INSUFFICIENT_AMOUNT");
                      }
                      // If there are unused fees or if tokenTo is ETH, transfer to sender
                      if (weiBalance > 0) {
                          recipient.sendValue(weiBalance);
                      }
                  }
                  /**
                   * @dev Transfers token to sender if amount > 0
                   * @param token IERC20 token to transfer to sender
                   * @param amount Amount of token to transfer
                   * @param recipient Address that will receive the tokens
                   */
                  function _transfer(
                      IERC20 token,
                      uint256 amount,
                      address recipient
                  ) internal {
                      if (amount > 0) {
                          token.safeTransfer(recipient, amount);
                      }
                  }
                  // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/SafeERC20.sol
                  /**
                   * @dev Approves max amount of token to the spender if the allowance is lower than amount
                   * @param token The ERC20 token to approve
                   * @param spender Address to which funds will be approved
                   * @param amount Amount used to compare current allowance
                   */
                  function _approveSpender(
                      IERC20 token,
                      address spender,
                      uint256 amount
                  ) internal {
                      // If allowance is not enough, approve max possible amount
                      uint256 allowance = token.allowance(address(this), spender);
                      if (allowance < amount) {
                          bytes memory returndata = address(token).functionCall(
                              abi.encodeWithSelector(
                                  token.approve.selector,
                                  spender,
                                  type(uint256).max
                              )
                          );
                          if (returndata.length > 0) {
                              // Return data is optional
                              require(abi.decode(returndata, (bool)), "APPROVAL_FAILED");
                          }
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.6.0;
              /**
               * @dev Interface of the ERC20 standard as defined in the EIP.
               */
              interface IERC20 {
                  /**
                   * @dev Returns the amount of tokens in existence.
                   */
                  function totalSupply() external view returns (uint256);
                  /**
                   * @dev Returns the amount of tokens owned by `account`.
                   */
                  function balanceOf(address account) external view returns (uint256);
                  /**
                   * @dev Moves `amount` tokens from the caller's account to `recipient`.
                   *
                   * Returns a boolean value indicating whether the operation succeeded.
                   *
                   * Emits a {Transfer} event.
                   */
                  function transfer(address recipient, uint256 amount) external returns (bool);
                  /**
                   * @dev Returns the remaining number of tokens that `spender` will be
                   * allowed to spend on behalf of `owner` through {transferFrom}. This is
                   * zero by default.
                   *
                   * This value changes when {approve} or {transferFrom} are called.
                   */
                  function allowance(address owner, address spender) external view returns (uint256);
                  /**
                   * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
                   *
                   * Returns a boolean value indicating whether the operation succeeded.
                   *
                   * IMPORTANT: Beware that changing an allowance with this method brings the risk
                   * that someone may use both the old and the new allowance by unfortunate
                   * transaction ordering. One possible solution to mitigate this race
                   * condition is to first reduce the spender's allowance to 0 and set the
                   * desired value afterwards:
                   * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                   *
                   * Emits an {Approval} event.
                   */
                  function approve(address spender, uint256 amount) external returns (bool);
                  /**
                   * @dev Moves `amount` tokens from `sender` to `recipient` using the
                   * allowance mechanism. `amount` is then deducted from the caller's
                   * allowance.
                   *
                   * Returns a boolean value indicating whether the operation succeeded.
                   *
                   * Emits a {Transfer} event.
                   */
                  function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
                  /**
                   * @dev Emitted when `value` tokens are moved from one account (`from`) to
                   * another (`to`).
                   *
                   * Note that `value` may be zero.
                   */
                  event Transfer(address indexed from, address indexed to, uint256 value);
                  /**
                   * @dev Emitted when the allowance of a `spender` for an `owner` is set by
                   * a call to {approve}. `value` is the new allowance.
                   */
                  event Approval(address indexed owner, address indexed spender, uint256 value);
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.6.0;
              import "./IERC20.sol";
              import "../../math/SafeMath.sol";
              import "../../utils/Address.sol";
              /**
               * @title SafeERC20
               * @dev Wrappers around ERC20 operations that throw on failure (when the token
               * contract returns false). Tokens that return no value (and instead revert or
               * throw on failure) are also supported, non-reverting calls are assumed to be
               * successful.
               * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
               * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
               */
              library SafeERC20 {
                  using SafeMath for uint256;
                  using Address for address;
                  function safeTransfer(IERC20 token, address to, uint256 value) internal {
                      _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
                  }
                  function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
                      _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
                  }
                  /**
                   * @dev Deprecated. This function has issues similar to the ones found in
                   * {IERC20-approve}, and its usage is discouraged.
                   *
                   * Whenever possible, use {safeIncreaseAllowance} and
                   * {safeDecreaseAllowance} instead.
                   */
                  function safeApprove(IERC20 token, address spender, uint256 value) internal {
                      // safeApprove should only be called when setting an initial allowance,
                      // or when resetting it to zero. To increase and decrease it, use
                      // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
                      // solhint-disable-next-line max-line-length
                      require((value == 0) || (token.allowance(address(this), spender) == 0),
                          "SafeERC20: approve from non-zero to non-zero allowance"
                      );
                      _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
                  }
                  function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                      uint256 newAllowance = token.allowance(address(this), spender).add(value);
                      _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                  }
                  function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                      uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
                      _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                  }
                  /**
                   * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
                   * on the return value: the return value is optional (but if data is returned, it must not be false).
                   * @param token The token targeted by the call.
                   * @param data The call data (encoded using abi.encode or one of its variants).
                   */
                  function _callOptionalReturn(IERC20 token, bytes memory data) private {
                      // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
                      // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
                      // the target address contains contract code and also asserts for success in the low-level call.
                      bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
                      if (returndata.length > 0) { // Return data is optional
                          // solhint-disable-next-line max-line-length
                          require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.6.0;
              /**
               * @dev Wrappers over Solidity's arithmetic operations with added overflow
               * checks.
               *
               * Arithmetic operations in Solidity wrap on overflow. This can easily result
               * in bugs, because programmers usually assume that an overflow raises an
               * error, which is the standard behavior in high level programming languages.
               * `SafeMath` restores this intuition by reverting the transaction when an
               * operation overflows.
               *
               * Using this library instead of the unchecked operations eliminates an entire
               * class of bugs, so it's recommended to use it always.
               */
              library SafeMath {
                  /**
                   * @dev Returns the addition of two unsigned integers, reverting on
                   * overflow.
                   *
                   * Counterpart to Solidity's `+` operator.
                   *
                   * Requirements:
                   *
                   * - Addition cannot overflow.
                   */
                  function add(uint256 a, uint256 b) internal pure returns (uint256) {
                      uint256 c = a + b;
                      require(c >= a, "SafeMath: addition overflow");
                      return c;
                  }
                  /**
                   * @dev Returns the subtraction of two unsigned integers, reverting on
                   * overflow (when the result is negative).
                   *
                   * Counterpart to Solidity's `-` operator.
                   *
                   * Requirements:
                   *
                   * - Subtraction cannot overflow.
                   */
                  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                      return sub(a, b, "SafeMath: subtraction overflow");
                  }
                  /**
                   * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
                   * overflow (when the result is negative).
                   *
                   * Counterpart to Solidity's `-` operator.
                   *
                   * Requirements:
                   *
                   * - Subtraction cannot overflow.
                   */
                  function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                      require(b <= a, errorMessage);
                      uint256 c = a - b;
                      return c;
                  }
                  /**
                   * @dev Returns the multiplication of two unsigned integers, reverting on
                   * overflow.
                   *
                   * Counterpart to Solidity's `*` operator.
                   *
                   * Requirements:
                   *
                   * - Multiplication cannot overflow.
                   */
                  function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                      // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                      // benefit is lost if 'b' is also tested.
                      // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                      if (a == 0) {
                          return 0;
                      }
                      uint256 c = a * b;
                      require(c / a == b, "SafeMath: multiplication overflow");
                      return c;
                  }
                  /**
                   * @dev Returns the integer division of two unsigned integers. Reverts on
                   * division by zero. The result is rounded towards zero.
                   *
                   * Counterpart to Solidity's `/` operator. Note: this function uses a
                   * `revert` opcode (which leaves remaining gas untouched) while Solidity
                   * uses an invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function div(uint256 a, uint256 b) internal pure returns (uint256) {
                      return div(a, b, "SafeMath: division by zero");
                  }
                  /**
                   * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
                   * division by zero. The result is rounded towards zero.
                   *
                   * Counterpart to Solidity's `/` operator. Note: this function uses a
                   * `revert` opcode (which leaves remaining gas untouched) while Solidity
                   * uses an invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                      require(b > 0, errorMessage);
                      uint256 c = a / b;
                      // assert(a == b * c + a % b); // There is no case in which this doesn't hold
                      return c;
                  }
                  /**
                   * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                   * Reverts when dividing by zero.
                   *
                   * Counterpart to Solidity's `%` operator. This function uses a `revert`
                   * opcode (which leaves remaining gas untouched) while Solidity uses an
                   * invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function mod(uint256 a, uint256 b) internal pure returns (uint256) {
                      return mod(a, b, "SafeMath: modulo by zero");
                  }
                  /**
                   * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                   * Reverts with custom message when dividing by zero.
                   *
                   * Counterpart to Solidity's `%` operator. This function uses a `revert`
                   * opcode (which leaves remaining gas untouched) while Solidity uses an
                   * invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                      require(b != 0, errorMessage);
                      return a % b;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.6.2;
              /**
               * @dev Collection of functions related to the address type
               */
              library Address {
                  /**
                   * @dev Returns true if `account` is a contract.
                   *
                   * [IMPORTANT]
                   * ====
                   * It is unsafe to assume that an address for which this function returns
                   * false is an externally-owned account (EOA) and not a contract.
                   *
                   * Among others, `isContract` will return false for the following
                   * types of addresses:
                   *
                   *  - an externally-owned account
                   *  - a contract in construction
                   *  - an address where a contract will be created
                   *  - an address where a contract lived, but was destroyed
                   * ====
                   */
                  function isContract(address account) internal view returns (bool) {
                      // This method relies in extcodesize, which returns 0 for contracts in
                      // construction, since the code is only stored at the end of the
                      // constructor execution.
                      uint256 size;
                      // solhint-disable-next-line no-inline-assembly
                      assembly { size := extcodesize(account) }
                      return size > 0;
                  }
                  /**
                   * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                   * `recipient`, forwarding all available gas and reverting on errors.
                   *
                   * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                   * of certain opcodes, possibly making contracts go over the 2300 gas limit
                   * imposed by `transfer`, making them unable to receive funds via
                   * `transfer`. {sendValue} removes this limitation.
                   *
                   * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                   *
                   * IMPORTANT: because control is transferred to `recipient`, care must be
                   * taken to not create reentrancy vulnerabilities. Consider using
                   * {ReentrancyGuard} or the
                   * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                   */
                  function sendValue(address payable recipient, uint256 amount) internal {
                      require(address(this).balance >= amount, "Address: insufficient balance");
                      // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                      (bool success, ) = recipient.call{ value: amount }("");
                      require(success, "Address: unable to send value, recipient may have reverted");
                  }
                  /**
                   * @dev Performs a Solidity function call using a low level `call`. A
                   * plain`call` is an unsafe replacement for a function call: use this
                   * function instead.
                   *
                   * If `target` reverts with a revert reason, it is bubbled up by this
                   * function (like regular Solidity function calls).
                   *
                   * Returns the raw returned data. To convert to the expected return value,
                   * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                   *
                   * Requirements:
                   *
                   * - `target` must be a contract.
                   * - calling `target` with `data` must not revert.
                   *
                   * _Available since v3.1._
                   */
                  function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                    return functionCall(target, data, "Address: low-level call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                   * `errorMessage` as a fallback revert reason when `target` reverts.
                   *
                   * _Available since v3.1._
                   */
                  function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                      return _functionCallWithValue(target, data, 0, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but also transferring `value` wei to `target`.
                   *
                   * Requirements:
                   *
                   * - the calling contract must have an ETH balance of at least `value`.
                   * - the called Solidity function must be `payable`.
                   *
                   * _Available since v3.1._
                   */
                  function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
                      return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                   * with `errorMessage` as a fallback revert reason when `target` reverts.
                   *
                   * _Available since v3.1._
                   */
                  function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
                      require(address(this).balance >= value, "Address: insufficient balance for call");
                      return _functionCallWithValue(target, data, value, errorMessage);
                  }
                  function _functionCallWithValue(address target, bytes memory data, uint256 weiValue, string memory errorMessage) private returns (bytes memory) {
                      require(isContract(target), "Address: call to non-contract");
                      // solhint-disable-next-line avoid-low-level-calls
                      (bool success, bytes memory returndata) = target.call{ value: weiValue }(data);
                      if (success) {
                          return returndata;
                      } else {
                          // Look for revert reason and bubble it up if present
                          if (returndata.length > 0) {
                              // The easiest way to bubble the revert reason is using memory via assembly
                              // solhint-disable-next-line no-inline-assembly
                              assembly {
                                  let returndata_size := mload(returndata)
                                  revert(add(32, returndata), returndata_size)
                              }
                          } else {
                              revert(errorMessage);
                          }
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.6.0;
              library Constants {
                  address internal constant ETH = 0x0000000000000000000000000000000000000000;
              }
              pragma solidity ^0.6.0;
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
              import "@openzeppelin/contracts/math/SafeMath.sol";
              import "@openzeppelin/contracts/utils/Address.sol";
              import "../Constants.sol";
              contract FeeCommonAdapter {
                  using SafeERC20 for IERC20;
                  using Address for address;
                  using Address for address payable;
                  using SafeMath for uint256;
                  // solhint-disable-next-line var-name-mixedcase
                  address payable public immutable FEE_WALLET;
                  constructor(address payable feeWallet) public {
                      FEE_WALLET = feeWallet;
                  }
                  /**
                   * @dev Performs a swap
                   * @param recipient The original msg.sender performing the swap
                   * @param aggregator Address of the aggregator's contract
                   * @param spender Address to which tokens will be approved
                   * @param method Selector of the function to be called in the aggregator's contract
                   * @param tokenFrom Token to be swapped
                   * @param tokenTo Token to be received
                   * @param amountFrom Amount of tokenFrom to swap
                   * @param amountTo Minimum amount of tokenTo to receive
                   * @param data Data used for the call made to the aggregator's contract
                   * @param fee Amount of tokenFrom sent to the fee wallet
                   */
                  function swap(
                      address payable recipient,
                      address aggregator,
                      address spender,
                      bytes4 method,
                      IERC20 tokenFrom,
                      IERC20 tokenTo,
                      uint256 amountFrom,
                      uint256 amountTo,
                      bytes calldata data,
                      uint256 fee
                  ) external payable {
                      require(tokenFrom != tokenTo, "TOKEN_PAIR_INVALID");
                      if (address(tokenFrom) == Constants.ETH) {
                          FEE_WALLET.sendValue(fee);
                      } else {
                          _transfer(tokenFrom, fee, FEE_WALLET);
                          _approveSpender(tokenFrom, spender, amountFrom);
                      }
                      // We always forward msg.value as it may be necessary to pay fees
                      aggregator.functionCallWithValue(
                          abi.encodePacked(method, data),
                          address(this).balance
                      );
                      // Transfer remaining balance of tokenFrom to sender
                      if (address(tokenFrom) != Constants.ETH) {
                          _transfer(tokenFrom, tokenFrom.balanceOf(address(this)), recipient);
                      }
                      uint256 weiBalance = address(this).balance;
                      // Transfer remaining balance of tokenTo to sender
                      if (address(tokenTo) != Constants.ETH) {
                          uint256 balance = tokenTo.balanceOf(address(this));
                          require(balance >= amountTo, "INSUFFICIENT_AMOUNT");
                          _transfer(tokenTo, balance, recipient);
                      } else {
                          // If tokenTo == ETH, then check that the remaining ETH balance >= amountTo
                          require(weiBalance >= amountTo, "INSUFFICIENT_AMOUNT");
                      }
                      // If there are unused fees or if tokenTo is ETH, transfer to sender
                      if (weiBalance > 0) {
                          recipient.sendValue(weiBalance);
                      }
                  }
                  /**
                   * @dev Transfers token to sender if amount > 0
                   * @param token IERC20 token to transfer to sender
                   * @param amount Amount of token to transfer
                   * @param recipient Address that will receive the tokens
                   */
                  function _transfer(
                      IERC20 token,
                      uint256 amount,
                      address recipient
                  ) internal {
                      if (amount > 0) {
                          token.safeTransfer(recipient, amount);
                      }
                  }
                  // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/SafeERC20.sol
                  /**
                   * @dev Approves max amount of token to the spender if the allowance is lower than amount
                   * @param token The ERC20 token to approve
                   * @param spender Address to which funds will be approved
                   * @param amount Amount used to compare current allowance
                   */
                  function _approveSpender(
                      IERC20 token,
                      address spender,
                      uint256 amount
                  ) internal {
                      // If allowance is not enough, approve max possible amount
                      uint256 allowance = token.allowance(address(this), spender);
                      if (allowance < amount) {
                          bytes memory returndata = address(token).functionCall(
                              abi.encodeWithSelector(
                                  token.approve.selector,
                                  spender,
                                  type(uint256).max
                              )
                          );
                          if (returndata.length > 0) {
                              // Return data is optional
                              require(abi.decode(returndata, (bool)), "APPROVAL_FAILED");
                          }
                      }
                  }
              }
              pragma solidity ^0.6.0;
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
              import "@openzeppelin/contracts/math/SafeMath.sol";
              import "@openzeppelin/contracts/utils/Address.sol";
              import "../Constants.sol";
              import "../IWETH.sol";
              contract FeeWethAdapter {
                  using SafeERC20 for IERC20;
                  using Address for address;
                  using Address for address payable;
                  using SafeMath for uint256;
                  IWETH public immutable weth;
                  // solhint-disable-next-line var-name-mixedcase
                  address payable public immutable FEE_WALLET;
                  constructor(IWETH _weth, address payable feeWallet) public {
                      weth = _weth;
                      FEE_WALLET = feeWallet;
                  }
                  /**
                   * @dev Performs a swap
                   * @param recipient The original msg.sender performing the swap
                   * @param aggregator Address of the aggregator's contract
                   * @param spender Address to which tokens will be approved
                   * @param method Selector of the function to be called in the aggregator's contract
                   * @param tokenFrom Token to be swapped
                   * @param tokenTo Token to be received
                   * @param amountFrom Amount of tokenFrom to swap
                   * @param amountTo Minimum amount of tokenTo to receive
                   * @param data Data used for the call made to the aggregator's contract
                   * @param fee Amount of tokenFrom sent to the fee wallet
                   */
                  function swap(
                      address payable recipient,
                      address aggregator,
                      address spender,
                      bytes4 method,
                      IERC20 tokenFrom,
                      IERC20 tokenTo,
                      uint256 amountFrom,
                      uint256 amountTo,
                      bytes calldata data,
                      uint256 fee
                  ) external payable {
                      require(tokenFrom != tokenTo, "TOKEN_PAIR_INVALID");
                      if (address(tokenFrom) == Constants.ETH) {
                          FEE_WALLET.sendValue(fee);
                          // If tokenFrom is ETH, msg.value = fee + amountFrom (total fee could be 0)
                          // Can't deal with ETH, convert to WETH, the remaining balance will be the fee
                          weth.deposit{value: amountFrom}();
                          _approveSpender(weth, spender, amountFrom);
                      } else {
                          _transfer(tokenFrom, fee, FEE_WALLET);
                          // Otherwise capture tokens from sender
                          _approveSpender(tokenFrom, spender, amountFrom);
                      }
                      // Perform the swap
                      aggregator.functionCallWithValue(
                          abi.encodePacked(method, data),
                          address(this).balance
                      );
                      // Transfer remaining balance of tokenFrom to sender
                      if (address(tokenFrom) != Constants.ETH) {
                          _transfer(tokenFrom, tokenFrom.balanceOf(address(this)), recipient);
                      } else {
                          // If using ETH, just unwrap any remaining WETH
                          // At the end of this function all ETH will be transferred to the sender
                          _unwrapWETH();
                      }
                      uint256 weiBalance = address(this).balance;
                      // Transfer remaining balance of tokenTo to sender
                      if (address(tokenTo) != Constants.ETH) {
                          uint256 balance = tokenTo.balanceOf(address(this));
                          require(balance >= amountTo, "INSUFFICIENT_AMOUNT");
                          _transfer(tokenTo, balance, recipient);
                      } else {
                          // If tokenTo == ETH, unwrap received WETH and add it to the wei balance,
                          // then check that the remaining ETH balance >= amountTo
                          // It is safe to not use safeMath as no one can have enough Ether to overflow
                          weiBalance += _unwrapWETH();
                          require(weiBalance >= amountTo, "INSUFFICIENT_AMOUNT");
                      }
                      // If there are unused fees or if tokenTo is ETH, transfer to sender
                      if (weiBalance > 0) {
                          recipient.sendValue(weiBalance);
                      }
                  }
                  /**
                   * @dev Unwraps all available WETH into ETH
                   */
                  function _unwrapWETH() internal returns (uint256) {
                      uint256 balance = weth.balanceOf(address(this));
                      weth.withdraw(balance);
                      return balance;
                  }
                  /**
                   * @dev Transfers token to sender if amount > 0
                   * @param token IERC20 token to transfer to sender
                   * @param amount Amount of token to transfer
                   * @param recipient Address that will receive the tokens
                   */
                  function _transfer(
                      IERC20 token,
                      uint256 amount,
                      address recipient
                  ) internal {
                      if (amount > 0) {
                          token.safeTransfer(recipient, amount);
                      }
                  }
                  // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/SafeERC20.sol
                  /**
                   * @dev Approves max amount of token to the spender if the allowance is lower than amount
                   * @param token The ERC20 token to approve
                   * @param spender Address to which funds will be approved
                   * @param amount Amount used to compare current allowance
                   */
                  function _approveSpender(
                      IERC20 token,
                      address spender,
                      uint256 amount
                  ) internal {
                      // If allowance is not enough, approve max possible amount
                      uint256 allowance = token.allowance(address(this), spender);
                      if (allowance < amount) {
                          bytes memory returndata = address(token).functionCall(
                              abi.encodeWithSelector(
                                  token.approve.selector,
                                  spender,
                                  type(uint256).max
                              )
                          );
                          if (returndata.length > 0) {
                              // Return data is optional
                              require(abi.decode(returndata, (bool)), "APPROVAL_FAILED");
                          }
                      }
                  }
              }
              pragma solidity ^0.6.0;
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              interface IWETH is IERC20 {
                  function deposit() external payable;
                  function withdraw(uint256) external;
              }
              pragma solidity ^0.6.0;
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
              import "@openzeppelin/contracts/math/SafeMath.sol";
              import "@openzeppelin/contracts/utils/Address.sol";
              import "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol";
              import "../Constants.sol";
              contract UniswapAdapter {
                  using SafeERC20 for IERC20;
                  using Address for address;
                  using Address for address payable;
                  using SafeMath for uint256;
                  // solhint-disable-next-line var-name-mixedcase
                  IUniswapV2Router02 public immutable UNISWAP;
                  // solhint-disable-next-line var-name-mixedcase
                  address payable public immutable FEE_WALLET;
                  constructor(address payable feeWallet, IUniswapV2Router02 uniswap) public {
                      FEE_WALLET = feeWallet;
                      UNISWAP = uniswap;
                  }
                  /**
                   * @dev Performs a swap
                   * @param recipient The original msg.sender performing the swap
                   * @param tokenFrom Token to be swapped
                   * @param tokenTo Token to be received
                   * @param amountFrom Amount of tokenFrom to swap
                   * @param amountTo Minimum amount of tokenTo to receive
                   * @param path Used by Uniswap
                   * @param deadline Timestamp at which the swap becomes invalid. Used by Uniswap
                   * @param feeOnTransfer Use `supportingFeeOnTransfer` Uniswap methods
                   * @param fee Amount of tokenFrom sent to the fee wallet
                   */
                  function swap(
                      address payable recipient,
                      IERC20 tokenFrom,
                      IERC20 tokenTo,
                      uint256 amountFrom,
                      uint256 amountTo,
                      address[] calldata path,
                      uint256 deadline,
                      bool feeOnTransfer,
                      uint256 fee
                  ) external payable {
                      require(tokenFrom != tokenTo, "TOKEN_PAIR_INVALID");
                      if (address(tokenFrom) == Constants.ETH) {
                          FEE_WALLET.sendValue(fee);
                      } else {
                          _transfer(tokenFrom, fee, FEE_WALLET);
                      }
                      if (address(tokenFrom) == Constants.ETH) {
                          if (feeOnTransfer) {
                              UNISWAP.swapExactETHForTokensSupportingFeeOnTransferTokens{
                                  value: address(this).balance
                              }(amountTo, path, address(this), deadline);
                          } else {
                              UNISWAP.swapExactETHForTokens{value: address(this).balance}(
                                  amountTo,
                                  path,
                                  address(this),
                                  deadline
                              );
                          }
                      } else {
                          _approveSpender(tokenFrom, address(UNISWAP), amountFrom);
                          if (address(tokenTo) == Constants.ETH) {
                              if (feeOnTransfer) {
                                  UNISWAP.swapExactTokensForETHSupportingFeeOnTransferTokens(
                                      amountFrom,
                                      amountTo,
                                      path,
                                      address(this),
                                      deadline
                                  );
                              } else {
                                  UNISWAP.swapExactTokensForETH(
                                      amountFrom,
                                      amountTo,
                                      path,
                                      address(this),
                                      deadline
                                  );
                              }
                          } else {
                              if (feeOnTransfer) {
                                  UNISWAP
                                      .swapExactTokensForTokensSupportingFeeOnTransferTokens(
                                      amountFrom,
                                      amountTo,
                                      path,
                                      address(this),
                                      deadline
                                  );
                              } else {
                                  UNISWAP.swapExactTokensForTokens(
                                      amountFrom,
                                      amountTo,
                                      path,
                                      address(this),
                                      deadline
                                  );
                              }
                          }
                      }
                      // Transfer remaining balance of tokenFrom to sender
                      if (address(tokenFrom) != Constants.ETH) {
                          _transfer(tokenFrom, tokenFrom.balanceOf(address(this)), recipient);
                      }
                      uint256 weiBalance = address(this).balance;
                      // Transfer remaining balance of tokenTo to sender
                      if (address(tokenTo) != Constants.ETH) {
                          uint256 balance = tokenTo.balanceOf(address(this));
                          require(balance >= amountTo, "INSUFFICIENT_AMOUNT");
                          _transfer(tokenTo, balance, recipient);
                      } else {
                          // If tokenTo == ETH, then check that the remaining ETH balance >= amountTo
                          require(weiBalance >= amountTo, "INSUFFICIENT_AMOUNT");
                      }
                      // If there are unused fees or if tokenTo is ETH, transfer to sender
                      if (weiBalance > 0) {
                          recipient.sendValue(weiBalance);
                      }
                  }
                  /**
                   * @dev Transfers token to sender if amount > 0
                   * @param token IERC20 token to transfer to sender
                   * @param amount Amount of token to transfer
                   * @param recipient Address that will receive the tokens
                   */
                  function _transfer(
                      IERC20 token,
                      uint256 amount,
                      address recipient
                  ) internal {
                      if (amount > 0) {
                          token.safeTransfer(recipient, amount);
                      }
                  }
                  // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/SafeERC20.sol
                  /**
                   * @dev Approves max amount of token to the spender if the allowance is lower than amount
                   * @param token The ERC20 token to approve
                   * @param spender Address to which funds will be approved
                   * @param amount Amount used to compare current allowance
                   */
                  function _approveSpender(
                      IERC20 token,
                      address spender,
                      uint256 amount
                  ) internal {
                      // If allowance is not enough, approve max possible amount
                      uint256 allowance = token.allowance(address(this), spender);
                      if (allowance < amount) {
                          bytes memory returndata = address(token).functionCall(
                              abi.encodeWithSelector(
                                  token.approve.selector,
                                  spender,
                                  type(uint256).max
                              )
                          );
                          if (returndata.length > 0) {
                              // Return data is optional
                              require(abi.decode(returndata, (bool)), "APPROVAL_FAILED");
                          }
                      }
                  }
              }
              pragma solidity >=0.6.2;
              import './IUniswapV2Router01.sol';
              interface IUniswapV2Router02 is IUniswapV2Router01 {
                  function removeLiquidityETHSupportingFeeOnTransferTokens(
                      address token,
                      uint liquidity,
                      uint amountTokenMin,
                      uint amountETHMin,
                      address to,
                      uint deadline
                  ) external returns (uint amountETH);
                  function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
                      address token,
                      uint liquidity,
                      uint amountTokenMin,
                      uint amountETHMin,
                      address to,
                      uint deadline,
                      bool approveMax, uint8 v, bytes32 r, bytes32 s
                  ) external returns (uint amountETH);
                  function swapExactTokensForTokensSupportingFeeOnTransferTokens(
                      uint amountIn,
                      uint amountOutMin,
                      address[] calldata path,
                      address to,
                      uint deadline
                  ) external;
                  function swapExactETHForTokensSupportingFeeOnTransferTokens(
                      uint amountOutMin,
                      address[] calldata path,
                      address to,
                      uint deadline
                  ) external payable;
                  function swapExactTokensForETHSupportingFeeOnTransferTokens(
                      uint amountIn,
                      uint amountOutMin,
                      address[] calldata path,
                      address to,
                      uint deadline
                  ) external;
              }
              pragma solidity >=0.6.2;
              interface IUniswapV2Router01 {
                  function factory() external pure returns (address);
                  function WETH() external pure returns (address);
                  function addLiquidity(
                      address tokenA,
                      address tokenB,
                      uint amountADesired,
                      uint amountBDesired,
                      uint amountAMin,
                      uint amountBMin,
                      address to,
                      uint deadline
                  ) external returns (uint amountA, uint amountB, uint liquidity);
                  function addLiquidityETH(
                      address token,
                      uint amountTokenDesired,
                      uint amountTokenMin,
                      uint amountETHMin,
                      address to,
                      uint deadline
                  ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
                  function removeLiquidity(
                      address tokenA,
                      address tokenB,
                      uint liquidity,
                      uint amountAMin,
                      uint amountBMin,
                      address to,
                      uint deadline
                  ) external returns (uint amountA, uint amountB);
                  function removeLiquidityETH(
                      address token,
                      uint liquidity,
                      uint amountTokenMin,
                      uint amountETHMin,
                      address to,
                      uint deadline
                  ) external returns (uint amountToken, uint amountETH);
                  function removeLiquidityWithPermit(
                      address tokenA,
                      address tokenB,
                      uint liquidity,
                      uint amountAMin,
                      uint amountBMin,
                      address to,
                      uint deadline,
                      bool approveMax, uint8 v, bytes32 r, bytes32 s
                  ) external returns (uint amountA, uint amountB);
                  function removeLiquidityETHWithPermit(
                      address token,
                      uint liquidity,
                      uint amountTokenMin,
                      uint amountETHMin,
                      address to,
                      uint deadline,
                      bool approveMax, uint8 v, bytes32 r, bytes32 s
                  ) external returns (uint amountToken, uint amountETH);
                  function swapExactTokensForTokens(
                      uint amountIn,
                      uint amountOutMin,
                      address[] calldata path,
                      address to,
                      uint deadline
                  ) external returns (uint[] memory amounts);
                  function swapTokensForExactTokens(
                      uint amountOut,
                      uint amountInMax,
                      address[] calldata path,
                      address to,
                      uint deadline
                  ) external returns (uint[] memory amounts);
                  function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
                      external
                      payable
                      returns (uint[] memory amounts);
                  function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
                      external
                      returns (uint[] memory amounts);
                  function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
                      external
                      returns (uint[] memory amounts);
                  function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
                      external
                      payable
                      returns (uint[] memory amounts);
                  function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
                  function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
                  function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
                  function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
                  function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
              }
              pragma solidity ^0.6.0;
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
              import "@openzeppelin/contracts/utils/Address.sol";
              import "../Constants.sol";
              import "../IWETH.sol";
              contract WethAdapter {
                  using SafeERC20 for IERC20;
                  using Address for address;
                  using Address for address payable;
                  IWETH public immutable weth;
                  constructor(IWETH _weth) public {
                      weth = _weth;
                  }
                  /**
                   * @dev Performs a swap
                   * @param recipient The original msg.sender performing the swap
                   * @param aggregator Address of the aggregator's contract
                   * @param spender Address to which tokens will be approved
                   * @param method Selector of the function to be called in the aggregator's contract
                   * @param tokenFrom Token to be swapped
                   * @param tokenTo Token to be received
                   * @param amountFrom Amount of tokenFrom to swap
                   * @param amountTo Minimum amount of tokenTo to receive
                   * @param data Data used for the call made to the aggregator's contract
                   */
                  function swap(
                      address payable recipient,
                      address aggregator,
                      address spender,
                      bytes4 method,
                      IERC20 tokenFrom,
                      IERC20 tokenTo,
                      uint256 amountFrom,
                      uint256 amountTo,
                      bytes calldata data
                  ) external payable {
                      require(tokenFrom != tokenTo, "TOKEN_PAIR_INVALID");
                      if (address(tokenFrom) == Constants.ETH) {
                          // If tokenFrom is ETH, msg.value = fee + amountFrom (total fee could be 0)
                          // Can't deal with ETH, convert to WETH, the remaining balance will be the fee
                          weth.deposit{value: amountFrom}();
                          _approveSpender(weth, spender, amountFrom);
                      } else {
                          // Otherwise capture tokens from sender
                          _approveSpender(tokenFrom, spender, amountFrom);
                      }
                      // Perform the swap
                      aggregator.functionCallWithValue(
                          abi.encodePacked(method, data),
                          address(this).balance
                      );
                      // Transfer remaining balance of tokenFrom to sender
                      if (address(tokenFrom) != Constants.ETH) {
                          _transfer(tokenFrom, tokenFrom.balanceOf(address(this)), recipient);
                      } else {
                          // If using ETH, just unwrap any remaining WETH
                          // At the end of this function all ETH will be transferred to the sender
                          _unwrapWETH();
                      }
                      uint256 weiBalance = address(this).balance;
                      // Transfer remaining balance of tokenTo to sender
                      if (address(tokenTo) != Constants.ETH) {
                          uint256 balance = tokenTo.balanceOf(address(this));
                          require(balance >= amountTo, "INSUFFICIENT_AMOUNT");
                          _transfer(tokenTo, balance, recipient);
                      } else {
                          // If tokenTo == ETH, unwrap received WETH and add it to the wei balance,
                          // then check that the remaining ETH balance >= amountTo
                          // It is safe to not use safeMath as no one can have enough Ether to overflow
                          weiBalance += _unwrapWETH();
                          require(weiBalance >= amountTo, "INSUFFICIENT_AMOUNT");
                      }
                      // If there are unused fees or if tokenTo is ETH, transfer to sender
                      if (weiBalance > 0) {
                          recipient.sendValue(weiBalance);
                      }
                  }
                  /**
                   * @dev Unwraps all available WETH into ETH
                   */
                  function _unwrapWETH() internal returns (uint256) {
                      uint256 balance = weth.balanceOf(address(this));
                      weth.withdraw(balance);
                      return balance;
                  }
                  /**
                   * @dev Transfers token to sender if amount > 0
                   * @param token IERC20 token to transfer to sender
                   * @param amount Amount of token to transfer
                   * @param recipient Address that will receive the tokens
                   */
                  function _transfer(
                      IERC20 token,
                      uint256 amount,
                      address recipient
                  ) internal {
                      if (amount > 0) {
                          token.safeTransfer(recipient, amount);
                      }
                  }
                  // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/SafeERC20.sol
                  /**
                   * @dev Approves max amount of token to the spender if the allowance is lower than amount
                   * @param token The ERC20 token to approve
                   * @param spender Address to which funds will be approved
                   * @param amount Amount used to compare current allowance
                   */
                  function _approveSpender(
                      IERC20 token,
                      address spender,
                      uint256 amount
                  ) internal {
                      // If allowance is not enough, approve max possible amount
                      uint256 allowance = token.allowance(address(this), spender);
                      if (allowance < amount) {
                          bytes memory returndata = address(token).functionCall(
                              abi.encodeWithSelector(
                                  token.approve.selector,
                                  spender,
                                  type(uint256).max
                              )
                          );
                          if (returndata.length > 0) {
                              // Return data is optional
                              require(abi.decode(returndata, (bool)), "APPROVAL_FAILED");
                          }
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.6.0;
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              interface ICHI is IERC20 {
                  function freeUpTo(uint256 value) external returns (uint256);
                  function freeFromUpTo(
                      address from,
                      uint256 value
                  ) external returns (uint256);
                  function mint(uint256 value) external;
              }
                
              // SPDX-License-Identifier: UNLICENSED
              pragma solidity ^0.6.0;
              // We import the contract so truffle compiles it, and we have the ABI
              // available when working from truffle console.
              import "@openzeppelin/contracts/token/ERC20/ERC20.sol"; //helpers// SPDX-License-Identifier: MIT
              pragma solidity ^0.6.0;
              import "../../GSN/Context.sol";
              import "./IERC20.sol";
              import "../../math/SafeMath.sol";
              import "../../utils/Address.sol";
              /**
               * @dev Implementation of the {IERC20} interface.
               *
               * This implementation is agnostic to the way tokens are created. This means
               * that a supply mechanism has to be added in a derived contract using {_mint}.
               * For a generic mechanism see {ERC20PresetMinterPauser}.
               *
               * TIP: For a detailed writeup see our guide
               * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
               * to implement supply mechanisms].
               *
               * We have followed general OpenZeppelin guidelines: functions revert instead
               * of returning `false` on failure. This behavior is nonetheless conventional
               * and does not conflict with the expectations of ERC20 applications.
               *
               * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
               * This allows applications to reconstruct the allowance for all accounts just
               * by listening to said events. Other implementations of the EIP may not emit
               * these events, as it isn't required by the specification.
               *
               * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
               * functions have been added to mitigate the well-known issues around setting
               * allowances. See {IERC20-approve}.
               */
              contract ERC20 is Context, IERC20 {
                  using SafeMath for uint256;
                  using Address for address;
                  mapping (address => uint256) private _balances;
                  mapping (address => mapping (address => uint256)) private _allowances;
                  uint256 private _totalSupply;
                  string private _name;
                  string private _symbol;
                  uint8 private _decimals;
                  /**
                   * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
                   * a default value of 18.
                   *
                   * To select a different value for {decimals}, use {_setupDecimals}.
                   *
                   * All three of these values are immutable: they can only be set once during
                   * construction.
                   */
                  constructor (string memory name, string memory symbol) public {
                      _name = name;
                      _symbol = symbol;
                      _decimals = 18;
                  }
                  /**
                   * @dev Returns the name of the token.
                   */
                  function name() public view returns (string memory) {
                      return _name;
                  }
                  /**
                   * @dev Returns the symbol of the token, usually a shorter version of the
                   * name.
                   */
                  function symbol() public view returns (string memory) {
                      return _symbol;
                  }
                  /**
                   * @dev Returns the number of decimals used to get its user representation.
                   * For example, if `decimals` equals `2`, a balance of `505` tokens should
                   * be displayed to a user as `5,05` (`505 / 10 ** 2`).
                   *
                   * Tokens usually opt for a value of 18, imitating the relationship between
                   * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
                   * called.
                   *
                   * NOTE: This information is only used for _display_ purposes: it in
                   * no way affects any of the arithmetic of the contract, including
                   * {IERC20-balanceOf} and {IERC20-transfer}.
                   */
                  function decimals() public view returns (uint8) {
                      return _decimals;
                  }
                  /**
                   * @dev See {IERC20-totalSupply}.
                   */
                  function totalSupply() public view override returns (uint256) {
                      return _totalSupply;
                  }
                  /**
                   * @dev See {IERC20-balanceOf}.
                   */
                  function balanceOf(address account) public view override returns (uint256) {
                      return _balances[account];
                  }
                  /**
                   * @dev See {IERC20-transfer}.
                   *
                   * Requirements:
                   *
                   * - `recipient` cannot be the zero address.
                   * - the caller must have a balance of at least `amount`.
                   */
                  function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
                      _transfer(_msgSender(), recipient, amount);
                      return true;
                  }
                  /**
                   * @dev See {IERC20-allowance}.
                   */
                  function allowance(address owner, address spender) public view virtual override returns (uint256) {
                      return _allowances[owner][spender];
                  }
                  /**
                   * @dev See {IERC20-approve}.
                   *
                   * Requirements:
                   *
                   * - `spender` cannot be the zero address.
                   */
                  function approve(address spender, uint256 amount) public virtual override returns (bool) {
                      _approve(_msgSender(), spender, amount);
                      return true;
                  }
                  /**
                   * @dev See {IERC20-transferFrom}.
                   *
                   * Emits an {Approval} event indicating the updated allowance. This is not
                   * required by the EIP. See the note at the beginning of {ERC20};
                   *
                   * Requirements:
                   * - `sender` and `recipient` cannot be the zero address.
                   * - `sender` must have a balance of at least `amount`.
                   * - the caller must have allowance for ``sender``'s tokens of at least
                   * `amount`.
                   */
                  function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
                      _transfer(sender, recipient, amount);
                      _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
                      return true;
                  }
                  /**
                   * @dev Atomically increases the allowance granted to `spender` by the caller.
                   *
                   * This is an alternative to {approve} that can be used as a mitigation for
                   * problems described in {IERC20-approve}.
                   *
                   * Emits an {Approval} event indicating the updated allowance.
                   *
                   * Requirements:
                   *
                   * - `spender` cannot be the zero address.
                   */
                  function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
                      _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
                      return true;
                  }
                  /**
                   * @dev Atomically decreases the allowance granted to `spender` by the caller.
                   *
                   * This is an alternative to {approve} that can be used as a mitigation for
                   * problems described in {IERC20-approve}.
                   *
                   * Emits an {Approval} event indicating the updated allowance.
                   *
                   * Requirements:
                   *
                   * - `spender` cannot be the zero address.
                   * - `spender` must have allowance for the caller of at least
                   * `subtractedValue`.
                   */
                  function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
                      _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
                      return true;
                  }
                  /**
                   * @dev Moves tokens `amount` from `sender` to `recipient`.
                   *
                   * This is internal function is equivalent to {transfer}, and can be used to
                   * e.g. implement automatic token fees, slashing mechanisms, etc.
                   *
                   * Emits a {Transfer} event.
                   *
                   * Requirements:
                   *
                   * - `sender` cannot be the zero address.
                   * - `recipient` cannot be the zero address.
                   * - `sender` must have a balance of at least `amount`.
                   */
                  function _transfer(address sender, address recipient, uint256 amount) internal virtual {
                      require(sender != address(0), "ERC20: transfer from the zero address");
                      require(recipient != address(0), "ERC20: transfer to the zero address");
                      _beforeTokenTransfer(sender, recipient, amount);
                      _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
                      _balances[recipient] = _balances[recipient].add(amount);
                      emit Transfer(sender, recipient, amount);
                  }
                  /** @dev Creates `amount` tokens and assigns them to `account`, increasing
                   * the total supply.
                   *
                   * Emits a {Transfer} event with `from` set to the zero address.
                   *
                   * Requirements
                   *
                   * - `to` cannot be the zero address.
                   */
                  function _mint(address account, uint256 amount) internal virtual {
                      require(account != address(0), "ERC20: mint to the zero address");
                      _beforeTokenTransfer(address(0), account, amount);
                      _totalSupply = _totalSupply.add(amount);
                      _balances[account] = _balances[account].add(amount);
                      emit Transfer(address(0), account, amount);
                  }
                  /**
                   * @dev Destroys `amount` tokens from `account`, reducing the
                   * total supply.
                   *
                   * Emits a {Transfer} event with `to` set to the zero address.
                   *
                   * Requirements
                   *
                   * - `account` cannot be the zero address.
                   * - `account` must have at least `amount` tokens.
                   */
                  function _burn(address account, uint256 amount) internal virtual {
                      require(account != address(0), "ERC20: burn from the zero address");
                      _beforeTokenTransfer(account, address(0), amount);
                      _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
                      _totalSupply = _totalSupply.sub(amount);
                      emit Transfer(account, address(0), amount);
                  }
                  /**
                   * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
                   *
                   * This internal function is equivalent to `approve`, and can be used to
                   * e.g. set automatic allowances for certain subsystems, etc.
                   *
                   * Emits an {Approval} event.
                   *
                   * Requirements:
                   *
                   * - `owner` cannot be the zero address.
                   * - `spender` cannot be the zero address.
                   */
                  function _approve(address owner, address spender, uint256 amount) internal virtual {
                      require(owner != address(0), "ERC20: approve from the zero address");
                      require(spender != address(0), "ERC20: approve to the zero address");
                      _allowances[owner][spender] = amount;
                      emit Approval(owner, spender, amount);
                  }
                  /**
                   * @dev Sets {decimals} to a value other than the default one of 18.
                   *
                   * WARNING: This function should only be called from the constructor. Most
                   * applications that interact with token contracts will not expect
                   * {decimals} to ever change, and may work incorrectly if it does.
                   */
                  function _setupDecimals(uint8 decimals_) internal {
                      _decimals = decimals_;
                  }
                  /**
                   * @dev Hook that is called before any transfer of tokens. This includes
                   * minting and burning.
                   *
                   * Calling conditions:
                   *
                   * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
                   * will be to transferred to `to`.
                   * - when `from` is zero, `amount` tokens will be minted for `to`.
                   * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
                   * - `from` and `to` are never both zero.
                   *
                   * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
                   */
                  function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.6.0;
              /*
               * @dev Provides information about the current execution context, including the
               * sender of the transaction and its data. While these are generally available
               * via msg.sender and msg.data, they should not be accessed in such a direct
               * manner, since when dealing with GSN meta-transactions the account sending and
               * paying for execution may not be the actual sender (as far as an application
               * is concerned).
               *
               * This contract is only required for intermediate, library-like contracts.
               */
              abstract contract Context {
                  function _msgSender() internal view virtual returns (address payable) {
                      return msg.sender;
                  }
                  function _msgData() internal view virtual returns (bytes memory) {
                      this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                      return msg.data;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.6.0;
              import "@openzeppelin/contracts/access/Ownable.sol";
              import "@openzeppelin/contracts/utils/Pausable.sol";
              import "@openzeppelin/contracts/utils/Address.sol";
              import "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
              import "./ICHI.sol";
              import "./Spender.sol";
              /**
               * @title MetaSwap
               */
              contract MetaSwap is Ownable, Pausable, ReentrancyGuard {
                  using SafeERC20 for IERC20;
                  using Address for address;
                  using Address for address payable;
                  struct Adapter {
                      address addr; // adapter's address
                      bytes4 selector;
                      bytes data; // adapter's fixed data
                  }
                  ICHI public immutable chi;
                  Spender public immutable spender;
                  // Mapping of aggregatorId to aggregator
                  mapping(string => Adapter) public adapters;
                  mapping(string => bool) public adapterRemoved;
                  event AdapterSet(
                      string indexed aggregatorId,
                      address indexed addr,
                      bytes4 selector,
                      bytes data
                  );
                  event AdapterRemoved(string indexed aggregatorId);
                  event Swap(string indexed aggregatorId, address indexed sender);
                  constructor(ICHI _chi) public {
                      chi = _chi;
                      spender = new Spender();
                  }
                  /**
                   * @dev Sets the adapter for an aggregator. It can't be changed later.
                   * @param aggregatorId Aggregator's identifier
                   * @param addr Address of the contract that contains the logic for this aggregator
                   * @param selector The function selector of the swap function in the adapter
                   * @param data Fixed abi encoded data the will be passed in each delegatecall made to the adapter
                   */
                  function setAdapter(
                      string calldata aggregatorId,
                      address addr,
                      bytes4 selector,
                      bytes calldata data
                  ) external onlyOwner {
                      require(addr.isContract(), "ADAPTER_IS_NOT_A_CONTRACT");
                      require(!adapterRemoved[aggregatorId], "ADAPTER_REMOVED");
                      Adapter storage adapter = adapters[aggregatorId];
                      require(adapter.addr == address(0), "ADAPTER_EXISTS");
                      adapter.addr = addr;
                      adapter.selector = selector;
                      adapter.data = data;
                      emit AdapterSet(aggregatorId, addr, selector, data);
                  }
                  /**
                   * @dev Removes the adapter for an existing aggregator. This can't be undone.
                   * @param aggregatorId Aggregator's identifier
                   */
                  function removeAdapter(string calldata aggregatorId) external onlyOwner {
                      require(
                          adapters[aggregatorId].addr != address(0),
                          "ADAPTER_DOES_NOT_EXIST"
                      );
                      delete adapters[aggregatorId];
                      adapterRemoved[aggregatorId] = true;
                      emit AdapterRemoved(aggregatorId);
                  }
                  /**
                   * @dev Performs a swap
                   * @param aggregatorId Identifier of the aggregator to be used for the swap
                   * @param data Dynamic data which is concatenated with the fixed aggregator's
                   * data in the delecatecall made to the adapter
                   */
                  function swap(
                      string calldata aggregatorId,
                      IERC20 tokenFrom,
                      uint256 amount,
                      bytes calldata data
                  ) external payable whenNotPaused nonReentrant {
                      _swap(aggregatorId, tokenFrom, amount, data);
                  }
                  /**
                   * @dev Performs a swap
                   * @param aggregatorId Identifier of the aggregator to be used for the swap
                   * @param data Dynamic data which is concatenated with the fixed aggregator's
                   * data in the delecatecall made to the adapter
                   */
                  function swapUsingGasToken(
                      string calldata aggregatorId,
                      IERC20 tokenFrom,
                      uint256 amount,
                      bytes calldata data
                  ) external payable whenNotPaused nonReentrant {
                      uint256 gas = gasleft();
                      _swap(aggregatorId, tokenFrom, amount, data);
                      uint256 gasSpent = 21000 + gas - gasleft() + 16 * msg.data.length;
                      chi.freeFromUpTo(msg.sender, (gasSpent + 14154) / 41947);
                  }
                  function pauseSwaps() external onlyOwner {
                      _pause();
                  }
                  function unpauseSwaps() external onlyOwner {
                      _unpause();
                  }
                  function _swap(
                      string calldata aggregatorId,
                      IERC20 tokenFrom,
                      uint256 amount,
                      bytes calldata data
                  ) internal {
                      Adapter storage adapter = adapters[aggregatorId];
                      if (address(tokenFrom) != Constants.ETH) {
                          tokenFrom.safeTransferFrom(msg.sender, address(spender), amount);
                      }
                      spender.swap{value: msg.value}(
                          adapter.addr,
                          abi.encodePacked(
                              adapter.selector,
                              abi.encode(msg.sender),
                              adapter.data,
                              data
                          )
                      );
                      emit Swap(aggregatorId, msg.sender);
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.6.0;
              import "../GSN/Context.sol";
              /**
               * @dev Contract module which provides a basic access control mechanism, where
               * there is an account (an owner) that can be granted exclusive access to
               * specific functions.
               *
               * By default, the owner account will be the one that deploys the contract. This
               * can later be changed with {transferOwnership}.
               *
               * This module is used through inheritance. It will make available the modifier
               * `onlyOwner`, which can be applied to your functions to restrict their use to
               * the owner.
               */
              contract Ownable is Context {
                  address private _owner;
                  event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                  /**
                   * @dev Initializes the contract setting the deployer as the initial owner.
                   */
                  constructor () internal {
                      address msgSender = _msgSender();
                      _owner = msgSender;
                      emit OwnershipTransferred(address(0), msgSender);
                  }
                  /**
                   * @dev Returns the address of the current owner.
                   */
                  function owner() public view returns (address) {
                      return _owner;
                  }
                  /**
                   * @dev Throws if called by any account other than the owner.
                   */
                  modifier onlyOwner() {
                      require(_owner == _msgSender(), "Ownable: caller is not the owner");
                      _;
                  }
                  /**
                   * @dev Leaves the contract without owner. It will not be possible to call
                   * `onlyOwner` functions anymore. Can only be called by the current owner.
                   *
                   * NOTE: Renouncing ownership will leave the contract without an owner,
                   * thereby removing any functionality that is only available to the owner.
                   */
                  function renounceOwnership() public virtual onlyOwner {
                      emit OwnershipTransferred(_owner, address(0));
                      _owner = address(0);
                  }
                  /**
                   * @dev Transfers ownership of the contract to a new account (`newOwner`).
                   * Can only be called by the current owner.
                   */
                  function transferOwnership(address newOwner) public virtual onlyOwner {
                      require(newOwner != address(0), "Ownable: new owner is the zero address");
                      emit OwnershipTransferred(_owner, newOwner);
                      _owner = newOwner;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.6.0;
              import "../GSN/Context.sol";
              /**
               * @dev Contract module which allows children to implement an emergency stop
               * mechanism that can be triggered by an authorized account.
               *
               * This module is used through inheritance. It will make available the
               * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
               * the functions of your contract. Note that they will not be pausable by
               * simply including this module, only once the modifiers are put in place.
               */
              contract Pausable is Context {
                  /**
                   * @dev Emitted when the pause is triggered by `account`.
                   */
                  event Paused(address account);
                  /**
                   * @dev Emitted when the pause is lifted by `account`.
                   */
                  event Unpaused(address account);
                  bool private _paused;
                  /**
                   * @dev Initializes the contract in unpaused state.
                   */
                  constructor () internal {
                      _paused = false;
                  }
                  /**
                   * @dev Returns true if the contract is paused, and false otherwise.
                   */
                  function paused() public view returns (bool) {
                      return _paused;
                  }
                  /**
                   * @dev Modifier to make a function callable only when the contract is not paused.
                   *
                   * Requirements:
                   *
                   * - The contract must not be paused.
                   */
                  modifier whenNotPaused() {
                      require(!_paused, "Pausable: paused");
                      _;
                  }
                  /**
                   * @dev Modifier to make a function callable only when the contract is paused.
                   *
                   * Requirements:
                   *
                   * - The contract must be paused.
                   */
                  modifier whenPaused() {
                      require(_paused, "Pausable: not paused");
                      _;
                  }
                  /**
                   * @dev Triggers stopped state.
                   *
                   * Requirements:
                   *
                   * - The contract must not be paused.
                   */
                  function _pause() internal virtual whenNotPaused {
                      _paused = true;
                      emit Paused(_msgSender());
                  }
                  /**
                   * @dev Returns to normal state.
                   *
                   * Requirements:
                   *
                   * - The contract must be paused.
                   */
                  function _unpause() internal virtual whenPaused {
                      _paused = false;
                      emit Unpaused(_msgSender());
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.6.0;
              /**
               * @dev Contract module that helps prevent reentrant calls to a function.
               *
               * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
               * available, which can be applied to functions to make sure there are no nested
               * (reentrant) calls to them.
               *
               * Note that because there is a single `nonReentrant` guard, functions marked as
               * `nonReentrant` may not call one another. This can be worked around by making
               * those functions `private`, and then adding `external` `nonReentrant` entry
               * points to them.
               *
               * TIP: If you would like to learn more about reentrancy and alternative ways
               * to protect against it, check out our blog post
               * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
               */
              contract ReentrancyGuard {
                  // Booleans are more expensive than uint256 or any type that takes up a full
                  // word because each write operation emits an extra SLOAD to first read the
                  // slot's contents, replace the bits taken up by the boolean, and then write
                  // back. This is the compiler's defense against contract upgrades and
                  // pointer aliasing, and it cannot be disabled.
                  // The values being non-zero value makes deployment a bit more expensive,
                  // but in exchange the refund on every call to nonReentrant will be lower in
                  // amount. Since refunds are capped to a percentage of the total
                  // transaction's gas, it is best to keep them low in cases like this one, to
                  // increase the likelihood of the full refund coming into effect.
                  uint256 private constant _NOT_ENTERED = 1;
                  uint256 private constant _ENTERED = 2;
                  uint256 private _status;
                  constructor () internal {
                      _status = _NOT_ENTERED;
                  }
                  /**
                   * @dev Prevents a contract from calling itself, directly or indirectly.
                   * Calling a `nonReentrant` function from another `nonReentrant`
                   * function is not supported. It is possible to prevent this from happening
                   * by making the `nonReentrant` function external, and make it call a
                   * `private` function that does the actual work.
                   */
                  modifier nonReentrant() {
                      // On the first call to nonReentrant, _notEntered will be true
                      require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
                      // Any calls to nonReentrant after this point will fail
                      _status = _ENTERED;
                      _;
                      // By storing the original value once again, a refund is triggered (see
                      // https://eips.ethereum.org/EIPS/eip-2200)
                      _status = _NOT_ENTERED;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.6.0;
              import "./Constants.sol";
              contract Spender {
                  address public immutable metaswap;
                  constructor() public {
                      metaswap = msg.sender;
                  }
                  /// @dev Receives ether from swaps
                  fallback() external payable {}
                  function swap(address adapter, bytes calldata data) external payable {
                      require(msg.sender == metaswap, "FORBIDDEN");
                      require(adapter != address(0), "ADAPTER_NOT_PROVIDED");
                      _delegate(adapter, data, "ADAPTER_DELEGATECALL_FAILED");
                  }
                  /**
                   * @dev Performs a delegatecall and bubbles up the errors, adapted from
                   * https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Address.sol
                   * @param target Address of the contract to delegatecall
                   * @param data Data passed in the delegatecall
                   * @param errorMessage Fallback revert reason
                   */
                  function _delegate(
                      address target,
                      bytes memory data,
                      string memory errorMessage
                  ) private returns (bytes memory) {
                      // solhint-disable-next-line avoid-low-level-calls
                      (bool success, bytes memory returndata) = target.delegatecall(data);
                      if (success) {
                          return returndata;
                      } else {
                          // Look for revert reason and bubble it up if present
                          if (returndata.length > 0) {
                              // The easiest way to bubble the revert reason is using memory via assembly
                              // solhint-disable-next-line no-inline-assembly
                              assembly {
                                  let returndata_size := mload(returndata)
                                  revert(add(32, returndata), returndata_size)
                              }
                          } else {
                              revert(errorMessage);
                          }
                      }
                  }
              }
              pragma solidity ^0.6.0;
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
              import "@openzeppelin/contracts/utils/Address.sol";
              contract MockAdapter {
                  using SafeERC20 for IERC20;
                  using Address for address;
                  using Address for address payable;
                  event MockAdapterEvent(
                      address sender,
                      uint256 valueFixed,
                      uint256 valueDynamic
                  );
                  function test(
                      address sender,
                      uint256 valueFixed,
                      uint256 valueDynamic
                  ) external payable {
                      emit MockAdapterEvent(sender, valueFixed, valueDynamic);
                  }
                  function testRevert(
                      address,
                      uint256,
                      uint256
                  ) external payable {
                      revert("SWAP_FAILED");
                  }
                  function testRevertNoReturnData(
                      address,
                      uint256,
                      uint256
                  ) external payable {
                      revert();
                  }
              }
              pragma solidity ^0.6.0;
              // TAKEN FROM https://github.com/gnosis/mock-contract
              // TODO: use their npm package once it is published for solidity 0.6
              interface MockInterface {
                  /**
                   * @dev After calling this method, the mock will return `response` when it is called
                   * with any calldata that is not mocked more specifically below
                   * (e.g. using givenMethodReturn).
                   * @param response ABI encoded response that will be returned if method is invoked
                   */
                  function givenAnyReturn(bytes calldata response) external;
                  function givenAnyReturnBool(bool response) external;
                  function givenAnyReturnUint(uint256 response) external;
                  function givenAnyReturnAddress(address response) external;
                  function givenAnyRevert() external;
                  function givenAnyRevertWithMessage(string calldata message) external;
                  function givenAnyRunOutOfGas() external;
                  /**
                   * @dev After calling this method, the mock will return `response` when the given
                   * methodId is called regardless of arguments. If the methodId and arguments
                   * are mocked more specifically (using `givenMethodAndArguments`) the latter
                   * will take precedence.
                   * @param method ABI encoded methodId. It is valid to pass full calldata (including arguments). The mock will extract the methodId from it
                   * @param response ABI encoded response that will be returned if method is invoked
                   */
                  function givenMethodReturn(bytes calldata method, bytes calldata response)
                      external;
                  function givenMethodReturnBool(bytes calldata method, bool response)
                      external;
                  function givenMethodReturnUint(bytes calldata method, uint256 response)
                      external;
                  function givenMethodReturnAddress(bytes calldata method, address response)
                      external;
                  function givenMethodRevert(bytes calldata method) external;
                  function givenMethodRevertWithMessage(
                      bytes calldata method,
                      string calldata message
                  ) external;
                  function givenMethodRunOutOfGas(bytes calldata method) external;
                  /**
                   * @dev After calling this method, the mock will return `response` when the given
                   * methodId is called with matching arguments. These exact calldataMocks will take
                   * precedence over all other calldataMocks.
                   * @param call ABI encoded calldata (methodId and arguments)
                   * @param response ABI encoded response that will be returned if contract is invoked with calldata
                   */
                  function givenCalldataReturn(bytes calldata call, bytes calldata response)
                      external;
                  function givenCalldataReturnBool(bytes calldata call, bool response)
                      external;
                  function givenCalldataReturnUint(bytes calldata call, uint256 response)
                      external;
                  function givenCalldataReturnAddress(bytes calldata call, address response)
                      external;
                  function givenCalldataRevert(bytes calldata call) external;
                  function givenCalldataRevertWithMessage(
                      bytes calldata call,
                      string calldata message
                  ) external;
                  function givenCalldataRunOutOfGas(bytes calldata call) external;
                  /**
                   * @dev Returns the number of times anything has been called on this mock since last reset
                   */
                  function invocationCount() external returns (uint256);
                  /**
                   * @dev Returns the number of times the given method has been called on this mock since last reset
                   * @param method ABI encoded methodId. It is valid to pass full calldata (including arguments). The mock will extract the methodId from it
                   */
                  function invocationCountForMethod(bytes calldata method)
                      external
                      returns (uint256);
                  /**
                   * @dev Returns the number of times this mock has been called with the exact calldata since last reset.
                   * @param call ABI encoded calldata (methodId and arguments)
                   */
                  function invocationCountForCalldata(bytes calldata call)
                      external
                      returns (uint256);
                  /**
                   * @dev Resets all mocked methods and invocation counts.
                   */
                  function reset() external;
              }
              /**
               * Implementation of the MockInterface.
               */
              contract MockContract is MockInterface {
                  enum MockType {Return, Revert, OutOfGas}
                  bytes32 public constant MOCKS_LIST_START = hex"01";
                  bytes public constant MOCKS_LIST_END = "0xff";
                  bytes32 public constant MOCKS_LIST_END_HASH = keccak256(MOCKS_LIST_END);
                  bytes4 public constant SENTINEL_ANY_MOCKS = hex"01";
                  bytes public constant DEFAULT_FALLBACK_VALUE = abi.encode(false);
                  // A linked list allows easy iteration and inclusion checks
                  mapping(bytes32 => bytes) calldataMocks;
                  mapping(bytes => MockType) calldataMockTypes;
                  mapping(bytes => bytes) calldataExpectations;
                  mapping(bytes => string) calldataRevertMessage;
                  mapping(bytes32 => uint256) calldataInvocations;
                  mapping(bytes4 => bytes4) methodIdMocks;
                  mapping(bytes4 => MockType) methodIdMockTypes;
                  mapping(bytes4 => bytes) methodIdExpectations;
                  mapping(bytes4 => string) methodIdRevertMessages;
                  mapping(bytes32 => uint256) methodIdInvocations;
                  MockType fallbackMockType;
                  bytes fallbackExpectation = DEFAULT_FALLBACK_VALUE;
                  string fallbackRevertMessage;
                  uint256 invocations;
                  uint256 resetCount;
                  constructor() public {
                      calldataMocks[MOCKS_LIST_START] = MOCKS_LIST_END;
                      methodIdMocks[SENTINEL_ANY_MOCKS] = SENTINEL_ANY_MOCKS;
                  }
                  function trackCalldataMock(bytes memory call) private {
                      bytes32 callHash = keccak256(call);
                      if (calldataMocks[callHash].length == 0) {
                          calldataMocks[callHash] = calldataMocks[MOCKS_LIST_START];
                          calldataMocks[MOCKS_LIST_START] = call;
                      }
                  }
                  function trackMethodIdMock(bytes4 methodId) private {
                      if (methodIdMocks[methodId] == 0x0) {
                          methodIdMocks[methodId] = methodIdMocks[SENTINEL_ANY_MOCKS];
                          methodIdMocks[SENTINEL_ANY_MOCKS] = methodId;
                      }
                  }
                  function _givenAnyReturn(bytes memory response) internal {
                      fallbackMockType = MockType.Return;
                      fallbackExpectation = response;
                  }
                  function givenAnyReturn(bytes calldata response) external override {
                      _givenAnyReturn(response);
                  }
                  function givenAnyReturnBool(bool response) external override {
                      uint256 flag = response ? 1 : 0;
                      _givenAnyReturn(uintToBytes(flag));
                  }
                  function givenAnyReturnUint(uint256 response) external override {
                      _givenAnyReturn(uintToBytes(response));
                  }
                  function givenAnyReturnAddress(address response) external override {
                      _givenAnyReturn(uintToBytes(uint256(response)));
                  }
                  function givenAnyRevert() external override {
                      fallbackMockType = MockType.Revert;
                      fallbackRevertMessage = "";
                  }
                  function givenAnyRevertWithMessage(string calldata message)
                      external
                      override
                  {
                      fallbackMockType = MockType.Revert;
                      fallbackRevertMessage = message;
                  }
                  function givenAnyRunOutOfGas() external override {
                      fallbackMockType = MockType.OutOfGas;
                  }
                  function _givenCalldataReturn(bytes memory call, bytes memory response)
                      private
                  {
                      calldataMockTypes[call] = MockType.Return;
                      calldataExpectations[call] = response;
                      trackCalldataMock(call);
                  }
                  function givenCalldataReturn(bytes calldata call, bytes calldata response)
                      external
                      override
                  {
                      _givenCalldataReturn(call, response);
                  }
                  function givenCalldataReturnBool(bytes calldata call, bool response)
                      external
                      override
                  {
                      uint256 flag = response ? 1 : 0;
                      _givenCalldataReturn(call, uintToBytes(flag));
                  }
                  function givenCalldataReturnUint(bytes calldata call, uint256 response)
                      external
                      override
                  {
                      _givenCalldataReturn(call, uintToBytes(response));
                  }
                  function givenCalldataReturnAddress(bytes calldata call, address response)
                      external
                      override
                  {
                      _givenCalldataReturn(call, uintToBytes(uint256(response)));
                  }
                  function _givenMethodReturn(bytes memory call, bytes memory response)
                      private
                  {
                      bytes4 method = bytesToBytes4(call);
                      methodIdMockTypes[method] = MockType.Return;
                      methodIdExpectations[method] = response;
                      trackMethodIdMock(method);
                  }
                  function givenMethodReturn(bytes calldata call, bytes calldata response)
                      external
                      override
                  {
                      _givenMethodReturn(call, response);
                  }
                  function givenMethodReturnBool(bytes calldata call, bool response)
                      external
                      override
                  {
                      uint256 flag = response ? 1 : 0;
                      _givenMethodReturn(call, uintToBytes(flag));
                  }
                  function givenMethodReturnUint(bytes calldata call, uint256 response)
                      external
                      override
                  {
                      _givenMethodReturn(call, uintToBytes(response));
                  }
                  function givenMethodReturnAddress(bytes calldata call, address response)
                      external
                      override
                  {
                      _givenMethodReturn(call, uintToBytes(uint256(response)));
                  }
                  function givenCalldataRevert(bytes calldata call) external override {
                      calldataMockTypes[call] = MockType.Revert;
                      calldataRevertMessage[call] = "";
                      trackCalldataMock(call);
                  }
                  function givenMethodRevert(bytes calldata call) external override {
                      bytes4 method = bytesToBytes4(call);
                      methodIdMockTypes[method] = MockType.Revert;
                      trackMethodIdMock(method);
                  }
                  function givenCalldataRevertWithMessage(
                      bytes calldata call,
                      string calldata message
                  ) external override {
                      calldataMockTypes[call] = MockType.Revert;
                      calldataRevertMessage[call] = message;
                      trackCalldataMock(call);
                  }
                  function givenMethodRevertWithMessage(
                      bytes calldata call,
                      string calldata message
                  ) external override {
                      bytes4 method = bytesToBytes4(call);
                      methodIdMockTypes[method] = MockType.Revert;
                      methodIdRevertMessages[method] = message;
                      trackMethodIdMock(method);
                  }
                  function givenCalldataRunOutOfGas(bytes calldata call) external override {
                      calldataMockTypes[call] = MockType.OutOfGas;
                      trackCalldataMock(call);
                  }
                  function givenMethodRunOutOfGas(bytes calldata call) external override {
                      bytes4 method = bytesToBytes4(call);
                      methodIdMockTypes[method] = MockType.OutOfGas;
                      trackMethodIdMock(method);
                  }
                  function invocationCount() external override returns (uint256) {
                      return invocations;
                  }
                  function invocationCountForMethod(bytes calldata call)
                      external
                      override
                      returns (uint256)
                  {
                      bytes4 method = bytesToBytes4(call);
                      return
                          methodIdInvocations[keccak256(
                              abi.encodePacked(resetCount, method)
                          )];
                  }
                  function invocationCountForCalldata(bytes calldata call)
                      external
                      override
                      returns (uint256)
                  {
                      return
                          calldataInvocations[keccak256(abi.encodePacked(resetCount, call))];
                  }
                  function reset() external override {
                      // Reset all exact calldataMocks
                      bytes memory nextMock = calldataMocks[MOCKS_LIST_START];
                      bytes32 mockHash = keccak256(nextMock);
                      // We cannot compary bytes
                      while (mockHash != MOCKS_LIST_END_HASH) {
                          // Reset all mock maps
                          calldataMockTypes[nextMock] = MockType.Return;
                          calldataExpectations[nextMock] = hex"";
                          calldataRevertMessage[nextMock] = "";
                          // Set next mock to remove
                          nextMock = calldataMocks[mockHash];
                          // Remove from linked list
                          calldataMocks[mockHash] = "";
                          // Update mock hash
                          mockHash = keccak256(nextMock);
                      }
                      // Clear list
                      calldataMocks[MOCKS_LIST_START] = MOCKS_LIST_END;
                      // Reset all any calldataMocks
                      bytes4 nextAnyMock = methodIdMocks[SENTINEL_ANY_MOCKS];
                      while (nextAnyMock != SENTINEL_ANY_MOCKS) {
                          bytes4 currentAnyMock = nextAnyMock;
                          methodIdMockTypes[currentAnyMock] = MockType.Return;
                          methodIdExpectations[currentAnyMock] = hex"";
                          methodIdRevertMessages[currentAnyMock] = "";
                          nextAnyMock = methodIdMocks[currentAnyMock];
                          // Remove from linked list
                          methodIdMocks[currentAnyMock] = 0x0;
                      }
                      // Clear list
                      methodIdMocks[SENTINEL_ANY_MOCKS] = SENTINEL_ANY_MOCKS;
                      fallbackExpectation = DEFAULT_FALLBACK_VALUE;
                      fallbackMockType = MockType.Return;
                      invocations = 0;
                      resetCount += 1;
                  }
                  function useAllGas() private {
                      while (true) {
                          bool s;
                          assembly {
                              //expensive call to EC multiply contract
                              s := call(sub(gas(), 2000), 6, 0, 0x0, 0xc0, 0x0, 0x60)
                          }
                      }
                  }
                  function bytesToBytes4(bytes memory b) private pure returns (bytes4) {
                      bytes4 out;
                      for (uint256 i = 0; i < 4; i++) {
                          out |= bytes4(b[i] & 0xFF) >> (i * 8);
                      }
                      return out;
                  }
                  function uintToBytes(uint256 x) private pure returns (bytes memory b) {
                      b = new bytes(32);
                      assembly {
                          mstore(add(b, 32), x)
                      }
                  }
                  function updateInvocationCount(
                      bytes4 methodId,
                      bytes memory originalMsgData
                  ) public {
                      require(
                          msg.sender == address(this),
                          "Can only be called from the contract itself"
                      );
                      invocations += 1;
                      methodIdInvocations[keccak256(
                          abi.encodePacked(resetCount, methodId)
                      )] += 1;
                      calldataInvocations[keccak256(
                          abi.encodePacked(resetCount, originalMsgData)
                      )] += 1;
                  }
                  fallback() external payable {
                      bytes4 methodId;
                      assembly {
                          methodId := calldataload(0)
                      }
                      // First, check exact matching overrides
                      if (calldataMockTypes[msg.data] == MockType.Revert) {
                          revert(calldataRevertMessage[msg.data]);
                      }
                      if (calldataMockTypes[msg.data] == MockType.OutOfGas) {
                          useAllGas();
                      }
                      bytes memory result = calldataExpectations[msg.data];
                      // Then check method Id overrides
                      if (result.length == 0) {
                          if (methodIdMockTypes[methodId] == MockType.Revert) {
                              revert(methodIdRevertMessages[methodId]);
                          }
                          if (methodIdMockTypes[methodId] == MockType.OutOfGas) {
                              useAllGas();
                          }
                          result = methodIdExpectations[methodId];
                      }
                      // Last, use the fallback override
                      if (result.length == 0) {
                          if (fallbackMockType == MockType.Revert) {
                              revert(fallbackRevertMessage);
                          }
                          if (fallbackMockType == MockType.OutOfGas) {
                              useAllGas();
                          }
                          result = fallbackExpectation;
                      }
                      // Record invocation as separate call so we don't rollback in case we are called with STATICCALL
                      (, bytes memory r) = address(this).call{gas: 100000}(
                          abi.encodeWithSignature(
                              "updateInvocationCount(bytes4,bytes)",
                              methodId,
                              msg.data
                          )
                      );
                      assert(r.length == 0);
                      assembly {
                          return(add(0x20, result), mload(result))
                      }
                  }
              }
              pragma solidity ^0.6.0;
              contract MockSelfDestruct {
                  constructor() public payable {}
                  fallback() external payable {
                      selfdestruct(msg.sender);
                  }
                  function kill(address payable target) external payable {
                      selfdestruct(target);
                  }
              }
              

              File 2 of 6: DexRouter
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable.sol)
              pragma solidity ^0.8.0;
              import "../utils/ContextUpgradeable.sol";
              import "../proxy/utils/Initializable.sol";
              /**
               * @dev Contract module which provides a basic access control mechanism, where
               * there is an account (an owner) that can be granted exclusive access to
               * specific functions.
               *
               * By default, the owner account will be the one that deploys the contract. This
               * can later be changed with {transferOwnership}.
               *
               * This module is used through inheritance. It will make available the modifier
               * `onlyOwner`, which can be applied to your functions to restrict their use to
               * the owner.
               */
              abstract contract OwnableUpgradeable is Initializable, ContextUpgradeable {
                  address private _owner;
                  event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                  /**
                   * @dev Initializes the contract setting the deployer as the initial owner.
                   */
                  function __Ownable_init() internal onlyInitializing {
                      __Ownable_init_unchained();
                  }
                  function __Ownable_init_unchained() internal onlyInitializing {
                      _transferOwnership(_msgSender());
                  }
                  /**
                   * @dev Throws if called by any account other than the owner.
                   */
                  modifier onlyOwner() {
                      _checkOwner();
                      _;
                  }
                  /**
                   * @dev Returns the address of the current owner.
                   */
                  function owner() public view virtual returns (address) {
                      return _owner;
                  }
                  /**
                   * @dev Throws if the sender is not the owner.
                   */
                  function _checkOwner() internal view virtual {
                      require(owner() == _msgSender(), "Ownable: caller is not the owner");
                  }
                  /**
                   * @dev Leaves the contract without owner. It will not be possible to call
                   * `onlyOwner` functions. Can only be called by the current owner.
                   *
                   * NOTE: Renouncing ownership will leave the contract without an owner,
                   * thereby disabling any functionality that is only available to the owner.
                   */
                  function renounceOwnership() public virtual onlyOwner {
                      _transferOwnership(address(0));
                  }
                  /**
                   * @dev Transfers ownership of the contract to a new account (`newOwner`).
                   * Can only be called by the current owner.
                   */
                  function transferOwnership(address newOwner) public virtual onlyOwner {
                      require(newOwner != address(0), "Ownable: new owner is the zero address");
                      _transferOwnership(newOwner);
                  }
                  /**
                   * @dev Transfers ownership of the contract to a new account (`newOwner`).
                   * Internal function without access restriction.
                   */
                  function _transferOwnership(address newOwner) internal virtual {
                      address oldOwner = _owner;
                      _owner = newOwner;
                      emit OwnershipTransferred(oldOwner, newOwner);
                  }
                  /**
                   * @dev This empty reserved space is put in place to allow future versions to add new
                   * variables without shifting down storage in the inheritance chain.
                   * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                   */
                  uint256[49] private __gap;
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts (last updated v4.9.0) (proxy/utils/Initializable.sol)
              pragma solidity ^0.8.2;
              import "../../utils/AddressUpgradeable.sol";
              /**
               * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
               * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
               * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
               * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
               *
               * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
               * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
               * case an upgrade adds a module that needs to be initialized.
               *
               * For example:
               *
               * [.hljs-theme-light.nopadding]
               * ```solidity
               * contract MyToken is ERC20Upgradeable {
               *     function initialize() initializer public {
               *         __ERC20_init("MyToken", "MTK");
               *     }
               * }
               *
               * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
               *     function initializeV2() reinitializer(2) public {
               *         __ERC20Permit_init("MyToken");
               *     }
               * }
               * ```
               *
               * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
               * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
               *
               * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
               * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
               *
               * [CAUTION]
               * ====
               * Avoid leaving a contract uninitialized.
               *
               * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
               * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
               * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
               *
               * [.hljs-theme-light.nopadding]
               * ```
               * /// @custom:oz-upgrades-unsafe-allow constructor
               * constructor() {
               *     _disableInitializers();
               * }
               * ```
               * ====
               */
              abstract contract Initializable {
                  /**
                   * @dev Indicates that the contract has been initialized.
                   * @custom:oz-retyped-from bool
                   */
                  uint8 private _initialized;
                  /**
                   * @dev Indicates that the contract is in the process of being initialized.
                   */
                  bool private _initializing;
                  /**
                   * @dev Triggered when the contract has been initialized or reinitialized.
                   */
                  event Initialized(uint8 version);
                  /**
                   * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
                   * `onlyInitializing` functions can be used to initialize parent contracts.
                   *
                   * Similar to `reinitializer(1)`, except that functions marked with `initializer` can be nested in the context of a
                   * constructor.
                   *
                   * Emits an {Initialized} event.
                   */
                  modifier initializer() {
                      bool isTopLevelCall = !_initializing;
                      require(
                          (isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
                          "Initializable: contract is already initialized"
                      );
                      _initialized = 1;
                      if (isTopLevelCall) {
                          _initializing = true;
                      }
                      _;
                      if (isTopLevelCall) {
                          _initializing = false;
                          emit Initialized(1);
                      }
                  }
                  /**
                   * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
                   * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
                   * used to initialize parent contracts.
                   *
                   * A reinitializer may be used after the original initialization step. This is essential to configure modules that
                   * are added through upgrades and that require initialization.
                   *
                   * When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer`
                   * cannot be nested. If one is invoked in the context of another, execution will revert.
                   *
                   * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
                   * a contract, executing them in the right order is up to the developer or operator.
                   *
                   * WARNING: setting the version to 255 will prevent any future reinitialization.
                   *
                   * Emits an {Initialized} event.
                   */
                  modifier reinitializer(uint8 version) {
                      require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
                      _initialized = version;
                      _initializing = true;
                      _;
                      _initializing = false;
                      emit Initialized(version);
                  }
                  /**
                   * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
                   * {initializer} and {reinitializer} modifiers, directly or indirectly.
                   */
                  modifier onlyInitializing() {
                      require(_initializing, "Initializable: contract is not initializing");
                      _;
                  }
                  /**
                   * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
                   * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
                   * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
                   * through proxies.
                   *
                   * Emits an {Initialized} event the first time it is successfully executed.
                   */
                  function _disableInitializers() internal virtual {
                      require(!_initializing, "Initializable: contract is initializing");
                      if (_initialized != type(uint8).max) {
                          _initialized = type(uint8).max;
                          emit Initialized(type(uint8).max);
                      }
                  }
                  /**
                   * @dev Returns the highest version that has been initialized. See {reinitializer}.
                   */
                  function _getInitializedVersion() internal view returns (uint8) {
                      return _initialized;
                  }
                  /**
                   * @dev Returns `true` if the contract is currently initializing. See {onlyInitializing}.
                   */
                  function _isInitializing() internal view returns (bool) {
                      return _initializing;
                  }
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts (last updated v4.9.0) (security/ReentrancyGuard.sol)
              pragma solidity ^0.8.0;
              import "../proxy/utils/Initializable.sol";
              /**
               * @dev Contract module that helps prevent reentrant calls to a function.
               *
               * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
               * available, which can be applied to functions to make sure there are no nested
               * (reentrant) calls to them.
               *
               * Note that because there is a single `nonReentrant` guard, functions marked as
               * `nonReentrant` may not call one another. This can be worked around by making
               * those functions `private`, and then adding `external` `nonReentrant` entry
               * points to them.
               *
               * TIP: If you would like to learn more about reentrancy and alternative ways
               * to protect against it, check out our blog post
               * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
               */
              abstract contract ReentrancyGuardUpgradeable is Initializable {
                  // Booleans are more expensive than uint256 or any type that takes up a full
                  // word because each write operation emits an extra SLOAD to first read the
                  // slot's contents, replace the bits taken up by the boolean, and then write
                  // back. This is the compiler's defense against contract upgrades and
                  // pointer aliasing, and it cannot be disabled.
                  // The values being non-zero value makes deployment a bit more expensive,
                  // but in exchange the refund on every call to nonReentrant will be lower in
                  // amount. Since refunds are capped to a percentage of the total
                  // transaction's gas, it is best to keep them low in cases like this one, to
                  // increase the likelihood of the full refund coming into effect.
                  uint256 private constant _NOT_ENTERED = 1;
                  uint256 private constant _ENTERED = 2;
                  uint256 private _status;
                  function __ReentrancyGuard_init() internal onlyInitializing {
                      __ReentrancyGuard_init_unchained();
                  }
                  function __ReentrancyGuard_init_unchained() internal onlyInitializing {
                      _status = _NOT_ENTERED;
                  }
                  /**
                   * @dev Prevents a contract from calling itself, directly or indirectly.
                   * Calling a `nonReentrant` function from another `nonReentrant`
                   * function is not supported. It is possible to prevent this from happening
                   * by making the `nonReentrant` function external, and making it call a
                   * `private` function that does the actual work.
                   */
                  modifier nonReentrant() {
                      _nonReentrantBefore();
                      _;
                      _nonReentrantAfter();
                  }
                  function _nonReentrantBefore() private {
                      // On the first call to nonReentrant, _status will be _NOT_ENTERED
                      require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
                      // Any calls to nonReentrant after this point will fail
                      _status = _ENTERED;
                  }
                  function _nonReentrantAfter() private {
                      // By storing the original value once again, a refund is triggered (see
                      // https://eips.ethereum.org/EIPS/eip-2200)
                      _status = _NOT_ENTERED;
                  }
                  /**
                   * @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
                   * `nonReentrant` function in the call stack.
                   */
                  function _reentrancyGuardEntered() internal view returns (bool) {
                      return _status == _ENTERED;
                  }
                  /**
                   * @dev This empty reserved space is put in place to allow future versions to add new
                   * variables without shifting down storage in the inheritance chain.
                   * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                   */
                  uint256[49] private __gap;
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)
              pragma solidity ^0.8.1;
              /**
               * @dev Collection of functions related to the address type
               */
              library AddressUpgradeable {
                  /**
                   * @dev Returns true if `account` is a contract.
                   *
                   * [IMPORTANT]
                   * ====
                   * It is unsafe to assume that an address for which this function returns
                   * false is an externally-owned account (EOA) and not a contract.
                   *
                   * Among others, `isContract` will return false for the following
                   * types of addresses:
                   *
                   *  - an externally-owned account
                   *  - a contract in construction
                   *  - an address where a contract will be created
                   *  - an address where a contract lived, but was destroyed
                   *
                   * Furthermore, `isContract` will also return true if the target contract within
                   * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
                   * which only has an effect at the end of a transaction.
                   * ====
                   *
                   * [IMPORTANT]
                   * ====
                   * You shouldn't rely on `isContract` to protect against flash loan attacks!
                   *
                   * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
                   * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
                   * constructor.
                   * ====
                   */
                  function isContract(address account) internal view returns (bool) {
                      // This method relies on extcodesize/address.code.length, which returns 0
                      // for contracts in construction, since the code is only stored at the end
                      // of the constructor execution.
                      return account.code.length > 0;
                  }
                  /**
                   * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                   * `recipient`, forwarding all available gas and reverting on errors.
                   *
                   * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                   * of certain opcodes, possibly making contracts go over the 2300 gas limit
                   * imposed by `transfer`, making them unable to receive funds via
                   * `transfer`. {sendValue} removes this limitation.
                   *
                   * https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                   *
                   * IMPORTANT: because control is transferred to `recipient`, care must be
                   * taken to not create reentrancy vulnerabilities. Consider using
                   * {ReentrancyGuard} or the
                   * https://solidity.readthedocs.io/en/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                   */
                  function sendValue(address payable recipient, uint256 amount) internal {
                      require(address(this).balance >= amount, "Address: insufficient balance");
                      (bool success, ) = recipient.call{value: amount}("");
                      require(success, "Address: unable to send value, recipient may have reverted");
                  }
                  /**
                   * @dev Performs a Solidity function call using a low level `call`. A
                   * plain `call` is an unsafe replacement for a function call: use this
                   * function instead.
                   *
                   * If `target` reverts with a revert reason, it is bubbled up by this
                   * function (like regular Solidity function calls).
                   *
                   * Returns the raw returned data. To convert to the expected return value,
                   * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                   *
                   * Requirements:
                   *
                   * - `target` must be a contract.
                   * - calling `target` with `data` must not revert.
                   *
                   * _Available since v3.1._
                   */
                  function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                      return functionCallWithValue(target, data, 0, "Address: low-level call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                   * `errorMessage` as a fallback revert reason when `target` reverts.
                   *
                   * _Available since v3.1._
                   */
                  function functionCall(
                      address target,
                      bytes memory data,
                      string memory errorMessage
                  ) internal returns (bytes memory) {
                      return functionCallWithValue(target, data, 0, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but also transferring `value` wei to `target`.
                   *
                   * Requirements:
                   *
                   * - the calling contract must have an ETH balance of at least `value`.
                   * - the called Solidity function must be `payable`.
                   *
                   * _Available since v3.1._
                   */
                  function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
                      return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                   * with `errorMessage` as a fallback revert reason when `target` reverts.
                   *
                   * _Available since v3.1._
                   */
                  function functionCallWithValue(
                      address target,
                      bytes memory data,
                      uint256 value,
                      string memory errorMessage
                  ) internal returns (bytes memory) {
                      require(address(this).balance >= value, "Address: insufficient balance for call");
                      (bool success, bytes memory returndata) = target.call{value: value}(data);
                      return verifyCallResultFromTarget(target, success, returndata, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but performing a static call.
                   *
                   * _Available since v3.3._
                   */
                  function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                      return functionStaticCall(target, data, "Address: low-level static call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                   * but performing a static call.
                   *
                   * _Available since v3.3._
                   */
                  function functionStaticCall(
                      address target,
                      bytes memory data,
                      string memory errorMessage
                  ) internal view returns (bytes memory) {
                      (bool success, bytes memory returndata) = target.staticcall(data);
                      return verifyCallResultFromTarget(target, success, returndata, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but performing a delegate call.
                   *
                   * _Available since v3.4._
                   */
                  function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                      return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                   * but performing a delegate call.
                   *
                   * _Available since v3.4._
                   */
                  function functionDelegateCall(
                      address target,
                      bytes memory data,
                      string memory errorMessage
                  ) internal returns (bytes memory) {
                      (bool success, bytes memory returndata) = target.delegatecall(data);
                      return verifyCallResultFromTarget(target, success, returndata, errorMessage);
                  }
                  /**
                   * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
                   * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
                   *
                   * _Available since v4.8._
                   */
                  function verifyCallResultFromTarget(
                      address target,
                      bool success,
                      bytes memory returndata,
                      string memory errorMessage
                  ) internal view returns (bytes memory) {
                      if (success) {
                          if (returndata.length == 0) {
                              // only check isContract if the call was successful and the return data is empty
                              // otherwise we already know that it was a contract
                              require(isContract(target), "Address: call to non-contract");
                          }
                          return returndata;
                      } else {
                          _revert(returndata, errorMessage);
                      }
                  }
                  /**
                   * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
                   * revert reason or using the provided one.
                   *
                   * _Available since v4.3._
                   */
                  function verifyCallResult(
                      bool success,
                      bytes memory returndata,
                      string memory errorMessage
                  ) internal pure returns (bytes memory) {
                      if (success) {
                          return returndata;
                      } else {
                          _revert(returndata, errorMessage);
                      }
                  }
                  function _revert(bytes memory returndata, string memory errorMessage) private pure {
                      // Look for revert reason and bubble it up if present
                      if (returndata.length > 0) {
                          // The easiest way to bubble the revert reason is using memory via assembly
                          /// @solidity memory-safe-assembly
                          assembly {
                              let returndata_size := mload(returndata)
                              revert(add(32, returndata), returndata_size)
                          }
                      } else {
                          revert(errorMessage);
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
              pragma solidity ^0.8.0;
              import "../proxy/utils/Initializable.sol";
              /**
               * @dev Provides information about the current execution context, including the
               * sender of the transaction and its data. While these are generally available
               * via msg.sender and msg.data, they should not be accessed in such a direct
               * manner, since when dealing with meta-transactions the account sending and
               * paying for execution may not be the actual sender (as far as an application
               * is concerned).
               *
               * This contract is only required for intermediate, library-like contracts.
               */
              abstract contract ContextUpgradeable is Initializable {
                  function __Context_init() internal onlyInitializing {
                  }
                  function __Context_init_unchained() internal onlyInitializing {
                  }
                  function _msgSender() internal view virtual returns (address) {
                      return msg.sender;
                  }
                  function _msgData() internal view virtual returns (bytes calldata) {
                      return msg.data;
                  }
                  /**
                   * @dev This empty reserved space is put in place to allow future versions to add new
                   * variables without shifting down storage in the inheritance chain.
                   * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                   */
                  uint256[50] private __gap;
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              pragma abicoder v2;
              import "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
              import "@openzeppelin/contracts-upgradeable/security/ReentrancyGuardUpgradeable.sol";
              import "./UnxswapRouter.sol";
              import "./UnxswapV3Router.sol";
              import "./interfaces/IWETH.sol";
              import "./interfaces/IAdapter.sol";
              import "./interfaces/IApproveProxy.sol";
              import "./interfaces/IWNativeRelayer.sol";
              import "./interfaces/IXBridge.sol";
              import "./libraries/Permitable.sol";
              import "./libraries/PMMLib.sol";
              import "./libraries/CommissionLib.sol";
              import "./libraries/EthReceiver.sol";
              import "./libraries/WrapETHSwap.sol";
              import "./libraries/CommonUtils.sol";
              import "./storage/DexRouterStorage.sol";
              /// @title DexRouterV1
              /// @notice Entrance of Split trading in Dex platform
              /// @dev Entrance of Split trading in Dex platform
              contract DexRouter is
                  OwnableUpgradeable,
                  ReentrancyGuardUpgradeable,
                  Permitable,
                  EthReceiver,
                  UnxswapRouter,
                  UnxswapV3Router,
                  DexRouterStorage,
                  WrapETHSwap,
                  CommissionLib
              {
                  using UniversalERC20 for IERC20;
                  struct BaseRequest {
                      uint256 fromToken;
                      address toToken;
                      uint256 fromTokenAmount;
                      uint256 minReturnAmount;
                      uint256 deadLine;
                  }
                  struct RouterPath {
                      address[] mixAdapters;
                      address[] assetTo;
                      uint256[] rawData;
                      bytes[] extraData;
                      uint256 fromToken;
                  }
                  /// @notice Initializes the contract with necessary setup for ownership and reentrancy protection.
                  /// @dev This function serves as a constructor for upgradeable contracts and should be called
                  /// through a proxy during the initial deployment. It initializes inherited contracts
                  /// such as `OwnableUpgradeable` and `ReentrancyGuardUpgradeable` to set up the contract's owner
                  /// and reentrancy guard.
                  function initialize() public initializer {
                      __Ownable_init();
                      __ReentrancyGuard_init();
                  }
                  //-------------------------------
                  //------- Events ----------------
                  //-------------------------------
                  /// @notice Emitted when a priority address status is updated.
                  /// @param priorityAddress The address whose priority status has been changed.
                  /// @param valid A boolean indicating the new status of the priority address.
                  /// True means the address is now considered a priority address, and false means it is not.
                  event PriorityAddressChanged(address priorityAddress, bool valid);
                  /// @notice Emitted when the admin address of the contract is changed.
                  /// @param newAdmin The address of the new admin.
                  event AdminChanged(address newAdmin);
                  //-------------------------------
                  //------- Modifier --------------
                  //-------------------------------
                  /// @notice Ensures a function is called before a specified deadline.
                  /// @param deadLine The UNIX timestamp deadline.
                  modifier isExpired(uint256 deadLine) {
                      require(deadLine >= block.timestamp, "Route: expired");
                      _;
                  }
                  /// @notice Restricts function access to addresses marked as priority.
                  /// Ensures that only addresses designated with specific privileges can execute the function.
                  modifier onlyPriorityAddress() {
                      require(priorityAddresses[msg.sender] == true, "only priority");
                      _;
                  }
                  //-------------------------------
                  //------- Internal Functions ----
                  //-------------------------------
                  /// @notice Executes multiple adapters for a transaction pair.
                  /// @param payer The address of the payer.
                  /// @param to The address of the receiver.
                  /// @param batchAmount The amount to be transferred in each batch.
                  /// @param path The routing path for the swap.
                  /// @param noTransfer A flag to indicate whether the token transfer should be skipped.
                  /// @dev It includes checks for the total weight of the paths and executes the swapping through the adapters.
                  function _exeForks(
                      address payer,
                      address to,
                      uint256 batchAmount,
                      RouterPath calldata path,
                      bool noTransfer
                  ) private {
                      address fromToken = _bytes32ToAddress(path.fromToken);
                      // fix post audit DRW-01: lack of check on Weights
                      uint256 totalWeight;
                      // execute multiple Adapters for a transaction pair
                      uint256 pathLength = path.mixAdapters.length;
                      for (uint256 i = 0; i < pathLength; ) {
                          bytes32 rawData = bytes32(path.rawData[i]);
                          address poolAddress;
                          bool reserves;
                          uint256 weight;
                          assembly {
                              poolAddress := and(rawData, _ADDRESS_MASK)
                              reserves := and(rawData, _REVERSE_MASK)
                              weight := shr(160, and(rawData, _WEIGHT_MASK))
                          }
                          totalWeight += weight;
                          if (i == pathLength - 1) {
                              require(
                                  totalWeight <= 10_000,
                                  "totalWeight can not exceed 10000 limit"
                              );
                          }
                          if (!noTransfer) {
                              uint256 _fromTokenAmount = weight == 10_000
                                  ? batchAmount
                                  : (batchAmount * weight) / 10_000;
                              _transferInternal(
                                  payer,
                                  path.assetTo[i],
                                  fromToken,
                                  _fromTokenAmount
                              );
                          }
                          if (reserves) {
                              IAdapter(path.mixAdapters[i]).sellQuote(
                                  to,
                                  poolAddress,
                                  path.extraData[i]
                              );
                          } else {
                              IAdapter(path.mixAdapters[i]).sellBase(
                                  to,
                                  poolAddress,
                                  path.extraData[i]
                              );
                          }
                          unchecked {
                              ++i;
                          }
                      }
                  }
                  /// @notice Executes a series of swaps or operations defined by a set of routing paths, potentially across different protocols or pools.
                  /// @param payer The address providing the tokens for the swap.
                  /// @param receiver The address receiving the output tokens.
                  /// @param isToNative Indicates whether the final asset should be converted to the native blockchain asset (e.g., ETH).
                  /// @param batchAmount The total amount of the input token to be swapped.
                  /// @param hops An array of RouterPath structures, each defining a segment of the swap route.
                  /// @dev This function manages complex swap routes that might involve multiple hops through different liquidity pools or swapping protocols.
                  /// It iterates through the provided `hops`, executing each segment of the route in sequence.
                  function _exeHop(
                      address payer,
                      address receiver,
                      bool isToNative,
                      uint256 batchAmount,
                      RouterPath[] calldata hops
                  ) private {
                      address fromToken = _bytes32ToAddress(hops[0].fromToken);
                      bool toNext;
                      bool noTransfer;
                      // execute hop
                      uint256 hopLength = hops.length;
                      for (uint256 i = 0; i < hopLength; ) {
                          if (i > 0) {
                              fromToken = _bytes32ToAddress(hops[i].fromToken);
                              batchAmount = IERC20(fromToken).universalBalanceOf(
                                  address(this)
                              );
                              payer = address(this);
                          }
                          address to = address(this);
                          if (i == hopLength - 1 && !isToNative) {
                              to = receiver;
                          } else if (i < hopLength - 1 && hops[i + 1].assetTo.length == 1) {
                              to = hops[i + 1].assetTo[0];
                              toNext = true;
                          } else {
                              toNext = false;
                          }
                          // 3.2 execute forks
                          _exeForks(payer, to, batchAmount, hops[i], noTransfer);
                          noTransfer = toNext;
                          unchecked {
                              ++i;
                          }
                      }
                  }
                  /// @notice Transfers tokens internally within the contract.
                  /// @param payer The address of the payer.
                  /// @param to The address of the receiver.
                  /// @param token The address of the token to be transferred.
                  /// @param amount The amount of tokens to be transferred.
                  /// @dev Handles the transfer of ERC20 tokens or native tokens within the contract.
                  function _transferInternal(
                      address payer,
                      address to,
                      address token,
                      uint256 amount
                  ) private {
                      if (payer == address(this)) {
                          SafeERC20.safeTransfer(IERC20(token), to, amount);
                      } else {
                          IApproveProxy(_APPROVE_PROXY).claimTokens(token, payer, to, amount);
                      }
                  }
                  /// @notice Transfers the specified token to the user.
                  /// @param token The address of the token to be transferred.
                  /// @param to The address of the receiver.
                  /// @dev Handles the withdrawal of tokens to the user, converting WETH to ETH if necessary.
                  function _transferTokenToUser(address token, address to) private {
                      if ((IERC20(token).isETH())) {
                          uint256 wethBal = IERC20(address(uint160(_WETH))).balanceOf(
                              address(this)
                          );
                          if (wethBal > 0) {
                              IWETH(address(uint160(_WETH))).transfer(
                                  _WNATIVE_RELAY,
                                  wethBal
                              );
                              IWNativeRelayer(_WNATIVE_RELAY).withdraw(wethBal);
                          }
                          if (to != address(this)) {
                              uint256 ethBal = address(this).balance;
                              if (ethBal > 0) {
                                  (bool success, ) = payable(to).call{value: ethBal}("");
                                  require(success, "transfer native token failed");
                              }
                          }
                      } else {
                          if (to != address(this)) {
                              uint256 bal = IERC20(token).balanceOf(address(this));
                              if (bal > 0) {
                                  SafeERC20.safeTransfer(IERC20(token), to, bal);
                              }
                          }
                      }
                  }
                  /// @notice Converts a uint256 value into an address.
                  /// @param param The uint256 value to be converted.
                  /// @return result The address obtained from the conversion.
                  /// @dev This function is used to extract an address from a uint256,
                  /// typically used when dealing with low-level data operations or when addresses are packed into larger data types.
                  function _bytes32ToAddress(
                      uint256 param
                  ) private pure returns (address result) {
                      assembly {
                          result := and(param, _ADDRESS_MASK)
                      }
                  }
                  /// @notice Executes a complex swap based on provided parameters and paths.
                  /// @param baseRequest Basic swap details including tokens, amounts, and deadline.
                  /// @param batchesAmount Amounts for each swap batch.
                  /// @param batches Detailed swap paths for execution.
                  /// @param payer Address providing the tokens.
                  /// @param receiver Address receiving the swapped tokens.
                  /// @return returnAmount Total received tokens from the swap.
                  function _smartSwapInternal(
                      BaseRequest memory baseRequest,
                      uint256[] memory batchesAmount,
                      RouterPath[][] calldata batches,
                      address payer,
                      address receiver
                  ) private returns (uint256 returnAmount) {
                      // 1. transfer from token in
                      BaseRequest memory _baseRequest = baseRequest;
                      require(
                          _baseRequest.fromTokenAmount > 0,
                          "Route: fromTokenAmount must be > 0"
                      );
                      address fromToken = _bytes32ToAddress(_baseRequest.fromToken);
                      returnAmount = IERC20(_baseRequest.toToken).universalBalanceOf(
                          receiver
                      );
                      // In order to deal with ETH/WETH transfer rules in a unified manner,
                      // we do not need to judge according to fromToken.
                      if (UniversalERC20.isETH(IERC20(fromToken))) {
                          IWETH(address(uint160(_WETH))).deposit{
                              value: _baseRequest.fromTokenAmount
                          }();
                          payer = address(this);
                      }
                      // 2. check total batch amount
                      {
                          // avoid stack too deep
                          uint256 totalBatchAmount;
                          for (uint256 i = 0; i < batchesAmount.length; ) {
                              totalBatchAmount += batchesAmount[i];
                              unchecked {
                                  ++i;
                              }
                          }
                          require(
                              totalBatchAmount <= _baseRequest.fromTokenAmount,
                              "Route: number of batches should be <= fromTokenAmount"
                          );
                      }
                      // 4. execute batch
                      // check length, fix DRW-02: LACK OF LENGTH CHECK ON BATATCHES
                      require(batchesAmount.length == batches.length, "length mismatch");
                      for (uint256 i = 0; i < batches.length; ) {
                          // execute hop, if the whole swap replacing by pmm fails, the funds will return to dexRouter
                          _exeHop(
                              payer,
                              receiver,
                              IERC20(_baseRequest.toToken).isETH(),
                              batchesAmount[i],
                              batches[i]
                          );
                          unchecked {
                              ++i;
                          }
                      }
                      // 5. transfer tokens to user
                      _transferTokenToUser(_baseRequest.toToken, receiver);
                      // 6. check minReturnAmount
                      returnAmount =
                          IERC20(_baseRequest.toToken).universalBalanceOf(receiver) -
                          returnAmount;
                      require(
                          returnAmount >= _baseRequest.minReturnAmount,
                          "Min return not reached"
                      );
                      emit OrderRecord(
                          fromToken,
                          _baseRequest.toToken,
                          tx.origin,
                          _baseRequest.fromTokenAmount,
                          returnAmount
                      );
                      return returnAmount;
                  }
                  //-------------------------------
                  //------- Admin functions -------
                  //-------------------------------
                  /// @notice Updates the priority status of an address, allowing or disallowing it from performing certain actions.
                  /// @param _priorityAddress The address whose priority status is to be updated.
                  /// @param valid A boolean indicating whether the address should be marked as a priority (true) or not (false).
                  /// @dev This function can only be called by the contract owner or another authorized entity.
                  /// It is typically used to grant or revoke special permissions to certain addresses.
                  function setPriorityAddress(address _priorityAddress, bool valid) external {
                      require(msg.sender == admin || msg.sender == owner(), "na");
                      priorityAddresses[_priorityAddress] = valid;
                      emit PriorityAddressChanged(_priorityAddress, valid);
                  }
                  /// @notice Assigns a new admin address for the protocol.
                  /// @param _newAdmin The address to be granted admin privileges.
                  /// @dev Only the current owner or existing admin can assign a new admin, ensuring secure management of protocol permissions.
                  /// Changing the admin address is a critical operation that should be performed with caution.
                  function setProtocolAdmin(address _newAdmin) external {
                      require(msg.sender == admin || msg.sender == owner(), "na");
                      admin = _newAdmin;
                      emit AdminChanged(_newAdmin);
                  }
                  //-------------------------------
                  //------- Users Functions -------
                  //-------------------------------
                  /// @notice Executes a smart swap operation through the XBridge, identified by a specific order ID.
                  /// @param orderId The unique identifier for the swap order, facilitating tracking and reference.
                  /// @param baseRequest Contains essential parameters for the swap, such as source and destination tokens, amount, minimum return, and deadline.
                  /// @param batchesAmount Array of amounts for each batch in the swap, allowing for split operations across different routes or pools.
                  /// @param batches Detailed paths for each swap batch, including adapters and target assets.
                  /// @param extraData Additional data required for executing the swap, which may include specific instructions or parameters for adapters.
                  /// @return returnAmount The total amount of the destination token received from the swap.
                  /// @dev This function allows for complex swap operations across different liquidity sources or protocols, initiated via the XBridge.
                  /// It's designed to be called by authorized addresses, ensuring that the swap meets predefined criteria and security measures.
                  function smartSwapByOrderIdByXBridge(
                      uint256 orderId,
                      BaseRequest calldata baseRequest,
                      uint256[] calldata batchesAmount,
                      RouterPath[][] calldata batches,
                      PMMLib.PMMSwapRequest[] calldata extraData
                  )
                      external
                      payable
                      isExpired(baseRequest.deadLine)
                      nonReentrant
                      onlyPriorityAddress
                      returns (uint256 returnAmount)
                  {
                      emit SwapOrderId(orderId);
                      (address payer, address receiver) = IXBridge(msg.sender)
                          .payerReceiver();
                      require(receiver != address(0), "not address(0)");
                      return
                          _smartSwapTo(payer, receiver, baseRequest, batchesAmount, batches);
                  }
                  /// @notice Executes a token swap using Unxswap protocol via XBridge for a specific order ID.
                  /// @param srcToken The source token's address to be swapped.
                  /// @param amount The amount of the source token to be swapped.
                  /// @param minReturn The minimum acceptable return amount of destination tokens to ensure the swap is executed within acceptable slippage.
                  /// @param pools Pool identifiers used for the swap, allowing for route optimization.
                  /// @return returnAmount The amount of destination tokens received from the swap.
                  /// @dev This function is designed to facilitate cross-protocol swaps through the XBridge,
                  /// enabling swaps that adhere to specific routing paths defined by the pools parameter.
                  /// It is accessible only to priority addresses, ensuring controlled access and execution.
                  function unxswapByOrderIdByXBridge(
                      uint256 srcToken,
                      uint256 amount,
                      uint256 minReturn,
                      // solhint-disable-next-line no-unused-vars
                      bytes32[] calldata pools
                  ) external payable onlyPriorityAddress returns (uint256 returnAmount) {
                      emit SwapOrderId((srcToken & _ORDER_ID_MASK) >> 160);
                      (address payer, address receiver) = IXBridge(msg.sender)
                          .payerReceiver();
                      require(receiver != address(0), "not address(0)");
                      return _unxswapTo(srcToken, amount, minReturn, payer, receiver, pools);
                  }
                  /// @notice Executes a token swap using the Uniswap V3 protocol through the XBridge, specifically catering to priority addresses.
                  /// @param receiver The address that will receive the swap funds.
                  /// @param amount The amount of the source token to be swapped.
                  /// @param minReturn The minimum acceptable amount of tokens to be received from the swap. This parameter ensures the swap does not proceed if the return is below the specified threshold, guarding against excessive slippage.
                  /// @param pools An array of pool identifiers used to define the swap route in the Uniswap V3 pools.
                  /// @return returnAmount The amount of tokens received from the swap.
                  /// @dev This function is exclusively accessible to priority addresses and is responsible for executing swaps on Uniswap V3 through the XBridge interface. It ensures that the swap meets the criteria set by the parameters and utilizes the _uniswapV3Swap internal function to perform the actual swap.
                  function uniswapV3SwapToByXBridge(
                      uint256 receiver,
                      uint256 amount,
                      uint256 minReturn,
                      uint256[] calldata pools
                  ) external payable onlyPriorityAddress returns (uint256 returnAmount) {
                      emit SwapOrderId((receiver & _ORDER_ID_MASK) >> 160);
                      (address payer, address receiver_) = IXBridge(msg.sender)
                          .payerReceiver();
                      require(receiver_ != address(0), "not address(0)");
                      return
                          _uniswapV3SwapTo(
                              payer,
                              uint160(receiver_),
                              amount,
                              minReturn,
                              pools
                          );
                  }
                  /// @notice Executes a smart swap based on the given order ID, supporting complex multi-path swaps.
                  /// @param orderId The unique identifier for the swap order, facilitating tracking and reference.
                  /// @param baseRequest Struct containing the base parameters for the swap, including the source and destination tokens, amount, minimum return, and deadline.
                  /// @param batchesAmount An array specifying the amount to be swapped in each batch, allowing for split operations.
                  /// @param batches An array of RouterPath structs defining the routing paths for each batch, enabling swaps through multiple protocols or liquidity pools.
                  /// @param extraData Additional data required for some swaps, accommodating special instructions or parameters necessary for executing the swap.
                  /// @return returnAmount The total amount of destination tokens received from executing the swap.
                  /// @dev This function orchestrates a swap operation that may involve multiple steps, routes, or protocols based on the provided parameters.
                  /// It's designed to ensure flexibility and efficiency in finding the best swap paths.
                  function smartSwapByOrderId(
                      uint256 orderId,
                      BaseRequest calldata baseRequest,
                      uint256[] calldata batchesAmount,
                      RouterPath[][] calldata batches,
                      PMMLib.PMMSwapRequest[] calldata extraData
                  )
                      external
                      payable
                      isExpired(baseRequest.deadLine)
                      nonReentrant
                      returns (uint256 returnAmount)
                  {
                      emit SwapOrderId(orderId);
                      return
                          _smartSwapTo(
                              msg.sender,
                              msg.sender,
                              baseRequest,
                              batchesAmount,
                              batches
                          );
                  }
                  /// @notice Executes a token swap using the Unxswap protocol based on a specified order ID.
                  /// @param srcToken The source token involved in the swap.
                  /// @param amount The amount of the source token to be swapped.
                  /// @param minReturn The minimum amount of tokens expected to be received to ensure the swap does not proceed under unfavorable conditions.
                  /// @param pools An array of pool identifiers specifying the pools to use for the swap, allowing for optimized routing.
                  /// @return returnAmount The amount of destination tokens received from the swap.
                  /// @dev This function allows users to perform token swaps based on predefined orders, leveraging the Unxswap protocol's liquidity pools. It ensures that the swap meets the user's specified minimum return criteria, enhancing trade efficiency and security.
                  function unxswapByOrderId(
                      uint256 srcToken,
                      uint256 amount,
                      uint256 minReturn,
                      // solhint-disable-next-line no-unused-vars
                      bytes32[] calldata pools
                  ) external payable returns (uint256 returnAmount) {
                      emit SwapOrderId((srcToken & _ORDER_ID_MASK) >> 160);
                      return
                          _unxswapTo(
                              srcToken,
                              amount,
                              minReturn,
                              msg.sender,
                              msg.sender,
                              pools
                          );
                  }
                  /// @notice Executes a swap tailored for investment purposes, adjusting swap amounts based on the contract's balance.
                  /// @param baseRequest Struct containing essential swap parameters like source and destination tokens, amounts, and deadline.
                  /// @param batchesAmount Array indicating how much of the source token to swap in each batch, facilitating diversified investments.
                  /// @param batches Detailed routing information for executing the swap across different paths or protocols.
                  /// @param extraData Additional data for swaps, supporting protocol-specific requirements.
                  /// @param to The address where the swapped tokens will be sent, typically an investment contract or pool.
                  /// @return returnAmount The total amount of destination tokens received, ready for investment.
                  /// @dev This function is designed for scenarios where investments are made in batches or through complex paths to optimize returns. Adjustments are made based on the contract's current token balance to ensure precise allocation.
                  function smartSwapByInvest(
                      BaseRequest calldata baseRequest,
                      uint256[] calldata batchesAmount,
                      RouterPath[][] calldata batches,
                      PMMLib.PMMSwapRequest[] calldata extraData,
                      address to
                  )
                      external
                      payable
                      isExpired(baseRequest.deadLine)
                      nonReentrant
                      returns (uint256 returnAmount)
                  {
                      address fromToken = _bytes32ToAddress(baseRequest.fromToken);
                      require(fromToken != _ETH, "Invalid source token");
                      uint256 amount = IERC20(fromToken).balanceOf(address(this));
                      BaseRequest memory newBaseRequest = BaseRequest({
                          fromToken: baseRequest.fromToken,
                          toToken: baseRequest.toToken,
                          fromTokenAmount: amount,
                          minReturnAmount: baseRequest.minReturnAmount,
                          deadLine: baseRequest.deadLine
                      });
                      uint256[] memory newBatchesAmount = new uint256[](batchesAmount.length);
                      for (uint256 i = 0; i < batchesAmount.length; ) {
                          newBatchesAmount[i] =
                              (batchesAmount[i] * amount) /
                              baseRequest.fromTokenAmount;
                          unchecked {
                              ++i;
                          }
                      }
                      returnAmount = _smartSwapInternal(
                          newBaseRequest,
                          newBatchesAmount,
                          batches,
                          address(this),
                          to
                      );
                  }
                  /// @notice Executes a Uniswap V3 swap after obtaining a permit, allowing the approval of token spending and swap execution in a single transaction.
                  /// @param receiver The address that will receive the funds from the swap.
                  /// @param srcToken The token that will be swapped.
                  /// @param amount The amount of source tokens to be swapped.
                  /// @param minReturn The minimum acceptable amount of tokens to receive from the swap, guarding against slippage.
                  /// @param pools An array of Uniswap V3 pool identifiers, specifying the pools to be used for the swap.
                  /// @param permit A signed permit message that allows the router to spend the source tokens without requiring a separate `approve` transaction.
                  /// @return returnAmount The amount of tokens received from the swap.
                  /// @dev This function first utilizes the `_permit` function to approve token spending, then proceeds to execute the swap through `_uniswapV3Swap`. It's designed to streamline transactions by combining token approval and swap execution into a single operation.
                  function uniswapV3SwapToWithPermit(
                      uint256 receiver,
                      IERC20 srcToken,
                      uint256 amount,
                      uint256 minReturn,
                      uint256[] calldata pools,
                      bytes calldata permit
                  ) external returns (uint256 returnAmount) {
                      emit SwapOrderId((receiver & _ORDER_ID_MASK) >> 160);
                      _permit(address(srcToken), permit);
                      return _uniswapV3SwapTo(msg.sender, receiver, amount, minReturn, pools);
                  }
                  /// @notice Executes a swap using the Uniswap V3 protocol.
                  /// @param receiver The address that will receive the swap funds.
                  /// @param amount The amount of the source token to be swapped.
                  /// @param minReturn The minimum acceptable amount of tokens to receive from the swap, guarding against excessive slippage.
                  /// @param pools An array of pool identifiers used to define the swap route within Uniswap V3.
                  /// @return returnAmount The amount of tokens received after the completion of the swap.
                  /// @dev This function wraps and unwraps ETH as required, ensuring the transaction only accepts non-zero `msg.value` for ETH swaps. It invokes `_uniswapV3Swap` to execute the actual swap and handles commission post-swap.
                  function uniswapV3SwapTo(
                      uint256 receiver,
                      uint256 amount,
                      uint256 minReturn,
                      uint256[] calldata pools
                  ) external payable returns (uint256 returnAmount) {
                      emit SwapOrderId((receiver & _ORDER_ID_MASK) >> 160);
                      return _uniswapV3SwapTo(msg.sender, receiver, amount, minReturn, pools);
                  }
                  function _uniswapV3SwapTo(
                      address payer,
                      uint256 receiver,
                      uint256 amount,
                      uint256 minReturn,
                      uint256[] calldata pools
                  ) internal returns (uint256 returnAmount) {
                      CommissionInfo memory commissionInfo = _getCommissionInfo();
                      (
                          address middleReceiver,
                          uint256 balanceBefore
                      ) = _doCommissionFromToken(
                              commissionInfo,
                              address(uint160(receiver)),
                              amount
                          );
                      (uint256 swappedAmount, ) = _uniswapV3Swap(
                          payer,
                          payable(middleReceiver),
                          amount,
                          minReturn,
                          pools
                      );
                      uint256 commissionAmount = _doCommissionToToken(
                          commissionInfo,
                          address(uint160(receiver)),
                          balanceBefore
                      );
                      return swappedAmount - commissionAmount;
                  }
                  /// @notice Executes a smart swap directly to a specified receiver address.
                  /// @param orderId Unique identifier for the swap order, facilitating tracking.
                  /// @param receiver Address to receive the output tokens from the swap.
                  /// @param baseRequest Contains essential parameters for the swap such as source and destination tokens, amounts, and deadline.
                  /// @param batchesAmount Array indicating amounts for each batch in the swap, allowing for split operations.
                  /// @param batches Detailed routing information for executing the swap across different paths or protocols.
                  /// @param extraData Additional data required for certain swaps, accommodating specific protocol needs.
                  /// @return returnAmount The total amount of destination tokens received from the swap.
                  /// @dev This function enables users to perform token swaps with complex routing directly to a specified address,
                  /// optimizing for best returns and accommodating specific trading strategies.
                  function smartSwapTo(
                      uint256 orderId,
                      address receiver,
                      BaseRequest calldata baseRequest,
                      uint256[] calldata batchesAmount,
                      RouterPath[][] calldata batches,
                      PMMLib.PMMSwapRequest[] calldata extraData
                  )
                      external
                      payable
                      isExpired(baseRequest.deadLine)
                      nonReentrant
                      returns (uint256 returnAmount)
                  {
                      emit SwapOrderId(orderId);
                      return
                          _smartSwapTo(
                              msg.sender,
                              receiver,
                              baseRequest,
                              batchesAmount,
                              batches
                          );
                  }
                  function _smartSwapTo(
                      address payer,
                      address receiver,
                      BaseRequest calldata baseRequest,
                      uint256[] calldata batchesAmount,
                      RouterPath[][] calldata batches
                  ) internal returns (uint256) {
                      require(receiver != address(0), "not addr(0)");
                      CommissionInfo memory commissionInfo = _getCommissionInfo();
                      (
                          address middleReceiver,
                          uint256 balanceBefore
                      ) = _doCommissionFromToken(
                              commissionInfo,
                              receiver,
                              baseRequest.fromTokenAmount
                          );
                      address _payer = payer; // avoid stack too deep
                      uint256 swappedAmount = _smartSwapInternal(
                          baseRequest,
                          batchesAmount,
                          batches,
                          _payer,
                          middleReceiver
                      );
                      uint256 commissionAmount = _doCommissionToToken(
                          commissionInfo,
                          receiver,
                          balanceBefore
                      );
                      return swappedAmount - commissionAmount;
                  }
                  /// @notice Executes a token swap using the Unxswap protocol, sending the output directly to a specified receiver.
                  /// @param srcToken The source token to be swapped.
                  /// @param amount The amount of the source token to be swapped.
                  /// @param minReturn The minimum amount of destination tokens expected from the swap, ensuring the trade does not proceed under unfavorable conditions.
                  /// @param receiver The address where the swapped tokens will be sent.
                  /// @param pools An array of pool identifiers to specify the swap route, optimizing for best rates.
                  /// @return returnAmount The total amount of destination tokens received from the swap.
                  /// @dev This function facilitates direct swaps using Unxswap, allowing users to specify custom swap routes and ensuring that the output is sent to a predetermined address. It is designed for scenarios where the user wants to directly receive the tokens in their wallet or another contract.
                  function unxswapTo(
                      uint256 srcToken,
                      uint256 amount,
                      uint256 minReturn,
                      address receiver,
                      // solhint-disable-next-line no-unused-vars
                      bytes32[] calldata pools
                  ) external payable returns (uint256 returnAmount) {
                      emit SwapOrderId((srcToken & _ORDER_ID_MASK) >> 160);
                      return
                          _unxswapTo(
                              srcToken,
                              amount,
                              minReturn,
                              msg.sender,
                              receiver,
                              pools
                          );
                  }
                  function _unxswapTo(
                      uint256 srcToken,
                      uint256 amount,
                      uint256 minReturn,
                      address payer,
                      address receiver,
                      // solhint-disable-next-line no-unused-vars
                      bytes32[] calldata pools
                  ) internal returns (uint256 returnAmount) {
                      require(receiver != address(0), "not addr(0)");
                      CommissionInfo memory commissionInfo = _getCommissionInfo();
                      (
                          address middleReceiver,
                          uint256 balanceBefore
                      ) = _doCommissionFromToken(commissionInfo, receiver, amount);
                      uint256 swappedAmount = _unxswapInternal(
                          IERC20(address(uint160(srcToken & _ADDRESS_MASK))),
                          amount,
                          minReturn,
                          pools,
                          payer,
                          middleReceiver
                      );
                      uint256 commissionAmount = _doCommissionToToken(
                          commissionInfo,
                          receiver,
                          balanceBefore
                      );
                      return swappedAmount - commissionAmount;
                  }
                  /// @notice Allows the contract owner to withdraw any tokens or native currency considered as "dust".
                  /// @param token The address of the token to withdraw, or the zero address for native currency.
                  /// @param to The address where the dust tokens or native currency should be sent.
                  /// @param amount The amount of the token or native currency to withdraw.
                  /// @dev This function is intended for recovering small amounts of tokens or native currency
                  /// left in the contract, which might not be recoverable through normal operations.
                  /// It can only be executed by the contract owner to ensure control over the contract's assets.
                  function withdrawDust(
                      address token,
                      address to,
                      uint256 amount
                  ) external onlyOwner {
                      if (token == _ETH) {
                          (bool success, bytes memory data) = payable(to).call{value: amount}(
                              ""
                          );
                          require(success, string(data));
                      } else {
                          SafeERC20.safeTransfer(IERC20(token), to, amount);
                      }
                  }
              }
              /// SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              pragma abicoder v2;
              interface IAdapter {
                  function sellBase(
                      address to,
                      address pool,
                      bytes memory data
                  ) external;
                  function sellQuote(
                      address to,
                      address pool,
                      bytes memory data
                  ) external;
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              interface IApproveProxy {
                  function isAllowedProxy(address _proxy) external view returns (bool);
                  function claimTokens(
                      address token,
                      address who,
                      address dest,
                      uint256 amount
                  ) external;
                  function tokenApprove() external view returns (address);
                  function addProxy(address) external;
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              /// @title Interface for DAI-style permits
              interface IDaiLikePermit {
                  function permit(
                      address holder,
                      address spender,
                      uint256 nonce,
                      uint256 expiry,
                      bool allowed,
                      uint8 v,
                      bytes32 r,
                      bytes32 s
                  ) external;
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              interface IERC20 {
                  event Approval(
                      address indexed owner,
                      address indexed spender,
                      uint256 value
                  );
                  event Transfer(address indexed from, address indexed to, uint256 value);
                  function name() external view returns (string memory);
                  function symbol() external view returns (string memory);
                  function decimals() external view returns (uint8);
                  function totalSupply() external view returns (uint256);
                  function balanceOf(address owner) external view returns (uint256);
                  function allowance(address owner, address spender)
                      external
                      view
                      returns (uint256);
                  function approve(address spender, uint256 value) external returns (bool);
                  function transfer(address to, uint256 value) external returns (bool);
                  function transferFrom(
                      address from,
                      address to,
                      uint256 value
                  ) external returns (bool);
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              /**
               * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
               * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
               *
               * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
               * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
               * need to send a transaction, and thus is not required to hold Ether at all.
               */
              interface IERC20Permit {
                  /**
                   * @dev Sets `value` as the allowance of `spender` over `owner`'s tokens,
                   * given `owner`'s signed approval.
                   *
                   * IMPORTANT: The same issues {IERC20-approve} has related to transaction
                   * ordering also apply here.
                   *
                   * Emits an {Approval} event.
                   *
                   * Requirements:
                   *
                   * - `spender` cannot be the zero address.
                   * - `deadline` must be a timestamp in the future.
                   * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
                   * over the EIP712-formatted function arguments.
                   * - the signature must use ``owner``'s current nonce (see {nonces}).
                   *
                   * For more information on the signature format, see the
                   * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
                   * section].
                   */
                  function permit(
                      address owner,
                      address spender,
                      uint256 value,
                      uint256 deadline,
                      uint8 v,
                      bytes32 r,
                      bytes32 s
                  ) external;
                  /**
                   * @dev Returns the current nonce for `owner`. This value must be
                   * included whenever a signature is generated for {permit}.
                   *
                   * Every successful call to {permit} increases ``owner``'s nonce by one. This
                   * prevents a signature from being used multiple times.
                   */
                  function nonces(address owner) external view returns (uint256);
                  /**
                   * @dev Returns the domain separator used in the encoding of the signature for `permit`, as defined by {EIP712}.
                   */
                  // solhint-disable-next-line func-name-mixedcase
                  function DOMAIN_SEPARATOR() external view returns (bytes32);
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              pragma abicoder v2;
              interface IUni {
                  function swapExactTokensForTokens(
                      uint256 amountIn,
                      uint256 amountOutMin,
                      address[] calldata path,
                      address to,
                      uint256 deadline
                  ) external returns (uint256[] memory amounts);
                  function swap(
                      uint256 amount0Out,
                      uint256 amount1Out,
                      address to,
                      bytes calldata data
                  ) external;
                  function getReserves()
                      external
                      view
                      returns (
                          uint112 reserve0,
                          uint112 reserve1,
                          uint32 blockTimestampLast
                      );
                  function token0() external view returns (address);
                  function token1() external view returns (address);
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              /// @title Callback for IUniswapV3PoolActions#swap
              /// @notice Any contract that calls IUniswapV3PoolActions#swap must implement this interface
              interface IUniswapV3SwapCallback {
                  /// @notice Called to `msg.sender` after executing a swap via IUniswapV3Pool#swap.
                  /// @dev In the implementation you must pay the pool tokens owed for the swap.
                  /// The caller of this method must be checked to be a UniswapV3Pool deployed by the canonical UniswapV3Factory.
                  /// amount0Delta and amount1Delta can both be 0 if no tokens were swapped.
                  /// @param amount0Delta The amount of token0 that was sent (negative) or must be received (positive) by the pool by
                  /// the end of the swap. If positive, the callback must send that amount of token0 to the pool.
                  /// @param amount1Delta The amount of token1 that was sent (negative) or must be received (positive) by the pool by
                  /// the end of the swap. If positive, the callback must send that amount of token1 to the pool.
                  /// @param data Any data passed through by the caller via the IUniswapV3PoolActions#swap call
                  function uniswapV3SwapCallback(
                      int256 amount0Delta,
                      int256 amount1Delta,
                      bytes calldata data
                  ) external;
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              pragma abicoder v2;
              interface IUniV3 {
                  function swap(
                      address recipient,
                      bool zeroForOne,
                      int256 amountSpecified,
                      uint160 sqrtPriceLimitX96,
                      bytes calldata data
                  ) external returns (int256 amount0, int256 amount1);
                  function slot0()
                      external
                      view
                      returns (
                          uint160 sqrtPriceX96,
                          int24 tick,
                          uint16 observationIndex,
                          uint16 observationCardinality,
                          uint16 observationCardinalityNext,
                          uint8 feeProtocol,
                          bool unlocked
                      );
                  function token0() external view returns (address);
                  function token1() external view returns (address);
                  /// @notice The pool's fee in hundredths of a bip, i.e. 1e-6
                  /// @return The fee
                  function fee() external view returns (uint24);
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              pragma abicoder v2;
              interface IWETH {
                  function totalSupply() external view returns (uint256);
                  function balanceOf(address account) external view returns (uint256);
                  function transfer(address recipient, uint256 amount)
                      external
                      returns (bool);
                  function allowance(address owner, address spender)
                      external
                      view
                      returns (uint256);
                  function approve(address spender, uint256 amount) external returns (bool);
                  function transferFrom(
                      address src,
                      address dst,
                      uint256 wad
                  ) external returns (bool);
                  function deposit() external payable;
                  function withdraw(uint256 wad) external;
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              pragma abicoder v2;
              interface IWNativeRelayer {
                  function withdraw(uint256 _amount) external;
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              pragma abicoder v2;
              interface IXBridge {
                  function payerReceiver() external view returns(address, address);
              }
              /// SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              /**
               * @dev Collection of functions related to the address type
               */
              library Address {
                  /**
                   * @dev Returns true if `account` is a contract.
                   *
                   * [IMPORTANT]
                   * ====
                   * It is unsafe to assume that an address for which this function returns
                   * false is an externally-owned account (EOA) and not a contract.
                   *
                   * Among others, `isContract` will return false for the following
                   * types of addresses:
                   *
                   *  - an externally-owned account
                   *  - a contract in construction
                   *  - an address where a contract will be created
                   *  - an address where a contract lived, but was destroyed
                   * ====
                   */
                  function isContract(address account) internal view returns (bool) {
                      // According to EIP-1052, 0x0 is the value returned for not-yet created accounts
                      // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
                      // for accounts without code, i.e. `keccak256('')`
                      bytes32 codehash;
                      bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          codehash := extcodehash(account)
                      }
                      return (codehash != accountHash && codehash != 0x0);
                  }
                  /**
                   * @dev Converts an `address` into `address payable`. Note that this is
                   * simply a type cast: the actual underlying value is not changed.
                   *
                   * _Available since v2.4.0._
                   */
                  function toPayable(address account)
                      internal
                      pure
                      returns (address payable)
                  {
                      return payable(account);
                  }
                  /**
                   * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                   * `recipient`, forwarding all available gas and reverting on errors.
                   *
                   * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                   * of certain opcodes, possibly making contracts go over the 2300 gas limit
                   * imposed by `transfer`, making them unable to receive funds via
                   * `transfer`. {sendValue} removes this limitation.
                   *
                   * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                   *
                   * IMPORTANT: because control is transferred to `recipient`, care must be
                   * taken to not create reentrancy vulnerabilities. Consider using
                   * {ReentrancyGuard} or the
                   * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                   *
                   * _Available since v2.4.0._
                   */
                  function sendValue(address recipient, uint256 amount) internal {
                      require(
                          address(this).balance >= amount,
                          "Address: insufficient balance"
                      );
                      // solhint-disable-next-line avoid-call-value
                      (bool success, ) = recipient.call{value: amount}("");
                      require(
                          success,
                          "Address: unable to send value, recipient may have reverted"
                      );
                  }
              }
              /// SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              import "./CommonUtils.sol";
              /// @title Base contract with common permit handling logics
              abstract contract CommissionLib is CommonUtils {
                  uint256 internal constant _COMMISSION_FEE_MASK =
                      0x000000000000ffffffffffff0000000000000000000000000000000000000000;
                  uint256 internal constant _COMMISSION_FLAG_MASK =
                      0xffffffffffff0000000000000000000000000000000000000000000000000000;
                  uint256 internal constant FROM_TOKEN_COMMISSION =
                      0x3ca20afc2aaa0000000000000000000000000000000000000000000000000000;
                  uint256 internal constant TO_TOKEN_COMMISSION =
                      0x3ca20afc2bbb0000000000000000000000000000000000000000000000000000;
                  event CommissionRecord(uint256 commissionAmount, address referrerAddress);
                  // set default vaule. can change when need.
                  uint256 public constant commissionRateLimit = 300;
                  struct CommissionInfo {
                      bool isFromTokenCommission;
                      bool isToTokenCommission;
                      uint256 commissionRate;
                      address refererAddress;
                      address token;
                  }
                  function _getCommissionInfo()
                      internal
                      pure
                      returns (CommissionInfo memory commissionInfo)
                  {
                      assembly ("memory-safe") {
                          let freePtr := mload(0x40)
                          mstore(0x40, add(freePtr, 0xa0))
                          let commissionData := calldataload(sub(calldatasize(), 0x20))
                          mstore(
                              commissionInfo,
                              eq(
                                  FROM_TOKEN_COMMISSION,
                                  and(commissionData, _COMMISSION_FLAG_MASK)
                              )
                          ) // isFromTokenCommission
                          mstore(
                              add(0x20, commissionInfo),
                              eq(
                                  TO_TOKEN_COMMISSION,
                                  and(commissionData, _COMMISSION_FLAG_MASK)
                              )
                          )
                          mstore(
                              add(0x40, commissionInfo),
                              shr(160, and(commissionData, _COMMISSION_FEE_MASK))
                          )
                          mstore(
                              add(0x60, commissionInfo),
                              and(commissionData, _ADDRESS_MASK)
                          )
                          mstore(
                              add(0x80, commissionInfo),
                              and(calldataload(sub(calldatasize(), 0x40)), _ADDRESS_MASK)
                          )
                      }
                  }
                  function _getBalanceOf(
                      address token,
                      address user
                  ) internal returns (uint256 amount) {
                      assembly {
                          function _revertWithReason(m, len) {
                              mstore(
                                  0,
                                  0x08c379a000000000000000000000000000000000000000000000000000000000
                              )
                              mstore(
                                  0x20,
                                  0x0000002000000000000000000000000000000000000000000000000000000000
                              )
                              mstore(0x40, m)
                              revert(0, len)
                          }
                          switch eq(token, _ETH)
                          case 1 {
                              amount := selfbalance()
                          }
                          default {
                              let freePtr := mload(0x40)
                              mstore(0x40, add(freePtr, 0x24))
                              mstore(
                                  freePtr,
                                  0x70a0823100000000000000000000000000000000000000000000000000000000
                              ) //balanceOf
                              mstore(add(freePtr, 0x04), user)
                              let success := staticcall(gas(), token, freePtr, 0x24, 0, 0x20)
                              if eq(success, 0) {
                                  _revertWithReason(
                                      0x000000146765742062616c616e63654f66206661696c65640000000000000000,
                                      0x58
                                  )
                              }
                              amount := mload(0x00)
                          }
                      }
                  }
                  function _doCommissionFromToken(
                      CommissionInfo memory commissionInfo,
                      address receiver,
                      uint256 inputAmount
                  ) internal returns (address, uint256) {
                      if (commissionInfo.isToTokenCommission) {
                          return (
                              address(this),
                              _getBalanceOf(commissionInfo.token, address(this))
                          );
                      }
                      if (!commissionInfo.isFromTokenCommission) {
                          return (receiver, 0);
                      }
                      assembly ("memory-safe") {
                          function _revertWithReason(m, len) {
                              mstore(
                                  0,
                                  0x08c379a000000000000000000000000000000000000000000000000000000000
                              )
                              mstore(
                                  0x20,
                                  0x0000002000000000000000000000000000000000000000000000000000000000
                              )
                              mstore(0x40, m)
                              revert(0, len)
                          }
                          let rate := mload(add(commissionInfo, 0x40))
                          if gt(rate, commissionRateLimit) {
                              _revertWithReason(
                                  0x0000001b6572726f7220636f6d6d697373696f6e2072617465206c696d697400,
                                  0x5f
                              ) //"error commission rate limit"
                          }
                          let token := mload(add(commissionInfo, 0x80))
                          let referer := mload(add(commissionInfo, 0x60))
                          let amount := div(mul(inputAmount, rate), sub(10000, rate))
                          switch eq(token, _ETH)
                          case 1 {
                              let success := call(gas(), referer, amount, 0, 0, 0, 0)
                              if eq(success, 0) {
                                  _revertWithReason(
                                      0x0000001b636f6d6d697373696f6e2077697468206574686572206572726f7200,
                                      0x5f
                                  )
                              }
                          }
                          default {
                              let freePtr := mload(0x40)
                              mstore(0x40, add(freePtr, 0x84))
                              mstore(
                                  freePtr,
                                  0x0a5ea46600000000000000000000000000000000000000000000000000000000
                              ) // claimTokens
                              mstore(add(freePtr, 0x04), token)
                              mstore(add(freePtr, 0x24), caller())
                              mstore(add(freePtr, 0x44), referer)
                              mstore(add(freePtr, 0x64), amount)
                              let success := call(
                                  gas(),
                                  _APPROVE_PROXY,
                                  0,
                                  freePtr,
                                  0x84,
                                  0,
                                  0
                              )
                              if eq(success, 0) {
                                  _revertWithReason(
                                      0x00000013636c61696d20746f6b656e73206661696c6564000000000000000000,
                                      0x57
                                  )
                              }
                          }
                          let freePtr := mload(0x40)
                          mstore(0x40, add(freePtr, 0x40))
                          mstore(freePtr, amount)
                          mstore(add(freePtr, 0x20), referer)
                          log1(
                              freePtr,
                              0x40,
                              0xffc60ee157a42f4d8edbd1897e6581a96d9ed04e44fb2ab53a47ce1eb8f2775b
                          ) //emit CommissionRecord(commissionAmount, refererAddress);
                      }
                      return (receiver, 0);
                  }
                  function _doCommissionToToken(
                      CommissionInfo memory commissionInfo,
                      address receiver,
                      uint256 balanceBefore
                  ) internal returns (uint256 amount) {
                      if (!commissionInfo.isToTokenCommission) {
                          return 0;
                      }
                      assembly ("memory-safe") {
                          function _revertWithReason(m, len) {
                              mstore(
                                  0,
                                  0x08c379a000000000000000000000000000000000000000000000000000000000
                              )
                              mstore(
                                  0x20,
                                  0x0000002000000000000000000000000000000000000000000000000000000000
                              )
                              mstore(0x40, m)
                              revert(0, len)
                          }
                          let rate := mload(add(commissionInfo, 0x40))
                          if gt(rate, commissionRateLimit) {
                              _revertWithReason(
                                  0x0000001b6572726f7220636f6d6d697373696f6e2072617465206c696d697400,
                                  0x5f
                              ) //"error commission rate limit"
                          }
                          let token := mload(add(commissionInfo, 0x80))
                          let referer := mload(add(commissionInfo, 0x60))
                          switch eq(token, _ETH)
                          case 1 {
                              if lt(selfbalance(), balanceBefore) {
                                  _revertWithReason(
                                      0x0000000a737562206661696c65640000000000000000000000000000000000000,
                                      0x4d
                                  ) // sub failed
                              }
                              let inputAmount := sub(selfbalance(), balanceBefore)
                              amount := div(mul(inputAmount, rate), 10000)
                              let success := call(gas(), referer, amount, 0, 0, 0, 0)
                              if eq(success, 0) {
                                  _revertWithReason(
                                      0x000000197472616e73666572206574682072656665726572206661696c000000,
                                      0x5d
                                  ) // transfer eth referer fail
                              }
                              success := call(
                                  gas(),
                                  receiver,
                                  sub(inputAmount, amount),
                                  0,
                                  0,
                                  0,
                                  0
                              )
                              if eq(success, 0) {
                                  _revertWithReason(
                                      0x0000001a7472616e7366657220657468207265636569766572206661696c0000,
                                      0x5e
                                  ) // transfer eth receiver fail
                              }
                          }
                          default {
                              let freePtr := mload(0x40)
                              mstore(0x40, add(freePtr, 0x48))
                              mstore(
                                  freePtr,
                                  0xa9059cbba9059cbb70a082310000000000000000000000000000000000000000
                              ) // transfer transfer balanceOf
                              mstore(add(freePtr, 0x0c), address())
                              let success := staticcall(
                                  gas(),
                                  token,
                                  add(freePtr, 8),
                                  36,
                                  0,
                                  0x20
                              )
                              if eq(success, 0) {
                                  _revertWithReason(
                                      0x000000146765742062616c616e63654f66206661696c65640000000000000000,
                                      0x58
                                  )
                              }
                              let balanceAfter := mload(0x00)
                              if lt(balanceAfter, balanceBefore) {
                                  _revertWithReason(
                                      0x0000000a737562206661696c65640000000000000000000000000000000000000,
                                      0x4d
                                  ) // sub failed
                              }
                              let inputAmount := sub(balanceAfter, balanceBefore)
                              amount := div(mul(inputAmount, rate), 10000)
                              mstore(add(freePtr, 0x08), referer)
                              mstore(add(freePtr, 0x28), amount)
                              success := call(gas(), token, 0, add(freePtr, 4), 0x44, 0, 0)
                              if eq(success, 0) {
                                  _revertWithReason(
                                      0x0000001b7472616e7366657220746f6b656e2072656665726572206661696c00,
                                      0x5f
                                  ) //transfer token referer fail
                              }
                              mstore(add(freePtr, 0x04), receiver)
                              mstore(add(freePtr, 0x24), sub(inputAmount, amount))
                              success := call(gas(), token, 0, freePtr, 0x44, 0, 0)
                              if eq(success, 0) {
                                  _revertWithReason(
                                      0x0000001c7472616e7366657220746f6b656e207265636569766572206661696c,
                                      0x60
                                  ) //transfer token receiver fail
                              }
                          }
                          let freePtr := mload(0x40)
                          mstore(0x40, add(freePtr, 0x40))
                          mstore(freePtr, amount)
                          mstore(add(freePtr, 0x20), referer)
                          log1(
                              freePtr,
                              0x40,
                              0xffc60ee157a42f4d8edbd1897e6581a96d9ed04e44fb2ab53a47ce1eb8f2775b
                          ) //emit CommissionRecord(commissionAmount, refererAddress);
                      }
                  }
              }
              /// SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              /// @title Base contract with common permit handling logics
              abstract contract CommonUtils {
                address internal constant _ETH = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
                uint256 internal constant _ADDRESS_MASK = 0x000000000000000000000000ffffffffffffffffffffffffffffffffffffffff;
                uint256 internal constant _REVERSE_MASK = 0x8000000000000000000000000000000000000000000000000000000000000000;
                uint256 internal constant _ORDER_ID_MASK = 0xffffffffffffffffffffffff0000000000000000000000000000000000000000;
                uint256 internal constant _WEIGHT_MASK = 0x00000000000000000000ffff0000000000000000000000000000000000000000;
                uint256 internal constant _CALL_GAS_LIMIT = 5000;
                /// @dev WETH address is network-specific and needs to be changed before deployment.
                /// It can not be moved to immutable as immutables are not supported in assembly
                // ETH:     C02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2
                // BSC:     bb4CdB9CBd36B01bD1cBaEBF2De08d9173bc095c
                // OEC:     8f8526dbfd6e38e3d8307702ca8469bae6c56c15
                // LOCAL:   5FbDB2315678afecb367f032d93F642f64180aa3
                // LOCAL2:  02121128f1Ed0AdA5Df3a87f42752fcE4Ad63e59
                // POLYGON: 0d500B1d8E8eF31E21C99d1Db9A6444d3ADf1270
                // AVAX:    B31f66AA3C1e785363F0875A1B74E27b85FD66c7
                // FTM:     21be370D5312f44cB42ce377BC9b8a0cEF1A4C83
                // ARB:     82aF49447D8a07e3bd95BD0d56f35241523fBab1
                // OP:      4200000000000000000000000000000000000006
                // CRO:     5C7F8A570d578ED84E63fdFA7b1eE72dEae1AE23
                // CFX:     14b2D3bC65e74DAE1030EAFd8ac30c533c976A9b
                // POLYZK   4F9A0e7FD2Bf6067db6994CF12E4495Df938E6e9
                address public constant _WETH = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
                // address public constant _WETH = 0x5FbDB2315678afecb367f032d93F642f64180aa3;    // hardhat1
                // address public constant _WETH = 0x707531c9999AaeF9232C8FEfBA31FBa4cB78d84a;    // hardhat2
                // ETH:     70cBb871E8f30Fc8Ce23609E9E0Ea87B6b222F58
                // ETH-DEV:02D0131E5Cc86766e234EbF1eBe33444443b98a3
                // BSC:     d99cAE3FAC551f6b6Ba7B9f19bDD316951eeEE98
                // OEC:     E9BBD6eC0c9Ca71d3DcCD1282EE9de4F811E50aF
                // LOCAL:   e7f1725E7734CE288F8367e1Bb143E90bb3F0512
                // LOCAL2:  95D7fF1684a8F2e202097F28Dc2e56F773A55D02
                // POLYGON: 40aA958dd87FC8305b97f2BA922CDdCa374bcD7f
                // AVAX:    70cBb871E8f30Fc8Ce23609E9E0Ea87B6b222F58
                // FTM:     E9BBD6eC0c9Ca71d3DcCD1282EE9de4F811E50aF
                // ARB:     E9BBD6eC0c9Ca71d3DcCD1282EE9de4F811E50aF
                // OP:      100F3f74125C8c724C7C0eE81E4dd5626830dD9a
                // CRO:     E9BBD6eC0c9Ca71d3DcCD1282EE9de4F811E50aF
                // CFX:     100F3f74125C8c724C7C0eE81E4dd5626830dD9a
                // POLYZK   1b5d39419C268b76Db06DE49e38B010fbFB5e226
                address public constant _APPROVE_PROXY = 0x70cBb871E8f30Fc8Ce23609E9E0Ea87B6b222F58;
                // address public constant _APPROVE_PROXY = 0xe7f1725E7734CE288F8367e1Bb143E90bb3F0512;    // hardhat1
                // address public constant _APPROVE_PROXY = 0x2538a10b7fFb1B78c890c870FC152b10be121f04;    // hardhat2
                // ETH:     5703B683c7F928b721CA95Da988d73a3299d4757
                // BSC:     0B5f474ad0e3f7ef629BD10dbf9e4a8Fd60d9A48
                // OEC:     d99cAE3FAC551f6b6Ba7B9f19bDD316951eeEE98
                // LOCAL:   D49a0e9A4CD5979aE36840f542D2d7f02C4817Be
                // LOCAL2:  11457D5b1025D162F3d9B7dBeab6E1fBca20e043
                // POLYGON: f332761c673b59B21fF6dfa8adA44d78c12dEF09
                // AVAX:    3B86917369B83a6892f553609F3c2F439C184e31
                // FTM:     40aA958dd87FC8305b97f2BA922CDdCa374bcD7f
                // ARB:     d99cAE3FAC551f6b6Ba7B9f19bDD316951eeEE98
                // OP:      40aA958dd87FC8305b97f2BA922CDdCa374bcD7f
                // CRO:     40aA958dd87FC8305b97f2BA922CDdCa374bcD7f
                // CFX:     40aA958dd87FC8305b97f2BA922CDdCa374bcD7f
                // POLYZK   d2F0aC2012C8433F235c8e5e97F2368197DD06C7
                address public constant _WNATIVE_RELAY = 0x5703B683c7F928b721CA95Da988d73a3299d4757;
                // address public constant _WNATIVE_RELAY = 0x0B306BF915C4d645ff596e518fAf3F9669b97016;   // hardhat1
                // address public constant _WNATIVE_RELAY = 0x6A47346e722937B60Df7a1149168c0E76DD6520f;   // hardhat2
                event OrderRecord(address fromToken, address toToken, address sender, uint256 fromAmount, uint256 returnAmount);
                event SwapOrderId(uint256 id);
              }
              /// SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              /// @title Base contract with common payable logics
              abstract contract EthReceiver {
                receive() external payable {
                  // solhint-disable-next-line avoid-tx-origin
                  require(msg.sender != tx.origin, "ETH deposit rejected");
                }
              }
              /// SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              import "../interfaces/IERC20Permit.sol";
              import "../interfaces/IDaiLikePermit.sol";
              import "./RevertReasonParser.sol";
              /// @title Base contract with common permit handling logics
              abstract contract Permitable {
                function _permit(address token, bytes calldata permit) internal {
                  if (permit.length > 0) {
                    bool success;
                    bytes memory result;
                    if (permit.length == 32 * 7) {
                      // solhint-disable-next-line avoid-low-level-calls
                      (success, result) = token.call(abi.encodePacked(IERC20Permit.permit.selector, permit));
                    } else if (permit.length == 32 * 8) {
                      // solhint-disable-next-line avoid-low-level-calls
                      (success, result) = token.call(abi.encodePacked(IDaiLikePermit.permit.selector, permit));
                    } else {
                      revert("Wrong permit length");
                    }
                    if (!success) {
                      revert(RevertReasonParser.parse(result, "Permit failed: "));
                    }
                  }
                }
              }
              /// SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              library PMMLib {
                // ============ Struct ============
                struct PMMSwapRequest {
                    uint256 pathIndex;
                    address payer;
                    address fromToken;
                    address toToken;
                    uint256 fromTokenAmountMax;
                    uint256 toTokenAmountMax;
                    uint256 salt;
                    uint256 deadLine;
                    bool isPushOrder;
                    bytes extension;
                    // address marketMaker;
                    // uint256 subIndex;
                    // bytes signature;
                    // uint256 source;  1byte type + 1byte bool(reverse) + 0...0 + 20 bytes address
                }
                struct PMMBaseRequest {
                  uint256 fromTokenAmount;
                  uint256 minReturnAmount;
                  uint256 deadLine;
                  bool fromNative;
                  bool toNative;
                }
                enum PMM_ERROR {
                    NO_ERROR,
                    INVALID_OPERATOR,
                    QUOTE_EXPIRED,
                    ORDER_CANCELLED_OR_FINALIZED,
                    REMAINING_AMOUNT_NOT_ENOUGH,
                    INVALID_AMOUNT_REQUEST,
                    FROM_TOKEN_PAYER_ERROR,
                    TO_TOKEN_PAYER_ERROR,
                    WRONG_FROM_TOKEN
                }
                event PMMSwap(
                  uint256 pathIndex,
                  uint256 subIndex,
                  uint256 errorCode
                );
                error PMMErrorCode(uint256 errorCode);
              }/// SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              library RevertReasonForwarder {
                  function reRevert() internal pure {
                      // bubble up revert reason from latest external call
                      /// @solidity memory-safe-assembly
                      assembly { // solhint-disable-line no-inline-assembly
                          let ptr := mload(0x40)
                          returndatacopy(ptr, 0, returndatasize())
                          revert(ptr, returndatasize())
                      }
                  }
              }// SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              /// @title Library that allows to parse unsuccessful arbitrary calls revert reasons.
              /// See https://solidity.readthedocs.io/en/latest/control-structures.html#revert for details.
              /// Note that we assume revert reason being abi-encoded as Error(string) so it may fail to parse reason
              /// if structured reverts appear in the future.
              ///
              /// All unsuccessful parsings get encoded as Unknown(data) string
              library RevertReasonParser {
                  bytes4 private constant _PANIC_SELECTOR =
                      bytes4(keccak256("Panic(uint256)"));
                  bytes4 private constant _ERROR_SELECTOR =
                      bytes4(keccak256("Error(string)"));
                  function parse(bytes memory data, string memory prefix)
                      internal
                      pure
                      returns (string memory)
                  {
                      if (data.length >= 4) {
                          bytes4 selector;
                          assembly {
                              // solhint-disable-line no-inline-assembly
                              selector := mload(add(data, 0x20))
                          }
                          // 68 = 4-byte selector + 32 bytes offset + 32 bytes length
                          if (selector == _ERROR_SELECTOR && data.length >= 68) {
                              uint256 offset;
                              bytes memory reason;
                              // solhint-disable no-inline-assembly
                              assembly {
                                  // 36 = 32 bytes data length + 4-byte selector
                                  offset := mload(add(data, 36))
                                  reason := add(data, add(36, offset))
                              }
                              /*
                                  revert reason is padded up to 32 bytes with ABI encoder: Error(string)
                                  also sometimes there is extra 32 bytes of zeros padded in the end:
                                  https://github.com/ethereum/solidity/issues/10170
                                  because of that we can't check for equality and instead check
                                  that offset + string length + extra 36 bytes is less than overall data length
                              */
                              require(
                                  data.length >= 36 + offset + reason.length,
                                  "Invalid revert reason"
                              );
                              return string(abi.encodePacked(prefix, "Error(", reason, ")"));
                          }
                          // 36 = 4-byte selector + 32 bytes integer
                          else if (selector == _PANIC_SELECTOR && data.length == 36) {
                              uint256 code;
                              // solhint-disable no-inline-assembly
                              assembly {
                                  // 36 = 32 bytes data length + 4-byte selector
                                  code := mload(add(data, 36))
                              }
                              return
                                  string(
                                      abi.encodePacked(prefix, "Panic(", _toHex(code), ")")
                                  );
                          }
                      }
                      return string(abi.encodePacked(prefix, "Unknown(", _toHex(data), ")"));
                  }
                  function _toHex(uint256 value) private pure returns (string memory) {
                      return _toHex(abi.encodePacked(value));
                  }
                  function _toHex(bytes memory data) private pure returns (string memory) {
                      bytes16 alphabet = 0x30313233343536373839616263646566;
                      bytes memory str = new bytes(2 + data.length * 2);
                      str[0] = "0";
                      str[1] = "x";
                      for (uint256 i = 0; i < data.length; i++) {
                          str[2 * i + 2] = alphabet[uint8(data[i] >> 4)];
                          str[2 * i + 3] = alphabet[uint8(data[i] & 0x0f)];
                      }
                      return string(str);
                  }
              }
              /// SPDX-License-Identifier: MIT
              pragma solidity 0.8.17;
              library RouterErrors {
                  error ReturnAmountIsNotEnough();
                  error InvalidMsgValue();
                  error ERC20TransferFailed();
                  error EmptyPools();
                  error InvalidFromToken();
                  error MsgValuedNotRequired();
              }/// SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              /**
               * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
               * checks.
               *
               * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
               * easily result in undesired exploitation or bugs, since developers usually
               * assume that overflows raise errors. `SafeCast` restores this intuition by
               * reverting the transaction when such an operation overflows.
               *
               * Using this library instead of the unchecked operations eliminates an entire
               * class of bugs, so it's recommended to use it always.
               *
               * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
               * all math on `uint256` and `int256` and then downcasting.
               */
              library SafeCast {
                  /**
                   * @dev Returns the downcasted uint248 from uint256, reverting on
                   * overflow (when the input is greater than largest uint248).
                   *
                   * Counterpart to Solidity's `uint248` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 248 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint248(uint256 value) internal pure returns (uint248) {
                      require(value <= type(uint248).max, "SafeCast: value doesn't fit in 248 bits");
                      return uint248(value);
                  }
                  /**
                   * @dev Returns the downcasted uint240 from uint256, reverting on
                   * overflow (when the input is greater than largest uint240).
                   *
                   * Counterpart to Solidity's `uint240` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 240 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint240(uint256 value) internal pure returns (uint240) {
                      require(value <= type(uint240).max, "SafeCast: value doesn't fit in 240 bits");
                      return uint240(value);
                  }
                  /**
                   * @dev Returns the downcasted uint232 from uint256, reverting on
                   * overflow (when the input is greater than largest uint232).
                   *
                   * Counterpart to Solidity's `uint232` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 232 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint232(uint256 value) internal pure returns (uint232) {
                      require(value <= type(uint232).max, "SafeCast: value doesn't fit in 232 bits");
                      return uint232(value);
                  }
                  /**
                   * @dev Returns the downcasted uint224 from uint256, reverting on
                   * overflow (when the input is greater than largest uint224).
                   *
                   * Counterpart to Solidity's `uint224` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 224 bits
                   *
                   * _Available since v4.2._
                   */
                  function toUint224(uint256 value) internal pure returns (uint224) {
                      require(value <= type(uint224).max, "SafeCast: value doesn't fit in 224 bits");
                      return uint224(value);
                  }
                  /**
                   * @dev Returns the downcasted uint216 from uint256, reverting on
                   * overflow (when the input is greater than largest uint216).
                   *
                   * Counterpart to Solidity's `uint216` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 216 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint216(uint256 value) internal pure returns (uint216) {
                      require(value <= type(uint216).max, "SafeCast: value doesn't fit in 216 bits");
                      return uint216(value);
                  }
                  /**
                   * @dev Returns the downcasted uint208 from uint256, reverting on
                   * overflow (when the input is greater than largest uint208).
                   *
                   * Counterpart to Solidity's `uint208` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 208 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint208(uint256 value) internal pure returns (uint208) {
                      require(value <= type(uint208).max, "SafeCast: value doesn't fit in 208 bits");
                      return uint208(value);
                  }
                  /**
                   * @dev Returns the downcasted uint200 from uint256, reverting on
                   * overflow (when the input is greater than largest uint200).
                   *
                   * Counterpart to Solidity's `uint200` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 200 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint200(uint256 value) internal pure returns (uint200) {
                      require(value <= type(uint200).max, "SafeCast: value doesn't fit in 200 bits");
                      return uint200(value);
                  }
                  /**
                   * @dev Returns the downcasted uint192 from uint256, reverting on
                   * overflow (when the input is greater than largest uint192).
                   *
                   * Counterpart to Solidity's `uint192` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 192 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint192(uint256 value) internal pure returns (uint192) {
                      require(value <= type(uint192).max, "SafeCast: value doesn't fit in 192 bits");
                      return uint192(value);
                  }
                  /**
                   * @dev Returns the downcasted uint184 from uint256, reverting on
                   * overflow (when the input is greater than largest uint184).
                   *
                   * Counterpart to Solidity's `uint184` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 184 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint184(uint256 value) internal pure returns (uint184) {
                      require(value <= type(uint184).max, "SafeCast: value doesn't fit in 184 bits");
                      return uint184(value);
                  }
                  /**
                   * @dev Returns the downcasted uint176 from uint256, reverting on
                   * overflow (when the input is greater than largest uint176).
                   *
                   * Counterpart to Solidity's `uint176` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 176 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint176(uint256 value) internal pure returns (uint176) {
                      require(value <= type(uint176).max, "SafeCast: value doesn't fit in 176 bits");
                      return uint176(value);
                  }
                  /**
                   * @dev Returns the downcasted uint168 from uint256, reverting on
                   * overflow (when the input is greater than largest uint168).
                   *
                   * Counterpart to Solidity's `uint168` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 168 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint168(uint256 value) internal pure returns (uint168) {
                      require(value <= type(uint168).max, "SafeCast: value doesn't fit in 168 bits");
                      return uint168(value);
                  }
                  /**
                   * @dev Returns the downcasted uint160 from uint256, reverting on
                   * overflow (when the input is greater than largest uint160).
                   *
                   * Counterpart to Solidity's `uint160` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 160 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint160(uint256 value) internal pure returns (uint160) {
                      require(value <= type(uint160).max, "SafeCast: value doesn't fit in 160 bits");
                      return uint160(value);
                  }
                  /**
                   * @dev Returns the downcasted uint152 from uint256, reverting on
                   * overflow (when the input is greater than largest uint152).
                   *
                   * Counterpart to Solidity's `uint152` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 152 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint152(uint256 value) internal pure returns (uint152) {
                      require(value <= type(uint152).max, "SafeCast: value doesn't fit in 152 bits");
                      return uint152(value);
                  }
                  /**
                   * @dev Returns the downcasted uint144 from uint256, reverting on
                   * overflow (when the input is greater than largest uint144).
                   *
                   * Counterpart to Solidity's `uint144` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 144 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint144(uint256 value) internal pure returns (uint144) {
                      require(value <= type(uint144).max, "SafeCast: value doesn't fit in 144 bits");
                      return uint144(value);
                  }
                  /**
                   * @dev Returns the downcasted uint136 from uint256, reverting on
                   * overflow (when the input is greater than largest uint136).
                   *
                   * Counterpart to Solidity's `uint136` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 136 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint136(uint256 value) internal pure returns (uint136) {
                      require(value <= type(uint136).max, "SafeCast: value doesn't fit in 136 bits");
                      return uint136(value);
                  }
                  /**
                   * @dev Returns the downcasted uint128 from uint256, reverting on
                   * overflow (when the input is greater than largest uint128).
                   *
                   * Counterpart to Solidity's `uint128` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 128 bits
                   *
                   * _Available since v2.5._
                   */
                  function toUint128(uint256 value) internal pure returns (uint128) {
                      require(value <= type(uint128).max, "SafeCast: value doesn't fit in 128 bits");
                      return uint128(value);
                  }
                  /**
                   * @dev Returns the downcasted uint120 from uint256, reverting on
                   * overflow (when the input is greater than largest uint120).
                   *
                   * Counterpart to Solidity's `uint120` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 120 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint120(uint256 value) internal pure returns (uint120) {
                      require(value <= type(uint120).max, "SafeCast: value doesn't fit in 120 bits");
                      return uint120(value);
                  }
                  /**
                   * @dev Returns the downcasted uint112 from uint256, reverting on
                   * overflow (when the input is greater than largest uint112).
                   *
                   * Counterpart to Solidity's `uint112` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 112 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint112(uint256 value) internal pure returns (uint112) {
                      require(value <= type(uint112).max, "SafeCast: value doesn't fit in 112 bits");
                      return uint112(value);
                  }
                  /**
                   * @dev Returns the downcasted uint104 from uint256, reverting on
                   * overflow (when the input is greater than largest uint104).
                   *
                   * Counterpart to Solidity's `uint104` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 104 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint104(uint256 value) internal pure returns (uint104) {
                      require(value <= type(uint104).max, "SafeCast: value doesn't fit in 104 bits");
                      return uint104(value);
                  }
                  /**
                   * @dev Returns the downcasted uint96 from uint256, reverting on
                   * overflow (when the input is greater than largest uint96).
                   *
                   * Counterpart to Solidity's `uint96` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 96 bits
                   *
                   * _Available since v4.2._
                   */
                  function toUint96(uint256 value) internal pure returns (uint96) {
                      require(value <= type(uint96).max, "SafeCast: value doesn't fit in 96 bits");
                      return uint96(value);
                  }
                  /**
                   * @dev Returns the downcasted uint88 from uint256, reverting on
                   * overflow (when the input is greater than largest uint88).
                   *
                   * Counterpart to Solidity's `uint88` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 88 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint88(uint256 value) internal pure returns (uint88) {
                      require(value <= type(uint88).max, "SafeCast: value doesn't fit in 88 bits");
                      return uint88(value);
                  }
                  /**
                   * @dev Returns the downcasted uint80 from uint256, reverting on
                   * overflow (when the input is greater than largest uint80).
                   *
                   * Counterpart to Solidity's `uint80` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 80 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint80(uint256 value) internal pure returns (uint80) {
                      require(value <= type(uint80).max, "SafeCast: value doesn't fit in 80 bits");
                      return uint80(value);
                  }
                  /**
                   * @dev Returns the downcasted uint72 from uint256, reverting on
                   * overflow (when the input is greater than largest uint72).
                   *
                   * Counterpart to Solidity's `uint72` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 72 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint72(uint256 value) internal pure returns (uint72) {
                      require(value <= type(uint72).max, "SafeCast: value doesn't fit in 72 bits");
                      return uint72(value);
                  }
                  /**
                   * @dev Returns the downcasted uint64 from uint256, reverting on
                   * overflow (when the input is greater than largest uint64).
                   *
                   * Counterpart to Solidity's `uint64` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 64 bits
                   *
                   * _Available since v2.5._
                   */
                  function toUint64(uint256 value) internal pure returns (uint64) {
                      require(value <= type(uint64).max, "SafeCast: value doesn't fit in 64 bits");
                      return uint64(value);
                  }
                  /**
                   * @dev Returns the downcasted uint56 from uint256, reverting on
                   * overflow (when the input is greater than largest uint56).
                   *
                   * Counterpart to Solidity's `uint56` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 56 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint56(uint256 value) internal pure returns (uint56) {
                      require(value <= type(uint56).max, "SafeCast: value doesn't fit in 56 bits");
                      return uint56(value);
                  }
                  /**
                   * @dev Returns the downcasted uint48 from uint256, reverting on
                   * overflow (when the input is greater than largest uint48).
                   *
                   * Counterpart to Solidity's `uint48` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 48 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint48(uint256 value) internal pure returns (uint48) {
                      require(value <= type(uint48).max, "SafeCast: value doesn't fit in 48 bits");
                      return uint48(value);
                  }
                  /**
                   * @dev Returns the downcasted uint40 from uint256, reverting on
                   * overflow (when the input is greater than largest uint40).
                   *
                   * Counterpart to Solidity's `uint40` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 40 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint40(uint256 value) internal pure returns (uint40) {
                      require(value <= type(uint40).max, "SafeCast: value doesn't fit in 40 bits");
                      return uint40(value);
                  }
                  /**
                   * @dev Returns the downcasted uint32 from uint256, reverting on
                   * overflow (when the input is greater than largest uint32).
                   *
                   * Counterpart to Solidity's `uint32` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 32 bits
                   *
                   * _Available since v2.5._
                   */
                  function toUint32(uint256 value) internal pure returns (uint32) {
                      require(value <= type(uint32).max, "SafeCast: value doesn't fit in 32 bits");
                      return uint32(value);
                  }
                  /**
                   * @dev Returns the downcasted uint24 from uint256, reverting on
                   * overflow (when the input is greater than largest uint24).
                   *
                   * Counterpart to Solidity's `uint24` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 24 bits
                   *
                   * _Available since v4.7._
                   */
                  function toUint24(uint256 value) internal pure returns (uint24) {
                      require(value <= type(uint24).max, "SafeCast: value doesn't fit in 24 bits");
                      return uint24(value);
                  }
                  /**
                   * @dev Returns the downcasted uint16 from uint256, reverting on
                   * overflow (when the input is greater than largest uint16).
                   *
                   * Counterpart to Solidity's `uint16` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 16 bits
                   *
                   * _Available since v2.5._
                   */
                  function toUint16(uint256 value) internal pure returns (uint16) {
                      require(value <= type(uint16).max, "SafeCast: value doesn't fit in 16 bits");
                      return uint16(value);
                  }
                  /**
                   * @dev Returns the downcasted uint8 from uint256, reverting on
                   * overflow (when the input is greater than largest uint8).
                   *
                   * Counterpart to Solidity's `uint8` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 8 bits
                   *
                   * _Available since v2.5._
                   */
                  function toUint8(uint256 value) internal pure returns (uint8) {
                      require(value <= type(uint8).max, "SafeCast: value doesn't fit in 8 bits");
                      return uint8(value);
                  }
                  /**
                   * @dev Converts a signed int256 into an unsigned uint256.
                   *
                   * Requirements:
                   *
                   * - input must be greater than or equal to 0.
                   *
                   * _Available since v3.0._
                   */
                  function toUint256(int256 value) internal pure returns (uint256) {
                      require(value >= 0, "SafeCast: value must be positive");
                      return uint256(value);
                  }
                  /**
                   * @dev Returns the downcasted int248 from int256, reverting on
                   * overflow (when the input is less than smallest int248 or
                   * greater than largest int248).
                   *
                   * Counterpart to Solidity's `int248` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 248 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt248(int256 value) internal pure returns (int248) {
                      require(value >= type(int248).min && value <= type(int248).max, "SafeCast: value doesn't fit in 248 bits");
                      return int248(value);
                  }
                  /**
                   * @dev Returns the downcasted int240 from int256, reverting on
                   * overflow (when the input is less than smallest int240 or
                   * greater than largest int240).
                   *
                   * Counterpart to Solidity's `int240` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 240 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt240(int256 value) internal pure returns (int240) {
                      require(value >= type(int240).min && value <= type(int240).max, "SafeCast: value doesn't fit in 240 bits");
                      return int240(value);
                  }
                  /**
                   * @dev Returns the downcasted int232 from int256, reverting on
                   * overflow (when the input is less than smallest int232 or
                   * greater than largest int232).
                   *
                   * Counterpart to Solidity's `int232` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 232 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt232(int256 value) internal pure returns (int232) {
                      require(value >= type(int232).min && value <= type(int232).max, "SafeCast: value doesn't fit in 232 bits");
                      return int232(value);
                  }
                  /**
                   * @dev Returns the downcasted int224 from int256, reverting on
                   * overflow (when the input is less than smallest int224 or
                   * greater than largest int224).
                   *
                   * Counterpart to Solidity's `int224` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 224 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt224(int256 value) internal pure returns (int224) {
                      require(value >= type(int224).min && value <= type(int224).max, "SafeCast: value doesn't fit in 224 bits");
                      return int224(value);
                  }
                  /**
                   * @dev Returns the downcasted int216 from int256, reverting on
                   * overflow (when the input is less than smallest int216 or
                   * greater than largest int216).
                   *
                   * Counterpart to Solidity's `int216` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 216 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt216(int256 value) internal pure returns (int216) {
                      require(value >= type(int216).min && value <= type(int216).max, "SafeCast: value doesn't fit in 216 bits");
                      return int216(value);
                  }
                  /**
                   * @dev Returns the downcasted int208 from int256, reverting on
                   * overflow (when the input is less than smallest int208 or
                   * greater than largest int208).
                   *
                   * Counterpart to Solidity's `int208` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 208 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt208(int256 value) internal pure returns (int208) {
                      require(value >= type(int208).min && value <= type(int208).max, "SafeCast: value doesn't fit in 208 bits");
                      return int208(value);
                  }
                  /**
                   * @dev Returns the downcasted int200 from int256, reverting on
                   * overflow (when the input is less than smallest int200 or
                   * greater than largest int200).
                   *
                   * Counterpart to Solidity's `int200` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 200 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt200(int256 value) internal pure returns (int200) {
                      require(value >= type(int200).min && value <= type(int200).max, "SafeCast: value doesn't fit in 200 bits");
                      return int200(value);
                  }
                  /**
                   * @dev Returns the downcasted int192 from int256, reverting on
                   * overflow (when the input is less than smallest int192 or
                   * greater than largest int192).
                   *
                   * Counterpart to Solidity's `int192` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 192 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt192(int256 value) internal pure returns (int192) {
                      require(value >= type(int192).min && value <= type(int192).max, "SafeCast: value doesn't fit in 192 bits");
                      return int192(value);
                  }
                  /**
                   * @dev Returns the downcasted int184 from int256, reverting on
                   * overflow (when the input is less than smallest int184 or
                   * greater than largest int184).
                   *
                   * Counterpart to Solidity's `int184` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 184 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt184(int256 value) internal pure returns (int184) {
                      require(value >= type(int184).min && value <= type(int184).max, "SafeCast: value doesn't fit in 184 bits");
                      return int184(value);
                  }
                  /**
                   * @dev Returns the downcasted int176 from int256, reverting on
                   * overflow (when the input is less than smallest int176 or
                   * greater than largest int176).
                   *
                   * Counterpart to Solidity's `int176` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 176 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt176(int256 value) internal pure returns (int176) {
                      require(value >= type(int176).min && value <= type(int176).max, "SafeCast: value doesn't fit in 176 bits");
                      return int176(value);
                  }
                  /**
                   * @dev Returns the downcasted int168 from int256, reverting on
                   * overflow (when the input is less than smallest int168 or
                   * greater than largest int168).
                   *
                   * Counterpart to Solidity's `int168` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 168 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt168(int256 value) internal pure returns (int168) {
                      require(value >= type(int168).min && value <= type(int168).max, "SafeCast: value doesn't fit in 168 bits");
                      return int168(value);
                  }
                  /**
                   * @dev Returns the downcasted int160 from int256, reverting on
                   * overflow (when the input is less than smallest int160 or
                   * greater than largest int160).
                   *
                   * Counterpart to Solidity's `int160` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 160 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt160(int256 value) internal pure returns (int160) {
                      require(value >= type(int160).min && value <= type(int160).max, "SafeCast: value doesn't fit in 160 bits");
                      return int160(value);
                  }
                  /**
                   * @dev Returns the downcasted int152 from int256, reverting on
                   * overflow (when the input is less than smallest int152 or
                   * greater than largest int152).
                   *
                   * Counterpart to Solidity's `int152` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 152 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt152(int256 value) internal pure returns (int152) {
                      require(value >= type(int152).min && value <= type(int152).max, "SafeCast: value doesn't fit in 152 bits");
                      return int152(value);
                  }
                  /**
                   * @dev Returns the downcasted int144 from int256, reverting on
                   * overflow (when the input is less than smallest int144 or
                   * greater than largest int144).
                   *
                   * Counterpart to Solidity's `int144` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 144 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt144(int256 value) internal pure returns (int144) {
                      require(value >= type(int144).min && value <= type(int144).max, "SafeCast: value doesn't fit in 144 bits");
                      return int144(value);
                  }
                  /**
                   * @dev Returns the downcasted int136 from int256, reverting on
                   * overflow (when the input is less than smallest int136 or
                   * greater than largest int136).
                   *
                   * Counterpart to Solidity's `int136` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 136 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt136(int256 value) internal pure returns (int136) {
                      require(value >= type(int136).min && value <= type(int136).max, "SafeCast: value doesn't fit in 136 bits");
                      return int136(value);
                  }
                  /**
                   * @dev Returns the downcasted int128 from int256, reverting on
                   * overflow (when the input is less than smallest int128 or
                   * greater than largest int128).
                   *
                   * Counterpart to Solidity's `int128` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 128 bits
                   *
                   * _Available since v3.1._
                   */
                  function toInt128(int256 value) internal pure returns (int128) {
                      require(value >= type(int128).min && value <= type(int128).max, "SafeCast: value doesn't fit in 128 bits");
                      return int128(value);
                  }
                  /**
                   * @dev Returns the downcasted int120 from int256, reverting on
                   * overflow (when the input is less than smallest int120 or
                   * greater than largest int120).
                   *
                   * Counterpart to Solidity's `int120` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 120 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt120(int256 value) internal pure returns (int120) {
                      require(value >= type(int120).min && value <= type(int120).max, "SafeCast: value doesn't fit in 120 bits");
                      return int120(value);
                  }
                  /**
                   * @dev Returns the downcasted int112 from int256, reverting on
                   * overflow (when the input is less than smallest int112 or
                   * greater than largest int112).
                   *
                   * Counterpart to Solidity's `int112` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 112 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt112(int256 value) internal pure returns (int112) {
                      require(value >= type(int112).min && value <= type(int112).max, "SafeCast: value doesn't fit in 112 bits");
                      return int112(value);
                  }
                  /**
                   * @dev Returns the downcasted int104 from int256, reverting on
                   * overflow (when the input is less than smallest int104 or
                   * greater than largest int104).
                   *
                   * Counterpart to Solidity's `int104` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 104 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt104(int256 value) internal pure returns (int104) {
                      require(value >= type(int104).min && value <= type(int104).max, "SafeCast: value doesn't fit in 104 bits");
                      return int104(value);
                  }
                  /**
                   * @dev Returns the downcasted int96 from int256, reverting on
                   * overflow (when the input is less than smallest int96 or
                   * greater than largest int96).
                   *
                   * Counterpart to Solidity's `int96` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 96 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt96(int256 value) internal pure returns (int96) {
                      require(value >= type(int96).min && value <= type(int96).max, "SafeCast: value doesn't fit in 96 bits");
                      return int96(value);
                  }
                  /**
                   * @dev Returns the downcasted int88 from int256, reverting on
                   * overflow (when the input is less than smallest int88 or
                   * greater than largest int88).
                   *
                   * Counterpart to Solidity's `int88` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 88 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt88(int256 value) internal pure returns (int88) {
                      require(value >= type(int88).min && value <= type(int88).max, "SafeCast: value doesn't fit in 88 bits");
                      return int88(value);
                  }
                  /**
                   * @dev Returns the downcasted int80 from int256, reverting on
                   * overflow (when the input is less than smallest int80 or
                   * greater than largest int80).
                   *
                   * Counterpart to Solidity's `int80` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 80 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt80(int256 value) internal pure returns (int80) {
                      require(value >= type(int80).min && value <= type(int80).max, "SafeCast: value doesn't fit in 80 bits");
                      return int80(value);
                  }
                  /**
                   * @dev Returns the downcasted int72 from int256, reverting on
                   * overflow (when the input is less than smallest int72 or
                   * greater than largest int72).
                   *
                   * Counterpart to Solidity's `int72` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 72 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt72(int256 value) internal pure returns (int72) {
                      require(value >= type(int72).min && value <= type(int72).max, "SafeCast: value doesn't fit in 72 bits");
                      return int72(value);
                  }
                  /**
                   * @dev Returns the downcasted int64 from int256, reverting on
                   * overflow (when the input is less than smallest int64 or
                   * greater than largest int64).
                   *
                   * Counterpart to Solidity's `int64` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 64 bits
                   *
                   * _Available since v3.1._
                   */
                  function toInt64(int256 value) internal pure returns (int64) {
                      require(value >= type(int64).min && value <= type(int64).max, "SafeCast: value doesn't fit in 64 bits");
                      return int64(value);
                  }
                  /**
                   * @dev Returns the downcasted int56 from int256, reverting on
                   * overflow (when the input is less than smallest int56 or
                   * greater than largest int56).
                   *
                   * Counterpart to Solidity's `int56` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 56 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt56(int256 value) internal pure returns (int56) {
                      require(value >= type(int56).min && value <= type(int56).max, "SafeCast: value doesn't fit in 56 bits");
                      return int56(value);
                  }
                  /**
                   * @dev Returns the downcasted int48 from int256, reverting on
                   * overflow (when the input is less than smallest int48 or
                   * greater than largest int48).
                   *
                   * Counterpart to Solidity's `int48` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 48 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt48(int256 value) internal pure returns (int48) {
                      require(value >= type(int48).min && value <= type(int48).max, "SafeCast: value doesn't fit in 48 bits");
                      return int48(value);
                  }
                  /**
                   * @dev Returns the downcasted int40 from int256, reverting on
                   * overflow (when the input is less than smallest int40 or
                   * greater than largest int40).
                   *
                   * Counterpart to Solidity's `int40` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 40 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt40(int256 value) internal pure returns (int40) {
                      require(value >= type(int40).min && value <= type(int40).max, "SafeCast: value doesn't fit in 40 bits");
                      return int40(value);
                  }
                  /**
                   * @dev Returns the downcasted int32 from int256, reverting on
                   * overflow (when the input is less than smallest int32 or
                   * greater than largest int32).
                   *
                   * Counterpart to Solidity's `int32` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 32 bits
                   *
                   * _Available since v3.1._
                   */
                  function toInt32(int256 value) internal pure returns (int32) {
                      require(value >= type(int32).min && value <= type(int32).max, "SafeCast: value doesn't fit in 32 bits");
                      return int32(value);
                  }
                  /**
                   * @dev Returns the downcasted int24 from int256, reverting on
                   * overflow (when the input is less than smallest int24 or
                   * greater than largest int24).
                   *
                   * Counterpart to Solidity's `int24` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 24 bits
                   *
                   * _Available since v4.7._
                   */
                  function toInt24(int256 value) internal pure returns (int24) {
                      require(value >= type(int24).min && value <= type(int24).max, "SafeCast: value doesn't fit in 24 bits");
                      return int24(value);
                  }
                  /**
                   * @dev Returns the downcasted int16 from int256, reverting on
                   * overflow (when the input is less than smallest int16 or
                   * greater than largest int16).
                   *
                   * Counterpart to Solidity's `int16` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 16 bits
                   *
                   * _Available since v3.1._
                   */
                  function toInt16(int256 value) internal pure returns (int16) {
                      require(value >= type(int16).min && value <= type(int16).max, "SafeCast: value doesn't fit in 16 bits");
                      return int16(value);
                  }
                  /**
                   * @dev Returns the downcasted int8 from int256, reverting on
                   * overflow (when the input is less than smallest int8 or
                   * greater than largest int8).
                   *
                   * Counterpart to Solidity's `int8` operator.
                   *
                   * Requirements:
                   *
                   * - input must fit into 8 bits
                   *
                   * _Available since v3.1._
                   */
                  function toInt8(int256 value) internal pure returns (int8) {
                      require(value >= type(int8).min && value <= type(int8).max, "SafeCast: value doesn't fit in 8 bits");
                      return int8(value);
                  }
                  /**
                   * @dev Converts an unsigned uint256 into a signed int256.
                   *
                   * Requirements:
                   *
                   * - input must be less than or equal to maxInt256.
                   *
                   * _Available since v3.0._
                   */
                  function toInt256(uint256 value) internal pure returns (int256) {
                      // Note: Unsafe cast below is okay because `type(int256).max` is guaranteed to be positive
                      require(value <= uint256(type(int256).max), "SafeCast: value doesn't fit in an int256");
                      return int256(value);
                  }
              }
              /// SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              import "./SafeMath.sol";
              import "./Address.sol";
              import "./RevertReasonForwarder.sol";
              import "../interfaces/IERC20.sol";
              import "../interfaces/IERC20Permit.sol";
              import "../interfaces/IDaiLikePermit.sol";
              // File @1inch/solidity-utils/contracts/libraries/[email protected]
              library SafeERC20 {
                  error SafeTransferFailed();
                  error SafeTransferFromFailed();
                  error ForceApproveFailed();
                  error SafeIncreaseAllowanceFailed();
                  error SafeDecreaseAllowanceFailed();
                  error SafePermitBadLength();
                  // Ensures method do not revert or return boolean `true`, admits call to non-smart-contract
                  function safeTransferFrom(IERC20 token, address from, address to, uint256 amount) internal {
                      bytes4 selector = token.transferFrom.selector;
                      bool success;
                      /// @solidity memory-safe-assembly
                      assembly { // solhint-disable-line no-inline-assembly
                          let data := mload(0x40)
                          mstore(data, selector)
                          mstore(add(data, 0x04), from)
                          mstore(add(data, 0x24), to)
                          mstore(add(data, 0x44), amount)
                          success := call(gas(), token, 0, data, 100, 0x0, 0x20)
                          if success {
                              switch returndatasize()
                              case 0 { success := gt(extcodesize(token), 0) }
                              default { success := and(gt(returndatasize(), 31), eq(mload(0), 1)) }
                          }
                      }
                      if (!success) revert SafeTransferFromFailed();
                  }
                  // Ensures method do not revert or return boolean `true`, admits call to non-smart-contract
                  function safeTransfer(IERC20 token, address to, uint256 value) internal {
                      if (!_makeCall(token, token.transfer.selector, to, value)) {
                          revert SafeTransferFailed();
                      }
                  }
                  function safeApprove(IERC20 token, address spender, uint256 value) internal {
                      forceApprove(token, spender, value);
                  }
                  // If `approve(from, to, amount)` fails, try to `approve(from, to, 0)` before retry
                  function forceApprove(IERC20 token, address spender, uint256 value) internal {
                      if (!_makeCall(token, token.approve.selector, spender, value)) {
                          if (!_makeCall(token, token.approve.selector, spender, 0) ||
                              !_makeCall(token, token.approve.selector, spender, value))
                          {
                              revert ForceApproveFailed();
                          }
                      }
                  }
                  
                  function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                      uint256 allowance = token.allowance(address(this), spender);
                      if (value > type(uint256).max - allowance) revert SafeIncreaseAllowanceFailed();
                      forceApprove(token, spender, allowance + value);
                  }
                  function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                      uint256 allowance = token.allowance(address(this), spender);
                      if (value > allowance) revert SafeDecreaseAllowanceFailed();
                      forceApprove(token, spender, allowance - value);
                  }
                  function safePermit(IERC20 token, bytes calldata permit) internal {
                      bool success;
                      if (permit.length == 32 * 7) {
                          success = _makeCalldataCall(token, IERC20Permit.permit.selector, permit);
                      } else if (permit.length == 32 * 8) {
                          success = _makeCalldataCall(token, IDaiLikePermit.permit.selector, permit);
                      } else {
                          revert SafePermitBadLength();
                      }
                      if (!success) RevertReasonForwarder.reRevert();
                  }
                  function _makeCall(IERC20 token, bytes4 selector, address to, uint256 amount) private returns(bool success) {
                      /// @solidity memory-safe-assembly
                      assembly { // solhint-disable-line no-inline-assembly
                          let data := mload(0x40)
                          mstore(data, selector)
                          mstore(add(data, 0x04), to)
                          mstore(add(data, 0x24), amount)
                          success := call(gas(), token, 0, data, 0x44, 0x0, 0x20)
                          if success {
                              switch returndatasize()
                              case 0 { success := gt(extcodesize(token), 0) }
                              default { success := and(gt(returndatasize(), 31), eq(mload(0), 1)) }
                          }
                      }
                  }
                  function _makeCalldataCall(IERC20 token, bytes4 selector, bytes calldata args) private returns(bool success) {
                      /// @solidity memory-safe-assembly
                      assembly { // solhint-disable-line no-inline-assembly
                          let len := add(4, args.length)
                          let data := mload(0x40)
                          mstore(data, selector)
                          calldatacopy(add(data, 0x04), args.offset, args.length)
                          success := call(gas(), token, 0, data, len, 0x0, 0x20)
                          if success {
                              switch returndatasize()
                              case 0 { success := gt(extcodesize(token), 0) }
                              default { success := and(gt(returndatasize(), 31), eq(mload(0), 1)) }
                          }
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              library SafeMath {
                  uint256 constant WAD = 10**18;
                  uint256 constant RAY = 10**27;
                  function wad() public pure returns (uint256) {
                      return WAD;
                  }
                  function ray() public pure returns (uint256) {
                      return RAY;
                  }
                  function add(uint256 a, uint256 b) internal pure returns (uint256) {
                      uint256 c = a + b;
                      require(c >= a, "SafeMath: addition overflow");
                      return c;
                  }
                  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                      return sub(a, b, "SafeMath: subtraction overflow");
                  }
                  function sub(
                      uint256 a,
                      uint256 b,
                      string memory errorMessage
                  ) internal pure returns (uint256) {
                      require(b <= a, errorMessage);
                      uint256 c = a - b;
                      return c;
                  }
                  function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                      // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                      // benefit is lost if 'b' is also tested.
                      // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                      if (a == 0) {
                          return 0;
                      }
                      uint256 c = a * b;
                      require(c / a == b, "SafeMath: multiplication overflow");
                      return c;
                  }
                  function div(uint256 a, uint256 b) internal pure returns (uint256) {
                      return div(a, b, "SafeMath: division by zero");
                  }
                  function div(
                      uint256 a,
                      uint256 b,
                      string memory errorMessage
                  ) internal pure returns (uint256) {
                      // Solidity only automatically asserts when dividing by 0
                      require(b > 0, errorMessage);
                      uint256 c = a / b;
                      // assert(a == b * c + a % b); // There is no case in which this doesn't hold
                      return c;
                  }
                  function mod(uint256 a, uint256 b) internal pure returns (uint256) {
                      return mod(a, b, "SafeMath: modulo by zero");
                  }
                  function mod(
                      uint256 a,
                      uint256 b,
                      string memory errorMessage
                  ) internal pure returns (uint256) {
                      require(b != 0, errorMessage);
                      return a % b;
                  }
                  function min(uint256 a, uint256 b) internal pure returns (uint256) {
                      return a <= b ? a : b;
                  }
                  function max(uint256 a, uint256 b) internal pure returns (uint256) {
                      return a >= b ? a : b;
                  }
                  function sqrt(uint256 a) internal pure returns (uint256 b) {
                      if (a > 3) {
                          b = a;
                          uint256 x = a / 2 + 1;
                          while (x < b) {
                              b = x;
                              x = (a / x + x) / 2;
                          }
                      } else if (a != 0) {
                          b = 1;
                      }
                  }
                  function wmul(uint256 a, uint256 b) internal pure returns (uint256) {
                      return mul(a, b) / WAD;
                  }
                  function wmulRound(uint256 a, uint256 b) internal pure returns (uint256) {
                      return add(mul(a, b), WAD / 2) / WAD;
                  }
                  function rmul(uint256 a, uint256 b) internal pure returns (uint256) {
                      return mul(a, b) / RAY;
                  }
                  function rmulRound(uint256 a, uint256 b) internal pure returns (uint256) {
                      return add(mul(a, b), RAY / 2) / RAY;
                  }
                  function wdiv(uint256 a, uint256 b) internal pure returns (uint256) {
                      return div(mul(a, WAD), b);
                  }
                  function wdivRound(uint256 a, uint256 b) internal pure returns (uint256) {
                      return add(mul(a, WAD), b / 2) / b;
                  }
                  function rdiv(uint256 a, uint256 b) internal pure returns (uint256) {
                      return div(mul(a, RAY), b);
                  }
                  function rdivRound(uint256 a, uint256 b) internal pure returns (uint256) {
                      return add(mul(a, RAY), b / 2) / b;
                  }
                  function wpow(uint256 x, uint256 n) internal pure returns (uint256) {
                      uint256 result = WAD;
                      while (n > 0) {
                          if (n % 2 != 0) {
                              result = wmul(result, x);
                          }
                          x = wmul(x, x);
                          n /= 2;
                      }
                      return result;
                  }
                  function rpow(uint256 x, uint256 n) internal pure returns (uint256) {
                      uint256 result = RAY;
                      while (n > 0) {
                          if (n % 2 != 0) {
                              result = rmul(result, x);
                          }
                          x = rmul(x, x);
                          n /= 2;
                      }
                      return result;
                  }
                  function divCeil(uint256 a, uint256 b) internal pure returns (uint256) {
                      uint256 quotient = div(a, b);
                      uint256 remainder = a - quotient * b;
                      if (remainder > 0) {
                          return quotient + 1;
                      } else {
                          return quotient;
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              import {SafeMath} from "./SafeMath.sol";
              import {IERC20} from "../interfaces/IERC20.sol";
              import {SafeERC20} from "./SafeERC20.sol";
              library UniversalERC20 {
                  using SafeMath for uint256;
                  using SafeERC20 for IERC20;
                  IERC20 private constant ETH_ADDRESS =
                      IERC20(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);
                  function universalTransfer(
                      IERC20 token,
                      address payable to,
                      uint256 amount
                  ) internal {
                      if (amount > 0) {
                          if (isETH(token)) {
                              to.transfer(amount);
                          } else {
                              token.safeTransfer(to, amount);
                          }
                      }
                  }
                  function universalTransferFrom(
                      IERC20 token,
                      address from,
                      address payable to,
                      uint256 amount
                  ) internal {
                      if (amount > 0) {
                          token.safeTransferFrom(from, to, amount);
                      }
                  }
                  function universalApproveMax(
                      IERC20 token,
                      address to,
                      uint256 amount
                  ) internal {
                      uint256 allowance = token.allowance(address(this), to);
                      if (allowance < amount) {
                          token.forceApprove(to, type(uint256).max);
                      }
                  }
                  function universalBalanceOf(IERC20 token, address who)
                      internal
                      view
                      returns (uint256)
                  {
                      if (isETH(token)) {
                          return who.balance;
                      } else {
                          return token.balanceOf(who);
                      }
                  }
                  function tokenBalanceOf(IERC20 token, address who)
                      internal
                      view
                      returns (uint256)
                  {
                      return token.balanceOf(who);
                  }
                  function isETH(IERC20 token) internal pure returns (bool) {
                      return token == ETH_ADDRESS;
                  }
              }
              /// SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              import "../libraries/CommonUtils.sol";
              import "../libraries/SafeERC20.sol";
              import "../interfaces/IWETH.sol";
              import "../interfaces/IWNativeRelayer.sol";
              import "../interfaces/IERC20.sol";
              import "../interfaces/IApproveProxy.sol";
              /// @title Base contract with common payable logics
              abstract contract WrapETHSwap is CommonUtils {
                uint256 private constant SWAP_AMOUNT = 0x00000000000000000000000000000000ffffffffffffffffffffffffffffffff;
                
                function swapWrap(uint256 orderId, uint256 rawdata) external payable {
                  bool reversed;
                  uint128 amount;
                  assembly {
                    reversed := and(rawdata, _REVERSE_MASK)
                    amount := and(rawdata, SWAP_AMOUNT)
                  }
                  require(amount > 0, "amount must be > 0");
                  if (reversed) {
                    IApproveProxy(_APPROVE_PROXY).claimTokens(_WETH, msg.sender, _WNATIVE_RELAY, amount);
                    IWNativeRelayer(_WNATIVE_RELAY).withdraw(amount);
                    (bool success, ) = payable(msg.sender).call{value: address(this).balance}("");
                    require(success, "transfer native token failed");
                  } else {
                    require(msg.value == amount, "value not equal amount");
                    IWETH(_WETH).deposit{value: amount}();
                    SafeERC20.safeTransfer(IERC20(_WETH), msg.sender, amount);
                  }
                  emit SwapOrderId(orderId);
                  emit OrderRecord(reversed ? _WETH : _ETH, reversed ? _ETH: _WETH, msg.sender, amount, amount);
                }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              contract DexRouterStorage {
                  // In the test scenario, we take it as a settable state and adjust it to a constant after it stabilizes
                  address public approveProxy;
                  address public wNativeRelayer;
                  mapping(address => bool) public priorityAddresses;
                  uint256[19] internal _dexRouterGap;
                  address public admin;
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              import "./interfaces/IUni.sol";
              import "./libraries/UniversalERC20.sol";
              import "./libraries/CommonUtils.sol";
              contract UnxswapRouter is CommonUtils {
                  uint256 private constant _IS_TOKEN0_TAX =
                      0x1000000000000000000000000000000000000000000000000000000000000000;
                  uint256 private constant _IS_TOKEN1_TAX =
                      0x2000000000000000000000000000000000000000000000000000000000000000;
                  uint256 private constant _CLAIM_TOKENS_CALL_SELECTOR_32 =
                      0x0a5ea46600000000000000000000000000000000000000000000000000000000;
                  uint256 private constant _TRANSFER_DEPOSIT_SELECTOR =
                      0xa9059cbbd0e30db0000000000000000000000000000000000000000000000000;
                  uint256 private constant _SWAP_GETRESERVES_SELECTOR =
                      0x022c0d9f0902f1ac000000000000000000000000000000000000000000000000;
                  uint256 private constant _WITHDRAW_TRNASFER_SELECTOR =
                      0x2e1a7d4da9059cbb000000000000000000000000000000000000000000000000;
                  uint256 private constant _BALANCEOF_TOKEN0_SELECTOR =
                      0x70a082310dfe1681000000000000000000000000000000000000000000000000;
                  uint256 private constant _BALANCEOF_TOKEN1_SELECTOR =
                      0x70a08231d21220a7000000000000000000000000000000000000000000000000;
                  uint256 private constant _WETH_MASK =
                      0x4000000000000000000000000000000000000000000000000000000000000000;
                  uint256 private constant _NUMERATOR_MASK =
                      0x0000000000000000ffffffff0000000000000000000000000000000000000000;
                  uint256 private constant _DENOMINATOR = 1_000_000_000;
                  uint256 private constant _NUMERATOR_OFFSET = 160;
                  uint256 private constant ETH_ADDRESS = 0x00;
                  //-------------------------------
                  //------- Internal Functions ----
                  //-------------------------------
                  /// @notice Performs the internal logic for executing a swap using the Unxswap protocol.
                  /// @param srcToken The token to be swapped.
                  /// @param amount The amount of the source token to be swapped.
                  /// @param minReturn The minimum amount of tokens that must be received for the swap to be valid, protecting against slippage.
                  /// @param pools The array of pool identifiers that define the swap route.
                  /// @param payer The address of the entity providing the source tokens for the swap.
                  /// @param receiver The address that will receive the tokens after the swap.
                  /// @return returnAmount The amount of tokens received from the swap.
                  /// @dev This internal function encapsulates the core logic of the Unxswap token swap process. It is meant to be called by other external functions that set up the required parameters. The actual interaction with the Unxswap pools and the token transfer mechanics are implemented here.
                  function _unxswapInternal(
                      IERC20 srcToken,
                      uint256 amount,
                      uint256 minReturn,
                      // solhint-disable-next-line no-unused-vars
                      bytes32[] calldata pools,
                      address payer,
                      address receiver
                  ) internal returns (uint256 returnAmount) {
                      assembly {
                          // solhint-disable-line no-inline-assembly
                          function revertWithReason(m, len) {
                              mstore(
                                  0,
                                  0x08c379a000000000000000000000000000000000000000000000000000000000
                              )
                              mstore(
                                  0x20,
                                  0x0000002000000000000000000000000000000000000000000000000000000000
                              )
                              mstore(0x40, m)
                              revert(0, len)
                          }
                          function _getTokenAddr(emptyPtr, pair, selector) -> token {
                              mstore(emptyPtr, selector)
                              if iszero(
                                  staticcall(
                                      gas(),
                                      pair,
                                      add(0x04, emptyPtr),
                                      0x04,
                                      0x00,
                                      0x20
                                  )
                              ) {
                                  revertWithReason(
                                      0x0000001067657420746f6b656e206661696c6564000000000000000000000000,
                                      0x54
                                  ) // "get token failed"
                              }
                              token := mload(0x00)
                          }
                          function _getBalanceOfToken0(emptyPtr, pair) -> token0, balance0 {
                              mstore(emptyPtr, _BALANCEOF_TOKEN0_SELECTOR)
                              if iszero(
                                  staticcall(
                                      gas(),
                                      pair,
                                      add(0x04, emptyPtr),
                                      0x04,
                                      0x00,
                                      0x20
                                  )
                              ) {
                                  revertWithReason(
                                      0x00000012746f6b656e302063616c6c206661696c656400000000000000000000,
                                      0x56
                                  ) // "token0 call failed"
                              }
                              token0 := mload(0x00)
                              mstore(add(0x04, emptyPtr), pair)
                              if iszero(
                                  staticcall(gas(), token0, emptyPtr, 0x24, 0x00, 0x20)
                              ) {
                                  revertWithReason(
                                      0x0000001562616c616e63654f662063616c6c206661696c656400000000000000,
                                      0x59
                                  ) // "balanceOf call failed"
                              }
                              balance0 := mload(0x00)
                          }
                          function _getBalanceOfToken1(emptyPtr, pair) -> token1, balance1 {
                              mstore(emptyPtr, _BALANCEOF_TOKEN1_SELECTOR)
                              if iszero(
                                  staticcall(
                                      gas(),
                                      pair,
                                      add(0x04, emptyPtr),
                                      0x04,
                                      0x00,
                                      0x20
                                  )
                              ) {
                                  revertWithReason(
                                      0x00000012746f6b656e312063616c6c206661696c656400000000000000000000,
                                      0x56
                                  ) // "token1 call failed"
                              }
                              token1 := mload(0x00)
                              mstore(add(0x04, emptyPtr), pair)
                              if iszero(
                                  staticcall(gas(), token1, emptyPtr, 0x24, 0x00, 0x20)
                              ) {
                                  revertWithReason(
                                      0x0000001562616c616e63654f662063616c6c206661696c656400000000000000,
                                      0x59
                                  ) // "balanceOf call failed"
                              }
                              balance1 := mload(0x00)
                          }
                          function swap(
                              emptyPtr,
                              swapAmount,
                              pair,
                              reversed,
                              isToken0Tax,
                              isToken1Tax,
                              numerator,
                              dst
                          ) -> ret {
                              mstore(emptyPtr, _SWAP_GETRESERVES_SELECTOR)
                              if iszero(
                                  staticcall(
                                      gas(),
                                      pair,
                                      add(0x04, emptyPtr),
                                      0x4,
                                      0x00,
                                      0x40
                                  )
                              ) {
                                  // we only need the first 0x40 bytes, no need timestamp info
                                  revertWithReason(
                                      0x0000001472657365727665732063616c6c206661696c65640000000000000000,
                                      0x58
                                  ) // "reserves call failed"
                              }
                              let reserve0 := mload(0x00)
                              let reserve1 := mload(0x20)
                              switch reversed
                              case 0 {
                                  //swap token0 for token1
                                  if isToken0Tax {
                                      let token0, balance0 := _getBalanceOfToken0(
                                          emptyPtr,
                                          pair
                                      )
                                      swapAmount := sub(balance0, reserve0)
                                  }
                              }
                              default {
                                  //swap token1 for token0
                                  if isToken1Tax {
                                      let token1, balance1 := _getBalanceOfToken1(
                                          emptyPtr,
                                          pair
                                      )
                                      swapAmount := sub(balance1, reserve1)
                                  }
                                  let temp := reserve0
                                  reserve0 := reserve1
                                  reserve1 := temp
                              }
                              ret := mul(swapAmount, numerator)
                              ret := div(
                                  mul(ret, reserve1),
                                  add(ret, mul(reserve0, _DENOMINATOR))
                              )
                              mstore(emptyPtr, _SWAP_GETRESERVES_SELECTOR)
                              switch reversed
                              case 0 {
                                  mstore(add(emptyPtr, 0x04), 0)
                                  mstore(add(emptyPtr, 0x24), ret)
                              }
                              default {
                                  mstore(add(emptyPtr, 0x04), ret)
                                  mstore(add(emptyPtr, 0x24), 0)
                              }
                              mstore(add(emptyPtr, 0x44), dst)
                              mstore(add(emptyPtr, 0x64), 0x80)
                              mstore(add(emptyPtr, 0x84), 0)
                              if iszero(call(gas(), pair, 0, emptyPtr, 0xa4, 0, 0)) {
                                  revertWithReason(
                                      0x00000010737761702063616c6c206661696c6564000000000000000000000000,
                                      0x54
                                  ) // "swap call failed"
                              }
                          }
                          let poolsOffset
                          let poolsEndOffset
                          {
                              let len := pools.length
                              poolsOffset := pools.offset //
                              poolsEndOffset := add(poolsOffset, mul(len, 32))
                              if eq(len, 0) {
                                  revertWithReason(
                                      0x000000b656d70747920706f6f6c73000000000000000000000000000000000000,
                                      0x4e
                                  ) // "empty pools"
                              }
                          }
                          let emptyPtr := mload(0x40)
                          let rawPair := calldataload(poolsOffset)
                          switch eq(ETH_ADDRESS, srcToken)
                          case 1 {
                              // require callvalue() >= amount, lt: if x < y return 1,else return 0
                              if eq(lt(callvalue(), amount), 1) {
                                  revertWithReason(
                                      0x00000011696e76616c6964206d73672e76616c75650000000000000000000000,
                                      0x55
                                  ) // "invalid msg.value"
                              }
                              mstore(emptyPtr, _TRANSFER_DEPOSIT_SELECTOR)
                              if iszero(
                                  call(gas(), _WETH, amount, add(emptyPtr, 0x04), 0x4, 0, 0)
                              ) {
                                  revertWithReason(
                                      0x000000126465706f73697420455448206661696c656400000000000000000000,
                                      0x56
                                  ) // "deposit ETH failed"
                              }
                              mstore(add(0x04, emptyPtr), and(rawPair, _ADDRESS_MASK))
                              mstore(add(0x24, emptyPtr), amount)
                              if iszero(call(gas(), _WETH, 0, emptyPtr, 0x44, 0, 0x20)) {
                                  revertWithReason(
                                      0x000000147472616e736665722057455448206661696c65640000000000000000,
                                      0x58
                                  ) // "transfer WETH failed"
                              }
                          }
                          default {
                              if callvalue() {
                                  revertWithReason(
                                      0x00000011696e76616c6964206d73672e76616c75650000000000000000000000,
                                      0x55
                                  ) // "invalid msg.value"
                              }
                              mstore(emptyPtr, _CLAIM_TOKENS_CALL_SELECTOR_32)
                              mstore(add(emptyPtr, 0x4), srcToken)
                              mstore(add(emptyPtr, 0x24), payer)
                              mstore(add(emptyPtr, 0x44), and(rawPair, _ADDRESS_MASK))
                              mstore(add(emptyPtr, 0x64), amount)
                              if iszero(
                                  call(gas(), _APPROVE_PROXY, 0, emptyPtr, 0x84, 0, 0)
                              ) {
                                  revertWithReason(
                                      0x00000012636c61696d20746f6b656e206661696c656400000000000000000000,
                                      0x56
                                  ) // "claim token failed"
                              }
                          }
                          returnAmount := amount
                          for {
                              let i := add(poolsOffset, 0x20)
                          } lt(i, poolsEndOffset) {
                              i := add(i, 0x20)
                          } {
                              let nextRawPair := calldataload(i)
                              returnAmount := swap(
                                  emptyPtr,
                                  returnAmount,
                                  and(rawPair, _ADDRESS_MASK),
                                  and(rawPair, _REVERSE_MASK),
                                  and(rawPair, _IS_TOKEN0_TAX),
                                  and(rawPair, _IS_TOKEN1_TAX),
                                  shr(_NUMERATOR_OFFSET, and(rawPair, _NUMERATOR_MASK)),
                                  and(nextRawPair, _ADDRESS_MASK)
                              )
                              rawPair := nextRawPair
                          }
                          let toToken
                          switch and(rawPair, _WETH_MASK)
                          case 0 {
                              let beforeAmount
                              switch and(rawPair, _REVERSE_MASK)
                              case 0 {
                                  if and(rawPair, _IS_TOKEN1_TAX) {
                                      mstore(emptyPtr, _BALANCEOF_TOKEN1_SELECTOR)
                                      if iszero(
                                          staticcall(
                                              gas(),
                                              and(rawPair, _ADDRESS_MASK),
                                              add(0x04, emptyPtr),
                                              0x04,
                                              0x00,
                                              0x20
                                          )
                                      ) {
                                          revertWithReason(
                                              0x00000012746f6b656e312063616c6c206661696c656400000000000000000000,
                                              0x56
                                          ) // "token1 call failed"
                                      }
                                      toToken := mload(0)
                                      mstore(add(0x04, emptyPtr), receiver)
                                      if iszero(
                                          staticcall(
                                              gas(),
                                              toToken,
                                              emptyPtr,
                                              0x24,
                                              0x00,
                                              0x20
                                          )
                                      ) {
                                          revertWithReason(
                                              0x00000015746f6b656e312062616c616e6365206661696c656400000000000000,
                                              0x59
                                          ) // "token1 balance failed"
                                      }
                                      beforeAmount := mload(0)
                                  }
                              }
                              default {
                                  if and(rawPair, _IS_TOKEN0_TAX) {
                                      mstore(emptyPtr, _BALANCEOF_TOKEN0_SELECTOR)
                                      if iszero(
                                          staticcall(
                                              gas(),
                                              and(rawPair, _ADDRESS_MASK),
                                              add(0x04, emptyPtr),
                                              0x04,
                                              0x00,
                                              0x20
                                          )
                                      ) {
                                          revertWithReason(
                                              0x00000012746f6b656e302063616c6c206661696c656400000000000000000000,
                                              0x56
                                          ) // "token0 call failed"
                                      }
                                      toToken := mload(0)
                                      mstore(add(0x04, emptyPtr), receiver)
                                      if iszero(
                                          staticcall(
                                              gas(),
                                              toToken,
                                              emptyPtr,
                                              0x24,
                                              0x00,
                                              0x20
                                          )
                                      ) {
                                          revertWithReason(
                                              0x00000015746f6b656e302062616c616e6365206661696c656400000000000000,
                                              0x56
                                          ) // "token0 balance failed"
                                      }
                                      beforeAmount := mload(0)
                                  }
                              }
                              returnAmount := swap(
                                  emptyPtr,
                                  returnAmount,
                                  and(rawPair, _ADDRESS_MASK),
                                  and(rawPair, _REVERSE_MASK),
                                  and(rawPair, _IS_TOKEN0_TAX),
                                  and(rawPair, _IS_TOKEN1_TAX),
                                  shr(_NUMERATOR_OFFSET, and(rawPair, _NUMERATOR_MASK)),
                                  receiver
                              )
                              switch lt(0x0, toToken)
                              case 1 {
                                  mstore(emptyPtr, _BALANCEOF_TOKEN0_SELECTOR)
                                  mstore(add(0x04, emptyPtr), receiver)
                                  if iszero(
                                      staticcall(gas(), toToken, emptyPtr, 0x24, 0x00, 0x20)
                                  ) {
                                      revertWithReason(
                                          0x000000146765742062616c616e63654f66206661696c65640000000000000000,
                                          0x58
                                      ) // "get balanceOf failed"
                                  }
                                  returnAmount := sub(mload(0), beforeAmount)
                              }
                              default {
                                  // set token0 addr for the non-safemoon token
                                  switch and(rawPair, _REVERSE_MASK)
                                  case 0 {
                                      // get token1
                                      toToken := _getTokenAddr(
                                          emptyPtr,
                                          and(rawPair, _ADDRESS_MASK),
                                          _BALANCEOF_TOKEN1_SELECTOR
                                      )
                                  }
                                  default {
                                      // get token0
                                      toToken := _getTokenAddr(
                                          emptyPtr,
                                          and(rawPair, _ADDRESS_MASK),
                                          _BALANCEOF_TOKEN0_SELECTOR
                                      )
                                  }
                              }
                          }
                          default {
                              toToken := ETH_ADDRESS
                              returnAmount := swap(
                                  emptyPtr,
                                  returnAmount,
                                  and(rawPair, _ADDRESS_MASK),
                                  and(rawPair, _REVERSE_MASK),
                                  and(rawPair, _IS_TOKEN0_TAX),
                                  and(rawPair, _IS_TOKEN1_TAX),
                                  shr(_NUMERATOR_OFFSET, and(rawPair, _NUMERATOR_MASK)),
                                  address()
                              )
                              mstore(emptyPtr, _WITHDRAW_TRNASFER_SELECTOR)
                              mstore(add(emptyPtr, 0x08), _WNATIVE_RELAY)
                              mstore(add(emptyPtr, 0x28), returnAmount)
                              if iszero(
                                  call(gas(), _WETH, 0, add(0x04, emptyPtr), 0x44, 0, 0x20)
                              ) {
                                  revertWithReason(
                                      0x000000147472616e736665722057455448206661696c65640000000000000000,
                                      0x58
                                  ) // "transfer WETH failed"
                              }
                              mstore(add(emptyPtr, 0x04), returnAmount)
                              if iszero(
                                  call(gas(), _WNATIVE_RELAY, 0, emptyPtr, 0x24, 0, 0x20)
                              ) {
                                  revertWithReason(
                                      0x00000013776974686472617720455448206661696c6564000000000000000000,
                                      0x57
                                  ) // "withdraw ETH failed"
                              }
                              if iszero(call(gas(), receiver, returnAmount, 0, 0, 0, 0)) {
                                  revertWithReason(
                                      0x000000137472616e7366657220455448206661696c6564000000000000000000,
                                      0x57
                                  ) // "transfer ETH failed"
                              }
                          }
                          if lt(returnAmount, minReturn) {
                              revertWithReason(
                                  0x000000164d696e2072657475726e206e6f742072656163686564000000000000,
                                  0x5a
                              ) // "Min return not reached"
                          }
                          // emit event
                          mstore(emptyPtr, srcToken)
                          mstore(add(emptyPtr, 0x20), toToken)
                          mstore(add(emptyPtr, 0x40), origin())
                          mstore(add(emptyPtr, 0x60), amount)
                          mstore(add(emptyPtr, 0x80), returnAmount)
                          log1(
                              emptyPtr,
                              0xa0,
                              0x1bb43f2da90e35f7b0cf38521ca95a49e68eb42fac49924930a5bd73cdf7576c
                          )
                      }
                  }
              }
              /// SPDX-License-Identifier: MIT
              pragma solidity 0.8.17;
              import "./interfaces/IUniswapV3SwapCallback.sol";
              import "./interfaces/IUniV3.sol";
              import "./interfaces/IWETH.sol";
              import "./interfaces/IWNativeRelayer.sol";
              import "./libraries/Address.sol";
              import "./libraries/CommonUtils.sol";
              import "./libraries/RouterErrors.sol";
              import "./libraries/SafeCast.sol";
              contract UnxswapV3Router is IUniswapV3SwapCallback, CommonUtils {
                  using Address for address payable;
                  uint256 private constant _ONE_FOR_ZERO_MASK = 1 << 255; // Mask for identifying if the swap is one-for-zero
                  uint256 private constant _WETH_UNWRAP_MASK = 1 << 253; // Mask for identifying if WETH should be unwrapped to ETH
                  bytes32 private constant _POOL_INIT_CODE_HASH =
                      0xe34f199b19b2b4f47f68442619d555527d244f78a3297ea89325f843f87b8b54; // Pool init code hash
                  bytes32 private constant _FF_FACTORY =
                      0xff1F98431c8aD98523631AE4a59f267346ea31F9840000000000000000000000; // Factory address
                  // concatenation of token0(), token1() fee(), transfer() and claimTokens() selectors
                  bytes32 private constant _SELECTORS =
                      0x0dfe1681d21220a7ddca3f43a9059cbb0a5ea466000000000000000000000000;
                  // concatenation of withdraw(uint),transfer()
                  bytes32 private constant _SELECTORS2 =
                      0x2e1a7d4da9059cbb000000000000000000000000000000000000000000000000;
                  uint160 private constant _MIN_SQRT_RATIO = 4_295_128_739 + 1;
                  uint160 private constant _MAX_SQRT_RATIO =
                      1_461_446_703_485_210_103_287_273_052_203_988_822_378_723_970_342 - 1;
                  bytes32 private constant _SWAP_SELECTOR =
                      0x128acb0800000000000000000000000000000000000000000000000000000000; // Swap function selector
                  uint256 private constant _INT256_MAX =
                      0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff; // Maximum int256
                  uint256 private constant _INT256_MIN =
                      0x8000000000000000000000000000000000000000000000000000000000000000; // Minimum int256
                  /// @notice Conducts a swap using the Uniswap V3 protocol internally within the contract.
                  /// @param payer The address of the account providing the tokens for the swap.
                  /// @param receiver The address that will receive the tokens after the swap.
                  /// @param amount The amount of the source token to be swapped.
                  /// @param minReturn The minimum amount of tokens that must be received for the swap to be valid, safeguarding against excessive slippage.
                  /// @param pools An array of pool identifiers defining the swap route within Uniswap V3.
                  /// @return returnAmount The amount of tokens received from the swap.
                  /// @return srcTokenAddr The address of the source token used for the swap.
                  /// @dev This internal function encapsulates the core logic for executing swaps on Uniswap V3. It is intended to be used by other functions in the contract that prepare and pass the necessary parameters. The function handles the swapping process, ensuring that the minimum return is met and managing the transfer of tokens.
                  function _uniswapV3Swap(
                      address payer,
                      address payable receiver,
                      uint256 amount,
                      uint256 minReturn,
                      uint256[] calldata pools
                  ) internal returns (uint256 returnAmount, address srcTokenAddr) {
                      assembly {
                          function _revertWithReason(m, len) {
                              mstore(
                                  0,
                                  0x08c379a000000000000000000000000000000000000000000000000000000000
                              )
                              mstore(
                                  0x20,
                                  0x0000002000000000000000000000000000000000000000000000000000000000
                              )
                              mstore(0x40, m)
                              revert(0, len)
                          }
                          function _makeSwap(_receiver, _payer, _pool, _amount)
                              -> _returnAmount
                          {
                              if lt(_INT256_MAX, _amount) {
                                  mstore(
                                      0,
                                      0xb3f79fd000000000000000000000000000000000000000000000000000000000
                                  ) //SafeCastToInt256Failed()
                                  revert(0, 4)
                              }
                              let freePtr := mload(0x40)
                              let zeroForOne := eq(and(_pool, _ONE_FOR_ZERO_MASK), 0)
                              let poolAddr := and(_pool, _ADDRESS_MASK)
                              switch zeroForOne
                              case 1 {
                                  mstore(freePtr, _SWAP_SELECTOR)
                                  let paramPtr := add(freePtr, 4)
                                  mstore(paramPtr, _receiver)
                                  mstore(add(paramPtr, 0x20), true)
                                  mstore(add(paramPtr, 0x40), _amount)
                                  mstore(add(paramPtr, 0x60), _MIN_SQRT_RATIO)
                                  mstore(add(paramPtr, 0x80), 0xa0)
                                  mstore(add(paramPtr, 0xa0), 32)
                                  mstore(add(paramPtr, 0xc0), _payer)
                                  let success := call(gas(), poolAddr, 0, freePtr, 0xe4, 0, 0)
                                  if iszero(success) {
                                      revert(0, 32)
                                  }
                                  returndatacopy(0, 32, 32) // only copy _amount1   MEM[0:] <= RETURNDATA[32:32+32]
                              }
                              default {
                                  mstore(freePtr, _SWAP_SELECTOR)
                                  let paramPtr := add(freePtr, 4)
                                  mstore(paramPtr, _receiver)
                                  mstore(add(paramPtr, 0x20), false)
                                  mstore(add(paramPtr, 0x40), _amount)
                                  mstore(add(paramPtr, 0x60), _MAX_SQRT_RATIO)
                                  mstore(add(paramPtr, 0x80), 0xa0)
                                  mstore(add(paramPtr, 0xa0), 32)
                                  mstore(add(paramPtr, 0xc0), _payer)
                                  let success := call(gas(), poolAddr, 0, freePtr, 0xe4, 0, 0)
                                  if iszero(success) {
                                      revert(0, 32)
                                  }
                                  returndatacopy(0, 0, 32) // only copy _amount0   MEM[0:] <= RETURNDATA[0:0+32]
                              }
                              _returnAmount := mload(0)
                              if lt(_returnAmount, _INT256_MIN) {
                                  mstore(
                                      0,
                                      0x88c8ee9c00000000000000000000000000000000000000000000000000000000
                                  ) //SafeCastToUint256Failed()
                                  revert(0, 4)
                              }
                              _returnAmount := add(1, not(_returnAmount)) // -a = ~a + 1
                          }
                          function _wrapWeth(_amount) {
                              // require callvalue() >= amount, lt: if x < y return 1,else return 0
                              if eq(lt(callvalue(), _amount), 1) {
                                  mstore(
                                      0,
                                      0x1841b4e100000000000000000000000000000000000000000000000000000000
                                  ) // InvalidMsgValue()
                                  revert(0, 4)
                              }
                              let success := call(gas(), _WETH, _amount, 0, 0, 0, 0) //进入fallback逻辑
                              if iszero(success) {
                                  _revertWithReason(
                                      0x0000001357455448206465706f736974206661696c6564000000000000000000,
                                      87
                                  ) //WETH deposit failed
                              }
                          }
                          function _unWrapWeth(_receiver, _amount) {
                              let freePtr := mload(0x40)
                              let transferPtr := add(freePtr, 4)
                              mstore(freePtr, _SELECTORS2) // withdraw amountWith to amount
                              // transfer
                              mstore(add(transferPtr, 4), _WNATIVE_RELAY)
                              mstore(add(transferPtr, 36), _amount)
                              let success := call(gas(), _WETH, 0, transferPtr, 68, 0, 0)
                              if iszero(success) {
                                  _revertWithReason(
                                      0x000000147472616e736665722077657468206661696c65640000000000000000,
                                      88
                                  ) // transfer weth failed
                              }
                              // withdraw
                              mstore(add(freePtr, 4), _amount)
                              success := call(gas(), _WNATIVE_RELAY, 0, freePtr, 36, 0, 0)
                              if iszero(success) {
                                  _revertWithReason(
                                      0x0000001477697468647261772077657468206661696c65640000000000000000,
                                      88
                                  ) // withdraw weth failed
                              }
                              // msg.value transfer
                              success := call(gas(), _receiver, _amount, 0, 0, 0, 0)
                              if iszero(success) {
                                  _revertWithReason(
                                      0x0000001173656e64206574686572206661696c65640000000000000000000000,
                                      85
                                  ) // send ether failed
                              }
                          }
                          function _token0(_pool) -> token0 {
                              let freePtr := mload(0x40)
                              mstore(freePtr, _SELECTORS)
                              let success := staticcall(gas(), _pool, freePtr, 0x4, 0, 0)
                              if iszero(success) {
                                  _revertWithReason(
                                      0x0000001167657420746f6b656e30206661696c65640000000000000000000000,
                                      85
                                  ) // get token0 failed
                              }
                              returndatacopy(0, 0, 32)
                              token0 := mload(0)
                          }
                          function _token1(_pool) -> token1 {
                              let freePtr := mload(0x40)
                              mstore(freePtr, _SELECTORS)
                              let success := staticcall(
                                  gas(),
                                  _pool,
                                  add(freePtr, 4),
                                  0x4,
                                  0,
                                  0
                              )
                              if iszero(success) {
                                  _revertWithReason(
                                      0x0000001167657420746f6b656e31206661696c65640000000000000000000000,
                                      84
                                  ) // get token1 failed
                              }
                              returndatacopy(0, 0, 32)
                              token1 := mload(0)
                          }
                          function _emitEvent(
                              _firstPoolStart,
                              _lastPoolStart,
                              _returnAmount,
                              wrapWeth,
                              unwrapWeth
                          ) -> srcToken {
                              srcToken := _ETH
                              let toToken := _ETH
                              if eq(wrapWeth, false) {
                                  let firstPool := calldataload(_firstPoolStart)
                                  switch eq(0, and(firstPool, _ONE_FOR_ZERO_MASK))
                                  case true {
                                      srcToken := _token0(firstPool)
                                  }
                                  default {
                                      srcToken := _token1(firstPool)
                                  }
                              }
                              if eq(unwrapWeth, false) {
                                  let lastPool := calldataload(_lastPoolStart)
                                  switch eq(0, and(lastPool, _ONE_FOR_ZERO_MASK))
                                  case true {
                                      toToken := _token1(lastPool)
                                  }
                                  default {
                                      toToken := _token0(lastPool)
                                  }
                              }
                              let freePtr := mload(0x40)
                              mstore(0, srcToken)
                              mstore(32, toToken)
                              mstore(64, origin())
                              // mstore(96, _initAmount) //avoid stack too deep, since i mstore the initAmount to 96, so no need to re-mstore it
                              mstore(128, _returnAmount)
                              log1(
                                  0,
                                  160,
                                  0x1bb43f2da90e35f7b0cf38521ca95a49e68eb42fac49924930a5bd73cdf7576c
                              )
                              mstore(0x40, freePtr)
                          }
                          let firstPoolStart
                          let lastPoolStart
                          {
                              let len := pools.length
                              firstPoolStart := pools.offset //
                              lastPoolStart := sub(add(firstPoolStart, mul(len, 32)), 32)
                              if eq(len, 0) {
                                  mstore(
                                      0,
                                      0x67e7c0f600000000000000000000000000000000000000000000000000000000
                                  ) // EmptyPools()
                                  revert(0, 4)
                              }
                          }
                          let wrapWeth := gt(callvalue(), 0)
                          if wrapWeth {
                              _wrapWeth(amount)
                              payer := address()
                          }
                          mstore(96, amount) // 96 is not override by _makeSwap, since it only use freePtr memory, and it is not override by unWrapWeth ethier
                          for {
                              let i := firstPoolStart
                          } lt(i, lastPoolStart) {
                              i := add(i, 32)
                          } {
                              amount := _makeSwap(address(), payer, calldataload(i), amount)
                              payer := address()
                          }
                          let unwrapWeth := gt(
                              and(calldataload(lastPoolStart), _WETH_UNWRAP_MASK),
                              0
                          ) // pools[lastIndex] & _WETH_UNWRAP_MASK > 0
                          // last one or only one
                          switch unwrapWeth
                          case 1 {
                              returnAmount := _makeSwap(
                                  address(),
                                  payer,
                                  calldataload(lastPoolStart),
                                  amount
                              )
                              _unWrapWeth(receiver, returnAmount)
                          }
                          case 0 {
                              returnAmount := _makeSwap(
                                  receiver,
                                  payer,
                                  calldataload(lastPoolStart),
                                  amount
                              )
                          }
                          if lt(returnAmount, minReturn) {
                              _revertWithReason(
                                  0x000000164d696e2072657475726e206e6f742072656163686564000000000000,
                                  90
                              ) // Min return not reached
                          }
                          srcTokenAddr := _emitEvent(
                              firstPoolStart,
                              lastPoolStart,
                              returnAmount,
                              wrapWeth,
                              unwrapWeth
                          )
                      }
                  }
                  /// @inheritdoc IUniswapV3SwapCallback
                  function uniswapV3SwapCallback(
                      int256 amount0Delta,
                      int256 amount1Delta,
                      bytes calldata /*data*/
                  ) external override {
                      assembly {
                          // solhint-disable-line no-inline-assembly
                          function reRevert() {
                              returndatacopy(0, 0, returndatasize())
                              revert(0, returndatasize())
                          }
                          function validateERC20Transfer(status) {
                              if iszero(status) {
                                  reRevert()
                              }
                              let success := or(
                                  iszero(returndatasize()), // empty return data
                                  and(gt(returndatasize(), 31), eq(mload(0), 1)) // true in return data
                              )
                              if iszero(success) {
                                  mstore(
                                      0,
                                      0xf27f64e400000000000000000000000000000000000000000000000000000000
                                  ) // ERC20TransferFailed()
                                  revert(0, 4)
                              }
                          }
                          let emptyPtr := mload(0x40)
                          let resultPtr := add(emptyPtr, 21) // 0x15 = _FF_FACTORY size
                          mstore(emptyPtr, _SELECTORS)
                          // token0
                          if iszero(staticcall(gas(), caller(), emptyPtr, 4, 0, 32)) {
                              reRevert()
                          }
                          //token1
                          if iszero(
                              staticcall(gas(), caller(), add(emptyPtr, 4), 4, 32, 32)
                          ) {
                              reRevert()
                          }
                          // fee
                          if iszero(
                              staticcall(gas(), caller(), add(emptyPtr, 8), 4, 64, 32)
                          ) {
                              reRevert()
                          }
                          let token
                          let amount
                          switch sgt(amount0Delta, 0)
                          case 1 {
                              token := mload(0)
                              amount := amount0Delta
                          }
                          default {
                              token := mload(32)
                              amount := amount1Delta
                          }
                          // let salt := keccak256(0, 96)
                          mstore(emptyPtr, _FF_FACTORY)
                          mstore(resultPtr, keccak256(0, 96)) // Compute the inner hash in-place
                          mstore(add(resultPtr, 32), _POOL_INIT_CODE_HASH)
                          let pool := and(keccak256(emptyPtr, 85), _ADDRESS_MASK)
                          if iszero(eq(pool, caller())) {
                              // if xor(pool, caller()) {
                              mstore(
                                  0,
                                  0xb2c0272200000000000000000000000000000000000000000000000000000000
                              ) // BadPool()
                              revert(0, 4)
                          }
                          let payer := calldataload(132) // 4+32+32+32+32 = 132
                          mstore(emptyPtr, _SELECTORS)
                          switch eq(payer, address())
                          case 1 {
                              // token.safeTransfer(msg.sender,amount)
                              mstore(add(emptyPtr, 0x10), caller())
                              mstore(add(emptyPtr, 0x30), amount)
                              validateERC20Transfer(
                                  call(gas(), token, 0, add(emptyPtr, 0x0c), 0x44, 0, 0x20)
                              )
                          }
                          default {
                              // approveProxy.claimTokens(token, payer, msg.sender, amount);
                              mstore(add(emptyPtr, 0x14), token)
                              mstore(add(emptyPtr, 0x34), payer)
                              mstore(add(emptyPtr, 0x54), caller())
                              mstore(add(emptyPtr, 0x74), amount)
                              validateERC20Transfer(
                                  call(
                                      gas(),
                                      _APPROVE_PROXY,
                                      0,
                                      add(emptyPtr, 0x10),
                                      0x84,
                                      0,
                                      0x20
                                  )
                              )
                          }
                      }
                  }
              }
              

              File 3 of 6: WETH9
              // Copyright (C) 2015, 2016, 2017 Dapphub
              
              // This program is free software: you can redistribute it and/or modify
              // it under the terms of the GNU General Public License as published by
              // the Free Software Foundation, either version 3 of the License, or
              // (at your option) any later version.
              
              // This program is distributed in the hope that it will be useful,
              // but WITHOUT ANY WARRANTY; without even the implied warranty of
              // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
              // GNU General Public License for more details.
              
              // You should have received a copy of the GNU General Public License
              // along with this program.  If not, see <http://www.gnu.org/licenses/>.
              
              pragma solidity ^0.4.18;
              
              contract WETH9 {
                  string public name     = "Wrapped Ether";
                  string public symbol   = "WETH";
                  uint8  public decimals = 18;
              
                  event  Approval(address indexed src, address indexed guy, uint wad);
                  event  Transfer(address indexed src, address indexed dst, uint wad);
                  event  Deposit(address indexed dst, uint wad);
                  event  Withdrawal(address indexed src, uint wad);
              
                  mapping (address => uint)                       public  balanceOf;
                  mapping (address => mapping (address => uint))  public  allowance;
              
                  function() public payable {
                      deposit();
                  }
                  function deposit() public payable {
                      balanceOf[msg.sender] += msg.value;
                      Deposit(msg.sender, msg.value);
                  }
                  function withdraw(uint wad) public {
                      require(balanceOf[msg.sender] >= wad);
                      balanceOf[msg.sender] -= wad;
                      msg.sender.transfer(wad);
                      Withdrawal(msg.sender, wad);
                  }
              
                  function totalSupply() public view returns (uint) {
                      return this.balance;
                  }
              
                  function approve(address guy, uint wad) public returns (bool) {
                      allowance[msg.sender][guy] = wad;
                      Approval(msg.sender, guy, wad);
                      return true;
                  }
              
                  function transfer(address dst, uint wad) public returns (bool) {
                      return transferFrom(msg.sender, dst, wad);
                  }
              
                  function transferFrom(address src, address dst, uint wad)
                      public
                      returns (bool)
                  {
                      require(balanceOf[src] >= wad);
              
                      if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
                          require(allowance[src][msg.sender] >= wad);
                          allowance[src][msg.sender] -= wad;
                      }
              
                      balanceOf[src] -= wad;
                      balanceOf[dst] += wad;
              
                      Transfer(src, dst, wad);
              
                      return true;
                  }
              }
              
              
              /*
                                  GNU GENERAL PUBLIC LICENSE
                                     Version 3, 29 June 2007
              
               Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
               Everyone is permitted to copy and distribute verbatim copies
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              File 4 of 6: UniswapV3Pool
              // SPDX-License-Identifier: BUSL-1.1
              pragma solidity =0.7.6;
              import './interfaces/IUniswapV3Pool.sol';
              import './NoDelegateCall.sol';
              import './libraries/LowGasSafeMath.sol';
              import './libraries/SafeCast.sol';
              import './libraries/Tick.sol';
              import './libraries/TickBitmap.sol';
              import './libraries/Position.sol';
              import './libraries/Oracle.sol';
              import './libraries/FullMath.sol';
              import './libraries/FixedPoint128.sol';
              import './libraries/TransferHelper.sol';
              import './libraries/TickMath.sol';
              import './libraries/LiquidityMath.sol';
              import './libraries/SqrtPriceMath.sol';
              import './libraries/SwapMath.sol';
              import './interfaces/IUniswapV3PoolDeployer.sol';
              import './interfaces/IUniswapV3Factory.sol';
              import './interfaces/IERC20Minimal.sol';
              import './interfaces/callback/IUniswapV3MintCallback.sol';
              import './interfaces/callback/IUniswapV3SwapCallback.sol';
              import './interfaces/callback/IUniswapV3FlashCallback.sol';
              contract UniswapV3Pool is IUniswapV3Pool, NoDelegateCall {
                  using LowGasSafeMath for uint256;
                  using LowGasSafeMath for int256;
                  using SafeCast for uint256;
                  using SafeCast for int256;
                  using Tick for mapping(int24 => Tick.Info);
                  using TickBitmap for mapping(int16 => uint256);
                  using Position for mapping(bytes32 => Position.Info);
                  using Position for Position.Info;
                  using Oracle for Oracle.Observation[65535];
                  /// @inheritdoc IUniswapV3PoolImmutables
                  address public immutable override factory;
                  /// @inheritdoc IUniswapV3PoolImmutables
                  address public immutable override token0;
                  /// @inheritdoc IUniswapV3PoolImmutables
                  address public immutable override token1;
                  /// @inheritdoc IUniswapV3PoolImmutables
                  uint24 public immutable override fee;
                  /// @inheritdoc IUniswapV3PoolImmutables
                  int24 public immutable override tickSpacing;
                  /// @inheritdoc IUniswapV3PoolImmutables
                  uint128 public immutable override maxLiquidityPerTick;
                  struct Slot0 {
                      // the current price
                      uint160 sqrtPriceX96;
                      // the current tick
                      int24 tick;
                      // the most-recently updated index of the observations array
                      uint16 observationIndex;
                      // the current maximum number of observations that are being stored
                      uint16 observationCardinality;
                      // the next maximum number of observations to store, triggered in observations.write
                      uint16 observationCardinalityNext;
                      // the current protocol fee as a percentage of the swap fee taken on withdrawal
                      // represented as an integer denominator (1/x)%
                      uint8 feeProtocol;
                      // whether the pool is locked
                      bool unlocked;
                  }
                  /// @inheritdoc IUniswapV3PoolState
                  Slot0 public override slot0;
                  /// @inheritdoc IUniswapV3PoolState
                  uint256 public override feeGrowthGlobal0X128;
                  /// @inheritdoc IUniswapV3PoolState
                  uint256 public override feeGrowthGlobal1X128;
                  // accumulated protocol fees in token0/token1 units
                  struct ProtocolFees {
                      uint128 token0;
                      uint128 token1;
                  }
                  /// @inheritdoc IUniswapV3PoolState
                  ProtocolFees public override protocolFees;
                  /// @inheritdoc IUniswapV3PoolState
                  uint128 public override liquidity;
                  /// @inheritdoc IUniswapV3PoolState
                  mapping(int24 => Tick.Info) public override ticks;
                  /// @inheritdoc IUniswapV3PoolState
                  mapping(int16 => uint256) public override tickBitmap;
                  /// @inheritdoc IUniswapV3PoolState
                  mapping(bytes32 => Position.Info) public override positions;
                  /// @inheritdoc IUniswapV3PoolState
                  Oracle.Observation[65535] public override observations;
                  /// @dev Mutually exclusive reentrancy protection into the pool to/from a method. This method also prevents entrance
                  /// to a function before the pool is initialized. The reentrancy guard is required throughout the contract because
                  /// we use balance checks to determine the payment status of interactions such as mint, swap and flash.
                  modifier lock() {
                      require(slot0.unlocked, 'LOK');
                      slot0.unlocked = false;
                      _;
                      slot0.unlocked = true;
                  }
                  /// @dev Prevents calling a function from anyone except the address returned by IUniswapV3Factory#owner()
                  modifier onlyFactoryOwner() {
                      require(msg.sender == IUniswapV3Factory(factory).owner());
                      _;
                  }
                  constructor() {
                      int24 _tickSpacing;
                      (factory, token0, token1, fee, _tickSpacing) = IUniswapV3PoolDeployer(msg.sender).parameters();
                      tickSpacing = _tickSpacing;
                      maxLiquidityPerTick = Tick.tickSpacingToMaxLiquidityPerTick(_tickSpacing);
                  }
                  /// @dev Common checks for valid tick inputs.
                  function checkTicks(int24 tickLower, int24 tickUpper) private pure {
                      require(tickLower < tickUpper, 'TLU');
                      require(tickLower >= TickMath.MIN_TICK, 'TLM');
                      require(tickUpper <= TickMath.MAX_TICK, 'TUM');
                  }
                  /// @dev Returns the block timestamp truncated to 32 bits, i.e. mod 2**32. This method is overridden in tests.
                  function _blockTimestamp() internal view virtual returns (uint32) {
                      return uint32(block.timestamp); // truncation is desired
                  }
                  /// @dev Get the pool's balance of token0
                  /// @dev This function is gas optimized to avoid a redundant extcodesize check in addition to the returndatasize
                  /// check
                  function balance0() private view returns (uint256) {
                      (bool success, bytes memory data) =
                          token0.staticcall(abi.encodeWithSelector(IERC20Minimal.balanceOf.selector, address(this)));
                      require(success && data.length >= 32);
                      return abi.decode(data, (uint256));
                  }
                  /// @dev Get the pool's balance of token1
                  /// @dev This function is gas optimized to avoid a redundant extcodesize check in addition to the returndatasize
                  /// check
                  function balance1() private view returns (uint256) {
                      (bool success, bytes memory data) =
                          token1.staticcall(abi.encodeWithSelector(IERC20Minimal.balanceOf.selector, address(this)));
                      require(success && data.length >= 32);
                      return abi.decode(data, (uint256));
                  }
                  /// @inheritdoc IUniswapV3PoolDerivedState
                  function snapshotCumulativesInside(int24 tickLower, int24 tickUpper)
                      external
                      view
                      override
                      noDelegateCall
                      returns (
                          int56 tickCumulativeInside,
                          uint160 secondsPerLiquidityInsideX128,
                          uint32 secondsInside
                      )
                  {
                      checkTicks(tickLower, tickUpper);
                      int56 tickCumulativeLower;
                      int56 tickCumulativeUpper;
                      uint160 secondsPerLiquidityOutsideLowerX128;
                      uint160 secondsPerLiquidityOutsideUpperX128;
                      uint32 secondsOutsideLower;
                      uint32 secondsOutsideUpper;
                      {
                          Tick.Info storage lower = ticks[tickLower];
                          Tick.Info storage upper = ticks[tickUpper];
                          bool initializedLower;
                          (tickCumulativeLower, secondsPerLiquidityOutsideLowerX128, secondsOutsideLower, initializedLower) = (
                              lower.tickCumulativeOutside,
                              lower.secondsPerLiquidityOutsideX128,
                              lower.secondsOutside,
                              lower.initialized
                          );
                          require(initializedLower);
                          bool initializedUpper;
                          (tickCumulativeUpper, secondsPerLiquidityOutsideUpperX128, secondsOutsideUpper, initializedUpper) = (
                              upper.tickCumulativeOutside,
                              upper.secondsPerLiquidityOutsideX128,
                              upper.secondsOutside,
                              upper.initialized
                          );
                          require(initializedUpper);
                      }
                      Slot0 memory _slot0 = slot0;
                      if (_slot0.tick < tickLower) {
                          return (
                              tickCumulativeLower - tickCumulativeUpper,
                              secondsPerLiquidityOutsideLowerX128 - secondsPerLiquidityOutsideUpperX128,
                              secondsOutsideLower - secondsOutsideUpper
                          );
                      } else if (_slot0.tick < tickUpper) {
                          uint32 time = _blockTimestamp();
                          (int56 tickCumulative, uint160 secondsPerLiquidityCumulativeX128) =
                              observations.observeSingle(
                                  time,
                                  0,
                                  _slot0.tick,
                                  _slot0.observationIndex,
                                  liquidity,
                                  _slot0.observationCardinality
                              );
                          return (
                              tickCumulative - tickCumulativeLower - tickCumulativeUpper,
                              secondsPerLiquidityCumulativeX128 -
                                  secondsPerLiquidityOutsideLowerX128 -
                                  secondsPerLiquidityOutsideUpperX128,
                              time - secondsOutsideLower - secondsOutsideUpper
                          );
                      } else {
                          return (
                              tickCumulativeUpper - tickCumulativeLower,
                              secondsPerLiquidityOutsideUpperX128 - secondsPerLiquidityOutsideLowerX128,
                              secondsOutsideUpper - secondsOutsideLower
                          );
                      }
                  }
                  /// @inheritdoc IUniswapV3PoolDerivedState
                  function observe(uint32[] calldata secondsAgos)
                      external
                      view
                      override
                      noDelegateCall
                      returns (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s)
                  {
                      return
                          observations.observe(
                              _blockTimestamp(),
                              secondsAgos,
                              slot0.tick,
                              slot0.observationIndex,
                              liquidity,
                              slot0.observationCardinality
                          );
                  }
                  /// @inheritdoc IUniswapV3PoolActions
                  function increaseObservationCardinalityNext(uint16 observationCardinalityNext)
                      external
                      override
                      lock
                      noDelegateCall
                  {
                      uint16 observationCardinalityNextOld = slot0.observationCardinalityNext; // for the event
                      uint16 observationCardinalityNextNew =
                          observations.grow(observationCardinalityNextOld, observationCardinalityNext);
                      slot0.observationCardinalityNext = observationCardinalityNextNew;
                      if (observationCardinalityNextOld != observationCardinalityNextNew)
                          emit IncreaseObservationCardinalityNext(observationCardinalityNextOld, observationCardinalityNextNew);
                  }
                  /// @inheritdoc IUniswapV3PoolActions
                  /// @dev not locked because it initializes unlocked
                  function initialize(uint160 sqrtPriceX96) external override {
                      require(slot0.sqrtPriceX96 == 0, 'AI');
                      int24 tick = TickMath.getTickAtSqrtRatio(sqrtPriceX96);
                      (uint16 cardinality, uint16 cardinalityNext) = observations.initialize(_blockTimestamp());
                      slot0 = Slot0({
                          sqrtPriceX96: sqrtPriceX96,
                          tick: tick,
                          observationIndex: 0,
                          observationCardinality: cardinality,
                          observationCardinalityNext: cardinalityNext,
                          feeProtocol: 0,
                          unlocked: true
                      });
                      emit Initialize(sqrtPriceX96, tick);
                  }
                  struct ModifyPositionParams {
                      // the address that owns the position
                      address owner;
                      // the lower and upper tick of the position
                      int24 tickLower;
                      int24 tickUpper;
                      // any change in liquidity
                      int128 liquidityDelta;
                  }
                  /// @dev Effect some changes to a position
                  /// @param params the position details and the change to the position's liquidity to effect
                  /// @return position a storage pointer referencing the position with the given owner and tick range
                  /// @return amount0 the amount of token0 owed to the pool, negative if the pool should pay the recipient
                  /// @return amount1 the amount of token1 owed to the pool, negative if the pool should pay the recipient
                  function _modifyPosition(ModifyPositionParams memory params)
                      private
                      noDelegateCall
                      returns (
                          Position.Info storage position,
                          int256 amount0,
                          int256 amount1
                      )
                  {
                      checkTicks(params.tickLower, params.tickUpper);
                      Slot0 memory _slot0 = slot0; // SLOAD for gas optimization
                      position = _updatePosition(
                          params.owner,
                          params.tickLower,
                          params.tickUpper,
                          params.liquidityDelta,
                          _slot0.tick
                      );
                      if (params.liquidityDelta != 0) {
                          if (_slot0.tick < params.tickLower) {
                              // current tick is below the passed range; liquidity can only become in range by crossing from left to
                              // right, when we'll need _more_ token0 (it's becoming more valuable) so user must provide it
                              amount0 = SqrtPriceMath.getAmount0Delta(
                                  TickMath.getSqrtRatioAtTick(params.tickLower),
                                  TickMath.getSqrtRatioAtTick(params.tickUpper),
                                  params.liquidityDelta
                              );
                          } else if (_slot0.tick < params.tickUpper) {
                              // current tick is inside the passed range
                              uint128 liquidityBefore = liquidity; // SLOAD for gas optimization
                              // write an oracle entry
                              (slot0.observationIndex, slot0.observationCardinality) = observations.write(
                                  _slot0.observationIndex,
                                  _blockTimestamp(),
                                  _slot0.tick,
                                  liquidityBefore,
                                  _slot0.observationCardinality,
                                  _slot0.observationCardinalityNext
                              );
                              amount0 = SqrtPriceMath.getAmount0Delta(
                                  _slot0.sqrtPriceX96,
                                  TickMath.getSqrtRatioAtTick(params.tickUpper),
                                  params.liquidityDelta
                              );
                              amount1 = SqrtPriceMath.getAmount1Delta(
                                  TickMath.getSqrtRatioAtTick(params.tickLower),
                                  _slot0.sqrtPriceX96,
                                  params.liquidityDelta
                              );
                              liquidity = LiquidityMath.addDelta(liquidityBefore, params.liquidityDelta);
                          } else {
                              // current tick is above the passed range; liquidity can only become in range by crossing from right to
                              // left, when we'll need _more_ token1 (it's becoming more valuable) so user must provide it
                              amount1 = SqrtPriceMath.getAmount1Delta(
                                  TickMath.getSqrtRatioAtTick(params.tickLower),
                                  TickMath.getSqrtRatioAtTick(params.tickUpper),
                                  params.liquidityDelta
                              );
                          }
                      }
                  }
                  /// @dev Gets and updates a position with the given liquidity delta
                  /// @param owner the owner of the position
                  /// @param tickLower the lower tick of the position's tick range
                  /// @param tickUpper the upper tick of the position's tick range
                  /// @param tick the current tick, passed to avoid sloads
                  function _updatePosition(
                      address owner,
                      int24 tickLower,
                      int24 tickUpper,
                      int128 liquidityDelta,
                      int24 tick
                  ) private returns (Position.Info storage position) {
                      position = positions.get(owner, tickLower, tickUpper);
                      uint256 _feeGrowthGlobal0X128 = feeGrowthGlobal0X128; // SLOAD for gas optimization
                      uint256 _feeGrowthGlobal1X128 = feeGrowthGlobal1X128; // SLOAD for gas optimization
                      // if we need to update the ticks, do it
                      bool flippedLower;
                      bool flippedUpper;
                      if (liquidityDelta != 0) {
                          uint32 time = _blockTimestamp();
                          (int56 tickCumulative, uint160 secondsPerLiquidityCumulativeX128) =
                              observations.observeSingle(
                                  time,
                                  0,
                                  slot0.tick,
                                  slot0.observationIndex,
                                  liquidity,
                                  slot0.observationCardinality
                              );
                          flippedLower = ticks.update(
                              tickLower,
                              tick,
                              liquidityDelta,
                              _feeGrowthGlobal0X128,
                              _feeGrowthGlobal1X128,
                              secondsPerLiquidityCumulativeX128,
                              tickCumulative,
                              time,
                              false,
                              maxLiquidityPerTick
                          );
                          flippedUpper = ticks.update(
                              tickUpper,
                              tick,
                              liquidityDelta,
                              _feeGrowthGlobal0X128,
                              _feeGrowthGlobal1X128,
                              secondsPerLiquidityCumulativeX128,
                              tickCumulative,
                              time,
                              true,
                              maxLiquidityPerTick
                          );
                          if (flippedLower) {
                              tickBitmap.flipTick(tickLower, tickSpacing);
                          }
                          if (flippedUpper) {
                              tickBitmap.flipTick(tickUpper, tickSpacing);
                          }
                      }
                      (uint256 feeGrowthInside0X128, uint256 feeGrowthInside1X128) =
                          ticks.getFeeGrowthInside(tickLower, tickUpper, tick, _feeGrowthGlobal0X128, _feeGrowthGlobal1X128);
                      position.update(liquidityDelta, feeGrowthInside0X128, feeGrowthInside1X128);
                      // clear any tick data that is no longer needed
                      if (liquidityDelta < 0) {
                          if (flippedLower) {
                              ticks.clear(tickLower);
                          }
                          if (flippedUpper) {
                              ticks.clear(tickUpper);
                          }
                      }
                  }
                  /// @inheritdoc IUniswapV3PoolActions
                  /// @dev noDelegateCall is applied indirectly via _modifyPosition
                  function mint(
                      address recipient,
                      int24 tickLower,
                      int24 tickUpper,
                      uint128 amount,
                      bytes calldata data
                  ) external override lock returns (uint256 amount0, uint256 amount1) {
                      require(amount > 0);
                      (, int256 amount0Int, int256 amount1Int) =
                          _modifyPosition(
                              ModifyPositionParams({
                                  owner: recipient,
                                  tickLower: tickLower,
                                  tickUpper: tickUpper,
                                  liquidityDelta: int256(amount).toInt128()
                              })
                          );
                      amount0 = uint256(amount0Int);
                      amount1 = uint256(amount1Int);
                      uint256 balance0Before;
                      uint256 balance1Before;
                      if (amount0 > 0) balance0Before = balance0();
                      if (amount1 > 0) balance1Before = balance1();
                      IUniswapV3MintCallback(msg.sender).uniswapV3MintCallback(amount0, amount1, data);
                      if (amount0 > 0) require(balance0Before.add(amount0) <= balance0(), 'M0');
                      if (amount1 > 0) require(balance1Before.add(amount1) <= balance1(), 'M1');
                      emit Mint(msg.sender, recipient, tickLower, tickUpper, amount, amount0, amount1);
                  }
                  /// @inheritdoc IUniswapV3PoolActions
                  function collect(
                      address recipient,
                      int24 tickLower,
                      int24 tickUpper,
                      uint128 amount0Requested,
                      uint128 amount1Requested
                  ) external override lock returns (uint128 amount0, uint128 amount1) {
                      // we don't need to checkTicks here, because invalid positions will never have non-zero tokensOwed{0,1}
                      Position.Info storage position = positions.get(msg.sender, tickLower, tickUpper);
                      amount0 = amount0Requested > position.tokensOwed0 ? position.tokensOwed0 : amount0Requested;
                      amount1 = amount1Requested > position.tokensOwed1 ? position.tokensOwed1 : amount1Requested;
                      if (amount0 > 0) {
                          position.tokensOwed0 -= amount0;
                          TransferHelper.safeTransfer(token0, recipient, amount0);
                      }
                      if (amount1 > 0) {
                          position.tokensOwed1 -= amount1;
                          TransferHelper.safeTransfer(token1, recipient, amount1);
                      }
                      emit Collect(msg.sender, recipient, tickLower, tickUpper, amount0, amount1);
                  }
                  /// @inheritdoc IUniswapV3PoolActions
                  /// @dev noDelegateCall is applied indirectly via _modifyPosition
                  function burn(
                      int24 tickLower,
                      int24 tickUpper,
                      uint128 amount
                  ) external override lock returns (uint256 amount0, uint256 amount1) {
                      (Position.Info storage position, int256 amount0Int, int256 amount1Int) =
                          _modifyPosition(
                              ModifyPositionParams({
                                  owner: msg.sender,
                                  tickLower: tickLower,
                                  tickUpper: tickUpper,
                                  liquidityDelta: -int256(amount).toInt128()
                              })
                          );
                      amount0 = uint256(-amount0Int);
                      amount1 = uint256(-amount1Int);
                      if (amount0 > 0 || amount1 > 0) {
                          (position.tokensOwed0, position.tokensOwed1) = (
                              position.tokensOwed0 + uint128(amount0),
                              position.tokensOwed1 + uint128(amount1)
                          );
                      }
                      emit Burn(msg.sender, tickLower, tickUpper, amount, amount0, amount1);
                  }
                  struct SwapCache {
                      // the protocol fee for the input token
                      uint8 feeProtocol;
                      // liquidity at the beginning of the swap
                      uint128 liquidityStart;
                      // the timestamp of the current block
                      uint32 blockTimestamp;
                      // the current value of the tick accumulator, computed only if we cross an initialized tick
                      int56 tickCumulative;
                      // the current value of seconds per liquidity accumulator, computed only if we cross an initialized tick
                      uint160 secondsPerLiquidityCumulativeX128;
                      // whether we've computed and cached the above two accumulators
                      bool computedLatestObservation;
                  }
                  // the top level state of the swap, the results of which are recorded in storage at the end
                  struct SwapState {
                      // the amount remaining to be swapped in/out of the input/output asset
                      int256 amountSpecifiedRemaining;
                      // the amount already swapped out/in of the output/input asset
                      int256 amountCalculated;
                      // current sqrt(price)
                      uint160 sqrtPriceX96;
                      // the tick associated with the current price
                      int24 tick;
                      // the global fee growth of the input token
                      uint256 feeGrowthGlobalX128;
                      // amount of input token paid as protocol fee
                      uint128 protocolFee;
                      // the current liquidity in range
                      uint128 liquidity;
                  }
                  struct StepComputations {
                      // the price at the beginning of the step
                      uint160 sqrtPriceStartX96;
                      // the next tick to swap to from the current tick in the swap direction
                      int24 tickNext;
                      // whether tickNext is initialized or not
                      bool initialized;
                      // sqrt(price) for the next tick (1/0)
                      uint160 sqrtPriceNextX96;
                      // how much is being swapped in in this step
                      uint256 amountIn;
                      // how much is being swapped out
                      uint256 amountOut;
                      // how much fee is being paid in
                      uint256 feeAmount;
                  }
                  /// @inheritdoc IUniswapV3PoolActions
                  function swap(
                      address recipient,
                      bool zeroForOne,
                      int256 amountSpecified,
                      uint160 sqrtPriceLimitX96,
                      bytes calldata data
                  ) external override noDelegateCall returns (int256 amount0, int256 amount1) {
                      require(amountSpecified != 0, 'AS');
                      Slot0 memory slot0Start = slot0;
                      require(slot0Start.unlocked, 'LOK');
                      require(
                          zeroForOne
                              ? sqrtPriceLimitX96 < slot0Start.sqrtPriceX96 && sqrtPriceLimitX96 > TickMath.MIN_SQRT_RATIO
                              : sqrtPriceLimitX96 > slot0Start.sqrtPriceX96 && sqrtPriceLimitX96 < TickMath.MAX_SQRT_RATIO,
                          'SPL'
                      );
                      slot0.unlocked = false;
                      SwapCache memory cache =
                          SwapCache({
                              liquidityStart: liquidity,
                              blockTimestamp: _blockTimestamp(),
                              feeProtocol: zeroForOne ? (slot0Start.feeProtocol % 16) : (slot0Start.feeProtocol >> 4),
                              secondsPerLiquidityCumulativeX128: 0,
                              tickCumulative: 0,
                              computedLatestObservation: false
                          });
                      bool exactInput = amountSpecified > 0;
                      SwapState memory state =
                          SwapState({
                              amountSpecifiedRemaining: amountSpecified,
                              amountCalculated: 0,
                              sqrtPriceX96: slot0Start.sqrtPriceX96,
                              tick: slot0Start.tick,
                              feeGrowthGlobalX128: zeroForOne ? feeGrowthGlobal0X128 : feeGrowthGlobal1X128,
                              protocolFee: 0,
                              liquidity: cache.liquidityStart
                          });
                      // continue swapping as long as we haven't used the entire input/output and haven't reached the price limit
                      while (state.amountSpecifiedRemaining != 0 && state.sqrtPriceX96 != sqrtPriceLimitX96) {
                          StepComputations memory step;
                          step.sqrtPriceStartX96 = state.sqrtPriceX96;
                          (step.tickNext, step.initialized) = tickBitmap.nextInitializedTickWithinOneWord(
                              state.tick,
                              tickSpacing,
                              zeroForOne
                          );
                          // ensure that we do not overshoot the min/max tick, as the tick bitmap is not aware of these bounds
                          if (step.tickNext < TickMath.MIN_TICK) {
                              step.tickNext = TickMath.MIN_TICK;
                          } else if (step.tickNext > TickMath.MAX_TICK) {
                              step.tickNext = TickMath.MAX_TICK;
                          }
                          // get the price for the next tick
                          step.sqrtPriceNextX96 = TickMath.getSqrtRatioAtTick(step.tickNext);
                          // compute values to swap to the target tick, price limit, or point where input/output amount is exhausted
                          (state.sqrtPriceX96, step.amountIn, step.amountOut, step.feeAmount) = SwapMath.computeSwapStep(
                              state.sqrtPriceX96,
                              (zeroForOne ? step.sqrtPriceNextX96 < sqrtPriceLimitX96 : step.sqrtPriceNextX96 > sqrtPriceLimitX96)
                                  ? sqrtPriceLimitX96
                                  : step.sqrtPriceNextX96,
                              state.liquidity,
                              state.amountSpecifiedRemaining,
                              fee
                          );
                          if (exactInput) {
                              state.amountSpecifiedRemaining -= (step.amountIn + step.feeAmount).toInt256();
                              state.amountCalculated = state.amountCalculated.sub(step.amountOut.toInt256());
                          } else {
                              state.amountSpecifiedRemaining += step.amountOut.toInt256();
                              state.amountCalculated = state.amountCalculated.add((step.amountIn + step.feeAmount).toInt256());
                          }
                          // if the protocol fee is on, calculate how much is owed, decrement feeAmount, and increment protocolFee
                          if (cache.feeProtocol > 0) {
                              uint256 delta = step.feeAmount / cache.feeProtocol;
                              step.feeAmount -= delta;
                              state.protocolFee += uint128(delta);
                          }
                          // update global fee tracker
                          if (state.liquidity > 0)
                              state.feeGrowthGlobalX128 += FullMath.mulDiv(step.feeAmount, FixedPoint128.Q128, state.liquidity);
                          // shift tick if we reached the next price
                          if (state.sqrtPriceX96 == step.sqrtPriceNextX96) {
                              // if the tick is initialized, run the tick transition
                              if (step.initialized) {
                                  // check for the placeholder value, which we replace with the actual value the first time the swap
                                  // crosses an initialized tick
                                  if (!cache.computedLatestObservation) {
                                      (cache.tickCumulative, cache.secondsPerLiquidityCumulativeX128) = observations.observeSingle(
                                          cache.blockTimestamp,
                                          0,
                                          slot0Start.tick,
                                          slot0Start.observationIndex,
                                          cache.liquidityStart,
                                          slot0Start.observationCardinality
                                      );
                                      cache.computedLatestObservation = true;
                                  }
                                  int128 liquidityNet =
                                      ticks.cross(
                                          step.tickNext,
                                          (zeroForOne ? state.feeGrowthGlobalX128 : feeGrowthGlobal0X128),
                                          (zeroForOne ? feeGrowthGlobal1X128 : state.feeGrowthGlobalX128),
                                          cache.secondsPerLiquidityCumulativeX128,
                                          cache.tickCumulative,
                                          cache.blockTimestamp
                                      );
                                  // if we're moving leftward, we interpret liquidityNet as the opposite sign
                                  // safe because liquidityNet cannot be type(int128).min
                                  if (zeroForOne) liquidityNet = -liquidityNet;
                                  state.liquidity = LiquidityMath.addDelta(state.liquidity, liquidityNet);
                              }
                              state.tick = zeroForOne ? step.tickNext - 1 : step.tickNext;
                          } else if (state.sqrtPriceX96 != step.sqrtPriceStartX96) {
                              // recompute unless we're on a lower tick boundary (i.e. already transitioned ticks), and haven't moved
                              state.tick = TickMath.getTickAtSqrtRatio(state.sqrtPriceX96);
                          }
                      }
                      // update tick and write an oracle entry if the tick change
                      if (state.tick != slot0Start.tick) {
                          (uint16 observationIndex, uint16 observationCardinality) =
                              observations.write(
                                  slot0Start.observationIndex,
                                  cache.blockTimestamp,
                                  slot0Start.tick,
                                  cache.liquidityStart,
                                  slot0Start.observationCardinality,
                                  slot0Start.observationCardinalityNext
                              );
                          (slot0.sqrtPriceX96, slot0.tick, slot0.observationIndex, slot0.observationCardinality) = (
                              state.sqrtPriceX96,
                              state.tick,
                              observationIndex,
                              observationCardinality
                          );
                      } else {
                          // otherwise just update the price
                          slot0.sqrtPriceX96 = state.sqrtPriceX96;
                      }
                      // update liquidity if it changed
                      if (cache.liquidityStart != state.liquidity) liquidity = state.liquidity;
                      // update fee growth global and, if necessary, protocol fees
                      // overflow is acceptable, protocol has to withdraw before it hits type(uint128).max fees
                      if (zeroForOne) {
                          feeGrowthGlobal0X128 = state.feeGrowthGlobalX128;
                          if (state.protocolFee > 0) protocolFees.token0 += state.protocolFee;
                      } else {
                          feeGrowthGlobal1X128 = state.feeGrowthGlobalX128;
                          if (state.protocolFee > 0) protocolFees.token1 += state.protocolFee;
                      }
                      (amount0, amount1) = zeroForOne == exactInput
                          ? (amountSpecified - state.amountSpecifiedRemaining, state.amountCalculated)
                          : (state.amountCalculated, amountSpecified - state.amountSpecifiedRemaining);
                      // do the transfers and collect payment
                      if (zeroForOne) {
                          if (amount1 < 0) TransferHelper.safeTransfer(token1, recipient, uint256(-amount1));
                          uint256 balance0Before = balance0();
                          IUniswapV3SwapCallback(msg.sender).uniswapV3SwapCallback(amount0, amount1, data);
                          require(balance0Before.add(uint256(amount0)) <= balance0(), 'IIA');
                      } else {
                          if (amount0 < 0) TransferHelper.safeTransfer(token0, recipient, uint256(-amount0));
                          uint256 balance1Before = balance1();
                          IUniswapV3SwapCallback(msg.sender).uniswapV3SwapCallback(amount0, amount1, data);
                          require(balance1Before.add(uint256(amount1)) <= balance1(), 'IIA');
                      }
                      emit Swap(msg.sender, recipient, amount0, amount1, state.sqrtPriceX96, state.liquidity, state.tick);
                      slot0.unlocked = true;
                  }
                  /// @inheritdoc IUniswapV3PoolActions
                  function flash(
                      address recipient,
                      uint256 amount0,
                      uint256 amount1,
                      bytes calldata data
                  ) external override lock noDelegateCall {
                      uint128 _liquidity = liquidity;
                      require(_liquidity > 0, 'L');
                      uint256 fee0 = FullMath.mulDivRoundingUp(amount0, fee, 1e6);
                      uint256 fee1 = FullMath.mulDivRoundingUp(amount1, fee, 1e6);
                      uint256 balance0Before = balance0();
                      uint256 balance1Before = balance1();
                      if (amount0 > 0) TransferHelper.safeTransfer(token0, recipient, amount0);
                      if (amount1 > 0) TransferHelper.safeTransfer(token1, recipient, amount1);
                      IUniswapV3FlashCallback(msg.sender).uniswapV3FlashCallback(fee0, fee1, data);
                      uint256 balance0After = balance0();
                      uint256 balance1After = balance1();
                      require(balance0Before.add(fee0) <= balance0After, 'F0');
                      require(balance1Before.add(fee1) <= balance1After, 'F1');
                      // sub is safe because we know balanceAfter is gt balanceBefore by at least fee
                      uint256 paid0 = balance0After - balance0Before;
                      uint256 paid1 = balance1After - balance1Before;
                      if (paid0 > 0) {
                          uint8 feeProtocol0 = slot0.feeProtocol % 16;
                          uint256 fees0 = feeProtocol0 == 0 ? 0 : paid0 / feeProtocol0;
                          if (uint128(fees0) > 0) protocolFees.token0 += uint128(fees0);
                          feeGrowthGlobal0X128 += FullMath.mulDiv(paid0 - fees0, FixedPoint128.Q128, _liquidity);
                      }
                      if (paid1 > 0) {
                          uint8 feeProtocol1 = slot0.feeProtocol >> 4;
                          uint256 fees1 = feeProtocol1 == 0 ? 0 : paid1 / feeProtocol1;
                          if (uint128(fees1) > 0) protocolFees.token1 += uint128(fees1);
                          feeGrowthGlobal1X128 += FullMath.mulDiv(paid1 - fees1, FixedPoint128.Q128, _liquidity);
                      }
                      emit Flash(msg.sender, recipient, amount0, amount1, paid0, paid1);
                  }
                  /// @inheritdoc IUniswapV3PoolOwnerActions
                  function setFeeProtocol(uint8 feeProtocol0, uint8 feeProtocol1) external override lock onlyFactoryOwner {
                      require(
                          (feeProtocol0 == 0 || (feeProtocol0 >= 4 && feeProtocol0 <= 10)) &&
                              (feeProtocol1 == 0 || (feeProtocol1 >= 4 && feeProtocol1 <= 10))
                      );
                      uint8 feeProtocolOld = slot0.feeProtocol;
                      slot0.feeProtocol = feeProtocol0 + (feeProtocol1 << 4);
                      emit SetFeeProtocol(feeProtocolOld % 16, feeProtocolOld >> 4, feeProtocol0, feeProtocol1);
                  }
                  /// @inheritdoc IUniswapV3PoolOwnerActions
                  function collectProtocol(
                      address recipient,
                      uint128 amount0Requested,
                      uint128 amount1Requested
                  ) external override lock onlyFactoryOwner returns (uint128 amount0, uint128 amount1) {
                      amount0 = amount0Requested > protocolFees.token0 ? protocolFees.token0 : amount0Requested;
                      amount1 = amount1Requested > protocolFees.token1 ? protocolFees.token1 : amount1Requested;
                      if (amount0 > 0) {
                          if (amount0 == protocolFees.token0) amount0--; // ensure that the slot is not cleared, for gas savings
                          protocolFees.token0 -= amount0;
                          TransferHelper.safeTransfer(token0, recipient, amount0);
                      }
                      if (amount1 > 0) {
                          if (amount1 == protocolFees.token1) amount1--; // ensure that the slot is not cleared, for gas savings
                          protocolFees.token1 -= amount1;
                          TransferHelper.safeTransfer(token1, recipient, amount1);
                      }
                      emit CollectProtocol(msg.sender, recipient, amount0, amount1);
                  }
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              import './pool/IUniswapV3PoolImmutables.sol';
              import './pool/IUniswapV3PoolState.sol';
              import './pool/IUniswapV3PoolDerivedState.sol';
              import './pool/IUniswapV3PoolActions.sol';
              import './pool/IUniswapV3PoolOwnerActions.sol';
              import './pool/IUniswapV3PoolEvents.sol';
              /// @title The interface for a Uniswap V3 Pool
              /// @notice A Uniswap pool facilitates swapping and automated market making between any two assets that strictly conform
              /// to the ERC20 specification
              /// @dev The pool interface is broken up into many smaller pieces
              interface IUniswapV3Pool is
                  IUniswapV3PoolImmutables,
                  IUniswapV3PoolState,
                  IUniswapV3PoolDerivedState,
                  IUniswapV3PoolActions,
                  IUniswapV3PoolOwnerActions,
                  IUniswapV3PoolEvents
              {
              }
              // SPDX-License-Identifier: BUSL-1.1
              pragma solidity =0.7.6;
              /// @title Prevents delegatecall to a contract
              /// @notice Base contract that provides a modifier for preventing delegatecall to methods in a child contract
              abstract contract NoDelegateCall {
                  /// @dev The original address of this contract
                  address private immutable original;
                  constructor() {
                      // Immutables are computed in the init code of the contract, and then inlined into the deployed bytecode.
                      // In other words, this variable won't change when it's checked at runtime.
                      original = address(this);
                  }
                  /// @dev Private method is used instead of inlining into modifier because modifiers are copied into each method,
                  ///     and the use of immutable means the address bytes are copied in every place the modifier is used.
                  function checkNotDelegateCall() private view {
                      require(address(this) == original);
                  }
                  /// @notice Prevents delegatecall into the modified method
                  modifier noDelegateCall() {
                      checkNotDelegateCall();
                      _;
                  }
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.7.0;
              /// @title Optimized overflow and underflow safe math operations
              /// @notice Contains methods for doing math operations that revert on overflow or underflow for minimal gas cost
              library LowGasSafeMath {
                  /// @notice Returns x + y, reverts if sum overflows uint256
                  /// @param x The augend
                  /// @param y The addend
                  /// @return z The sum of x and y
                  function add(uint256 x, uint256 y) internal pure returns (uint256 z) {
                      require((z = x + y) >= x);
                  }
                  /// @notice Returns x - y, reverts if underflows
                  /// @param x The minuend
                  /// @param y The subtrahend
                  /// @return z The difference of x and y
                  function sub(uint256 x, uint256 y) internal pure returns (uint256 z) {
                      require((z = x - y) <= x);
                  }
                  /// @notice Returns x * y, reverts if overflows
                  /// @param x The multiplicand
                  /// @param y The multiplier
                  /// @return z The product of x and y
                  function mul(uint256 x, uint256 y) internal pure returns (uint256 z) {
                      require(x == 0 || (z = x * y) / x == y);
                  }
                  /// @notice Returns x + y, reverts if overflows or underflows
                  /// @param x The augend
                  /// @param y The addend
                  /// @return z The sum of x and y
                  function add(int256 x, int256 y) internal pure returns (int256 z) {
                      require((z = x + y) >= x == (y >= 0));
                  }
                  /// @notice Returns x - y, reverts if overflows or underflows
                  /// @param x The minuend
                  /// @param y The subtrahend
                  /// @return z The difference of x and y
                  function sub(int256 x, int256 y) internal pure returns (int256 z) {
                      require((z = x - y) <= x == (y >= 0));
                  }
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Safe casting methods
              /// @notice Contains methods for safely casting between types
              library SafeCast {
                  /// @notice Cast a uint256 to a uint160, revert on overflow
                  /// @param y The uint256 to be downcasted
                  /// @return z The downcasted integer, now type uint160
                  function toUint160(uint256 y) internal pure returns (uint160 z) {
                      require((z = uint160(y)) == y);
                  }
                  /// @notice Cast a int256 to a int128, revert on overflow or underflow
                  /// @param y The int256 to be downcasted
                  /// @return z The downcasted integer, now type int128
                  function toInt128(int256 y) internal pure returns (int128 z) {
                      require((z = int128(y)) == y);
                  }
                  /// @notice Cast a uint256 to a int256, revert on overflow
                  /// @param y The uint256 to be casted
                  /// @return z The casted integer, now type int256
                  function toInt256(uint256 y) internal pure returns (int256 z) {
                      require(y < 2**255);
                      z = int256(y);
                  }
              }
              // SPDX-License-Identifier: BUSL-1.1
              pragma solidity >=0.5.0;
              import './LowGasSafeMath.sol';
              import './SafeCast.sol';
              import './TickMath.sol';
              import './LiquidityMath.sol';
              /// @title Tick
              /// @notice Contains functions for managing tick processes and relevant calculations
              library Tick {
                  using LowGasSafeMath for int256;
                  using SafeCast for int256;
                  // info stored for each initialized individual tick
                  struct Info {
                      // the total position liquidity that references this tick
                      uint128 liquidityGross;
                      // amount of net liquidity added (subtracted) when tick is crossed from left to right (right to left),
                      int128 liquidityNet;
                      // fee growth per unit of liquidity on the _other_ side of this tick (relative to the current tick)
                      // only has relative meaning, not absolute — the value depends on when the tick is initialized
                      uint256 feeGrowthOutside0X128;
                      uint256 feeGrowthOutside1X128;
                      // the cumulative tick value on the other side of the tick
                      int56 tickCumulativeOutside;
                      // the seconds per unit of liquidity on the _other_ side of this tick (relative to the current tick)
                      // only has relative meaning, not absolute — the value depends on when the tick is initialized
                      uint160 secondsPerLiquidityOutsideX128;
                      // the seconds spent on the other side of the tick (relative to the current tick)
                      // only has relative meaning, not absolute — the value depends on when the tick is initialized
                      uint32 secondsOutside;
                      // true iff the tick is initialized, i.e. the value is exactly equivalent to the expression liquidityGross != 0
                      // these 8 bits are set to prevent fresh sstores when crossing newly initialized ticks
                      bool initialized;
                  }
                  /// @notice Derives max liquidity per tick from given tick spacing
                  /// @dev Executed within the pool constructor
                  /// @param tickSpacing The amount of required tick separation, realized in multiples of `tickSpacing`
                  ///     e.g., a tickSpacing of 3 requires ticks to be initialized every 3rd tick i.e., ..., -6, -3, 0, 3, 6, ...
                  /// @return The max liquidity per tick
                  function tickSpacingToMaxLiquidityPerTick(int24 tickSpacing) internal pure returns (uint128) {
                      int24 minTick = (TickMath.MIN_TICK / tickSpacing) * tickSpacing;
                      int24 maxTick = (TickMath.MAX_TICK / tickSpacing) * tickSpacing;
                      uint24 numTicks = uint24((maxTick - minTick) / tickSpacing) + 1;
                      return type(uint128).max / numTicks;
                  }
                  /// @notice Retrieves fee growth data
                  /// @param self The mapping containing all tick information for initialized ticks
                  /// @param tickLower The lower tick boundary of the position
                  /// @param tickUpper The upper tick boundary of the position
                  /// @param tickCurrent The current tick
                  /// @param feeGrowthGlobal0X128 The all-time global fee growth, per unit of liquidity, in token0
                  /// @param feeGrowthGlobal1X128 The all-time global fee growth, per unit of liquidity, in token1
                  /// @return feeGrowthInside0X128 The all-time fee growth in token0, per unit of liquidity, inside the position's tick boundaries
                  /// @return feeGrowthInside1X128 The all-time fee growth in token1, per unit of liquidity, inside the position's tick boundaries
                  function getFeeGrowthInside(
                      mapping(int24 => Tick.Info) storage self,
                      int24 tickLower,
                      int24 tickUpper,
                      int24 tickCurrent,
                      uint256 feeGrowthGlobal0X128,
                      uint256 feeGrowthGlobal1X128
                  ) internal view returns (uint256 feeGrowthInside0X128, uint256 feeGrowthInside1X128) {
                      Info storage lower = self[tickLower];
                      Info storage upper = self[tickUpper];
                      // calculate fee growth below
                      uint256 feeGrowthBelow0X128;
                      uint256 feeGrowthBelow1X128;
                      if (tickCurrent >= tickLower) {
                          feeGrowthBelow0X128 = lower.feeGrowthOutside0X128;
                          feeGrowthBelow1X128 = lower.feeGrowthOutside1X128;
                      } else {
                          feeGrowthBelow0X128 = feeGrowthGlobal0X128 - lower.feeGrowthOutside0X128;
                          feeGrowthBelow1X128 = feeGrowthGlobal1X128 - lower.feeGrowthOutside1X128;
                      }
                      // calculate fee growth above
                      uint256 feeGrowthAbove0X128;
                      uint256 feeGrowthAbove1X128;
                      if (tickCurrent < tickUpper) {
                          feeGrowthAbove0X128 = upper.feeGrowthOutside0X128;
                          feeGrowthAbove1X128 = upper.feeGrowthOutside1X128;
                      } else {
                          feeGrowthAbove0X128 = feeGrowthGlobal0X128 - upper.feeGrowthOutside0X128;
                          feeGrowthAbove1X128 = feeGrowthGlobal1X128 - upper.feeGrowthOutside1X128;
                      }
                      feeGrowthInside0X128 = feeGrowthGlobal0X128 - feeGrowthBelow0X128 - feeGrowthAbove0X128;
                      feeGrowthInside1X128 = feeGrowthGlobal1X128 - feeGrowthBelow1X128 - feeGrowthAbove1X128;
                  }
                  /// @notice Updates a tick and returns true if the tick was flipped from initialized to uninitialized, or vice versa
                  /// @param self The mapping containing all tick information for initialized ticks
                  /// @param tick The tick that will be updated
                  /// @param tickCurrent The current tick
                  /// @param liquidityDelta A new amount of liquidity to be added (subtracted) when tick is crossed from left to right (right to left)
                  /// @param feeGrowthGlobal0X128 The all-time global fee growth, per unit of liquidity, in token0
                  /// @param feeGrowthGlobal1X128 The all-time global fee growth, per unit of liquidity, in token1
                  /// @param secondsPerLiquidityCumulativeX128 The all-time seconds per max(1, liquidity) of the pool
                  /// @param time The current block timestamp cast to a uint32
                  /// @param upper true for updating a position's upper tick, or false for updating a position's lower tick
                  /// @param maxLiquidity The maximum liquidity allocation for a single tick
                  /// @return flipped Whether the tick was flipped from initialized to uninitialized, or vice versa
                  function update(
                      mapping(int24 => Tick.Info) storage self,
                      int24 tick,
                      int24 tickCurrent,
                      int128 liquidityDelta,
                      uint256 feeGrowthGlobal0X128,
                      uint256 feeGrowthGlobal1X128,
                      uint160 secondsPerLiquidityCumulativeX128,
                      int56 tickCumulative,
                      uint32 time,
                      bool upper,
                      uint128 maxLiquidity
                  ) internal returns (bool flipped) {
                      Tick.Info storage info = self[tick];
                      uint128 liquidityGrossBefore = info.liquidityGross;
                      uint128 liquidityGrossAfter = LiquidityMath.addDelta(liquidityGrossBefore, liquidityDelta);
                      require(liquidityGrossAfter <= maxLiquidity, 'LO');
                      flipped = (liquidityGrossAfter == 0) != (liquidityGrossBefore == 0);
                      if (liquidityGrossBefore == 0) {
                          // by convention, we assume that all growth before a tick was initialized happened _below_ the tick
                          if (tick <= tickCurrent) {
                              info.feeGrowthOutside0X128 = feeGrowthGlobal0X128;
                              info.feeGrowthOutside1X128 = feeGrowthGlobal1X128;
                              info.secondsPerLiquidityOutsideX128 = secondsPerLiquidityCumulativeX128;
                              info.tickCumulativeOutside = tickCumulative;
                              info.secondsOutside = time;
                          }
                          info.initialized = true;
                      }
                      info.liquidityGross = liquidityGrossAfter;
                      // when the lower (upper) tick is crossed left to right (right to left), liquidity must be added (removed)
                      info.liquidityNet = upper
                          ? int256(info.liquidityNet).sub(liquidityDelta).toInt128()
                          : int256(info.liquidityNet).add(liquidityDelta).toInt128();
                  }
                  /// @notice Clears tick data
                  /// @param self The mapping containing all initialized tick information for initialized ticks
                  /// @param tick The tick that will be cleared
                  function clear(mapping(int24 => Tick.Info) storage self, int24 tick) internal {
                      delete self[tick];
                  }
                  /// @notice Transitions to next tick as needed by price movement
                  /// @param self The mapping containing all tick information for initialized ticks
                  /// @param tick The destination tick of the transition
                  /// @param feeGrowthGlobal0X128 The all-time global fee growth, per unit of liquidity, in token0
                  /// @param feeGrowthGlobal1X128 The all-time global fee growth, per unit of liquidity, in token1
                  /// @param secondsPerLiquidityCumulativeX128 The current seconds per liquidity
                  /// @param time The current block.timestamp
                  /// @return liquidityNet The amount of liquidity added (subtracted) when tick is crossed from left to right (right to left)
                  function cross(
                      mapping(int24 => Tick.Info) storage self,
                      int24 tick,
                      uint256 feeGrowthGlobal0X128,
                      uint256 feeGrowthGlobal1X128,
                      uint160 secondsPerLiquidityCumulativeX128,
                      int56 tickCumulative,
                      uint32 time
                  ) internal returns (int128 liquidityNet) {
                      Tick.Info storage info = self[tick];
                      info.feeGrowthOutside0X128 = feeGrowthGlobal0X128 - info.feeGrowthOutside0X128;
                      info.feeGrowthOutside1X128 = feeGrowthGlobal1X128 - info.feeGrowthOutside1X128;
                      info.secondsPerLiquidityOutsideX128 = secondsPerLiquidityCumulativeX128 - info.secondsPerLiquidityOutsideX128;
                      info.tickCumulativeOutside = tickCumulative - info.tickCumulativeOutside;
                      info.secondsOutside = time - info.secondsOutside;
                      liquidityNet = info.liquidityNet;
                  }
              }
              // SPDX-License-Identifier: BUSL-1.1
              pragma solidity >=0.5.0;
              import './BitMath.sol';
              /// @title Packed tick initialized state library
              /// @notice Stores a packed mapping of tick index to its initialized state
              /// @dev The mapping uses int16 for keys since ticks are represented as int24 and there are 256 (2^8) values per word.
              library TickBitmap {
                  /// @notice Computes the position in the mapping where the initialized bit for a tick lives
                  /// @param tick The tick for which to compute the position
                  /// @return wordPos The key in the mapping containing the word in which the bit is stored
                  /// @return bitPos The bit position in the word where the flag is stored
                  function position(int24 tick) private pure returns (int16 wordPos, uint8 bitPos) {
                      wordPos = int16(tick >> 8);
                      bitPos = uint8(tick % 256);
                  }
                  /// @notice Flips the initialized state for a given tick from false to true, or vice versa
                  /// @param self The mapping in which to flip the tick
                  /// @param tick The tick to flip
                  /// @param tickSpacing The spacing between usable ticks
                  function flipTick(
                      mapping(int16 => uint256) storage self,
                      int24 tick,
                      int24 tickSpacing
                  ) internal {
                      require(tick % tickSpacing == 0); // ensure that the tick is spaced
                      (int16 wordPos, uint8 bitPos) = position(tick / tickSpacing);
                      uint256 mask = 1 << bitPos;
                      self[wordPos] ^= mask;
                  }
                  /// @notice Returns the next initialized tick contained in the same word (or adjacent word) as the tick that is either
                  /// to the left (less than or equal to) or right (greater than) of the given tick
                  /// @param self The mapping in which to compute the next initialized tick
                  /// @param tick The starting tick
                  /// @param tickSpacing The spacing between usable ticks
                  /// @param lte Whether to search for the next initialized tick to the left (less than or equal to the starting tick)
                  /// @return next The next initialized or uninitialized tick up to 256 ticks away from the current tick
                  /// @return initialized Whether the next tick is initialized, as the function only searches within up to 256 ticks
                  function nextInitializedTickWithinOneWord(
                      mapping(int16 => uint256) storage self,
                      int24 tick,
                      int24 tickSpacing,
                      bool lte
                  ) internal view returns (int24 next, bool initialized) {
                      int24 compressed = tick / tickSpacing;
                      if (tick < 0 && tick % tickSpacing != 0) compressed--; // round towards negative infinity
                      if (lte) {
                          (int16 wordPos, uint8 bitPos) = position(compressed);
                          // all the 1s at or to the right of the current bitPos
                          uint256 mask = (1 << bitPos) - 1 + (1 << bitPos);
                          uint256 masked = self[wordPos] & mask;
                          // if there are no initialized ticks to the right of or at the current tick, return rightmost in the word
                          initialized = masked != 0;
                          // overflow/underflow is possible, but prevented externally by limiting both tickSpacing and tick
                          next = initialized
                              ? (compressed - int24(bitPos - BitMath.mostSignificantBit(masked))) * tickSpacing
                              : (compressed - int24(bitPos)) * tickSpacing;
                      } else {
                          // start from the word of the next tick, since the current tick state doesn't matter
                          (int16 wordPos, uint8 bitPos) = position(compressed + 1);
                          // all the 1s at or to the left of the bitPos
                          uint256 mask = ~((1 << bitPos) - 1);
                          uint256 masked = self[wordPos] & mask;
                          // if there are no initialized ticks to the left of the current tick, return leftmost in the word
                          initialized = masked != 0;
                          // overflow/underflow is possible, but prevented externally by limiting both tickSpacing and tick
                          next = initialized
                              ? (compressed + 1 + int24(BitMath.leastSignificantBit(masked) - bitPos)) * tickSpacing
                              : (compressed + 1 + int24(type(uint8).max - bitPos)) * tickSpacing;
                      }
                  }
              }
              // SPDX-License-Identifier: BUSL-1.1
              pragma solidity >=0.5.0;
              import './FullMath.sol';
              import './FixedPoint128.sol';
              import './LiquidityMath.sol';
              /// @title Position
              /// @notice Positions represent an owner address' liquidity between a lower and upper tick boundary
              /// @dev Positions store additional state for tracking fees owed to the position
              library Position {
                  // info stored for each user's position
                  struct Info {
                      // the amount of liquidity owned by this position
                      uint128 liquidity;
                      // fee growth per unit of liquidity as of the last update to liquidity or fees owed
                      uint256 feeGrowthInside0LastX128;
                      uint256 feeGrowthInside1LastX128;
                      // the fees owed to the position owner in token0/token1
                      uint128 tokensOwed0;
                      uint128 tokensOwed1;
                  }
                  /// @notice Returns the Info struct of a position, given an owner and position boundaries
                  /// @param self The mapping containing all user positions
                  /// @param owner The address of the position owner
                  /// @param tickLower The lower tick boundary of the position
                  /// @param tickUpper The upper tick boundary of the position
                  /// @return position The position info struct of the given owners' position
                  function get(
                      mapping(bytes32 => Info) storage self,
                      address owner,
                      int24 tickLower,
                      int24 tickUpper
                  ) internal view returns (Position.Info storage position) {
                      position = self[keccak256(abi.encodePacked(owner, tickLower, tickUpper))];
                  }
                  /// @notice Credits accumulated fees to a user's position
                  /// @param self The individual position to update
                  /// @param liquidityDelta The change in pool liquidity as a result of the position update
                  /// @param feeGrowthInside0X128 The all-time fee growth in token0, per unit of liquidity, inside the position's tick boundaries
                  /// @param feeGrowthInside1X128 The all-time fee growth in token1, per unit of liquidity, inside the position's tick boundaries
                  function update(
                      Info storage self,
                      int128 liquidityDelta,
                      uint256 feeGrowthInside0X128,
                      uint256 feeGrowthInside1X128
                  ) internal {
                      Info memory _self = self;
                      uint128 liquidityNext;
                      if (liquidityDelta == 0) {
                          require(_self.liquidity > 0, 'NP'); // disallow pokes for 0 liquidity positions
                          liquidityNext = _self.liquidity;
                      } else {
                          liquidityNext = LiquidityMath.addDelta(_self.liquidity, liquidityDelta);
                      }
                      // calculate accumulated fees
                      uint128 tokensOwed0 =
                          uint128(
                              FullMath.mulDiv(
                                  feeGrowthInside0X128 - _self.feeGrowthInside0LastX128,
                                  _self.liquidity,
                                  FixedPoint128.Q128
                              )
                          );
                      uint128 tokensOwed1 =
                          uint128(
                              FullMath.mulDiv(
                                  feeGrowthInside1X128 - _self.feeGrowthInside1LastX128,
                                  _self.liquidity,
                                  FixedPoint128.Q128
                              )
                          );
                      // update the position
                      if (liquidityDelta != 0) self.liquidity = liquidityNext;
                      self.feeGrowthInside0LastX128 = feeGrowthInside0X128;
                      self.feeGrowthInside1LastX128 = feeGrowthInside1X128;
                      if (tokensOwed0 > 0 || tokensOwed1 > 0) {
                          // overflow is acceptable, have to withdraw before you hit type(uint128).max fees
                          self.tokensOwed0 += tokensOwed0;
                          self.tokensOwed1 += tokensOwed1;
                      }
                  }
              }
              // SPDX-License-Identifier: BUSL-1.1
              pragma solidity >=0.5.0;
              /// @title Oracle
              /// @notice Provides price and liquidity data useful for a wide variety of system designs
              /// @dev Instances of stored oracle data, "observations", are collected in the oracle array
              /// Every pool is initialized with an oracle array length of 1. Anyone can pay the SSTOREs to increase the
              /// maximum length of the oracle array. New slots will be added when the array is fully populated.
              /// Observations are overwritten when the full length of the oracle array is populated.
              /// The most recent observation is available, independent of the length of the oracle array, by passing 0 to observe()
              library Oracle {
                  struct Observation {
                      // the block timestamp of the observation
                      uint32 blockTimestamp;
                      // the tick accumulator, i.e. tick * time elapsed since the pool was first initialized
                      int56 tickCumulative;
                      // the seconds per liquidity, i.e. seconds elapsed / max(1, liquidity) since the pool was first initialized
                      uint160 secondsPerLiquidityCumulativeX128;
                      // whether or not the observation is initialized
                      bool initialized;
                  }
                  /// @notice Transforms a previous observation into a new observation, given the passage of time and the current tick and liquidity values
                  /// @dev blockTimestamp _must_ be chronologically equal to or greater than last.blockTimestamp, safe for 0 or 1 overflows
                  /// @param last The specified observation to be transformed
                  /// @param blockTimestamp The timestamp of the new observation
                  /// @param tick The active tick at the time of the new observation
                  /// @param liquidity The total in-range liquidity at the time of the new observation
                  /// @return Observation The newly populated observation
                  function transform(
                      Observation memory last,
                      uint32 blockTimestamp,
                      int24 tick,
                      uint128 liquidity
                  ) private pure returns (Observation memory) {
                      uint32 delta = blockTimestamp - last.blockTimestamp;
                      return
                          Observation({
                              blockTimestamp: blockTimestamp,
                              tickCumulative: last.tickCumulative + int56(tick) * delta,
                              secondsPerLiquidityCumulativeX128: last.secondsPerLiquidityCumulativeX128 +
                                  ((uint160(delta) << 128) / (liquidity > 0 ? liquidity : 1)),
                              initialized: true
                          });
                  }
                  /// @notice Initialize the oracle array by writing the first slot. Called once for the lifecycle of the observations array
                  /// @param self The stored oracle array
                  /// @param time The time of the oracle initialization, via block.timestamp truncated to uint32
                  /// @return cardinality The number of populated elements in the oracle array
                  /// @return cardinalityNext The new length of the oracle array, independent of population
                  function initialize(Observation[65535] storage self, uint32 time)
                      internal
                      returns (uint16 cardinality, uint16 cardinalityNext)
                  {
                      self[0] = Observation({
                          blockTimestamp: time,
                          tickCumulative: 0,
                          secondsPerLiquidityCumulativeX128: 0,
                          initialized: true
                      });
                      return (1, 1);
                  }
                  /// @notice Writes an oracle observation to the array
                  /// @dev Writable at most once per block. Index represents the most recently written element. cardinality and index must be tracked externally.
                  /// If the index is at the end of the allowable array length (according to cardinality), and the next cardinality
                  /// is greater than the current one, cardinality may be increased. This restriction is created to preserve ordering.
                  /// @param self The stored oracle array
                  /// @param index The index of the observation that was most recently written to the observations array
                  /// @param blockTimestamp The timestamp of the new observation
                  /// @param tick The active tick at the time of the new observation
                  /// @param liquidity The total in-range liquidity at the time of the new observation
                  /// @param cardinality The number of populated elements in the oracle array
                  /// @param cardinalityNext The new length of the oracle array, independent of population
                  /// @return indexUpdated The new index of the most recently written element in the oracle array
                  /// @return cardinalityUpdated The new cardinality of the oracle array
                  function write(
                      Observation[65535] storage self,
                      uint16 index,
                      uint32 blockTimestamp,
                      int24 tick,
                      uint128 liquidity,
                      uint16 cardinality,
                      uint16 cardinalityNext
                  ) internal returns (uint16 indexUpdated, uint16 cardinalityUpdated) {
                      Observation memory last = self[index];
                      // early return if we've already written an observation this block
                      if (last.blockTimestamp == blockTimestamp) return (index, cardinality);
                      // if the conditions are right, we can bump the cardinality
                      if (cardinalityNext > cardinality && index == (cardinality - 1)) {
                          cardinalityUpdated = cardinalityNext;
                      } else {
                          cardinalityUpdated = cardinality;
                      }
                      indexUpdated = (index + 1) % cardinalityUpdated;
                      self[indexUpdated] = transform(last, blockTimestamp, tick, liquidity);
                  }
                  /// @notice Prepares the oracle array to store up to `next` observations
                  /// @param self The stored oracle array
                  /// @param current The current next cardinality of the oracle array
                  /// @param next The proposed next cardinality which will be populated in the oracle array
                  /// @return next The next cardinality which will be populated in the oracle array
                  function grow(
                      Observation[65535] storage self,
                      uint16 current,
                      uint16 next
                  ) internal returns (uint16) {
                      require(current > 0, 'I');
                      // no-op if the passed next value isn't greater than the current next value
                      if (next <= current) return current;
                      // store in each slot to prevent fresh SSTOREs in swaps
                      // this data will not be used because the initialized boolean is still false
                      for (uint16 i = current; i < next; i++) self[i].blockTimestamp = 1;
                      return next;
                  }
                  /// @notice comparator for 32-bit timestamps
                  /// @dev safe for 0 or 1 overflows, a and b _must_ be chronologically before or equal to time
                  /// @param time A timestamp truncated to 32 bits
                  /// @param a A comparison timestamp from which to determine the relative position of `time`
                  /// @param b From which to determine the relative position of `time`
                  /// @return bool Whether `a` is chronologically <= `b`
                  function lte(
                      uint32 time,
                      uint32 a,
                      uint32 b
                  ) private pure returns (bool) {
                      // if there hasn't been overflow, no need to adjust
                      if (a <= time && b <= time) return a <= b;
                      uint256 aAdjusted = a > time ? a : a + 2**32;
                      uint256 bAdjusted = b > time ? b : b + 2**32;
                      return aAdjusted <= bAdjusted;
                  }
                  /// @notice Fetches the observations beforeOrAt and atOrAfter a target, i.e. where [beforeOrAt, atOrAfter] is satisfied.
                  /// The result may be the same observation, or adjacent observations.
                  /// @dev The answer must be contained in the array, used when the target is located within the stored observation
                  /// boundaries: older than the most recent observation and younger, or the same age as, the oldest observation
                  /// @param self The stored oracle array
                  /// @param time The current block.timestamp
                  /// @param target The timestamp at which the reserved observation should be for
                  /// @param index The index of the observation that was most recently written to the observations array
                  /// @param cardinality The number of populated elements in the oracle array
                  /// @return beforeOrAt The observation recorded before, or at, the target
                  /// @return atOrAfter The observation recorded at, or after, the target
                  function binarySearch(
                      Observation[65535] storage self,
                      uint32 time,
                      uint32 target,
                      uint16 index,
                      uint16 cardinality
                  ) private view returns (Observation memory beforeOrAt, Observation memory atOrAfter) {
                      uint256 l = (index + 1) % cardinality; // oldest observation
                      uint256 r = l + cardinality - 1; // newest observation
                      uint256 i;
                      while (true) {
                          i = (l + r) / 2;
                          beforeOrAt = self[i % cardinality];
                          // we've landed on an uninitialized tick, keep searching higher (more recently)
                          if (!beforeOrAt.initialized) {
                              l = i + 1;
                              continue;
                          }
                          atOrAfter = self[(i + 1) % cardinality];
                          bool targetAtOrAfter = lte(time, beforeOrAt.blockTimestamp, target);
                          // check if we've found the answer!
                          if (targetAtOrAfter && lte(time, target, atOrAfter.blockTimestamp)) break;
                          if (!targetAtOrAfter) r = i - 1;
                          else l = i + 1;
                      }
                  }
                  /// @notice Fetches the observations beforeOrAt and atOrAfter a given target, i.e. where [beforeOrAt, atOrAfter] is satisfied
                  /// @dev Assumes there is at least 1 initialized observation.
                  /// Used by observeSingle() to compute the counterfactual accumulator values as of a given block timestamp.
                  /// @param self The stored oracle array
                  /// @param time The current block.timestamp
                  /// @param target The timestamp at which the reserved observation should be for
                  /// @param tick The active tick at the time of the returned or simulated observation
                  /// @param index The index of the observation that was most recently written to the observations array
                  /// @param liquidity The total pool liquidity at the time of the call
                  /// @param cardinality The number of populated elements in the oracle array
                  /// @return beforeOrAt The observation which occurred at, or before, the given timestamp
                  /// @return atOrAfter The observation which occurred at, or after, the given timestamp
                  function getSurroundingObservations(
                      Observation[65535] storage self,
                      uint32 time,
                      uint32 target,
                      int24 tick,
                      uint16 index,
                      uint128 liquidity,
                      uint16 cardinality
                  ) private view returns (Observation memory beforeOrAt, Observation memory atOrAfter) {
                      // optimistically set before to the newest observation
                      beforeOrAt = self[index];
                      // if the target is chronologically at or after the newest observation, we can early return
                      if (lte(time, beforeOrAt.blockTimestamp, target)) {
                          if (beforeOrAt.blockTimestamp == target) {
                              // if newest observation equals target, we're in the same block, so we can ignore atOrAfter
                              return (beforeOrAt, atOrAfter);
                          } else {
                              // otherwise, we need to transform
                              return (beforeOrAt, transform(beforeOrAt, target, tick, liquidity));
                          }
                      }
                      // now, set before to the oldest observation
                      beforeOrAt = self[(index + 1) % cardinality];
                      if (!beforeOrAt.initialized) beforeOrAt = self[0];
                      // ensure that the target is chronologically at or after the oldest observation
                      require(lte(time, beforeOrAt.blockTimestamp, target), 'OLD');
                      // if we've reached this point, we have to binary search
                      return binarySearch(self, time, target, index, cardinality);
                  }
                  /// @dev Reverts if an observation at or before the desired observation timestamp does not exist.
                  /// 0 may be passed as `secondsAgo' to return the current cumulative values.
                  /// If called with a timestamp falling between two observations, returns the counterfactual accumulator values
                  /// at exactly the timestamp between the two observations.
                  /// @param self The stored oracle array
                  /// @param time The current block timestamp
                  /// @param secondsAgo The amount of time to look back, in seconds, at which point to return an observation
                  /// @param tick The current tick
                  /// @param index The index of the observation that was most recently written to the observations array
                  /// @param liquidity The current in-range pool liquidity
                  /// @param cardinality The number of populated elements in the oracle array
                  /// @return tickCumulative The tick * time elapsed since the pool was first initialized, as of `secondsAgo`
                  /// @return secondsPerLiquidityCumulativeX128 The time elapsed / max(1, liquidity) since the pool was first initialized, as of `secondsAgo`
                  function observeSingle(
                      Observation[65535] storage self,
                      uint32 time,
                      uint32 secondsAgo,
                      int24 tick,
                      uint16 index,
                      uint128 liquidity,
                      uint16 cardinality
                  ) internal view returns (int56 tickCumulative, uint160 secondsPerLiquidityCumulativeX128) {
                      if (secondsAgo == 0) {
                          Observation memory last = self[index];
                          if (last.blockTimestamp != time) last = transform(last, time, tick, liquidity);
                          return (last.tickCumulative, last.secondsPerLiquidityCumulativeX128);
                      }
                      uint32 target = time - secondsAgo;
                      (Observation memory beforeOrAt, Observation memory atOrAfter) =
                          getSurroundingObservations(self, time, target, tick, index, liquidity, cardinality);
                      if (target == beforeOrAt.blockTimestamp) {
                          // we're at the left boundary
                          return (beforeOrAt.tickCumulative, beforeOrAt.secondsPerLiquidityCumulativeX128);
                      } else if (target == atOrAfter.blockTimestamp) {
                          // we're at the right boundary
                          return (atOrAfter.tickCumulative, atOrAfter.secondsPerLiquidityCumulativeX128);
                      } else {
                          // we're in the middle
                          uint32 observationTimeDelta = atOrAfter.blockTimestamp - beforeOrAt.blockTimestamp;
                          uint32 targetDelta = target - beforeOrAt.blockTimestamp;
                          return (
                              beforeOrAt.tickCumulative +
                                  ((atOrAfter.tickCumulative - beforeOrAt.tickCumulative) / observationTimeDelta) *
                                  targetDelta,
                              beforeOrAt.secondsPerLiquidityCumulativeX128 +
                                  uint160(
                                      (uint256(
                                          atOrAfter.secondsPerLiquidityCumulativeX128 - beforeOrAt.secondsPerLiquidityCumulativeX128
                                      ) * targetDelta) / observationTimeDelta
                                  )
                          );
                      }
                  }
                  /// @notice Returns the accumulator values as of each time seconds ago from the given time in the array of `secondsAgos`
                  /// @dev Reverts if `secondsAgos` > oldest observation
                  /// @param self The stored oracle array
                  /// @param time The current block.timestamp
                  /// @param secondsAgos Each amount of time to look back, in seconds, at which point to return an observation
                  /// @param tick The current tick
                  /// @param index The index of the observation that was most recently written to the observations array
                  /// @param liquidity The current in-range pool liquidity
                  /// @param cardinality The number of populated elements in the oracle array
                  /// @return tickCumulatives The tick * time elapsed since the pool was first initialized, as of each `secondsAgo`
                  /// @return secondsPerLiquidityCumulativeX128s The cumulative seconds / max(1, liquidity) since the pool was first initialized, as of each `secondsAgo`
                  function observe(
                      Observation[65535] storage self,
                      uint32 time,
                      uint32[] memory secondsAgos,
                      int24 tick,
                      uint16 index,
                      uint128 liquidity,
                      uint16 cardinality
                  ) internal view returns (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s) {
                      require(cardinality > 0, 'I');
                      tickCumulatives = new int56[](secondsAgos.length);
                      secondsPerLiquidityCumulativeX128s = new uint160[](secondsAgos.length);
                      for (uint256 i = 0; i < secondsAgos.length; i++) {
                          (tickCumulatives[i], secondsPerLiquidityCumulativeX128s[i]) = observeSingle(
                              self,
                              time,
                              secondsAgos[i],
                              tick,
                              index,
                              liquidity,
                              cardinality
                          );
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.4.0;
              /// @title Contains 512-bit math functions
              /// @notice Facilitates multiplication and division that can have overflow of an intermediate value without any loss of precision
              /// @dev Handles "phantom overflow" i.e., allows multiplication and division where an intermediate value overflows 256 bits
              library FullMath {
                  /// @notice Calculates floor(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
                  /// @param a The multiplicand
                  /// @param b The multiplier
                  /// @param denominator The divisor
                  /// @return result The 256-bit result
                  /// @dev Credit to Remco Bloemen under MIT license https://xn--2-umb.com/21/muldiv
                  function mulDiv(
                      uint256 a,
                      uint256 b,
                      uint256 denominator
                  ) internal pure returns (uint256 result) {
                      // 512-bit multiply [prod1 prod0] = a * b
                      // Compute the product mod 2**256 and mod 2**256 - 1
                      // then use the Chinese Remainder Theorem to reconstruct
                      // the 512 bit result. The result is stored in two 256
                      // variables such that product = prod1 * 2**256 + prod0
                      uint256 prod0; // Least significant 256 bits of the product
                      uint256 prod1; // Most significant 256 bits of the product
                      assembly {
                          let mm := mulmod(a, b, not(0))
                          prod0 := mul(a, b)
                          prod1 := sub(sub(mm, prod0), lt(mm, prod0))
                      }
                      // Handle non-overflow cases, 256 by 256 division
                      if (prod1 == 0) {
                          require(denominator > 0);
                          assembly {
                              result := div(prod0, denominator)
                          }
                          return result;
                      }
                      // Make sure the result is less than 2**256.
                      // Also prevents denominator == 0
                      require(denominator > prod1);
                      ///////////////////////////////////////////////
                      // 512 by 256 division.
                      ///////////////////////////////////////////////
                      // Make division exact by subtracting the remainder from [prod1 prod0]
                      // Compute remainder using mulmod
                      uint256 remainder;
                      assembly {
                          remainder := mulmod(a, b, denominator)
                      }
                      // Subtract 256 bit number from 512 bit number
                      assembly {
                          prod1 := sub(prod1, gt(remainder, prod0))
                          prod0 := sub(prod0, remainder)
                      }
                      // Factor powers of two out of denominator
                      // Compute largest power of two divisor of denominator.
                      // Always >= 1.
                      uint256 twos = -denominator & denominator;
                      // Divide denominator by power of two
                      assembly {
                          denominator := div(denominator, twos)
                      }
                      // Divide [prod1 prod0] by the factors of two
                      assembly {
                          prod0 := div(prod0, twos)
                      }
                      // Shift in bits from prod1 into prod0. For this we need
                      // to flip `twos` such that it is 2**256 / twos.
                      // If twos is zero, then it becomes one
                      assembly {
                          twos := add(div(sub(0, twos), twos), 1)
                      }
                      prod0 |= prod1 * twos;
                      // Invert denominator mod 2**256
                      // Now that denominator is an odd number, it has an inverse
                      // modulo 2**256 such that denominator * inv = 1 mod 2**256.
                      // Compute the inverse by starting with a seed that is correct
                      // correct for four bits. That is, denominator * inv = 1 mod 2**4
                      uint256 inv = (3 * denominator) ^ 2;
                      // Now use Newton-Raphson iteration to improve the precision.
                      // Thanks to Hensel's lifting lemma, this also works in modular
                      // arithmetic, doubling the correct bits in each step.
                      inv *= 2 - denominator * inv; // inverse mod 2**8
                      inv *= 2 - denominator * inv; // inverse mod 2**16
                      inv *= 2 - denominator * inv; // inverse mod 2**32
                      inv *= 2 - denominator * inv; // inverse mod 2**64
                      inv *= 2 - denominator * inv; // inverse mod 2**128
                      inv *= 2 - denominator * inv; // inverse mod 2**256
                      // Because the division is now exact we can divide by multiplying
                      // with the modular inverse of denominator. This will give us the
                      // correct result modulo 2**256. Since the precoditions guarantee
                      // that the outcome is less than 2**256, this is the final result.
                      // We don't need to compute the high bits of the result and prod1
                      // is no longer required.
                      result = prod0 * inv;
                      return result;
                  }
                  /// @notice Calculates ceil(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
                  /// @param a The multiplicand
                  /// @param b The multiplier
                  /// @param denominator The divisor
                  /// @return result The 256-bit result
                  function mulDivRoundingUp(
                      uint256 a,
                      uint256 b,
                      uint256 denominator
                  ) internal pure returns (uint256 result) {
                      result = mulDiv(a, b, denominator);
                      if (mulmod(a, b, denominator) > 0) {
                          require(result < type(uint256).max);
                          result++;
                      }
                  }
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.4.0;
              /// @title FixedPoint128
              /// @notice A library for handling binary fixed point numbers, see https://en.wikipedia.org/wiki/Q_(number_format)
              library FixedPoint128 {
                  uint256 internal constant Q128 = 0x100000000000000000000000000000000;
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.6.0;
              import '../interfaces/IERC20Minimal.sol';
              /// @title TransferHelper
              /// @notice Contains helper methods for interacting with ERC20 tokens that do not consistently return true/false
              library TransferHelper {
                  /// @notice Transfers tokens from msg.sender to a recipient
                  /// @dev Calls transfer on token contract, errors with TF if transfer fails
                  /// @param token The contract address of the token which will be transferred
                  /// @param to The recipient of the transfer
                  /// @param value The value of the transfer
                  function safeTransfer(
                      address token,
                      address to,
                      uint256 value
                  ) internal {
                      (bool success, bytes memory data) =
                          token.call(abi.encodeWithSelector(IERC20Minimal.transfer.selector, to, value));
                      require(success && (data.length == 0 || abi.decode(data, (bool))), 'TF');
                  }
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Math library for computing sqrt prices from ticks and vice versa
              /// @notice Computes sqrt price for ticks of size 1.0001, i.e. sqrt(1.0001^tick) as fixed point Q64.96 numbers. Supports
              /// prices between 2**-128 and 2**128
              library TickMath {
                  /// @dev The minimum tick that may be passed to #getSqrtRatioAtTick computed from log base 1.0001 of 2**-128
                  int24 internal constant MIN_TICK = -887272;
                  /// @dev The maximum tick that may be passed to #getSqrtRatioAtTick computed from log base 1.0001 of 2**128
                  int24 internal constant MAX_TICK = -MIN_TICK;
                  /// @dev The minimum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MIN_TICK)
                  uint160 internal constant MIN_SQRT_RATIO = 4295128739;
                  /// @dev The maximum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MAX_TICK)
                  uint160 internal constant MAX_SQRT_RATIO = 1461446703485210103287273052203988822378723970342;
                  /// @notice Calculates sqrt(1.0001^tick) * 2^96
                  /// @dev Throws if |tick| > max tick
                  /// @param tick The input tick for the above formula
                  /// @return sqrtPriceX96 A Fixed point Q64.96 number representing the sqrt of the ratio of the two assets (token1/token0)
                  /// at the given tick
                  function getSqrtRatioAtTick(int24 tick) internal pure returns (uint160 sqrtPriceX96) {
                      uint256 absTick = tick < 0 ? uint256(-int256(tick)) : uint256(int256(tick));
                      require(absTick <= uint256(MAX_TICK), 'T');
                      uint256 ratio = absTick & 0x1 != 0 ? 0xfffcb933bd6fad37aa2d162d1a594001 : 0x100000000000000000000000000000000;
                      if (absTick & 0x2 != 0) ratio = (ratio * 0xfff97272373d413259a46990580e213a) >> 128;
                      if (absTick & 0x4 != 0) ratio = (ratio * 0xfff2e50f5f656932ef12357cf3c7fdcc) >> 128;
                      if (absTick & 0x8 != 0) ratio = (ratio * 0xffe5caca7e10e4e61c3624eaa0941cd0) >> 128;
                      if (absTick & 0x10 != 0) ratio = (ratio * 0xffcb9843d60f6159c9db58835c926644) >> 128;
                      if (absTick & 0x20 != 0) ratio = (ratio * 0xff973b41fa98c081472e6896dfb254c0) >> 128;
                      if (absTick & 0x40 != 0) ratio = (ratio * 0xff2ea16466c96a3843ec78b326b52861) >> 128;
                      if (absTick & 0x80 != 0) ratio = (ratio * 0xfe5dee046a99a2a811c461f1969c3053) >> 128;
                      if (absTick & 0x100 != 0) ratio = (ratio * 0xfcbe86c7900a88aedcffc83b479aa3a4) >> 128;
                      if (absTick & 0x200 != 0) ratio = (ratio * 0xf987a7253ac413176f2b074cf7815e54) >> 128;
                      if (absTick & 0x400 != 0) ratio = (ratio * 0xf3392b0822b70005940c7a398e4b70f3) >> 128;
                      if (absTick & 0x800 != 0) ratio = (ratio * 0xe7159475a2c29b7443b29c7fa6e889d9) >> 128;
                      if (absTick & 0x1000 != 0) ratio = (ratio * 0xd097f3bdfd2022b8845ad8f792aa5825) >> 128;
                      if (absTick & 0x2000 != 0) ratio = (ratio * 0xa9f746462d870fdf8a65dc1f90e061e5) >> 128;
                      if (absTick & 0x4000 != 0) ratio = (ratio * 0x70d869a156d2a1b890bb3df62baf32f7) >> 128;
                      if (absTick & 0x8000 != 0) ratio = (ratio * 0x31be135f97d08fd981231505542fcfa6) >> 128;
                      if (absTick & 0x10000 != 0) ratio = (ratio * 0x9aa508b5b7a84e1c677de54f3e99bc9) >> 128;
                      if (absTick & 0x20000 != 0) ratio = (ratio * 0x5d6af8dedb81196699c329225ee604) >> 128;
                      if (absTick & 0x40000 != 0) ratio = (ratio * 0x2216e584f5fa1ea926041bedfe98) >> 128;
                      if (absTick & 0x80000 != 0) ratio = (ratio * 0x48a170391f7dc42444e8fa2) >> 128;
                      if (tick > 0) ratio = type(uint256).max / ratio;
                      // this divides by 1<<32 rounding up to go from a Q128.128 to a Q128.96.
                      // we then downcast because we know the result always fits within 160 bits due to our tick input constraint
                      // we round up in the division so getTickAtSqrtRatio of the output price is always consistent
                      sqrtPriceX96 = uint160((ratio >> 32) + (ratio % (1 << 32) == 0 ? 0 : 1));
                  }
                  /// @notice Calculates the greatest tick value such that getRatioAtTick(tick) <= ratio
                  /// @dev Throws in case sqrtPriceX96 < MIN_SQRT_RATIO, as MIN_SQRT_RATIO is the lowest value getRatioAtTick may
                  /// ever return.
                  /// @param sqrtPriceX96 The sqrt ratio for which to compute the tick as a Q64.96
                  /// @return tick The greatest tick for which the ratio is less than or equal to the input ratio
                  function getTickAtSqrtRatio(uint160 sqrtPriceX96) internal pure returns (int24 tick) {
                      // second inequality must be < because the price can never reach the price at the max tick
                      require(sqrtPriceX96 >= MIN_SQRT_RATIO && sqrtPriceX96 < MAX_SQRT_RATIO, 'R');
                      uint256 ratio = uint256(sqrtPriceX96) << 32;
                      uint256 r = ratio;
                      uint256 msb = 0;
                      assembly {
                          let f := shl(7, gt(r, 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF))
                          msb := or(msb, f)
                          r := shr(f, r)
                      }
                      assembly {
                          let f := shl(6, gt(r, 0xFFFFFFFFFFFFFFFF))
                          msb := or(msb, f)
                          r := shr(f, r)
                      }
                      assembly {
                          let f := shl(5, gt(r, 0xFFFFFFFF))
                          msb := or(msb, f)
                          r := shr(f, r)
                      }
                      assembly {
                          let f := shl(4, gt(r, 0xFFFF))
                          msb := or(msb, f)
                          r := shr(f, r)
                      }
                      assembly {
                          let f := shl(3, gt(r, 0xFF))
                          msb := or(msb, f)
                          r := shr(f, r)
                      }
                      assembly {
                          let f := shl(2, gt(r, 0xF))
                          msb := or(msb, f)
                          r := shr(f, r)
                      }
                      assembly {
                          let f := shl(1, gt(r, 0x3))
                          msb := or(msb, f)
                          r := shr(f, r)
                      }
                      assembly {
                          let f := gt(r, 0x1)
                          msb := or(msb, f)
                      }
                      if (msb >= 128) r = ratio >> (msb - 127);
                      else r = ratio << (127 - msb);
                      int256 log_2 = (int256(msb) - 128) << 64;
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(63, f))
                          r := shr(f, r)
                      }
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(62, f))
                          r := shr(f, r)
                      }
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(61, f))
                          r := shr(f, r)
                      }
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(60, f))
                          r := shr(f, r)
                      }
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(59, f))
                          r := shr(f, r)
                      }
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(58, f))
                          r := shr(f, r)
                      }
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(57, f))
                          r := shr(f, r)
                      }
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(56, f))
                          r := shr(f, r)
                      }
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(55, f))
                          r := shr(f, r)
                      }
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(54, f))
                          r := shr(f, r)
                      }
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(53, f))
                          r := shr(f, r)
                      }
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(52, f))
                          r := shr(f, r)
                      }
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(51, f))
                          r := shr(f, r)
                      }
                      assembly {
                          r := shr(127, mul(r, r))
                          let f := shr(128, r)
                          log_2 := or(log_2, shl(50, f))
                      }
                      int256 log_sqrt10001 = log_2 * 255738958999603826347141; // 128.128 number
                      int24 tickLow = int24((log_sqrt10001 - 3402992956809132418596140100660247210) >> 128);
                      int24 tickHi = int24((log_sqrt10001 + 291339464771989622907027621153398088495) >> 128);
                      tick = tickLow == tickHi ? tickLow : getSqrtRatioAtTick(tickHi) <= sqrtPriceX96 ? tickHi : tickLow;
                  }
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Math library for liquidity
              library LiquidityMath {
                  /// @notice Add a signed liquidity delta to liquidity and revert if it overflows or underflows
                  /// @param x The liquidity before change
                  /// @param y The delta by which liquidity should be changed
                  /// @return z The liquidity delta
                  function addDelta(uint128 x, int128 y) internal pure returns (uint128 z) {
                      if (y < 0) {
                          require((z = x - uint128(-y)) < x, 'LS');
                      } else {
                          require((z = x + uint128(y)) >= x, 'LA');
                      }
                  }
              }
              // SPDX-License-Identifier: BUSL-1.1
              pragma solidity >=0.5.0;
              import './LowGasSafeMath.sol';
              import './SafeCast.sol';
              import './FullMath.sol';
              import './UnsafeMath.sol';
              import './FixedPoint96.sol';
              /// @title Functions based on Q64.96 sqrt price and liquidity
              /// @notice Contains the math that uses square root of price as a Q64.96 and liquidity to compute deltas
              library SqrtPriceMath {
                  using LowGasSafeMath for uint256;
                  using SafeCast for uint256;
                  /// @notice Gets the next sqrt price given a delta of token0
                  /// @dev Always rounds up, because in the exact output case (increasing price) we need to move the price at least
                  /// far enough to get the desired output amount, and in the exact input case (decreasing price) we need to move the
                  /// price less in order to not send too much output.
                  /// The most precise formula for this is liquidity * sqrtPX96 / (liquidity +- amount * sqrtPX96),
                  /// if this is impossible because of overflow, we calculate liquidity / (liquidity / sqrtPX96 +- amount).
                  /// @param sqrtPX96 The starting price, i.e. before accounting for the token0 delta
                  /// @param liquidity The amount of usable liquidity
                  /// @param amount How much of token0 to add or remove from virtual reserves
                  /// @param add Whether to add or remove the amount of token0
                  /// @return The price after adding or removing amount, depending on add
                  function getNextSqrtPriceFromAmount0RoundingUp(
                      uint160 sqrtPX96,
                      uint128 liquidity,
                      uint256 amount,
                      bool add
                  ) internal pure returns (uint160) {
                      // we short circuit amount == 0 because the result is otherwise not guaranteed to equal the input price
                      if (amount == 0) return sqrtPX96;
                      uint256 numerator1 = uint256(liquidity) << FixedPoint96.RESOLUTION;
                      if (add) {
                          uint256 product;
                          if ((product = amount * sqrtPX96) / amount == sqrtPX96) {
                              uint256 denominator = numerator1 + product;
                              if (denominator >= numerator1)
                                  // always fits in 160 bits
                                  return uint160(FullMath.mulDivRoundingUp(numerator1, sqrtPX96, denominator));
                          }
                          return uint160(UnsafeMath.divRoundingUp(numerator1, (numerator1 / sqrtPX96).add(amount)));
                      } else {
                          uint256 product;
                          // if the product overflows, we know the denominator underflows
                          // in addition, we must check that the denominator does not underflow
                          require((product = amount * sqrtPX96) / amount == sqrtPX96 && numerator1 > product);
                          uint256 denominator = numerator1 - product;
                          return FullMath.mulDivRoundingUp(numerator1, sqrtPX96, denominator).toUint160();
                      }
                  }
                  /// @notice Gets the next sqrt price given a delta of token1
                  /// @dev Always rounds down, because in the exact output case (decreasing price) we need to move the price at least
                  /// far enough to get the desired output amount, and in the exact input case (increasing price) we need to move the
                  /// price less in order to not send too much output.
                  /// The formula we compute is within <1 wei of the lossless version: sqrtPX96 +- amount / liquidity
                  /// @param sqrtPX96 The starting price, i.e., before accounting for the token1 delta
                  /// @param liquidity The amount of usable liquidity
                  /// @param amount How much of token1 to add, or remove, from virtual reserves
                  /// @param add Whether to add, or remove, the amount of token1
                  /// @return The price after adding or removing `amount`
                  function getNextSqrtPriceFromAmount1RoundingDown(
                      uint160 sqrtPX96,
                      uint128 liquidity,
                      uint256 amount,
                      bool add
                  ) internal pure returns (uint160) {
                      // if we're adding (subtracting), rounding down requires rounding the quotient down (up)
                      // in both cases, avoid a mulDiv for most inputs
                      if (add) {
                          uint256 quotient =
                              (
                                  amount <= type(uint160).max
                                      ? (amount << FixedPoint96.RESOLUTION) / liquidity
                                      : FullMath.mulDiv(amount, FixedPoint96.Q96, liquidity)
                              );
                          return uint256(sqrtPX96).add(quotient).toUint160();
                      } else {
                          uint256 quotient =
                              (
                                  amount <= type(uint160).max
                                      ? UnsafeMath.divRoundingUp(amount << FixedPoint96.RESOLUTION, liquidity)
                                      : FullMath.mulDivRoundingUp(amount, FixedPoint96.Q96, liquidity)
                              );
                          require(sqrtPX96 > quotient);
                          // always fits 160 bits
                          return uint160(sqrtPX96 - quotient);
                      }
                  }
                  /// @notice Gets the next sqrt price given an input amount of token0 or token1
                  /// @dev Throws if price or liquidity are 0, or if the next price is out of bounds
                  /// @param sqrtPX96 The starting price, i.e., before accounting for the input amount
                  /// @param liquidity The amount of usable liquidity
                  /// @param amountIn How much of token0, or token1, is being swapped in
                  /// @param zeroForOne Whether the amount in is token0 or token1
                  /// @return sqrtQX96 The price after adding the input amount to token0 or token1
                  function getNextSqrtPriceFromInput(
                      uint160 sqrtPX96,
                      uint128 liquidity,
                      uint256 amountIn,
                      bool zeroForOne
                  ) internal pure returns (uint160 sqrtQX96) {
                      require(sqrtPX96 > 0);
                      require(liquidity > 0);
                      // round to make sure that we don't pass the target price
                      return
                          zeroForOne
                              ? getNextSqrtPriceFromAmount0RoundingUp(sqrtPX96, liquidity, amountIn, true)
                              : getNextSqrtPriceFromAmount1RoundingDown(sqrtPX96, liquidity, amountIn, true);
                  }
                  /// @notice Gets the next sqrt price given an output amount of token0 or token1
                  /// @dev Throws if price or liquidity are 0 or the next price is out of bounds
                  /// @param sqrtPX96 The starting price before accounting for the output amount
                  /// @param liquidity The amount of usable liquidity
                  /// @param amountOut How much of token0, or token1, is being swapped out
                  /// @param zeroForOne Whether the amount out is token0 or token1
                  /// @return sqrtQX96 The price after removing the output amount of token0 or token1
                  function getNextSqrtPriceFromOutput(
                      uint160 sqrtPX96,
                      uint128 liquidity,
                      uint256 amountOut,
                      bool zeroForOne
                  ) internal pure returns (uint160 sqrtQX96) {
                      require(sqrtPX96 > 0);
                      require(liquidity > 0);
                      // round to make sure that we pass the target price
                      return
                          zeroForOne
                              ? getNextSqrtPriceFromAmount1RoundingDown(sqrtPX96, liquidity, amountOut, false)
                              : getNextSqrtPriceFromAmount0RoundingUp(sqrtPX96, liquidity, amountOut, false);
                  }
                  /// @notice Gets the amount0 delta between two prices
                  /// @dev Calculates liquidity / sqrt(lower) - liquidity / sqrt(upper),
                  /// i.e. liquidity * (sqrt(upper) - sqrt(lower)) / (sqrt(upper) * sqrt(lower))
                  /// @param sqrtRatioAX96 A sqrt price
                  /// @param sqrtRatioBX96 Another sqrt price
                  /// @param liquidity The amount of usable liquidity
                  /// @param roundUp Whether to round the amount up or down
                  /// @return amount0 Amount of token0 required to cover a position of size liquidity between the two passed prices
                  function getAmount0Delta(
                      uint160 sqrtRatioAX96,
                      uint160 sqrtRatioBX96,
                      uint128 liquidity,
                      bool roundUp
                  ) internal pure returns (uint256 amount0) {
                      if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);
                      uint256 numerator1 = uint256(liquidity) << FixedPoint96.RESOLUTION;
                      uint256 numerator2 = sqrtRatioBX96 - sqrtRatioAX96;
                      require(sqrtRatioAX96 > 0);
                      return
                          roundUp
                              ? UnsafeMath.divRoundingUp(
                                  FullMath.mulDivRoundingUp(numerator1, numerator2, sqrtRatioBX96),
                                  sqrtRatioAX96
                              )
                              : FullMath.mulDiv(numerator1, numerator2, sqrtRatioBX96) / sqrtRatioAX96;
                  }
                  /// @notice Gets the amount1 delta between two prices
                  /// @dev Calculates liquidity * (sqrt(upper) - sqrt(lower))
                  /// @param sqrtRatioAX96 A sqrt price
                  /// @param sqrtRatioBX96 Another sqrt price
                  /// @param liquidity The amount of usable liquidity
                  /// @param roundUp Whether to round the amount up, or down
                  /// @return amount1 Amount of token1 required to cover a position of size liquidity between the two passed prices
                  function getAmount1Delta(
                      uint160 sqrtRatioAX96,
                      uint160 sqrtRatioBX96,
                      uint128 liquidity,
                      bool roundUp
                  ) internal pure returns (uint256 amount1) {
                      if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);
                      return
                          roundUp
                              ? FullMath.mulDivRoundingUp(liquidity, sqrtRatioBX96 - sqrtRatioAX96, FixedPoint96.Q96)
                              : FullMath.mulDiv(liquidity, sqrtRatioBX96 - sqrtRatioAX96, FixedPoint96.Q96);
                  }
                  /// @notice Helper that gets signed token0 delta
                  /// @param sqrtRatioAX96 A sqrt price
                  /// @param sqrtRatioBX96 Another sqrt price
                  /// @param liquidity The change in liquidity for which to compute the amount0 delta
                  /// @return amount0 Amount of token0 corresponding to the passed liquidityDelta between the two prices
                  function getAmount0Delta(
                      uint160 sqrtRatioAX96,
                      uint160 sqrtRatioBX96,
                      int128 liquidity
                  ) internal pure returns (int256 amount0) {
                      return
                          liquidity < 0
                              ? -getAmount0Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(-liquidity), false).toInt256()
                              : getAmount0Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(liquidity), true).toInt256();
                  }
                  /// @notice Helper that gets signed token1 delta
                  /// @param sqrtRatioAX96 A sqrt price
                  /// @param sqrtRatioBX96 Another sqrt price
                  /// @param liquidity The change in liquidity for which to compute the amount1 delta
                  /// @return amount1 Amount of token1 corresponding to the passed liquidityDelta between the two prices
                  function getAmount1Delta(
                      uint160 sqrtRatioAX96,
                      uint160 sqrtRatioBX96,
                      int128 liquidity
                  ) internal pure returns (int256 amount1) {
                      return
                          liquidity < 0
                              ? -getAmount1Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(-liquidity), false).toInt256()
                              : getAmount1Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(liquidity), true).toInt256();
                  }
              }
              // SPDX-License-Identifier: BUSL-1.1
              pragma solidity >=0.5.0;
              import './FullMath.sol';
              import './SqrtPriceMath.sol';
              /// @title Computes the result of a swap within ticks
              /// @notice Contains methods for computing the result of a swap within a single tick price range, i.e., a single tick.
              library SwapMath {
                  /// @notice Computes the result of swapping some amount in, or amount out, given the parameters of the swap
                  /// @dev The fee, plus the amount in, will never exceed the amount remaining if the swap's `amountSpecified` is positive
                  /// @param sqrtRatioCurrentX96 The current sqrt price of the pool
                  /// @param sqrtRatioTargetX96 The price that cannot be exceeded, from which the direction of the swap is inferred
                  /// @param liquidity The usable liquidity
                  /// @param amountRemaining How much input or output amount is remaining to be swapped in/out
                  /// @param feePips The fee taken from the input amount, expressed in hundredths of a bip
                  /// @return sqrtRatioNextX96 The price after swapping the amount in/out, not to exceed the price target
                  /// @return amountIn The amount to be swapped in, of either token0 or token1, based on the direction of the swap
                  /// @return amountOut The amount to be received, of either token0 or token1, based on the direction of the swap
                  /// @return feeAmount The amount of input that will be taken as a fee
                  function computeSwapStep(
                      uint160 sqrtRatioCurrentX96,
                      uint160 sqrtRatioTargetX96,
                      uint128 liquidity,
                      int256 amountRemaining,
                      uint24 feePips
                  )
                      internal
                      pure
                      returns (
                          uint160 sqrtRatioNextX96,
                          uint256 amountIn,
                          uint256 amountOut,
                          uint256 feeAmount
                      )
                  {
                      bool zeroForOne = sqrtRatioCurrentX96 >= sqrtRatioTargetX96;
                      bool exactIn = amountRemaining >= 0;
                      if (exactIn) {
                          uint256 amountRemainingLessFee = FullMath.mulDiv(uint256(amountRemaining), 1e6 - feePips, 1e6);
                          amountIn = zeroForOne
                              ? SqrtPriceMath.getAmount0Delta(sqrtRatioTargetX96, sqrtRatioCurrentX96, liquidity, true)
                              : SqrtPriceMath.getAmount1Delta(sqrtRatioCurrentX96, sqrtRatioTargetX96, liquidity, true);
                          if (amountRemainingLessFee >= amountIn) sqrtRatioNextX96 = sqrtRatioTargetX96;
                          else
                              sqrtRatioNextX96 = SqrtPriceMath.getNextSqrtPriceFromInput(
                                  sqrtRatioCurrentX96,
                                  liquidity,
                                  amountRemainingLessFee,
                                  zeroForOne
                              );
                      } else {
                          amountOut = zeroForOne
                              ? SqrtPriceMath.getAmount1Delta(sqrtRatioTargetX96, sqrtRatioCurrentX96, liquidity, false)
                              : SqrtPriceMath.getAmount0Delta(sqrtRatioCurrentX96, sqrtRatioTargetX96, liquidity, false);
                          if (uint256(-amountRemaining) >= amountOut) sqrtRatioNextX96 = sqrtRatioTargetX96;
                          else
                              sqrtRatioNextX96 = SqrtPriceMath.getNextSqrtPriceFromOutput(
                                  sqrtRatioCurrentX96,
                                  liquidity,
                                  uint256(-amountRemaining),
                                  zeroForOne
                              );
                      }
                      bool max = sqrtRatioTargetX96 == sqrtRatioNextX96;
                      // get the input/output amounts
                      if (zeroForOne) {
                          amountIn = max && exactIn
                              ? amountIn
                              : SqrtPriceMath.getAmount0Delta(sqrtRatioNextX96, sqrtRatioCurrentX96, liquidity, true);
                          amountOut = max && !exactIn
                              ? amountOut
                              : SqrtPriceMath.getAmount1Delta(sqrtRatioNextX96, sqrtRatioCurrentX96, liquidity, false);
                      } else {
                          amountIn = max && exactIn
                              ? amountIn
                              : SqrtPriceMath.getAmount1Delta(sqrtRatioCurrentX96, sqrtRatioNextX96, liquidity, true);
                          amountOut = max && !exactIn
                              ? amountOut
                              : SqrtPriceMath.getAmount0Delta(sqrtRatioCurrentX96, sqrtRatioNextX96, liquidity, false);
                      }
                      // cap the output amount to not exceed the remaining output amount
                      if (!exactIn && amountOut > uint256(-amountRemaining)) {
                          amountOut = uint256(-amountRemaining);
                      }
                      if (exactIn && sqrtRatioNextX96 != sqrtRatioTargetX96) {
                          // we didn't reach the target, so take the remainder of the maximum input as fee
                          feeAmount = uint256(amountRemaining) - amountIn;
                      } else {
                          feeAmount = FullMath.mulDivRoundingUp(amountIn, feePips, 1e6 - feePips);
                      }
                  }
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title An interface for a contract that is capable of deploying Uniswap V3 Pools
              /// @notice A contract that constructs a pool must implement this to pass arguments to the pool
              /// @dev This is used to avoid having constructor arguments in the pool contract, which results in the init code hash
              /// of the pool being constant allowing the CREATE2 address of the pool to be cheaply computed on-chain
              interface IUniswapV3PoolDeployer {
                  /// @notice Get the parameters to be used in constructing the pool, set transiently during pool creation.
                  /// @dev Called by the pool constructor to fetch the parameters of the pool
                  /// Returns factory The factory address
                  /// Returns token0 The first token of the pool by address sort order
                  /// Returns token1 The second token of the pool by address sort order
                  /// Returns fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
                  /// Returns tickSpacing The minimum number of ticks between initialized ticks
                  function parameters()
                      external
                      view
                      returns (
                          address factory,
                          address token0,
                          address token1,
                          uint24 fee,
                          int24 tickSpacing
                      );
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title The interface for the Uniswap V3 Factory
              /// @notice The Uniswap V3 Factory facilitates creation of Uniswap V3 pools and control over the protocol fees
              interface IUniswapV3Factory {
                  /// @notice Emitted when the owner of the factory is changed
                  /// @param oldOwner The owner before the owner was changed
                  /// @param newOwner The owner after the owner was changed
                  event OwnerChanged(address indexed oldOwner, address indexed newOwner);
                  /// @notice Emitted when a pool is created
                  /// @param token0 The first token of the pool by address sort order
                  /// @param token1 The second token of the pool by address sort order
                  /// @param fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
                  /// @param tickSpacing The minimum number of ticks between initialized ticks
                  /// @param pool The address of the created pool
                  event PoolCreated(
                      address indexed token0,
                      address indexed token1,
                      uint24 indexed fee,
                      int24 tickSpacing,
                      address pool
                  );
                  /// @notice Emitted when a new fee amount is enabled for pool creation via the factory
                  /// @param fee The enabled fee, denominated in hundredths of a bip
                  /// @param tickSpacing The minimum number of ticks between initialized ticks for pools created with the given fee
                  event FeeAmountEnabled(uint24 indexed fee, int24 indexed tickSpacing);
                  /// @notice Returns the current owner of the factory
                  /// @dev Can be changed by the current owner via setOwner
                  /// @return The address of the factory owner
                  function owner() external view returns (address);
                  /// @notice Returns the tick spacing for a given fee amount, if enabled, or 0 if not enabled
                  /// @dev A fee amount can never be removed, so this value should be hard coded or cached in the calling context
                  /// @param fee The enabled fee, denominated in hundredths of a bip. Returns 0 in case of unenabled fee
                  /// @return The tick spacing
                  function feeAmountTickSpacing(uint24 fee) external view returns (int24);
                  /// @notice Returns the pool address for a given pair of tokens and a fee, or address 0 if it does not exist
                  /// @dev tokenA and tokenB may be passed in either token0/token1 or token1/token0 order
                  /// @param tokenA The contract address of either token0 or token1
                  /// @param tokenB The contract address of the other token
                  /// @param fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
                  /// @return pool The pool address
                  function getPool(
                      address tokenA,
                      address tokenB,
                      uint24 fee
                  ) external view returns (address pool);
                  /// @notice Creates a pool for the given two tokens and fee
                  /// @param tokenA One of the two tokens in the desired pool
                  /// @param tokenB The other of the two tokens in the desired pool
                  /// @param fee The desired fee for the pool
                  /// @dev tokenA and tokenB may be passed in either order: token0/token1 or token1/token0. tickSpacing is retrieved
                  /// from the fee. The call will revert if the pool already exists, the fee is invalid, or the token arguments
                  /// are invalid.
                  /// @return pool The address of the newly created pool
                  function createPool(
                      address tokenA,
                      address tokenB,
                      uint24 fee
                  ) external returns (address pool);
                  /// @notice Updates the owner of the factory
                  /// @dev Must be called by the current owner
                  /// @param _owner The new owner of the factory
                  function setOwner(address _owner) external;
                  /// @notice Enables a fee amount with the given tickSpacing
                  /// @dev Fee amounts may never be removed once enabled
                  /// @param fee The fee amount to enable, denominated in hundredths of a bip (i.e. 1e-6)
                  /// @param tickSpacing The spacing between ticks to be enforced for all pools created with the given fee amount
                  function enableFeeAmount(uint24 fee, int24 tickSpacing) external;
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Minimal ERC20 interface for Uniswap
              /// @notice Contains a subset of the full ERC20 interface that is used in Uniswap V3
              interface IERC20Minimal {
                  /// @notice Returns the balance of a token
                  /// @param account The account for which to look up the number of tokens it has, i.e. its balance
                  /// @return The number of tokens held by the account
                  function balanceOf(address account) external view returns (uint256);
                  /// @notice Transfers the amount of token from the `msg.sender` to the recipient
                  /// @param recipient The account that will receive the amount transferred
                  /// @param amount The number of tokens to send from the sender to the recipient
                  /// @return Returns true for a successful transfer, false for an unsuccessful transfer
                  function transfer(address recipient, uint256 amount) external returns (bool);
                  /// @notice Returns the current allowance given to a spender by an owner
                  /// @param owner The account of the token owner
                  /// @param spender The account of the token spender
                  /// @return The current allowance granted by `owner` to `spender`
                  function allowance(address owner, address spender) external view returns (uint256);
                  /// @notice Sets the allowance of a spender from the `msg.sender` to the value `amount`
                  /// @param spender The account which will be allowed to spend a given amount of the owners tokens
                  /// @param amount The amount of tokens allowed to be used by `spender`
                  /// @return Returns true for a successful approval, false for unsuccessful
                  function approve(address spender, uint256 amount) external returns (bool);
                  /// @notice Transfers `amount` tokens from `sender` to `recipient` up to the allowance given to the `msg.sender`
                  /// @param sender The account from which the transfer will be initiated
                  /// @param recipient The recipient of the transfer
                  /// @param amount The amount of the transfer
                  /// @return Returns true for a successful transfer, false for unsuccessful
                  function transferFrom(
                      address sender,
                      address recipient,
                      uint256 amount
                  ) external returns (bool);
                  /// @notice Event emitted when tokens are transferred from one address to another, either via `#transfer` or `#transferFrom`.
                  /// @param from The account from which the tokens were sent, i.e. the balance decreased
                  /// @param to The account to which the tokens were sent, i.e. the balance increased
                  /// @param value The amount of tokens that were transferred
                  event Transfer(address indexed from, address indexed to, uint256 value);
                  /// @notice Event emitted when the approval amount for the spender of a given owner's tokens changes.
                  /// @param owner The account that approved spending of its tokens
                  /// @param spender The account for which the spending allowance was modified
                  /// @param value The new allowance from the owner to the spender
                  event Approval(address indexed owner, address indexed spender, uint256 value);
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Callback for IUniswapV3PoolActions#mint
              /// @notice Any contract that calls IUniswapV3PoolActions#mint must implement this interface
              interface IUniswapV3MintCallback {
                  /// @notice Called to `msg.sender` after minting liquidity to a position from IUniswapV3Pool#mint.
                  /// @dev In the implementation you must pay the pool tokens owed for the minted liquidity.
                  /// The caller of this method must be checked to be a UniswapV3Pool deployed by the canonical UniswapV3Factory.
                  /// @param amount0Owed The amount of token0 due to the pool for the minted liquidity
                  /// @param amount1Owed The amount of token1 due to the pool for the minted liquidity
                  /// @param data Any data passed through by the caller via the IUniswapV3PoolActions#mint call
                  function uniswapV3MintCallback(
                      uint256 amount0Owed,
                      uint256 amount1Owed,
                      bytes calldata data
                  ) external;
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Callback for IUniswapV3PoolActions#swap
              /// @notice Any contract that calls IUniswapV3PoolActions#swap must implement this interface
              interface IUniswapV3SwapCallback {
                  /// @notice Called to `msg.sender` after executing a swap via IUniswapV3Pool#swap.
                  /// @dev In the implementation you must pay the pool tokens owed for the swap.
                  /// The caller of this method must be checked to be a UniswapV3Pool deployed by the canonical UniswapV3Factory.
                  /// amount0Delta and amount1Delta can both be 0 if no tokens were swapped.
                  /// @param amount0Delta The amount of token0 that was sent (negative) or must be received (positive) by the pool by
                  /// the end of the swap. If positive, the callback must send that amount of token0 to the pool.
                  /// @param amount1Delta The amount of token1 that was sent (negative) or must be received (positive) by the pool by
                  /// the end of the swap. If positive, the callback must send that amount of token1 to the pool.
                  /// @param data Any data passed through by the caller via the IUniswapV3PoolActions#swap call
                  function uniswapV3SwapCallback(
                      int256 amount0Delta,
                      int256 amount1Delta,
                      bytes calldata data
                  ) external;
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Callback for IUniswapV3PoolActions#flash
              /// @notice Any contract that calls IUniswapV3PoolActions#flash must implement this interface
              interface IUniswapV3FlashCallback {
                  /// @notice Called to `msg.sender` after transferring to the recipient from IUniswapV3Pool#flash.
                  /// @dev In the implementation you must repay the pool the tokens sent by flash plus the computed fee amounts.
                  /// The caller of this method must be checked to be a UniswapV3Pool deployed by the canonical UniswapV3Factory.
                  /// @param fee0 The fee amount in token0 due to the pool by the end of the flash
                  /// @param fee1 The fee amount in token1 due to the pool by the end of the flash
                  /// @param data Any data passed through by the caller via the IUniswapV3PoolActions#flash call
                  function uniswapV3FlashCallback(
                      uint256 fee0,
                      uint256 fee1,
                      bytes calldata data
                  ) external;
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Pool state that never changes
              /// @notice These parameters are fixed for a pool forever, i.e., the methods will always return the same values
              interface IUniswapV3PoolImmutables {
                  /// @notice The contract that deployed the pool, which must adhere to the IUniswapV3Factory interface
                  /// @return The contract address
                  function factory() external view returns (address);
                  /// @notice The first of the two tokens of the pool, sorted by address
                  /// @return The token contract address
                  function token0() external view returns (address);
                  /// @notice The second of the two tokens of the pool, sorted by address
                  /// @return The token contract address
                  function token1() external view returns (address);
                  /// @notice The pool's fee in hundredths of a bip, i.e. 1e-6
                  /// @return The fee
                  function fee() external view returns (uint24);
                  /// @notice The pool tick spacing
                  /// @dev Ticks can only be used at multiples of this value, minimum of 1 and always positive
                  /// e.g.: a tickSpacing of 3 means ticks can be initialized every 3rd tick, i.e., ..., -6, -3, 0, 3, 6, ...
                  /// This value is an int24 to avoid casting even though it is always positive.
                  /// @return The tick spacing
                  function tickSpacing() external view returns (int24);
                  /// @notice The maximum amount of position liquidity that can use any tick in the range
                  /// @dev This parameter is enforced per tick to prevent liquidity from overflowing a uint128 at any point, and
                  /// also prevents out-of-range liquidity from being used to prevent adding in-range liquidity to a pool
                  /// @return The max amount of liquidity per tick
                  function maxLiquidityPerTick() external view returns (uint128);
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Pool state that can change
              /// @notice These methods compose the pool's state, and can change with any frequency including multiple times
              /// per transaction
              interface IUniswapV3PoolState {
                  /// @notice The 0th storage slot in the pool stores many values, and is exposed as a single method to save gas
                  /// when accessed externally.
                  /// @return sqrtPriceX96 The current price of the pool as a sqrt(token1/token0) Q64.96 value
                  /// tick The current tick of the pool, i.e. according to the last tick transition that was run.
                  /// This value may not always be equal to SqrtTickMath.getTickAtSqrtRatio(sqrtPriceX96) if the price is on a tick
                  /// boundary.
                  /// observationIndex The index of the last oracle observation that was written,
                  /// observationCardinality The current maximum number of observations stored in the pool,
                  /// observationCardinalityNext The next maximum number of observations, to be updated when the observation.
                  /// feeProtocol The protocol fee for both tokens of the pool.
                  /// Encoded as two 4 bit values, where the protocol fee of token1 is shifted 4 bits and the protocol fee of token0
                  /// is the lower 4 bits. Used as the denominator of a fraction of the swap fee, e.g. 4 means 1/4th of the swap fee.
                  /// unlocked Whether the pool is currently locked to reentrancy
                  function slot0()
                      external
                      view
                      returns (
                          uint160 sqrtPriceX96,
                          int24 tick,
                          uint16 observationIndex,
                          uint16 observationCardinality,
                          uint16 observationCardinalityNext,
                          uint8 feeProtocol,
                          bool unlocked
                      );
                  /// @notice The fee growth as a Q128.128 fees of token0 collected per unit of liquidity for the entire life of the pool
                  /// @dev This value can overflow the uint256
                  function feeGrowthGlobal0X128() external view returns (uint256);
                  /// @notice The fee growth as a Q128.128 fees of token1 collected per unit of liquidity for the entire life of the pool
                  /// @dev This value can overflow the uint256
                  function feeGrowthGlobal1X128() external view returns (uint256);
                  /// @notice The amounts of token0 and token1 that are owed to the protocol
                  /// @dev Protocol fees will never exceed uint128 max in either token
                  function protocolFees() external view returns (uint128 token0, uint128 token1);
                  /// @notice The currently in range liquidity available to the pool
                  /// @dev This value has no relationship to the total liquidity across all ticks
                  function liquidity() external view returns (uint128);
                  /// @notice Look up information about a specific tick in the pool
                  /// @param tick The tick to look up
                  /// @return liquidityGross the total amount of position liquidity that uses the pool either as tick lower or
                  /// tick upper,
                  /// liquidityNet how much liquidity changes when the pool price crosses the tick,
                  /// feeGrowthOutside0X128 the fee growth on the other side of the tick from the current tick in token0,
                  /// feeGrowthOutside1X128 the fee growth on the other side of the tick from the current tick in token1,
                  /// tickCumulativeOutside the cumulative tick value on the other side of the tick from the current tick
                  /// secondsPerLiquidityOutsideX128 the seconds spent per liquidity on the other side of the tick from the current tick,
                  /// secondsOutside the seconds spent on the other side of the tick from the current tick,
                  /// initialized Set to true if the tick is initialized, i.e. liquidityGross is greater than 0, otherwise equal to false.
                  /// Outside values can only be used if the tick is initialized, i.e. if liquidityGross is greater than 0.
                  /// In addition, these values are only relative and must be used only in comparison to previous snapshots for
                  /// a specific position.
                  function ticks(int24 tick)
                      external
                      view
                      returns (
                          uint128 liquidityGross,
                          int128 liquidityNet,
                          uint256 feeGrowthOutside0X128,
                          uint256 feeGrowthOutside1X128,
                          int56 tickCumulativeOutside,
                          uint160 secondsPerLiquidityOutsideX128,
                          uint32 secondsOutside,
                          bool initialized
                      );
                  /// @notice Returns 256 packed tick initialized boolean values. See TickBitmap for more information
                  function tickBitmap(int16 wordPosition) external view returns (uint256);
                  /// @notice Returns the information about a position by the position's key
                  /// @param key The position's key is a hash of a preimage composed by the owner, tickLower and tickUpper
                  /// @return _liquidity The amount of liquidity in the position,
                  /// Returns feeGrowthInside0LastX128 fee growth of token0 inside the tick range as of the last mint/burn/poke,
                  /// Returns feeGrowthInside1LastX128 fee growth of token1 inside the tick range as of the last mint/burn/poke,
                  /// Returns tokensOwed0 the computed amount of token0 owed to the position as of the last mint/burn/poke,
                  /// Returns tokensOwed1 the computed amount of token1 owed to the position as of the last mint/burn/poke
                  function positions(bytes32 key)
                      external
                      view
                      returns (
                          uint128 _liquidity,
                          uint256 feeGrowthInside0LastX128,
                          uint256 feeGrowthInside1LastX128,
                          uint128 tokensOwed0,
                          uint128 tokensOwed1
                      );
                  /// @notice Returns data about a specific observation index
                  /// @param index The element of the observations array to fetch
                  /// @dev You most likely want to use #observe() instead of this method to get an observation as of some amount of time
                  /// ago, rather than at a specific index in the array.
                  /// @return blockTimestamp The timestamp of the observation,
                  /// Returns tickCumulative the tick multiplied by seconds elapsed for the life of the pool as of the observation timestamp,
                  /// Returns secondsPerLiquidityCumulativeX128 the seconds per in range liquidity for the life of the pool as of the observation timestamp,
                  /// Returns initialized whether the observation has been initialized and the values are safe to use
                  function observations(uint256 index)
                      external
                      view
                      returns (
                          uint32 blockTimestamp,
                          int56 tickCumulative,
                          uint160 secondsPerLiquidityCumulativeX128,
                          bool initialized
                      );
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Pool state that is not stored
              /// @notice Contains view functions to provide information about the pool that is computed rather than stored on the
              /// blockchain. The functions here may have variable gas costs.
              interface IUniswapV3PoolDerivedState {
                  /// @notice Returns the cumulative tick and liquidity as of each timestamp `secondsAgo` from the current block timestamp
                  /// @dev To get a time weighted average tick or liquidity-in-range, you must call this with two values, one representing
                  /// the beginning of the period and another for the end of the period. E.g., to get the last hour time-weighted average tick,
                  /// you must call it with secondsAgos = [3600, 0].
                  /// @dev The time weighted average tick represents the geometric time weighted average price of the pool, in
                  /// log base sqrt(1.0001) of token1 / token0. The TickMath library can be used to go from a tick value to a ratio.
                  /// @param secondsAgos From how long ago each cumulative tick and liquidity value should be returned
                  /// @return tickCumulatives Cumulative tick values as of each `secondsAgos` from the current block timestamp
                  /// @return secondsPerLiquidityCumulativeX128s Cumulative seconds per liquidity-in-range value as of each `secondsAgos` from the current block
                  /// timestamp
                  function observe(uint32[] calldata secondsAgos)
                      external
                      view
                      returns (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s);
                  /// @notice Returns a snapshot of the tick cumulative, seconds per liquidity and seconds inside a tick range
                  /// @dev Snapshots must only be compared to other snapshots, taken over a period for which a position existed.
                  /// I.e., snapshots cannot be compared if a position is not held for the entire period between when the first
                  /// snapshot is taken and the second snapshot is taken.
                  /// @param tickLower The lower tick of the range
                  /// @param tickUpper The upper tick of the range
                  /// @return tickCumulativeInside The snapshot of the tick accumulator for the range
                  /// @return secondsPerLiquidityInsideX128 The snapshot of seconds per liquidity for the range
                  /// @return secondsInside The snapshot of seconds per liquidity for the range
                  function snapshotCumulativesInside(int24 tickLower, int24 tickUpper)
                      external
                      view
                      returns (
                          int56 tickCumulativeInside,
                          uint160 secondsPerLiquidityInsideX128,
                          uint32 secondsInside
                      );
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Permissionless pool actions
              /// @notice Contains pool methods that can be called by anyone
              interface IUniswapV3PoolActions {
                  /// @notice Sets the initial price for the pool
                  /// @dev Price is represented as a sqrt(amountToken1/amountToken0) Q64.96 value
                  /// @param sqrtPriceX96 the initial sqrt price of the pool as a Q64.96
                  function initialize(uint160 sqrtPriceX96) external;
                  /// @notice Adds liquidity for the given recipient/tickLower/tickUpper position
                  /// @dev The caller of this method receives a callback in the form of IUniswapV3MintCallback#uniswapV3MintCallback
                  /// in which they must pay any token0 or token1 owed for the liquidity. The amount of token0/token1 due depends
                  /// on tickLower, tickUpper, the amount of liquidity, and the current price.
                  /// @param recipient The address for which the liquidity will be created
                  /// @param tickLower The lower tick of the position in which to add liquidity
                  /// @param tickUpper The upper tick of the position in which to add liquidity
                  /// @param amount The amount of liquidity to mint
                  /// @param data Any data that should be passed through to the callback
                  /// @return amount0 The amount of token0 that was paid to mint the given amount of liquidity. Matches the value in the callback
                  /// @return amount1 The amount of token1 that was paid to mint the given amount of liquidity. Matches the value in the callback
                  function mint(
                      address recipient,
                      int24 tickLower,
                      int24 tickUpper,
                      uint128 amount,
                      bytes calldata data
                  ) external returns (uint256 amount0, uint256 amount1);
                  /// @notice Collects tokens owed to a position
                  /// @dev Does not recompute fees earned, which must be done either via mint or burn of any amount of liquidity.
                  /// Collect must be called by the position owner. To withdraw only token0 or only token1, amount0Requested or
                  /// amount1Requested may be set to zero. To withdraw all tokens owed, caller may pass any value greater than the
                  /// actual tokens owed, e.g. type(uint128).max. Tokens owed may be from accumulated swap fees or burned liquidity.
                  /// @param recipient The address which should receive the fees collected
                  /// @param tickLower The lower tick of the position for which to collect fees
                  /// @param tickUpper The upper tick of the position for which to collect fees
                  /// @param amount0Requested How much token0 should be withdrawn from the fees owed
                  /// @param amount1Requested How much token1 should be withdrawn from the fees owed
                  /// @return amount0 The amount of fees collected in token0
                  /// @return amount1 The amount of fees collected in token1
                  function collect(
                      address recipient,
                      int24 tickLower,
                      int24 tickUpper,
                      uint128 amount0Requested,
                      uint128 amount1Requested
                  ) external returns (uint128 amount0, uint128 amount1);
                  /// @notice Burn liquidity from the sender and account tokens owed for the liquidity to the position
                  /// @dev Can be used to trigger a recalculation of fees owed to a position by calling with an amount of 0
                  /// @dev Fees must be collected separately via a call to #collect
                  /// @param tickLower The lower tick of the position for which to burn liquidity
                  /// @param tickUpper The upper tick of the position for which to burn liquidity
                  /// @param amount How much liquidity to burn
                  /// @return amount0 The amount of token0 sent to the recipient
                  /// @return amount1 The amount of token1 sent to the recipient
                  function burn(
                      int24 tickLower,
                      int24 tickUpper,
                      uint128 amount
                  ) external returns (uint256 amount0, uint256 amount1);
                  /// @notice Swap token0 for token1, or token1 for token0
                  /// @dev The caller of this method receives a callback in the form of IUniswapV3SwapCallback#uniswapV3SwapCallback
                  /// @param recipient The address to receive the output of the swap
                  /// @param zeroForOne The direction of the swap, true for token0 to token1, false for token1 to token0
                  /// @param amountSpecified The amount of the swap, which implicitly configures the swap as exact input (positive), or exact output (negative)
                  /// @param sqrtPriceLimitX96 The Q64.96 sqrt price limit. If zero for one, the price cannot be less than this
                  /// value after the swap. If one for zero, the price cannot be greater than this value after the swap
                  /// @param data Any data to be passed through to the callback
                  /// @return amount0 The delta of the balance of token0 of the pool, exact when negative, minimum when positive
                  /// @return amount1 The delta of the balance of token1 of the pool, exact when negative, minimum when positive
                  function swap(
                      address recipient,
                      bool zeroForOne,
                      int256 amountSpecified,
                      uint160 sqrtPriceLimitX96,
                      bytes calldata data
                  ) external returns (int256 amount0, int256 amount1);
                  /// @notice Receive token0 and/or token1 and pay it back, plus a fee, in the callback
                  /// @dev The caller of this method receives a callback in the form of IUniswapV3FlashCallback#uniswapV3FlashCallback
                  /// @dev Can be used to donate underlying tokens pro-rata to currently in-range liquidity providers by calling
                  /// with 0 amount{0,1} and sending the donation amount(s) from the callback
                  /// @param recipient The address which will receive the token0 and token1 amounts
                  /// @param amount0 The amount of token0 to send
                  /// @param amount1 The amount of token1 to send
                  /// @param data Any data to be passed through to the callback
                  function flash(
                      address recipient,
                      uint256 amount0,
                      uint256 amount1,
                      bytes calldata data
                  ) external;
                  /// @notice Increase the maximum number of price and liquidity observations that this pool will store
                  /// @dev This method is no-op if the pool already has an observationCardinalityNext greater than or equal to
                  /// the input observationCardinalityNext.
                  /// @param observationCardinalityNext The desired minimum number of observations for the pool to store
                  function increaseObservationCardinalityNext(uint16 observationCardinalityNext) external;
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Permissioned pool actions
              /// @notice Contains pool methods that may only be called by the factory owner
              interface IUniswapV3PoolOwnerActions {
                  /// @notice Set the denominator of the protocol's % share of the fees
                  /// @param feeProtocol0 new protocol fee for token0 of the pool
                  /// @param feeProtocol1 new protocol fee for token1 of the pool
                  function setFeeProtocol(uint8 feeProtocol0, uint8 feeProtocol1) external;
                  /// @notice Collect the protocol fee accrued to the pool
                  /// @param recipient The address to which collected protocol fees should be sent
                  /// @param amount0Requested The maximum amount of token0 to send, can be 0 to collect fees in only token1
                  /// @param amount1Requested The maximum amount of token1 to send, can be 0 to collect fees in only token0
                  /// @return amount0 The protocol fee collected in token0
                  /// @return amount1 The protocol fee collected in token1
                  function collectProtocol(
                      address recipient,
                      uint128 amount0Requested,
                      uint128 amount1Requested
                  ) external returns (uint128 amount0, uint128 amount1);
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Events emitted by a pool
              /// @notice Contains all events emitted by the pool
              interface IUniswapV3PoolEvents {
                  /// @notice Emitted exactly once by a pool when #initialize is first called on the pool
                  /// @dev Mint/Burn/Swap cannot be emitted by the pool before Initialize
                  /// @param sqrtPriceX96 The initial sqrt price of the pool, as a Q64.96
                  /// @param tick The initial tick of the pool, i.e. log base 1.0001 of the starting price of the pool
                  event Initialize(uint160 sqrtPriceX96, int24 tick);
                  /// @notice Emitted when liquidity is minted for a given position
                  /// @param sender The address that minted the liquidity
                  /// @param owner The owner of the position and recipient of any minted liquidity
                  /// @param tickLower The lower tick of the position
                  /// @param tickUpper The upper tick of the position
                  /// @param amount The amount of liquidity minted to the position range
                  /// @param amount0 How much token0 was required for the minted liquidity
                  /// @param amount1 How much token1 was required for the minted liquidity
                  event Mint(
                      address sender,
                      address indexed owner,
                      int24 indexed tickLower,
                      int24 indexed tickUpper,
                      uint128 amount,
                      uint256 amount0,
                      uint256 amount1
                  );
                  /// @notice Emitted when fees are collected by the owner of a position
                  /// @dev Collect events may be emitted with zero amount0 and amount1 when the caller chooses not to collect fees
                  /// @param owner The owner of the position for which fees are collected
                  /// @param tickLower The lower tick of the position
                  /// @param tickUpper The upper tick of the position
                  /// @param amount0 The amount of token0 fees collected
                  /// @param amount1 The amount of token1 fees collected
                  event Collect(
                      address indexed owner,
                      address recipient,
                      int24 indexed tickLower,
                      int24 indexed tickUpper,
                      uint128 amount0,
                      uint128 amount1
                  );
                  /// @notice Emitted when a position's liquidity is removed
                  /// @dev Does not withdraw any fees earned by the liquidity position, which must be withdrawn via #collect
                  /// @param owner The owner of the position for which liquidity is removed
                  /// @param tickLower The lower tick of the position
                  /// @param tickUpper The upper tick of the position
                  /// @param amount The amount of liquidity to remove
                  /// @param amount0 The amount of token0 withdrawn
                  /// @param amount1 The amount of token1 withdrawn
                  event Burn(
                      address indexed owner,
                      int24 indexed tickLower,
                      int24 indexed tickUpper,
                      uint128 amount,
                      uint256 amount0,
                      uint256 amount1
                  );
                  /// @notice Emitted by the pool for any swaps between token0 and token1
                  /// @param sender The address that initiated the swap call, and that received the callback
                  /// @param recipient The address that received the output of the swap
                  /// @param amount0 The delta of the token0 balance of the pool
                  /// @param amount1 The delta of the token1 balance of the pool
                  /// @param sqrtPriceX96 The sqrt(price) of the pool after the swap, as a Q64.96
                  /// @param liquidity The liquidity of the pool after the swap
                  /// @param tick The log base 1.0001 of price of the pool after the swap
                  event Swap(
                      address indexed sender,
                      address indexed recipient,
                      int256 amount0,
                      int256 amount1,
                      uint160 sqrtPriceX96,
                      uint128 liquidity,
                      int24 tick
                  );
                  /// @notice Emitted by the pool for any flashes of token0/token1
                  /// @param sender The address that initiated the swap call, and that received the callback
                  /// @param recipient The address that received the tokens from flash
                  /// @param amount0 The amount of token0 that was flashed
                  /// @param amount1 The amount of token1 that was flashed
                  /// @param paid0 The amount of token0 paid for the flash, which can exceed the amount0 plus the fee
                  /// @param paid1 The amount of token1 paid for the flash, which can exceed the amount1 plus the fee
                  event Flash(
                      address indexed sender,
                      address indexed recipient,
                      uint256 amount0,
                      uint256 amount1,
                      uint256 paid0,
                      uint256 paid1
                  );
                  /// @notice Emitted by the pool for increases to the number of observations that can be stored
                  /// @dev observationCardinalityNext is not the observation cardinality until an observation is written at the index
                  /// just before a mint/swap/burn.
                  /// @param observationCardinalityNextOld The previous value of the next observation cardinality
                  /// @param observationCardinalityNextNew The updated value of the next observation cardinality
                  event IncreaseObservationCardinalityNext(
                      uint16 observationCardinalityNextOld,
                      uint16 observationCardinalityNextNew
                  );
                  /// @notice Emitted when the protocol fee is changed by the pool
                  /// @param feeProtocol0Old The previous value of the token0 protocol fee
                  /// @param feeProtocol1Old The previous value of the token1 protocol fee
                  /// @param feeProtocol0New The updated value of the token0 protocol fee
                  /// @param feeProtocol1New The updated value of the token1 protocol fee
                  event SetFeeProtocol(uint8 feeProtocol0Old, uint8 feeProtocol1Old, uint8 feeProtocol0New, uint8 feeProtocol1New);
                  /// @notice Emitted when the collected protocol fees are withdrawn by the factory owner
                  /// @param sender The address that collects the protocol fees
                  /// @param recipient The address that receives the collected protocol fees
                  /// @param amount0 The amount of token0 protocol fees that is withdrawn
                  /// @param amount0 The amount of token1 protocol fees that is withdrawn
                  event CollectProtocol(address indexed sender, address indexed recipient, uint128 amount0, uint128 amount1);
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title BitMath
              /// @dev This library provides functionality for computing bit properties of an unsigned integer
              library BitMath {
                  /// @notice Returns the index of the most significant bit of the number,
                  ///     where the least significant bit is at index 0 and the most significant bit is at index 255
                  /// @dev The function satisfies the property:
                  ///     x >= 2**mostSignificantBit(x) and x < 2**(mostSignificantBit(x)+1)
                  /// @param x the value for which to compute the most significant bit, must be greater than 0
                  /// @return r the index of the most significant bit
                  function mostSignificantBit(uint256 x) internal pure returns (uint8 r) {
                      require(x > 0);
                      if (x >= 0x100000000000000000000000000000000) {
                          x >>= 128;
                          r += 128;
                      }
                      if (x >= 0x10000000000000000) {
                          x >>= 64;
                          r += 64;
                      }
                      if (x >= 0x100000000) {
                          x >>= 32;
                          r += 32;
                      }
                      if (x >= 0x10000) {
                          x >>= 16;
                          r += 16;
                      }
                      if (x >= 0x100) {
                          x >>= 8;
                          r += 8;
                      }
                      if (x >= 0x10) {
                          x >>= 4;
                          r += 4;
                      }
                      if (x >= 0x4) {
                          x >>= 2;
                          r += 2;
                      }
                      if (x >= 0x2) r += 1;
                  }
                  /// @notice Returns the index of the least significant bit of the number,
                  ///     where the least significant bit is at index 0 and the most significant bit is at index 255
                  /// @dev The function satisfies the property:
                  ///     (x & 2**leastSignificantBit(x)) != 0 and (x & (2**(leastSignificantBit(x)) - 1)) == 0)
                  /// @param x the value for which to compute the least significant bit, must be greater than 0
                  /// @return r the index of the least significant bit
                  function leastSignificantBit(uint256 x) internal pure returns (uint8 r) {
                      require(x > 0);
                      r = 255;
                      if (x & type(uint128).max > 0) {
                          r -= 128;
                      } else {
                          x >>= 128;
                      }
                      if (x & type(uint64).max > 0) {
                          r -= 64;
                      } else {
                          x >>= 64;
                      }
                      if (x & type(uint32).max > 0) {
                          r -= 32;
                      } else {
                          x >>= 32;
                      }
                      if (x & type(uint16).max > 0) {
                          r -= 16;
                      } else {
                          x >>= 16;
                      }
                      if (x & type(uint8).max > 0) {
                          r -= 8;
                      } else {
                          x >>= 8;
                      }
                      if (x & 0xf > 0) {
                          r -= 4;
                      } else {
                          x >>= 4;
                      }
                      if (x & 0x3 > 0) {
                          r -= 2;
                      } else {
                          x >>= 2;
                      }
                      if (x & 0x1 > 0) r -= 1;
                  }
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.5.0;
              /// @title Math functions that do not check inputs or outputs
              /// @notice Contains methods that perform common math functions but do not do any overflow or underflow checks
              library UnsafeMath {
                  /// @notice Returns ceil(x / y)
                  /// @dev division by 0 has unspecified behavior, and must be checked externally
                  /// @param x The dividend
                  /// @param y The divisor
                  /// @return z The quotient, ceil(x / y)
                  function divRoundingUp(uint256 x, uint256 y) internal pure returns (uint256 z) {
                      assembly {
                          z := add(div(x, y), gt(mod(x, y), 0))
                      }
                  }
              }
              // SPDX-License-Identifier: GPL-2.0-or-later
              pragma solidity >=0.4.0;
              /// @title FixedPoint96
              /// @notice A library for handling binary fixed point numbers, see https://en.wikipedia.org/wiki/Q_(number_format)
              /// @dev Used in SqrtPriceMath.sol
              library FixedPoint96 {
                  uint8 internal constant RESOLUTION = 96;
                  uint256 internal constant Q96 = 0x1000000000000000000000000;
              }
              

              File 5 of 6: Spender
              {"Constants.84ef19f8.sol":{"content":"// SPDX-License-Identifier: MIT\r\n\r\npragma solidity ^0.6.0;\r\n\r\nlibrary Constants {\r\n    address internal constant ETH = 0x0000000000000000000000000000000000000000;\r\n}\r\n"},"Spender.3372a096.sol":{"content":"// SPDX-License-Identifier: MIT\r\n\r\npragma solidity ^0.6.0;\r\n\r\nimport \"./Constants.84ef19f8.sol\";\r\n\r\ncontract Spender {\r\n    address public immutable metaswap;\r\n\r\n    constructor() public {\r\n        metaswap = msg.sender;\r\n    }\r\n\r\n    /// @dev Receives ether from swaps\r\n    fallback() external payable {}\r\n\r\n    function swap(address adapter, bytes calldata data) external payable {\r\n        require(msg.sender == metaswap, \"FORBIDDEN\");\r\n        require(adapter != address(0), \"ADAPTER_NOT_PROVIDED\");\r\n        _delegate(adapter, data, \"ADAPTER_DELEGATECALL_FAILED\");\r\n    }\r\n\r\n    /**\r\n     * @dev Performs a delegatecall and bubbles up the errors, adapted from\r\n     * https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Address.sol\r\n     * @param target Address of the contract to delegatecall\r\n     * @param data Data passed in the delegatecall\r\n     * @param errorMessage Fallback revert reason\r\n     */\r\n    function _delegate(\r\n        address target,\r\n        bytes memory data,\r\n        string memory errorMessage\r\n    ) private returns (bytes memory) {\r\n        // solhint-disable-next-line avoid-low-level-calls\r\n        (bool success, bytes memory returndata) = target.delegatecall(data);\r\n        if (success) {\r\n            return returndata;\r\n        } else {\r\n            // Look for revert reason and bubble it up if present\r\n            if (returndata.length \u003e 0) {\r\n                // The easiest way to bubble the revert reason is using memory via assembly\r\n\r\n                // solhint-disable-next-line no-inline-assembly\r\n                assembly {\r\n                    let returndata_size := mload(returndata)\r\n                    revert(add(32, returndata), returndata_size)\r\n                }\r\n            } else {\r\n                revert(errorMessage);\r\n            }\r\n        }\r\n    }\r\n}\r\n"}}

              File 6 of 6: TetherToken
              pragma solidity ^0.4.17;
              
              /**
               * @title SafeMath
               * @dev Math operations with safety checks that throw on error
               */
              library SafeMath {
                  function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                      if (a == 0) {
                          return 0;
                      }
                      uint256 c = a * b;
                      assert(c / a == b);
                      return c;
                  }
              
                  function div(uint256 a, uint256 b) internal pure returns (uint256) {
                      // assert(b > 0); // Solidity automatically throws when dividing by 0
                      uint256 c = a / b;
                      // assert(a == b * c + a % b); // There is no case in which this doesn't hold
                      return c;
                  }
              
                  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                      assert(b <= a);
                      return a - b;
                  }
              
                  function add(uint256 a, uint256 b) internal pure returns (uint256) {
                      uint256 c = a + b;
                      assert(c >= a);
                      return c;
                  }
              }
              
              /**
               * @title Ownable
               * @dev The Ownable contract has an owner address, and provides basic authorization control
               * functions, this simplifies the implementation of "user permissions".
               */
              contract Ownable {
                  address public owner;
              
                  /**
                    * @dev The Ownable constructor sets the original `owner` of the contract to the sender
                    * account.
                    */
                  function Ownable() public {
                      owner = msg.sender;
                  }
              
                  /**
                    * @dev Throws if called by any account other than the owner.
                    */
                  modifier onlyOwner() {
                      require(msg.sender == owner);
                      _;
                  }
              
                  /**
                  * @dev Allows the current owner to transfer control of the contract to a newOwner.
                  * @param newOwner The address to transfer ownership to.
                  */
                  function transferOwnership(address newOwner) public onlyOwner {
                      if (newOwner != address(0)) {
                          owner = newOwner;
                      }
                  }
              
              }
              
              /**
               * @title ERC20Basic
               * @dev Simpler version of ERC20 interface
               * @dev see https://github.com/ethereum/EIPs/issues/20
               */
              contract ERC20Basic {
                  uint public _totalSupply;
                  function totalSupply() public constant returns (uint);
                  function balanceOf(address who) public constant returns (uint);
                  function transfer(address to, uint value) public;
                  event Transfer(address indexed from, address indexed to, uint value);
              }
              
              /**
               * @title ERC20 interface
               * @dev see https://github.com/ethereum/EIPs/issues/20
               */
              contract ERC20 is ERC20Basic {
                  function allowance(address owner, address spender) public constant returns (uint);
                  function transferFrom(address from, address to, uint value) public;
                  function approve(address spender, uint value) public;
                  event Approval(address indexed owner, address indexed spender, uint value);
              }
              
              /**
               * @title Basic token
               * @dev Basic version of StandardToken, with no allowances.
               */
              contract BasicToken is Ownable, ERC20Basic {
                  using SafeMath for uint;
              
                  mapping(address => uint) public balances;
              
                  // additional variables for use if transaction fees ever became necessary
                  uint public basisPointsRate = 0;
                  uint public maximumFee = 0;
              
                  /**
                  * @dev Fix for the ERC20 short address attack.
                  */
                  modifier onlyPayloadSize(uint size) {
                      require(!(msg.data.length < size + 4));
                      _;
                  }
              
                  /**
                  * @dev transfer token for a specified address
                  * @param _to The address to transfer to.
                  * @param _value The amount to be transferred.
                  */
                  function transfer(address _to, uint _value) public onlyPayloadSize(2 * 32) {
                      uint fee = (_value.mul(basisPointsRate)).div(10000);
                      if (fee > maximumFee) {
                          fee = maximumFee;
                      }
                      uint sendAmount = _value.sub(fee);
                      balances[msg.sender] = balances[msg.sender].sub(_value);
                      balances[_to] = balances[_to].add(sendAmount);
                      if (fee > 0) {
                          balances[owner] = balances[owner].add(fee);
                          Transfer(msg.sender, owner, fee);
                      }
                      Transfer(msg.sender, _to, sendAmount);
                  }
              
                  /**
                  * @dev Gets the balance of the specified address.
                  * @param _owner The address to query the the balance of.
                  * @return An uint representing the amount owned by the passed address.
                  */
                  function balanceOf(address _owner) public constant returns (uint balance) {
                      return balances[_owner];
                  }
              
              }
              
              /**
               * @title Standard ERC20 token
               *
               * @dev Implementation of the basic standard token.
               * @dev https://github.com/ethereum/EIPs/issues/20
               * @dev Based oncode by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
               */
              contract StandardToken is BasicToken, ERC20 {
              
                  mapping (address => mapping (address => uint)) public allowed;
              
                  uint public constant MAX_UINT = 2**256 - 1;
              
                  /**
                  * @dev Transfer tokens from one address to another
                  * @param _from address The address which you want to send tokens from
                  * @param _to address The address which you want to transfer to
                  * @param _value uint the amount of tokens to be transferred
                  */
                  function transferFrom(address _from, address _to, uint _value) public onlyPayloadSize(3 * 32) {
                      var _allowance = allowed[_from][msg.sender];
              
                      // Check is not needed because sub(_allowance, _value) will already throw if this condition is not met
                      // if (_value > _allowance) throw;
              
                      uint fee = (_value.mul(basisPointsRate)).div(10000);
                      if (fee > maximumFee) {
                          fee = maximumFee;
                      }
                      if (_allowance < MAX_UINT) {
                          allowed[_from][msg.sender] = _allowance.sub(_value);
                      }
                      uint sendAmount = _value.sub(fee);
                      balances[_from] = balances[_from].sub(_value);
                      balances[_to] = balances[_to].add(sendAmount);
                      if (fee > 0) {
                          balances[owner] = balances[owner].add(fee);
                          Transfer(_from, owner, fee);
                      }
                      Transfer(_from, _to, sendAmount);
                  }
              
                  /**
                  * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
                  * @param _spender The address which will spend the funds.
                  * @param _value The amount of tokens to be spent.
                  */
                  function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {
              
                      // To change the approve amount you first have to reduce the addresses`
                      //  allowance to zero by calling `approve(_spender, 0)` if it is not
                      //  already 0 to mitigate the race condition described here:
                      //  https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                      require(!((_value != 0) && (allowed[msg.sender][_spender] != 0)));
              
                      allowed[msg.sender][_spender] = _value;
                      Approval(msg.sender, _spender, _value);
                  }
              
                  /**
                  * @dev Function to check the amount of tokens than an owner allowed to a spender.
                  * @param _owner address The address which owns the funds.
                  * @param _spender address The address which will spend the funds.
                  * @return A uint specifying the amount of tokens still available for the spender.
                  */
                  function allowance(address _owner, address _spender) public constant returns (uint remaining) {
                      return allowed[_owner][_spender];
                  }
              
              }
              
              
              /**
               * @title Pausable
               * @dev Base contract which allows children to implement an emergency stop mechanism.
               */
              contract Pausable is Ownable {
                event Pause();
                event Unpause();
              
                bool public paused = false;
              
              
                /**
                 * @dev Modifier to make a function callable only when the contract is not paused.
                 */
                modifier whenNotPaused() {
                  require(!paused);
                  _;
                }
              
                /**
                 * @dev Modifier to make a function callable only when the contract is paused.
                 */
                modifier whenPaused() {
                  require(paused);
                  _;
                }
              
                /**
                 * @dev called by the owner to pause, triggers stopped state
                 */
                function pause() onlyOwner whenNotPaused public {
                  paused = true;
                  Pause();
                }
              
                /**
                 * @dev called by the owner to unpause, returns to normal state
                 */
                function unpause() onlyOwner whenPaused public {
                  paused = false;
                  Unpause();
                }
              }
              
              contract BlackList is Ownable, BasicToken {
              
                  /////// Getters to allow the same blacklist to be used also by other contracts (including upgraded Tether) ///////
                  function getBlackListStatus(address _maker) external constant returns (bool) {
                      return isBlackListed[_maker];
                  }
              
                  function getOwner() external constant returns (address) {
                      return owner;
                  }
              
                  mapping (address => bool) public isBlackListed;
                  
                  function addBlackList (address _evilUser) public onlyOwner {
                      isBlackListed[_evilUser] = true;
                      AddedBlackList(_evilUser);
                  }
              
                  function removeBlackList (address _clearedUser) public onlyOwner {
                      isBlackListed[_clearedUser] = false;
                      RemovedBlackList(_clearedUser);
                  }
              
                  function destroyBlackFunds (address _blackListedUser) public onlyOwner {
                      require(isBlackListed[_blackListedUser]);
                      uint dirtyFunds = balanceOf(_blackListedUser);
                      balances[_blackListedUser] = 0;
                      _totalSupply -= dirtyFunds;
                      DestroyedBlackFunds(_blackListedUser, dirtyFunds);
                  }
              
                  event DestroyedBlackFunds(address _blackListedUser, uint _balance);
              
                  event AddedBlackList(address _user);
              
                  event RemovedBlackList(address _user);
              
              }
              
              contract UpgradedStandardToken is StandardToken{
                  // those methods are called by the legacy contract
                  // and they must ensure msg.sender to be the contract address
                  function transferByLegacy(address from, address to, uint value) public;
                  function transferFromByLegacy(address sender, address from, address spender, uint value) public;
                  function approveByLegacy(address from, address spender, uint value) public;
              }
              
              contract TetherToken is Pausable, StandardToken, BlackList {
              
                  string public name;
                  string public symbol;
                  uint public decimals;
                  address public upgradedAddress;
                  bool public deprecated;
              
                  //  The contract can be initialized with a number of tokens
                  //  All the tokens are deposited to the owner address
                  //
                  // @param _balance Initial supply of the contract
                  // @param _name Token Name
                  // @param _symbol Token symbol
                  // @param _decimals Token decimals
                  function TetherToken(uint _initialSupply, string _name, string _symbol, uint _decimals) public {
                      _totalSupply = _initialSupply;
                      name = _name;
                      symbol = _symbol;
                      decimals = _decimals;
                      balances[owner] = _initialSupply;
                      deprecated = false;
                  }
              
                  // Forward ERC20 methods to upgraded contract if this one is deprecated
                  function transfer(address _to, uint _value) public whenNotPaused {
                      require(!isBlackListed[msg.sender]);
                      if (deprecated) {
                          return UpgradedStandardToken(upgradedAddress).transferByLegacy(msg.sender, _to, _value);
                      } else {
                          return super.transfer(_to, _value);
                      }
                  }
              
                  // Forward ERC20 methods to upgraded contract if this one is deprecated
                  function transferFrom(address _from, address _to, uint _value) public whenNotPaused {
                      require(!isBlackListed[_from]);
                      if (deprecated) {
                          return UpgradedStandardToken(upgradedAddress).transferFromByLegacy(msg.sender, _from, _to, _value);
                      } else {
                          return super.transferFrom(_from, _to, _value);
                      }
                  }
              
                  // Forward ERC20 methods to upgraded contract if this one is deprecated
                  function balanceOf(address who) public constant returns (uint) {
                      if (deprecated) {
                          return UpgradedStandardToken(upgradedAddress).balanceOf(who);
                      } else {
                          return super.balanceOf(who);
                      }
                  }
              
                  // Forward ERC20 methods to upgraded contract if this one is deprecated
                  function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {
                      if (deprecated) {
                          return UpgradedStandardToken(upgradedAddress).approveByLegacy(msg.sender, _spender, _value);
                      } else {
                          return super.approve(_spender, _value);
                      }
                  }
              
                  // Forward ERC20 methods to upgraded contract if this one is deprecated
                  function allowance(address _owner, address _spender) public constant returns (uint remaining) {
                      if (deprecated) {
                          return StandardToken(upgradedAddress).allowance(_owner, _spender);
                      } else {
                          return super.allowance(_owner, _spender);
                      }
                  }
              
                  // deprecate current contract in favour of a new one
                  function deprecate(address _upgradedAddress) public onlyOwner {
                      deprecated = true;
                      upgradedAddress = _upgradedAddress;
                      Deprecate(_upgradedAddress);
                  }
              
                  // deprecate current contract if favour of a new one
                  function totalSupply() public constant returns (uint) {
                      if (deprecated) {
                          return StandardToken(upgradedAddress).totalSupply();
                      } else {
                          return _totalSupply;
                      }
                  }
              
                  // Issue a new amount of tokens
                  // these tokens are deposited into the owner address
                  //
                  // @param _amount Number of tokens to be issued
                  function issue(uint amount) public onlyOwner {
                      require(_totalSupply + amount > _totalSupply);
                      require(balances[owner] + amount > balances[owner]);
              
                      balances[owner] += amount;
                      _totalSupply += amount;
                      Issue(amount);
                  }
              
                  // Redeem tokens.
                  // These tokens are withdrawn from the owner address
                  // if the balance must be enough to cover the redeem
                  // or the call will fail.
                  // @param _amount Number of tokens to be issued
                  function redeem(uint amount) public onlyOwner {
                      require(_totalSupply >= amount);
                      require(balances[owner] >= amount);
              
                      _totalSupply -= amount;
                      balances[owner] -= amount;
                      Redeem(amount);
                  }
              
                  function setParams(uint newBasisPoints, uint newMaxFee) public onlyOwner {
                      // Ensure transparency by hardcoding limit beyond which fees can never be added
                      require(newBasisPoints < 20);
                      require(newMaxFee < 50);
              
                      basisPointsRate = newBasisPoints;
                      maximumFee = newMaxFee.mul(10**decimals);
              
                      Params(basisPointsRate, maximumFee);
                  }
              
                  // Called when new token are issued
                  event Issue(uint amount);
              
                  // Called when tokens are redeemed
                  event Redeem(uint amount);
              
                  // Called when contract is deprecated
                  event Deprecate(address newAddress);
              
                  // Called if contract ever adds fees
                  event Params(uint feeBasisPoints, uint maxFee);
              }