// 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;
    }
}


/*
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DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES.

  17. Interpretation of Sections 15 and 16.

  If the disclaimer of warranty and limitation of liability provided
above cannot be given local legal effect according to their terms,
reviewing courts shall apply local law that most closely approximates
an absolute waiver of all civil liability in connection with the
Program, unless a warranty or assumption of liability accompanies a
copy of the Program in return for a fee.

                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

  If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.

  To do so, attach the following notices to the program.  It is safest
to attach them to the start of each source file to most effectively
state the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.

    <one line to give the program's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>

    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/>.

Also add information on how to contact you by electronic and paper mail.

  If the program does terminal interaction, make it output a short
notice like this when it starts in an interactive mode:

    <program>  Copyright (C) <year>  <name of author>
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, your program's commands
might be different; for a GUI interface, you would use an "about box".

  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU GPL, see
<http://www.gnu.org/licenses/>.

  The GNU General Public License does not permit incorporating your program
into proprietary programs.  If your program is a subroutine library, you
may consider it more useful to permit linking proprietary applications with
the library.  If this is what you want to do, use the GNU Lesser General
Public License instead of this License.  But first, please read
<http://www.gnu.org/philosophy/why-not-lgpl.html>.

*/

{"Address.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity \u003e=0.6.2 \u003c0.8.0;\n\n/**\n * @dev Collection of functions related to the address type\n */\nlibrary Address {\n    /**\n     * @dev Returns true if `account` is a contract.\n     *\n     * [IMPORTANT]\n     * ====\n     * It is unsafe to assume that an address for which this function returns\n     * false is an externally-owned account (EOA) and not a contract.\n     *\n     * Among others, `isContract` will return false for the following\n     * types of addresses:\n     *\n     *  - an externally-owned account\n     *  - a contract in construction\n     *  - an address where a contract will be created\n     *  - an address where a contract lived, but was destroyed\n     * ====\n     */\n    function isContract(address account) internal view returns (bool) {\n        // This method relies on extcodesize, which returns 0 for contracts in\n        // construction, since the code is only stored at the end of the\n        // constructor execution.\n\n        uint256 size;\n        // solhint-disable-next-line no-inline-assembly\n        assembly { size := extcodesize(account) }\n        return size \u003e 0;\n    }\n\n    /**\n     * @dev Replacement for Solidity\u0027s `transfer`: sends `amount` wei to\n     * `recipient`, forwarding all available gas and reverting on errors.\n     *\n     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost\n     * of certain opcodes, possibly making contracts go over the 2300 gas limit\n     * imposed by `transfer`, making them unable to receive funds via\n     * `transfer`. {sendValue} removes this limitation.\n     *\n     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].\n     *\n     * IMPORTANT: because control is transferred to `recipient`, care must be\n     * taken to not create reentrancy vulnerabilities. Consider using\n     * {ReentrancyGuard} or the\n     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].\n     */\n    function sendValue(address payable recipient, uint256 amount) internal {\n        require(address(this).balance \u003e= amount, \"Address: insufficient balance\");\n\n        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value\n        (bool success, ) = recipient.call{ value: amount }(\"\");\n        require(success, \"Address: unable to send value, recipient may have reverted\");\n    }\n\n    /**\n     * @dev Performs a Solidity function call using a low level `call`. A\n     * plain`call` is an unsafe replacement for a function call: use this\n     * function instead.\n     *\n     * If `target` reverts with a revert reason, it is bubbled up by this\n     * function (like regular Solidity function calls).\n     *\n     * Returns the raw returned data. To convert to the expected return value,\n     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].\n     *\n     * Requirements:\n     *\n     * - `target` must be a contract.\n     * - calling `target` with `data` must not revert.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(address target, bytes memory data) internal returns (bytes memory) {\n      return functionCall(target, data, \"Address: low-level call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with\n     * `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, 0, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but also transferring `value` wei to `target`.\n     *\n     * Requirements:\n     *\n     * - the calling contract must have an ETH balance of at least `value`.\n     * - the called Solidity function must be `payable`.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, value, \"Address: low-level call with value failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but\n     * with `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {\n        require(address(this).balance \u003e= value, \"Address: insufficient balance for call\");\n        require(isContract(target), \"Address: call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.call{ value: value }(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {\n        return functionStaticCall(target, data, \"Address: low-level static call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {\n        require(isContract(target), \"Address: static call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.staticcall(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {\n        return functionDelegateCall(target, data, \"Address: low-level delegate call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n        require(isContract(target), \"Address: delegate call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.delegatecall(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {\n        if (success) {\n            return returndata;\n        } else {\n            // Look for revert reason and bubble it up if present\n            if (returndata.length \u003e 0) {\n                // The easiest way to bubble the revert reason is using memory via assembly\n\n                // solhint-disable-next-line no-inline-assembly\n                assembly {\n                    let returndata_size := mload(returndata)\n                    revert(add(32, returndata), returndata_size)\n                }\n            } else {\n                revert(errorMessage);\n            }\n        }\n    }\n}\n"},"IERC20.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity \u003e=0.6.0 \u003c0.8.0;\n\n/**\n * @dev Interface of the ERC20 standard as defined in the EIP.\n */\ninterface IERC20 {\n    /**\n     * @dev Returns the amount of tokens in existence.\n     */\n    function totalSupply() external view returns (uint256);\n\n    /**\n     * @dev Returns the amount of tokens owned by `account`.\n     */\n    function balanceOf(address account) external view returns (uint256);\n\n    /**\n     * @dev Moves `amount` tokens from the caller\u0027s account to `recipient`.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transfer(address recipient, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Returns the remaining number of tokens that `spender` will be\n     * allowed to spend on behalf of `owner` through {transferFrom}. This is\n     * zero by default.\n     *\n     * This value changes when {approve} or {transferFrom} are called.\n     */\n    function allowance(address owner, address spender) external view returns (uint256);\n\n    /**\n     * @dev Sets `amount` as the allowance of `spender` over the caller\u0027s tokens.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * IMPORTANT: Beware that changing an allowance with this method brings the risk\n     * that someone may use both the old and the new allowance by unfortunate\n     * transaction ordering. One possible solution to mitigate this race\n     * condition is to first reduce the spender\u0027s allowance to 0 and set the\n     * desired value afterwards:\n     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729\n     *\n     * Emits an {Approval} event.\n     */\n    function approve(address spender, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Moves `amount` tokens from `sender` to `recipient` using the\n     * allowance mechanism. `amount` is then deducted from the caller\u0027s\n     * allowance.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Emitted when `value` tokens are moved from one account (`from`) to\n     * another (`to`).\n     *\n     * Note that `value` may be zero.\n     */\n    event Transfer(address indexed from, address indexed to, uint256 value);\n\n    /**\n     * @dev Emitted when the allowance of a `spender` for an `owner` is set by\n     * a call to {approve}. `value` is the new allowance.\n     */\n    event Approval(address indexed owner, address indexed spender, uint256 value);\n}\n"},"IPENDLE.sol":{"content":"// SPDX-License-Identifier: MIT\n/*\n * MIT License\n * ===========\n *\n * Permission is hereby granted, free of charge, to any person obtaining a copy\n * of this software and associated documentation files (the \"Software\"), to deal\n * in the Software without restriction, including without limitation the rights\n * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell\n * copies of the Software, and to permit persons to whom the Software is\n * furnished to do so, subject to the following conditions:\n *\n * The above copyright notice and this permission notice shall be included in all\n * copies or substantial portions of the Software.\n *\n * THE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR\n * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,\n * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE\n * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER\n * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,\n * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE\n */\n\npragma solidity 0.7.6;\n\nimport \"./IERC20.sol\";\n\ninterface IPENDLE is IERC20 {\n    function initiateConfigChanges(\n        uint256 _emissionRateMultiplierNumerator,\n        uint256 _terminalInflationRateNumerator,\n        address _liquidityIncentivesRecipient,\n        bool _isBurningAllowed\n    ) external;\n\n    function increaseAllowance(address spender, uint256 addedValue) external returns (bool);\n\n    function decreaseAllowance(address spender, uint256 subtractedValue) external returns (bool);\n\n    function burn(uint256 amount) external returns (bool);\n\n    function applyConfigChanges() external;\n\n    function claimLiquidityEmissions() external returns (uint256 totalEmissions);\n\n    function isPendleToken() external view returns (bool);\n\n    function getPriorVotes(address account, uint256 blockNumber) external view returns (uint256);\n\n    function startTime() external view returns (uint256);\n\n    function configChangesInitiated() external view returns (uint256);\n\n    function emissionRateMultiplierNumerator() external view returns (uint256);\n\n    function terminalInflationRateNumerator() external view returns (uint256);\n\n    function liquidityIncentivesRecipient() external view returns (address);\n\n    function isBurningAllowed() external view returns (bool);\n\n    function pendingEmissionRateMultiplierNumerator() external view returns (uint256);\n\n    function pendingTerminalInflationRateNumerator() external view returns (uint256);\n\n    function pendingLiquidityIncentivesRecipient() external view returns (address);\n\n    function pendingIsBurningAllowed() external view returns (bool);\n}\n"},"PENDLE.sol":{"content":"/* solhint-disable  const-name-snakecase*/\n// SPDX-License-Identifier: MIT\n/*\n * MIT License\n * ===========\n *\n * Permission is hereby granted, free of charge, to any person obtaining a copy\n * of this software and associated documentation files (the \"Software\"), to deal\n * in the Software without restriction, including without limitation the rights\n * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell\n * copies of the Software, and to permit persons to whom the Software is\n * furnished to do so, subject to the following conditions:\n *\n * The above copyright notice and this permission notice shall be included in all\n * copies or substantial portions of the Software.\n *\n * THE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR\n * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,\n * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE\n * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER\n * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,\n * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE\n */\npragma solidity 0.7.6;\npragma experimental ABIEncoderV2;\n\nimport \"./IPENDLE.sol\";\nimport \"./Permissions.sol\";\nimport \"./Withdrawable.sol\";\nimport \"./SafeMath.sol\";\n\n/**\n * @notice The mechanics for delegating votes to other accounts is adapted from Compound\n *   https://github.com/compound-finance/compound-protocol/blob/master/contracts/Governance/Comp.sol\n ***/\ncontract PENDLE is IPENDLE, Permissions, Withdrawable {\n    using SafeMath for uint256;\n\n    /// @notice A checkpoint for marking number of votes from a given block\n    struct Checkpoint {\n        uint32 fromBlock;\n        uint256 votes;\n    }\n\n    bool public constant override isPendleToken = true;\n    string public constant name = \"Pendle\";\n    string public constant symbol = \"PENDLE\";\n    uint8 public constant decimals = 18;\n    uint256 public override totalSupply;\n\n    uint256 private constant TEAM_INVESTOR_ADVISOR_AMOUNT = 94917125 * 1e18;\n    uint256 private constant ECOSYSTEM_FUND_TOKEN_AMOUNT = 46 * 1_000_000 * 1e18;\n    uint256 private constant PUBLIC_SALES_TOKEN_AMOUNT = 16582875 * 1e18;\n    uint256 private constant INITIAL_LIQUIDITY_EMISSION = 1200000 * 1e18;\n    uint256 private constant CONFIG_DENOMINATOR = 1_000_000_000_000;\n    uint256 private constant CONFIG_CHANGES_TIME_LOCK = 7 days;\n    uint256 public override emissionRateMultiplierNumerator;\n    uint256 public override terminalInflationRateNumerator;\n    address public override liquidityIncentivesRecipient;\n    bool public override isBurningAllowed;\n    uint256 public override pendingEmissionRateMultiplierNumerator;\n    uint256 public override pendingTerminalInflationRateNumerator;\n    address public override pendingLiquidityIncentivesRecipient;\n    bool public override pendingIsBurningAllowed;\n    uint256 public override configChangesInitiated;\n    uint256 public override startTime;\n    uint256 public lastWeeklyEmission;\n    uint256 public lastWeekEmissionSent;\n\n    mapping(address =\u003e mapping(address =\u003e uint256)) internal allowances;\n    mapping(address =\u003e uint256) internal balances;\n    mapping(address =\u003e address) public delegates;\n\n    /// @notice A record of votes checkpoints for each account, by index\n    mapping(address =\u003e mapping(uint32 =\u003e Checkpoint)) public checkpoints;\n\n    /// @notice The number of checkpoints for each account\n    mapping(address =\u003e uint32) public numCheckpoints;\n\n    /// @notice The EIP-712 typehash for the contract\u0027s domain\n    bytes32 public constant DOMAIN_TYPEHASH =\n        keccak256(\"EIP712Domain(string name,uint256 chainId,address verifyingContract)\");\n\n    /// @notice The EIP-712 typehash for the delegation struct used by the contract\n    bytes32 public constant DELEGATION_TYPEHASH =\n        keccak256(\"Delegation(address delegatee,uint256 nonce,uint256 expiry)\");\n\n    /// @notice A record of states for signing / validating signatures\n    mapping(address =\u003e uint256) public nonces;\n\n    /// @notice An event thats emitted when an account changes its delegate\n    event DelegateChanged(\n        address indexed delegator,\n        address indexed fromDelegate,\n        address indexed toDelegate\n    );\n\n    /// @notice An event thats emitted when a delegate account\u0027s vote balance changes\n    event DelegateVotesChanged(\n        address indexed delegate,\n        uint256 previousBalance,\n        uint256 newBalance\n    );\n\n    event PendingConfigChanges(\n        uint256 pendingEmissionRateMultiplierNumerator,\n        uint256 pendingTerminalInflationRateNumerator,\n        address pendingLiquidityIncentivesRecipient,\n        bool pendingIsBurningAllowed\n    );\n\n    event ConfigsChanged(\n        uint256 emissionRateMultiplierNumerator,\n        uint256 terminalInflationRateNumerator,\n        address liquidityIncentivesRecipient,\n        bool isBurningAllowed\n    );\n\n    /**\n     * @notice Construct a new PENDLE token\n     */\n    constructor(\n        address _governance,\n        address pendleTeamTokens,\n        address pendleEcosystemFund,\n        address salesMultisig,\n        address _liquidityIncentivesRecipient\n    ) Permissions(_governance) {\n        require(\n            pendleTeamTokens != address(0) \u0026\u0026\n                pendleEcosystemFund != address(0) \u0026\u0026\n                salesMultisig != address(0) \u0026\u0026\n                _liquidityIncentivesRecipient != address(0),\n            \"ZERO_ADDRESS\"\n        );\n        _mint(pendleTeamTokens, TEAM_INVESTOR_ADVISOR_AMOUNT);\n        _mint(pendleEcosystemFund, ECOSYSTEM_FUND_TOKEN_AMOUNT);\n        _mint(salesMultisig, PUBLIC_SALES_TOKEN_AMOUNT);\n        _mint(_liquidityIncentivesRecipient, INITIAL_LIQUIDITY_EMISSION * 26);\n        emissionRateMultiplierNumerator = (CONFIG_DENOMINATOR * 989) / 1000; // emission rate = 98.9% -\u003e 1.1% decay\n        terminalInflationRateNumerator = 379848538; // terminal inflation rate = 2% =\u003e weekly inflation = 0.0379848538%\n        liquidityIncentivesRecipient = _liquidityIncentivesRecipient;\n        startTime = block.timestamp;\n        lastWeeklyEmission = INITIAL_LIQUIDITY_EMISSION;\n        lastWeekEmissionSent = 26; // already done liquidity emissions for the first 26 weeks\n    }\n\n    /**\n     * @notice Approve `spender` to transfer up to `amount` from `src`\n     * @dev This will overwrite the approval amount for `spender`\n     *  and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)\n     * @param spender The address of the account which may transfer tokens\n     * @param amount The number of tokens that are approved\n     * @return Whether or not the approval succeeded\n     **/\n    function approve(address spender, uint256 amount) external override returns (bool) {\n        _approve(msg.sender, spender, amount);\n        return true;\n    }\n\n    /**\n     * @notice Transfer `amount` tokens from `msg.sender` to `dst`\n     * @param dst The address of the destination account\n     * @param amount The number of tokens to transfer\n     * @return Whether or not the transfer succeeded\n     */\n    function transfer(address dst, uint256 amount) external override returns (bool) {\n        _transfer(msg.sender, dst, amount);\n        return true;\n    }\n\n    /**\n     * @notice Transfer `amount` tokens from `src` to `dst`\n     * @param src The address of the source account\n     * @param dst The address of the destination account\n     * @param amount The number of tokens to transfer\n     * @return Whether or not the transfer succeeded\n     */\n    function transferFrom(\n        address src,\n        address dst,\n        uint256 amount\n    ) external override returns (bool) {\n        _transfer(src, dst, amount);\n        _approve(\n            src,\n            msg.sender,\n            allowances[src][msg.sender].sub(amount, \"TRANSFER_EXCEED_ALLOWANCE\")\n        );\n        return true;\n    }\n\n    /**\n     * @dev Increases the allowance granted to spender by the caller.\n     * @param spender The address to increase the allowance from.\n     * @param addedValue The amount allowance to add.\n     * @return returns true if allowance has increased, otherwise false\n     **/\n    function increaseAllowance(address spender, uint256 addedValue)\n        public\n        override\n        returns (bool)\n    {\n        _approve(msg.sender, spender, allowances[msg.sender][spender].add(addedValue));\n        return true;\n    }\n\n    /**\n     * @dev Decreases the allowance granted to spender by the caller.\n     * @param spender The address to reduce the allowance from.\n     * @param subtractedValue The amount allowance to subtract.\n     * @return Returns true if allowance has decreased, otherwise false.\n     **/\n    function decreaseAllowance(address spender, uint256 subtractedValue)\n        public\n        override\n        returns (bool)\n    {\n        _approve(\n            msg.sender,\n            spender,\n            allowances[msg.sender][spender].sub(subtractedValue, \"NEGATIVE_ALLOWANCE\")\n        );\n        return true;\n    }\n\n    /**\n     * @dev Burns an amount of tokens from the msg.sender\n     * @param amount The amount to burn\n     * @return Returns true if the operation is successful\n     **/\n    function burn(uint256 amount) public override returns (bool) {\n        require(isBurningAllowed, \"BURNING_NOT_ALLOWED\");\n        _burn(msg.sender, amount);\n        return true;\n    }\n\n    /**\n     * @notice Get the number of tokens `spender` is approved to spend on behalf of `account`\n     * @param account The address of the account holding the funds\n     * @param spender The address of the account spending the funds\n     * @return The number of tokens approved\n     **/\n    function allowance(address account, address spender) external view override returns (uint256) {\n        return allowances[account][spender];\n    }\n\n    /**\n     * @notice Get the number of tokens held by the `account`\n     * @param account The address of the account to get the balance of\n     * @return The number of tokens held\n     */\n    function balanceOf(address account) external view override returns (uint256) {\n        return balances[account];\n    }\n\n    /**\n     * @notice Gets the current votes balance for `account`\n     * @param account The address to get votes balance\n     * @return The number of current votes for `account`\n     */\n    function getCurrentVotes(address account) external view returns (uint256) {\n        uint32 nCheckpoints = numCheckpoints[account];\n        return nCheckpoints \u003e 0 ? checkpoints[account][nCheckpoints - 1].votes : 0;\n    }\n\n    /**\n     * @notice Delegate votes from `msg.sender` to `delegatee`\n     * @param delegatee The address to delegate votes to\n     */\n    function delegate(address delegatee) public {\n        return _delegate(msg.sender, delegatee);\n    }\n\n    /**\n     * @notice Delegates votes from signatory to `delegatee`\n     * @param delegatee The address to delegate votes to\n     * @param nonce The contract state required to match the signature\n     * @param expiry The time at which to expire the signature\n     * @param v The recovery byte of the signature\n     * @param r Half of the ECDSA signature pair\n     * @param s Half of the ECDSA signature pair\n     */\n    function delegateBySig(\n        address delegatee,\n        uint256 nonce,\n        uint256 expiry,\n        uint8 v,\n        bytes32 r,\n        bytes32 s\n    ) public {\n        bytes32 domainSeparator =\n            keccak256(\n                abi.encode(DOMAIN_TYPEHASH, keccak256(bytes(name)), getChainId(), address(this))\n            );\n        bytes32 structHash = keccak256(abi.encode(DELEGATION_TYPEHASH, delegatee, nonce, expiry));\n        bytes32 digest = keccak256(abi.encodePacked(\"\\x19\\x01\", domainSeparator, structHash));\n        address signatory = ecrecover(digest, v, r, s);\n        require(signatory != address(0), \"INVALID_SIGNATURE\");\n        require(nonce == nonces[signatory]++, \"INVALID_NONCE\");\n        require(block.timestamp \u003c= expiry, \"SIGNATURE_EXPIRED\");\n        return _delegate(signatory, delegatee);\n    }\n\n    /**\n     * @notice Determine the prior number of votes for an account as of a block number\n     * @dev Block number must be a finalized block or else\n                this function will revert to prevent misinformation\n     * @param account The address of the account to check\n     * @param blockNumber The block number to get the vote balance at\n     * @return The number of votes the account had as of the given block\n     */\n    function getPriorVotes(address account, uint256 blockNumber)\n        public\n        view\n        override\n        returns (uint256)\n    {\n        require(blockNumber \u003c block.number, \"NOT_YET_DETERMINED\");\n\n        uint32 nCheckpoints = numCheckpoints[account];\n        if (nCheckpoints == 0) {\n            return 0;\n        }\n\n        // First check most recent balance\n        if (checkpoints[account][nCheckpoints - 1].fromBlock \u003c= blockNumber) {\n            return checkpoints[account][nCheckpoints - 1].votes;\n        }\n\n        // Next check implicit zero balance\n        if (checkpoints[account][0].fromBlock \u003e blockNumber) {\n            return 0;\n        }\n\n        uint32 lower = 0;\n        uint32 upper = nCheckpoints - 1;\n        while (upper \u003e lower) {\n            uint32 center = upper - (upper - lower) / 2; // ceil, avoiding overflow\n            Checkpoint memory cp = checkpoints[account][center];\n            if (cp.fromBlock == blockNumber) {\n                return cp.votes;\n            } else if (cp.fromBlock \u003c blockNumber) {\n                lower = center;\n            } else {\n                upper = center - 1;\n            }\n        }\n        return checkpoints[account][lower].votes;\n    }\n\n    function _delegate(address delegator, address delegatee) internal {\n        address currentDelegate = delegates[delegator];\n        uint256 delegatorBalance = balances[delegator];\n        delegates[delegator] = delegatee;\n\n        emit DelegateChanged(delegator, currentDelegate, delegatee);\n\n        _moveDelegates(currentDelegate, delegatee, delegatorBalance);\n    }\n\n    function _transfer(\n        address src,\n        address dst,\n        uint256 amount\n    ) internal {\n        require(src != address(0), \"SENDER_ZERO_ADDR\");\n        require(dst != address(0), \"RECEIVER_ZERO_ADDR\");\n        require(dst != address(this), \"SEND_TO_TOKEN_CONTRACT\");\n\n        balances[src] = balances[src].sub(amount, \"TRANSFER_EXCEED_BALANCE\");\n        balances[dst] = balances[dst].add(amount);\n        emit Transfer(src, dst, amount);\n\n        _moveDelegates(delegates[src], delegates[dst], amount);\n    }\n\n    function _approve(\n        address src,\n        address dst,\n        uint256 amount\n    ) internal virtual {\n        require(src != address(0), \"OWNER_ZERO_ADDR\");\n        require(dst != address(0), \"SPENDER_ZERO_ADDR\");\n\n        allowances[src][dst] = amount;\n        emit Approval(src, dst, amount);\n    }\n\n    function _moveDelegates(\n        address srcRep,\n        address dstRep,\n        uint256 amount\n    ) internal {\n        if (srcRep != dstRep \u0026\u0026 amount \u003e 0) {\n            if (srcRep != address(0)) {\n                uint32 srcRepNum = numCheckpoints[srcRep];\n                uint256 srcRepOld = srcRepNum \u003e 0 ? checkpoints[srcRep][srcRepNum - 1].votes : 0;\n                uint256 srcRepNew = srcRepOld.sub(amount);\n                _writeCheckpoint(srcRep, srcRepNum, srcRepOld, srcRepNew);\n            }\n\n            if (dstRep != address(0)) {\n                uint32 dstRepNum = numCheckpoints[dstRep];\n                uint256 dstRepOld = dstRepNum \u003e 0 ? checkpoints[dstRep][dstRepNum - 1].votes : 0;\n                uint256 dstRepNew = dstRepOld.add(amount);\n                _writeCheckpoint(dstRep, dstRepNum, dstRepOld, dstRepNew);\n            }\n        }\n    }\n\n    function _writeCheckpoint(\n        address delegatee,\n        uint32 nCheckpoints,\n        uint256 oldVotes,\n        uint256 newVotes\n    ) internal {\n        uint32 blockNumber = safe32(block.number, \"BLOCK_NUM_EXCEED_32_BITS\");\n\n        if (\n            nCheckpoints \u003e 0 \u0026\u0026 checkpoints[delegatee][nCheckpoints - 1].fromBlock == blockNumber\n        ) {\n            checkpoints[delegatee][nCheckpoints - 1].votes = newVotes;\n        } else {\n            checkpoints[delegatee][nCheckpoints] = Checkpoint(blockNumber, newVotes);\n            numCheckpoints[delegatee] = nCheckpoints + 1;\n        }\n\n        emit DelegateVotesChanged(delegatee, oldVotes, newVotes);\n    }\n\n    function safe32(uint256 n, string memory errorMessage) internal pure returns (uint32) {\n        require(n \u003c 2**32, errorMessage);\n        return uint32(n);\n    }\n\n    function getChainId() internal pure returns (uint256) {\n        uint256 chainId;\n        assembly {\n            chainId := chainid()\n        }\n        return chainId;\n    }\n\n    function initiateConfigChanges(\n        uint256 _emissionRateMultiplierNumerator,\n        uint256 _terminalInflationRateNumerator,\n        address _liquidityIncentivesRecipient,\n        bool _isBurningAllowed\n    ) external override onlyGovernance {\n        require(_liquidityIncentivesRecipient != address(0), \"ZERO_ADDRESS\");\n        pendingEmissionRateMultiplierNumerator = _emissionRateMultiplierNumerator;\n        pendingTerminalInflationRateNumerator = _terminalInflationRateNumerator;\n        pendingLiquidityIncentivesRecipient = _liquidityIncentivesRecipient;\n        pendingIsBurningAllowed = _isBurningAllowed;\n        emit PendingConfigChanges(\n            _emissionRateMultiplierNumerator,\n            _terminalInflationRateNumerator,\n            _liquidityIncentivesRecipient,\n            _isBurningAllowed\n        );\n        configChangesInitiated = block.timestamp;\n    }\n\n    function applyConfigChanges() external override {\n        require(configChangesInitiated != 0, \"UNINITIATED_CONFIG_CHANGES\");\n        require(\n            block.timestamp \u003e configChangesInitiated + CONFIG_CHANGES_TIME_LOCK,\n            \"TIMELOCK_IS_NOT_OVER\"\n        );\n\n        _mintLiquidityEmissions(); // We must settle the pending liquidity emissions first, to make sure the weeks in the past follow the old configs\n\n        emissionRateMultiplierNumerator = pendingEmissionRateMultiplierNumerator;\n        terminalInflationRateNumerator = pendingTerminalInflationRateNumerator;\n        liquidityIncentivesRecipient = pendingLiquidityIncentivesRecipient;\n        isBurningAllowed = pendingIsBurningAllowed;\n        configChangesInitiated = 0;\n        emit ConfigsChanged(\n            emissionRateMultiplierNumerator,\n            terminalInflationRateNumerator,\n            liquidityIncentivesRecipient,\n            isBurningAllowed\n        );\n    }\n\n    function claimLiquidityEmissions() external override returns (uint256 totalEmissions) {\n        require(msg.sender == liquidityIncentivesRecipient, \"NOT_INCENTIVES_RECIPIENT\");\n        totalEmissions = _mintLiquidityEmissions();\n    }\n\n    function _mintLiquidityEmissions() internal returns (uint256 totalEmissions) {\n        uint256 _currentWeek = _getCurrentWeek();\n        if (_currentWeek \u003c= lastWeekEmissionSent) {\n            return 0;\n        }\n        for (uint256 i = lastWeekEmissionSent + 1; i \u003c= _currentWeek; i++) {\n            if (i \u003c= 259) {\n                lastWeeklyEmission = lastWeeklyEmission.mul(emissionRateMultiplierNumerator).div(\n                    CONFIG_DENOMINATOR\n                );\n            } else {\n                lastWeeklyEmission = totalSupply.mul(terminalInflationRateNumerator).div(\n                    CONFIG_DENOMINATOR\n                );\n            }\n            _mint(liquidityIncentivesRecipient, lastWeeklyEmission);\n            totalEmissions = totalEmissions.add(lastWeeklyEmission);\n        }\n        lastWeekEmissionSent = _currentWeek;\n    }\n\n    // get current 1-indexed week id\n    function _getCurrentWeek() internal view returns (uint256 weekId) {\n        weekId = (block.timestamp - startTime) / (7 days) + 1;\n    }\n\n    function _mint(address account, uint256 amount) internal {\n        require(account != address(0), \"MINT_TO_ZERO_ADDR\");\n\n        totalSupply = totalSupply.add(amount);\n        balances[account] = balances[account].add(amount);\n        emit Transfer(address(0), account, amount);\n    }\n\n    function _burn(address account, uint256 amount) internal {\n        require(account != address(0), \"BURN_FROM_ZERO_ADDRESS\");\n\n        uint256 accountBalance = balances[account];\n        require(accountBalance \u003e= amount, \"BURN_EXCEED_BALANCE\");\n        balances[account] = accountBalance.sub(amount);\n        totalSupply = totalSupply.sub(amount);\n\n        emit Transfer(account, address(0), amount);\n    }\n}\n"},"Permissions.sol":{"content":"// SPDX-License-Identifier: MIT\n/*\n * MIT License\n * ===========\n *\n * Permission is hereby granted, free of charge, to any person obtaining a copy\n * of this software and associated documentation files (the \"Software\"), to deal\n * in the Software without restriction, including without limitation the rights\n * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell\n * copies of the Software, and to permit persons to whom the Software is\n * furnished to do so, subject to the following conditions:\n *\n * The above copyright notice and this permission notice shall be included in all\n * copies or substantial portions of the Software.\n *\n * THE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR\n * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,\n * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE\n * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER\n * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,\n * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE\n */\npragma solidity 0.7.6;\n\nimport \"./IERC20.sol\";\n\nabstract contract Permissions {\n    address public governance;\n    address public pendingGovernance;\n    address internal initializer;\n\n    event GovernanceClaimed(address newGovernance, address previousGovernance);\n\n    event TransferGovernancePending(address pendingGovernance);\n\n    constructor(address _governance) {\n        require(_governance != address(0), \"ZERO_ADDRESS\");\n        initializer = msg.sender;\n        governance = _governance;\n    }\n\n    modifier initialized() {\n        require(initializer == address(0), \"NOT_INITIALIZED\");\n        _;\n    }\n\n    modifier onlyGovernance() {\n        require(msg.sender == governance, \"ONLY_GOVERNANCE\");\n        _;\n    }\n\n    /**\n     * @dev Allows the pendingGovernance address to finalize the change governance process.\n     */\n    function claimGovernance() public {\n        require(pendingGovernance == msg.sender, \"WRONG_GOVERNANCE\");\n        emit GovernanceClaimed(pendingGovernance, governance);\n        governance = pendingGovernance;\n        pendingGovernance = address(0);\n    }\n\n    /**\n     * @dev Allows the current governance to set the pendingGovernance address.\n     * @param _governance The address to transfer ownership to.\n     */\n    function transferGovernance(address _governance) public onlyGovernance {\n        require(_governance != address(0), \"ZERO_ADDRESS\");\n        pendingGovernance = _governance;\n\n        emit TransferGovernancePending(pendingGovernance);\n    }\n}\n"},"SafeERC20.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity \u003e=0.6.0 \u003c0.8.0;\n\nimport \"./IERC20.sol\";\nimport \"./SafeMath.sol\";\nimport \"./Address.sol\";\n\n/**\n * @title SafeERC20\n * @dev Wrappers around ERC20 operations that throw on failure (when the token\n * contract returns false). Tokens that return no value (and instead revert or\n * throw on failure) are also supported, non-reverting calls are assumed to be\n * successful.\n * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,\n * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.\n */\nlibrary SafeERC20 {\n    using SafeMath for uint256;\n    using Address for address;\n\n    function safeTransfer(IERC20 token, address to, uint256 value) internal {\n        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));\n    }\n\n    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {\n        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));\n    }\n\n    /**\n     * @dev Deprecated. This function has issues similar to the ones found in\n     * {IERC20-approve}, and its usage is discouraged.\n     *\n     * Whenever possible, use {safeIncreaseAllowance} and\n     * {safeDecreaseAllowance} instead.\n     */\n    function safeApprove(IERC20 token, address spender, uint256 value) internal {\n        // safeApprove should only be called when setting an initial allowance,\n        // or when resetting it to zero. To increase and decrease it, use\n        // \u0027safeIncreaseAllowance\u0027 and \u0027safeDecreaseAllowance\u0027\n        // solhint-disable-next-line max-line-length\n        require((value == 0) || (token.allowance(address(this), spender) == 0),\n            \"SafeERC20: approve from non-zero to non-zero allowance\"\n        );\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));\n    }\n\n    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {\n        uint256 newAllowance = token.allowance(address(this), spender).add(value);\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n    }\n\n    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {\n        uint256 newAllowance = token.allowance(address(this), spender).sub(value, \"SafeERC20: decreased allowance below zero\");\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n    }\n\n    /**\n     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement\n     * on the return value: the return value is optional (but if data is returned, it must not be false).\n     * @param token The token targeted by the call.\n     * @param data The call data (encoded using abi.encode or one of its variants).\n     */\n    function _callOptionalReturn(IERC20 token, bytes memory data) private {\n        // We need to perform a low level call here, to bypass Solidity\u0027s return data size checking mechanism, since\n        // we\u0027re implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that\n        // the target address contains contract code and also asserts for success in the low-level call.\n\n        bytes memory returndata = address(token).functionCall(data, \"SafeERC20: low-level call failed\");\n        if (returndata.length \u003e 0) { // Return data is optional\n            // solhint-disable-next-line max-line-length\n            require(abi.decode(returndata, (bool)), \"SafeERC20: ERC20 operation did not succeed\");\n        }\n    }\n}\n"},"SafeMath.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity \u003e=0.6.0 \u003c0.8.0;\n\n/**\n * @dev Wrappers over Solidity\u0027s arithmetic operations with added overflow\n * checks.\n *\n * Arithmetic operations in Solidity wrap on overflow. This can easily result\n * in bugs, because programmers usually assume that an overflow raises an\n * error, which is the standard behavior in high level programming languages.\n * `SafeMath` restores this intuition by reverting the transaction when an\n * operation overflows.\n *\n * Using this library instead of the unchecked operations eliminates an entire\n * class of bugs, so it\u0027s recommended to use it always.\n */\nlibrary SafeMath {\n    /**\n     * @dev Returns the addition of two unsigned integers, with an overflow flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        uint256 c = a + b;\n        if (c \u003c a) return (false, 0);\n        return (true, c);\n    }\n\n    /**\n     * @dev Returns the substraction of two unsigned integers, with an overflow flag.\n     *\n     * _Available since v3.4._\n     */\n    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        if (b \u003e a) return (false, 0);\n        return (true, a - b);\n    }\n\n    /**\n     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        // Gas optimization: this is cheaper than requiring \u0027a\u0027 not being zero, but the\n        // benefit is lost if \u0027b\u0027 is also tested.\n        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522\n        if (a == 0) return (true, 0);\n        uint256 c = a * b;\n        if (c / a != b) return (false, 0);\n        return (true, c);\n    }\n\n    /**\n     * @dev Returns the division of two unsigned integers, with a division by zero flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        if (b == 0) return (false, 0);\n        return (true, a / b);\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        if (b == 0) return (false, 0);\n        return (true, a % b);\n    }\n\n    /**\n     * @dev Returns the addition of two unsigned integers, reverting on\n     * overflow.\n     *\n     * Counterpart to Solidity\u0027s `+` operator.\n     *\n     * Requirements:\n     *\n     * - Addition cannot overflow.\n     */\n    function add(uint256 a, uint256 b) internal pure returns (uint256) {\n        uint256 c = a + b;\n        require(c \u003e= a, \"SafeMath: addition overflow\");\n        return c;\n    }\n\n    /**\n     * @dev Returns the subtraction of two unsigned integers, reverting on\n     * overflow (when the result is negative).\n     *\n     * Counterpart to Solidity\u0027s `-` operator.\n     *\n     * Requirements:\n     *\n     * - Subtraction cannot overflow.\n     */\n    function sub(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b \u003c= a, \"SafeMath: subtraction overflow\");\n        return a - b;\n    }\n\n    /**\n     * @dev Returns the multiplication of two unsigned integers, reverting on\n     * overflow.\n     *\n     * Counterpart to Solidity\u0027s `*` operator.\n     *\n     * Requirements:\n     *\n     * - Multiplication cannot overflow.\n     */\n    function mul(uint256 a, uint256 b) internal pure returns (uint256) {\n        if (a == 0) return 0;\n        uint256 c = a * b;\n        require(c / a == b, \"SafeMath: multiplication overflow\");\n        return c;\n    }\n\n    /**\n     * @dev Returns the integer division of two unsigned integers, reverting on\n     * division by zero. The result is rounded towards zero.\n     *\n     * Counterpart to Solidity\u0027s `/` operator. Note: this function uses a\n     * `revert` opcode (which leaves remaining gas untouched) while Solidity\n     * uses an invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function div(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b \u003e 0, \"SafeMath: division by zero\");\n        return a / b;\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n     * reverting when dividing by zero.\n     *\n     * Counterpart to Solidity\u0027s `%` operator. This function uses a `revert`\n     * opcode (which leaves remaining gas untouched) while Solidity uses an\n     * invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function mod(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b \u003e 0, \"SafeMath: modulo by zero\");\n        return a % b;\n    }\n\n    /**\n     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on\n     * overflow (when the result is negative).\n     *\n     * CAUTION: This function is deprecated because it requires allocating memory for the error\n     * message unnecessarily. For custom revert reasons use {trySub}.\n     *\n     * Counterpart to Solidity\u0027s `-` operator.\n     *\n     * Requirements:\n     *\n     * - Subtraction cannot overflow.\n     */\n    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b \u003c= a, errorMessage);\n        return a - b;\n    }\n\n    /**\n     * @dev Returns the integer division of two unsigned integers, reverting with custom message on\n     * division by zero. The result is rounded towards zero.\n     *\n     * CAUTION: This function is deprecated because it requires allocating memory for the error\n     * message unnecessarily. For custom revert reasons use {tryDiv}.\n     *\n     * Counterpart to Solidity\u0027s `/` operator. Note: this function uses a\n     * `revert` opcode (which leaves remaining gas untouched) while Solidity\n     * uses an invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b \u003e 0, errorMessage);\n        return a / b;\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n     * reverting with custom message when dividing by zero.\n     *\n     * CAUTION: This function is deprecated because it requires allocating memory for the error\n     * message unnecessarily. For custom revert reasons use {tryMod}.\n     *\n     * Counterpart to Solidity\u0027s `%` operator. This function uses a `revert`\n     * opcode (which leaves remaining gas untouched) while Solidity uses an\n     * invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b \u003e 0, errorMessage);\n        return a % b;\n    }\n}\n"},"Withdrawable.sol":{"content":"// SPDX-License-Identifier: MIT\n/*\n * MIT License\n * ===========\n *\n * Permission is hereby granted, free of charge, to any person obtaining a copy\n * of this software and associated documentation files (the \"Software\"), to deal\n * in the Software without restriction, including without limitation the rights\n * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell\n * copies of the Software, and to permit persons to whom the Software is\n * furnished to do so, subject to the following conditions:\n *\n * The above copyright notice and this permission notice shall be included in all\n * copies or substantial portions of the Software.\n *\n * THE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR\n * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,\n * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE\n * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER\n * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,\n * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE\n */\npragma solidity 0.7.6;\n\nimport \"./IERC20.sol\";\nimport \"./SafeERC20.sol\";\nimport \"./Permissions.sol\";\n\nabstract contract Withdrawable is Permissions {\n    using SafeERC20 for IERC20;\n\n    event EtherWithdraw(uint256 amount, address sendTo);\n    event TokenWithdraw(IERC20 token, uint256 amount, address sendTo);\n\n    /**\n     * @dev Allows governance to withdraw Ether in a Pendle contract\n     *      in case of accidental ETH transfer into the contract.\n     * @param amount The amount of Ether to withdraw.\n     * @param sendTo The recipient address.\n     */\n    function withdrawEther(uint256 amount, address payable sendTo) external onlyGovernance {\n        (bool success, ) = sendTo.call{value: amount}(\"\");\n        require(success, \"WITHDRAW_FAILED\");\n        emit EtherWithdraw(amount, sendTo);\n    }\n\n    /**\n     * @dev Allows governance to withdraw all IERC20 compatible tokens in a Pendle\n     *      contract in case of accidental token transfer into the contract.\n     * @param token IERC20 The address of the token contract.\n     * @param amount The amount of IERC20 tokens to withdraw.\n     * @param sendTo The recipient address.\n     */\n    function withdrawToken(\n        IERC20 token,\n        uint256 amount,\n        address sendTo\n    ) external onlyGovernance {\n        token.safeTransfer(sendTo, amount);\n        emit TokenWithdraw(token, amount, sendTo);\n    }\n}\n"}}

/**
 *Submitted for verification at BscScan.com on 2023-06-26
*/

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

// OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)

// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

// OpenZeppelin Contracts v4.4.1 (proxy/utils/Initializable.sol)

// OpenZeppelin Contracts v4.4.1 (utils/Address.sol)

/**
 * @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
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        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");

        (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");
        require(isContract(target), "Address: call to non-contract");

        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResult(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) {
        require(isContract(target), "Address: static call to non-contract");

        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason 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 {
            // 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

                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

/**
 * @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 a proxied contract can't have 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.
 *
 * 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 initialize the implementation contract, you can either invoke the
 * initializer manually, or you can include a constructor to automatically mark it as initialized when it is deployed:
 *
 * [.hljs-theme-light.nopadding]
 * ```
 * /// @custom:oz-upgrades-unsafe-allow constructor
 * constructor() initializer {}
 * ```
 * ====
 */
abstract contract Initializable {
    /**
     * @dev Indicates that the contract has been initialized.
     */
    bool private _initialized;

    /**
     * @dev Indicates that the contract is in the process of being initialized.
     */
    bool private _initializing;

    /**
     * @dev Modifier to protect an initializer function from being invoked twice.
     */
    modifier initializer() {
        // If the contract is initializing we ignore whether _initialized is set in order to support multiple
        // inheritance patterns, but we only do this in the context of a constructor, because in other contexts the
        // contract may have been reentered.
        require(_initializing ? _isConstructor() : !_initialized, "Initializable: contract is already initialized");

        bool isTopLevelCall = !_initializing;
        if (isTopLevelCall) {
            _initializing = true;
            _initialized = true;
        }

        _;

        if (isTopLevelCall) {
            _initializing = false;
        }
    }

    /**
     * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
     * {initializer} modifier, directly or indirectly.
     */
    modifier onlyInitializing() {
        require(_initializing, "Initializable: contract is not initializing");
        _;
    }

    function _isConstructor() private view returns (bool) {
        return !AddressUpgradeable.isContract(address(this));
    }
}

/**
 * @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 {
        __Context_init_unchained();
    }

    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;
    }
    uint256[50] private __gap;
}

/**
 * @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 {
        __Context_init_unchained();
        __Ownable_init_unchained();
    }

    function __Ownable_init_unchained() internal onlyInitializing {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual 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 {
        _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);
    }
    uint256[49] private __gap;
}

interface IERC20 {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint 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 (uint);

    function balanceOf(address owner) external view returns (uint);

    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);

    function transfer(address to, uint value) external returns (bool);

    function transferFrom(address from, address to, uint value) external returns (bool);
}

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;
        }
    }
}

/**
 * @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");
    }
}

/**
 * @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 ERC20;` 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));
    }

    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.

        // A Solidity high level call has three parts:
        //  1. The target address is checked to verify it contains contract code
        //  2. The call itself is made, and success asserted
        //  3. The return value is decoded, which in turn checks the size of the returned data.
        // solhint-disable-next-line max-line-length
        require(address(token).isContract(), "SafeERC20: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = address(token).call(data);
        require(success, "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");
        }
    }
}

/// @title Handle authorizations in dex platform
/// @notice Explain to an end user what this does
/// @dev Explain to a developer any extra details
contract TokenApprove is OwnableUpgradeable {
  using SafeERC20 for IERC20;

  address public tokenApproveProxy;

  function initialize(address _tokenApproveProxy) public initializer {
    __Ownable_init();
    tokenApproveProxy = _tokenApproveProxy;
  }

  //-------------------------------
  //------- Events ----------------
  //-------------------------------

  event ProxyUpdate(address indexed oldProxy, address indexed newProxy);

  //-------------------------------
  //------- Modifier --------------
  //-------------------------------

  //--------------------------------
  //------- Internal Functions -----
  //--------------------------------

  //---------------------------------
  //------- Admin functions ---------
  //---------------------------------

  function setApproveProxy(address _newTokenApproveProxy) external onlyOwner {
    tokenApproveProxy = _newTokenApproveProxy;
    emit ProxyUpdate(tokenApproveProxy, _newTokenApproveProxy);
  }

  //---------------------------------
  //-------  Users Functions --------
  //---------------------------------

  function claimTokens(
    address _token,
    address _who,
    address _dest,
    uint256 _amount
  ) external {
    require(msg.sender == tokenApproveProxy, "TokenApprove: Access restricted");
    if (_amount > 0) {
      IERC20(_token).safeTransferFrom(_who, _dest, _amount);
    }
  }
}