pragma solidity 0.4.18;

// File: contracts/FeeBurnerInterface.sol

interface FeeBurnerInterface {
    function handleFees (uint tradeWeiAmount, address reserve, address wallet) public returns(bool);
}

// File: contracts/ERC20Interface.sol

// https://github.com/ethereum/EIPs/issues/20
interface ERC20 {
    function totalSupply() public view returns (uint supply);
    function balanceOf(address _owner) public view returns (uint balance);
    function transfer(address _to, uint _value) public returns (bool success);
    function transferFrom(address _from, address _to, uint _value) public returns (bool success);
    function approve(address _spender, uint _value) public returns (bool success);
    function allowance(address _owner, address _spender) public view returns (uint remaining);
    function decimals() public view returns(uint digits);
    event Approval(address indexed _owner, address indexed _spender, uint _value);
}

// File: contracts/Utils.sol

/// @title Kyber constants contract
contract Utils {

    ERC20 constant internal ETH_TOKEN_ADDRESS = ERC20(0x00eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee);
    uint  constant internal PRECISION = (10**18);
    uint  constant internal MAX_QTY   = (10**28); // 10B tokens
    uint  constant internal MAX_RATE  = (PRECISION * 10**6); // up to 1M tokens per ETH
    uint  constant internal MAX_DECIMALS = 18;
    uint  constant internal ETH_DECIMALS = 18;
    mapping(address=>uint) internal decimals;

    function setDecimals(ERC20 token) internal {
        if (token == ETH_TOKEN_ADDRESS) decimals[token] = ETH_DECIMALS;
        else decimals[token] = token.decimals();
    }

    function getDecimals(ERC20 token) internal view returns(uint) {
        if (token == ETH_TOKEN_ADDRESS) return ETH_DECIMALS; // save storage access
        uint tokenDecimals = decimals[token];
        // technically, there might be token with decimals 0
        // moreover, very possible that old tokens have decimals 0
        // these tokens will just have higher gas fees.
        if(tokenDecimals == 0) return token.decimals();

        return tokenDecimals;
    }

    function calcDstQty(uint srcQty, uint srcDecimals, uint dstDecimals, uint rate) internal pure returns(uint) {
        require(srcQty <= MAX_QTY);
        require(rate <= MAX_RATE);

        if (dstDecimals >= srcDecimals) {
            require((dstDecimals - srcDecimals) <= MAX_DECIMALS);
            return (srcQty * rate * (10**(dstDecimals - srcDecimals))) / PRECISION;
        } else {
            require((srcDecimals - dstDecimals) <= MAX_DECIMALS);
            return (srcQty * rate) / (PRECISION * (10**(srcDecimals - dstDecimals)));
        }
    }

    function calcSrcQty(uint dstQty, uint srcDecimals, uint dstDecimals, uint rate) internal pure returns(uint) {
        require(dstQty <= MAX_QTY);
        require(rate <= MAX_RATE);
        
        //source quantity is rounded up. to avoid dest quantity being too low.
        uint numerator;
        uint denominator;
        if (srcDecimals >= dstDecimals) {
            require((srcDecimals - dstDecimals) <= MAX_DECIMALS);
            numerator = (PRECISION * dstQty * (10**(srcDecimals - dstDecimals)));
            denominator = rate;
        } else {
            require((dstDecimals - srcDecimals) <= MAX_DECIMALS);
            numerator = (PRECISION * dstQty);
            denominator = (rate * (10**(dstDecimals - srcDecimals)));
        }
        return (numerator + denominator - 1) / denominator; //avoid rounding down errors
    }
}

// File: contracts/PermissionGroups.sol

contract PermissionGroups {

    address public admin;
    address public pendingAdmin;
    mapping(address=>bool) internal operators;
    mapping(address=>bool) internal alerters;
    address[] internal operatorsGroup;
    address[] internal alertersGroup;
    uint constant internal MAX_GROUP_SIZE = 50;

    function PermissionGroups() public {
        admin = msg.sender;
    }

    modifier onlyAdmin() {
        require(msg.sender == admin);
        _;
    }

    modifier onlyOperator() {
        require(operators[msg.sender]);
        _;
    }

    modifier onlyAlerter() {
        require(alerters[msg.sender]);
        _;
    }

    function getOperators () external view returns(address[]) {
        return operatorsGroup;
    }

    function getAlerters () external view returns(address[]) {
        return alertersGroup;
    }

    event TransferAdminPending(address pendingAdmin);

    /**
     * @dev Allows the current admin to set the pendingAdmin address.
     * @param newAdmin The address to transfer ownership to.
     */
    function transferAdmin(address newAdmin) public onlyAdmin {
        require(newAdmin != address(0));
        TransferAdminPending(pendingAdmin);
        pendingAdmin = newAdmin;
    }

    /**
     * @dev Allows the current admin to set the admin in one tx. Useful initial deployment.
     * @param newAdmin The address to transfer ownership to.
     */
    function transferAdminQuickly(address newAdmin) public onlyAdmin {
        require(newAdmin != address(0));
        TransferAdminPending(newAdmin);
        AdminClaimed(newAdmin, admin);
        admin = newAdmin;
    }

    event AdminClaimed( address newAdmin, address previousAdmin);

    /**
     * @dev Allows the pendingAdmin address to finalize the change admin process.
     */
    function claimAdmin() public {
        require(pendingAdmin == msg.sender);
        AdminClaimed(pendingAdmin, admin);
        admin = pendingAdmin;
        pendingAdmin = address(0);
    }

    event AlerterAdded (address newAlerter, bool isAdd);

    function addAlerter(address newAlerter) public onlyAdmin {
        require(!alerters[newAlerter]); // prevent duplicates.
        require(alertersGroup.length < MAX_GROUP_SIZE);

        AlerterAdded(newAlerter, true);
        alerters[newAlerter] = true;
        alertersGroup.push(newAlerter);
    }

    function removeAlerter (address alerter) public onlyAdmin {
        require(alerters[alerter]);
        alerters[alerter] = false;

        for (uint i = 0; i < alertersGroup.length; ++i) {
            if (alertersGroup[i] == alerter) {
                alertersGroup[i] = alertersGroup[alertersGroup.length - 1];
                alertersGroup.length--;
                AlerterAdded(alerter, false);
                break;
            }
        }
    }

    event OperatorAdded(address newOperator, bool isAdd);

    function addOperator(address newOperator) public onlyAdmin {
        require(!operators[newOperator]); // prevent duplicates.
        require(operatorsGroup.length < MAX_GROUP_SIZE);

        OperatorAdded(newOperator, true);
        operators[newOperator] = true;
        operatorsGroup.push(newOperator);
    }

    function removeOperator (address operator) public onlyAdmin {
        require(operators[operator]);
        operators[operator] = false;

        for (uint i = 0; i < operatorsGroup.length; ++i) {
            if (operatorsGroup[i] == operator) {
                operatorsGroup[i] = operatorsGroup[operatorsGroup.length - 1];
                operatorsGroup.length -= 1;
                OperatorAdded(operator, false);
                break;
            }
        }
    }
}

// File: contracts/Withdrawable.sol

/**
 * @title Contracts that should be able to recover tokens or ethers
 * @author Ilan Doron
 * @dev This allows to recover any tokens or Ethers received in a contract.
 * This will prevent any accidental loss of tokens.
 */
contract Withdrawable is PermissionGroups {

    event TokenWithdraw(ERC20 token, uint amount, address sendTo);

    /**
     * @dev Withdraw all ERC20 compatible tokens
     * @param token ERC20 The address of the token contract
     */
    function withdrawToken(ERC20 token, uint amount, address sendTo) external onlyAdmin {
        require(token.transfer(sendTo, amount));
        TokenWithdraw(token, amount, sendTo);
    }

    event EtherWithdraw(uint amount, address sendTo);

    /**
     * @dev Withdraw Ethers
     */
    function withdrawEther(uint amount, address sendTo) external onlyAdmin {
        sendTo.transfer(amount);
        EtherWithdraw(amount, sendTo);
    }
}

// File: contracts/FeeBurner.sol

interface BurnableToken {
    function transferFrom(address _from, address _to, uint _value) public returns (bool);
    function burnFrom(address _from, uint256 _value) public returns (bool);
}


contract FeeBurner is Withdrawable, FeeBurnerInterface, Utils {

    mapping(address=>uint) public reserveFeesInBps;
    mapping(address=>address) public reserveKNCWallet; //wallet holding knc per reserve. from here burn and send fees.
    mapping(address=>uint) public walletFeesInBps; // wallet that is the source of tx is entitled so some fees.
    mapping(address=>uint) public reserveFeeToBurn;
    mapping(address=>uint) public feePayedPerReserve; // track burned fees and sent wallet fees per reserve.
    mapping(address=>mapping(address=>uint)) public reserveFeeToWallet;
    address public taxWallet;
    uint public taxFeeBps = 0; // burned fees are taxed. % out of burned fees.

    BurnableToken public knc;
    address public kyberNetwork;
    uint public kncPerETHRate = 300;

    function FeeBurner(address _admin, BurnableToken kncToken, address _kyberNetwork) public {
        require(_admin != address(0));
        require(kncToken != address(0));
        require(_kyberNetwork != address(0));
        kyberNetwork = _kyberNetwork;
        admin = _admin;
        knc = kncToken;
    }

    event ReserveDataSet(address reserve, uint feeInBps, address kncWallet);
    function setReserveData(address reserve, uint feesInBps, address kncWallet) public onlyAdmin {
        require(feesInBps < 100); // make sure it is always < 1%
        require(kncWallet != address(0));
        reserveFeesInBps[reserve] = feesInBps;
        reserveKNCWallet[reserve] = kncWallet;
        ReserveDataSet(reserve, feesInBps, kncWallet);
    }

    event WalletFeesSet(address wallet, uint feesInBps);
    function setWalletFees(address wallet, uint feesInBps) public onlyAdmin {
        require(feesInBps < 10000); // under 100%
        walletFeesInBps[wallet] = feesInBps;
        WalletFeesSet(wallet, feesInBps);
    }

    event TaxFeesSet(uint feesInBps);
    function setTaxInBps(uint _taxFeeBps) public onlyAdmin {
        require(_taxFeeBps < 10000); // under 100%
        taxFeeBps = _taxFeeBps;
        TaxFeesSet(_taxFeeBps);
    }

    event TaxWalletSet(address taxWallet);
    function setTaxWallet(address _taxWallet) public onlyAdmin {
        require(_taxWallet != address(0));
        taxWallet = _taxWallet;
        TaxWalletSet(_taxWallet);
    }

    function setKNCRate(uint rate) public onlyAdmin {
        require(rate <= MAX_RATE);
        kncPerETHRate = rate;
    }

    event AssignFeeToWallet(address reserve, address wallet, uint walletFee);
    event AssignBurnFees(address reserve, uint burnFee);

    function handleFees(uint tradeWeiAmount, address reserve, address wallet) public returns(bool) {
        require(msg.sender == kyberNetwork);
        require(tradeWeiAmount <= MAX_QTY);
        require(kncPerETHRate <= MAX_RATE);

        uint kncAmount = tradeWeiAmount * kncPerETHRate;
        uint fee = kncAmount * reserveFeesInBps[reserve] / 10000;

        uint walletFee = fee * walletFeesInBps[wallet] / 10000;
        require(fee >= walletFee);
        uint feeToBurn = fee - walletFee;

        if (walletFee > 0) {
            reserveFeeToWallet[reserve][wallet] += walletFee;
            AssignFeeToWallet(reserve, wallet, walletFee);
        }

        if (feeToBurn > 0) {
            AssignBurnFees(reserve, feeToBurn);
            reserveFeeToBurn[reserve] += feeToBurn;
        }

        return true;
    }

    event BurnAssignedFees(address indexed reserve, address sender, uint quantity);

    event SendTaxFee(address indexed reserve, address sender, address taxWallet, uint quantity);

    // this function is callable by anyone
    function burnReserveFees(address reserve) public {
        uint burnAmount = reserveFeeToBurn[reserve];
        uint taxToSend = 0;
        require(burnAmount > 2);
        reserveFeeToBurn[reserve] = 1; // leave 1 twei to avoid spikes in gas fee
        if (taxWallet != address(0) && taxFeeBps != 0) {
            taxToSend = (burnAmount - 1) * taxFeeBps / 10000;
            require(burnAmount - 1 > taxToSend);
            burnAmount -= taxToSend;
            if (taxToSend > 0) {
                require(knc.transferFrom(reserveKNCWallet[reserve], taxWallet, taxToSend));
                SendTaxFee(reserve, msg.sender, taxWallet, taxToSend);
            }
        }
        require(knc.burnFrom(reserveKNCWallet[reserve], burnAmount - 1));

        //update reserve "payments" so far
        feePayedPerReserve[reserve] += (taxToSend + burnAmount - 1);

        BurnAssignedFees(reserve, msg.sender, (burnAmount - 1));
    }

    event SendWalletFees(address indexed wallet, address reserve, address sender);

    // this function is callable by anyone
    function sendFeeToWallet(address wallet, address reserve) public {
        uint feeAmount = reserveFeeToWallet[reserve][wallet];
        require(feeAmount > 1);
        reserveFeeToWallet[reserve][wallet] = 1; // leave 1 twei to avoid spikes in gas fee
        require(knc.transferFrom(reserveKNCWallet[reserve], wallet, feeAmount - 1));

        feePayedPerReserve[reserve] += (feeAmount - 1);
        SendWalletFees(wallet, reserve, msg.sender);
    }
}

pragma solidity ^0.4.13;

library SafeMath {
  function mul(uint256 a, uint256 b) internal constant returns (uint256) {
    uint256 c = a * b;
    assert(a == 0 || c / a == b);
    return c;
  }

  function div(uint256 a, uint256 b) internal constant 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 constant returns (uint256) {
    assert(b <= a);
    return a - b;
  }

  function add(uint256 a, uint256 b) internal constant returns (uint256) {
    uint256 c = a + b;
    assert(c >= a);
    return c;
  }
}

contract Ownable {
  address public owner;


  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  function Ownable() {
    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) onlyOwner {
    if (newOwner != address(0)) {
      owner = newOwner;
    }
  }

}



contract ERC20Basic {
  uint256 public totalSupply;
  function balanceOf(address who) constant returns (uint256);
  function transfer(address to, uint256 value) returns (bool);
  
  // KYBER-NOTE! code changed to comply with ERC20 standard
  event Transfer(address indexed _from, address indexed _to, uint _value);
  //event Transfer(address indexed from, address indexed to, uint256 value);
}

contract BasicToken is ERC20Basic {
  using SafeMath for uint256;

  mapping(address => uint256) balances;

  /**
  * @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, uint256 _value) returns (bool) {
    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    Transfer(msg.sender, _to, _value);
    return true;
  }

  /**
  * @dev Gets the balance of the specified address.
  * @param _owner The address to query the the balance of. 
  * @return An uint256 representing the amount owned by the passed address.
  */
  function balanceOf(address _owner) constant returns (uint256 balance) {
    return balances[_owner];
  }

}

contract ERC20 is ERC20Basic {
  function allowance(address owner, address spender) constant returns (uint256);
  function transferFrom(address from, address to, uint256 value) returns (bool);
  function approve(address spender, uint256 value) returns (bool);
  
  // KYBER-NOTE! code changed to comply with ERC20 standard
  event Approval(address indexed _owner, address indexed _spender, uint _value);
  //event Approval(address indexed owner, address indexed spender, uint256 value);
}

contract StandardToken is ERC20, BasicToken {

  mapping (address => mapping (address => uint256)) allowed;


  /**
   * @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 uint256 the amout of tokens to be transfered
   */
  function transferFrom(address _from, address _to, uint256 _value) returns (bool) {
    var _allowance = allowed[_from][msg.sender];

    // Check is not needed because sub(_allowance, _value) will already throw if this condition is not met
    // require (_value <= _allowance);

    // KYBER-NOTE! code changed to comply with ERC20 standard
    balances[_from] = balances[_from].sub(_value);
    balances[_to] = balances[_to].add(_value);
    //balances[_from] = balances[_from].sub(_value); // this was removed
    allowed[_from][msg.sender] = _allowance.sub(_value);
    Transfer(_from, _to, _value);
    return true;
  }

  /**
   * @dev Aprove 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, uint256 _value) returns (bool) {

    // 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);
    return true;
  }

  /**
   * @dev Function to check the amount of tokens that 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 uint256 specifing the amount of tokens still avaible for the spender.
   */
  function allowance(address _owner, address _spender) constant returns (uint256 remaining) {
    return allowed[_owner][_spender];
  }

}

contract KyberNetworkCrystal is StandardToken, Ownable {
    string  public  constant name = "Kyber Network Crystal";
    string  public  constant symbol = "KNC";
    uint    public  constant decimals = 18;

    uint    public  saleStartTime;
    uint    public  saleEndTime;

    address public  tokenSaleContract;

    modifier onlyWhenTransferEnabled() {
        if( now <= saleEndTime && now >= saleStartTime ) {
            require( msg.sender == tokenSaleContract );
        }
        _;
    }

    modifier validDestination( address to ) {
        require(to != address(0x0));
        require(to != address(this) );
        _;
    }

    function KyberNetworkCrystal( uint tokenTotalAmount, uint startTime, uint endTime, address admin ) {
        // Mint all tokens. Then disable minting forever.
        balances[msg.sender] = tokenTotalAmount;
        totalSupply = tokenTotalAmount;
        Transfer(address(0x0), msg.sender, tokenTotalAmount);

        saleStartTime = startTime;
        saleEndTime = endTime;

        tokenSaleContract = msg.sender;
        transferOwnership(admin); // admin could drain tokens that were sent here by mistake
    }

    function transfer(address _to, uint _value)
        onlyWhenTransferEnabled
        validDestination(_to)
        returns (bool) {
        return super.transfer(_to, _value);
    }

    function transferFrom(address _from, address _to, uint _value)
        onlyWhenTransferEnabled
        validDestination(_to)
        returns (bool) {
        return super.transferFrom(_from, _to, _value);
    }

    event Burn(address indexed _burner, uint _value);

    function burn(uint _value) onlyWhenTransferEnabled
        returns (bool){
        balances[msg.sender] = balances[msg.sender].sub(_value);
        totalSupply = totalSupply.sub(_value);
        Burn(msg.sender, _value);
        Transfer(msg.sender, address(0x0), _value);
        return true;
    }

    // save some gas by making only one contract call
    function burnFrom(address _from, uint256 _value) onlyWhenTransferEnabled
        returns (bool) {
        assert( transferFrom( _from, msg.sender, _value ) );
        return burn(_value);
    }

    function emergencyERC20Drain( ERC20 token, uint amount ) onlyOwner {
        token.transfer( owner, amount );
    }
}