Contract Source Code:

/**
 *Submitted for verification at Etherscan.io on 2020-04-06
 */

// File: openzeppelin-solidity/contracts/token/ERC20/ERC20Basic.sol

pragma solidity ^0.4.24;

/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * See https://github.com/ethereum/EIPs/issues/179
 */
contract ERC20Basic {
    function totalSupply() public view returns (uint256);

    function balanceOf(address _who) public view returns (uint256);

    function transfer(address _to, uint256 _value) public returns (bool);

    event Transfer(address indexed from, address indexed to, uint256 value);
}

// File: openzeppelin-solidity/contracts/math/SafeMath.sol

pragma solidity ^0.4.24;

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {
    /**
     * @dev Multiplies two numbers, throws on overflow.
     */
    function mul(uint256 _a, uint256 _b) internal pure returns (uint256 c) {
        // Gas optimization: this is cheaper than asserting 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
        if (_a == 0) {
            return 0;
        }

        c = _a * _b;
        assert(c / _a == _b);
        return c;
    }

    /**
     * @dev Integer division of two numbers, truncating the quotient.
     */
    function div(uint256 _a, uint256 _b) internal pure returns (uint256) {
        // assert(_b > 0); // Solidity automatically throws when dividing by 0
        // uint256 c = _a / _b;
        // assert(_a == _b * c + _a % _b); // There is no case in which this doesn't hold
        return _a / _b;
    }

    /**
     * @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
     */
    function sub(uint256 _a, uint256 _b) internal pure returns (uint256) {
        assert(_b <= _a);
        return _a - _b;
    }

    /**
     * @dev Adds two numbers, throws on overflow.
     */
    function add(uint256 _a, uint256 _b) internal pure returns (uint256 c) {
        c = _a + _b;
        assert(c >= _a);
        return c;
    }
}

// File: openzeppelin-solidity/contracts/token/ERC20/BasicToken.sol

pragma solidity ^0.4.24;

/**
 * @title Basic token
 * @dev Basic version of StandardToken, with no allowances.
 */
contract BasicToken is ERC20Basic {
    using SafeMath for uint256;

    mapping(address => uint256) internal balances;

    uint256 internal totalSupply_;

    /**
     * @dev Total number of tokens in existence
     */
    function totalSupply() public view returns (uint256) {
        return totalSupply_;
    }

    /**
     * @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) public returns (bool) {
        require(_value <= balances[msg.sender]);
        require(_to != address(0));

        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(_value);
        emit 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) public view returns (uint256) {
        return balances[_owner];
    }
}

// File: openzeppelin-solidity/contracts/token/ERC20/BurnableToken.sol

pragma solidity ^0.4.24;

/**
 * @title Burnable Token
 * @dev Token that can be irreversibly burned (destroyed).
 */
contract BurnableToken is BasicToken {
    event Burn(address indexed burner, uint256 value);

    /**
     * @dev Burns a specific amount of tokens.
     * @param _value The amount of token to be burned.
     */
    function burn(uint256 _value) public {
        _burn(msg.sender, _value);
    }

    function _burn(address _who, uint256 _value) internal {
        require(_value <= balances[_who]);
        // no need to require value <= totalSupply, since that would imply the
        // sender's balance is greater than the totalSupply, which *should* be an assertion failure

        balances[_who] = balances[_who].sub(_value);
        totalSupply_ = totalSupply_.sub(_value);
        emit Burn(_who, _value);
        emit Transfer(_who, address(0), _value);
    }
}

// File: openzeppelin-solidity/contracts/token/ERC20/ERC20.sol

pragma solidity ^0.4.24;

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20 is ERC20Basic {
    function allowance(address _owner, address _spender)
        public
        view
        returns (uint256);

    function transferFrom(
        address _from,
        address _to,
        uint256 _value
    ) public returns (bool);

    function approve(address _spender, uint256 _value) public returns (bool);

    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
}

// File: openzeppelin-solidity/contracts/token/ERC20/StandardToken.sol

pragma solidity ^0.4.24;

/**
 * @title Standard ERC20 token
 *
 * @dev Implementation of the basic standard token.
 * https://github.com/ethereum/EIPs/issues/20
 * Based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
 */
contract StandardToken is ERC20, BasicToken {
    mapping(address => mapping(address => uint256)) internal 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 amount of tokens to be transferred
     */
    function transferFrom(
        address _from,
        address _to,
        uint256 _value
    ) public returns (bool) {
        require(_value <= balances[_from]);
        require(_value <= allowed[_from][msg.sender]);
        require(_to != address(0));

        balances[_from] = balances[_from].sub(_value);
        balances[_to] = balances[_to].add(_value);
        allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
        emit Transfer(_from, _to, _value);
        return true;
    }

    /**
     * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
     * Beware that changing an allowance with this method brings the risk that someone may use both the old
     * and the new allowance by unfortunate transaction ordering. One possible solution to mitigate this
     * race condition is to first reduce the spender's allowance to 0 and set the desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     * @param _spender The address which will spend the funds.
     * @param _value The amount of tokens to be spent.
     */
    function approve(address _spender, uint256 _value) public returns (bool) {
        allowed[msg.sender][_spender] = _value;
        emit 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 specifying the amount of tokens still available for the spender.
     */
    function allowance(address _owner, address _spender)
        public
        view
        returns (uint256)
    {
        return allowed[_owner][_spender];
    }

    /**
     * @dev Increase the amount of tokens that an owner allowed to a spender.
     * approve should be called when allowed[_spender] == 0. To increment
     * allowed value is better to use this function to avoid 2 calls (and wait until
     * the first transaction is mined)
     * From MonolithDAO Token.sol
     * @param _spender The address which will spend the funds.
     * @param _addedValue The amount of tokens to increase the allowance by.
     */
    function increaseApproval(address _spender, uint256 _addedValue)
        public
        returns (bool)
    {
        allowed[msg.sender][_spender] = (
            allowed[msg.sender][_spender].add(_addedValue)
        );
        emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
        return true;
    }

    /**
     * @dev Decrease the amount of tokens that an owner allowed to a spender.
     * approve should be called when allowed[_spender] == 0. To decrement
     * allowed value is better to use this function to avoid 2 calls (and wait until
     * the first transaction is mined)
     * From MonolithDAO Token.sol
     * @param _spender The address which will spend the funds.
     * @param _subtractedValue The amount of tokens to decrease the allowance by.
     */
    function decreaseApproval(address _spender, uint256 _subtractedValue)
        public
        returns (bool)
    {
        uint256 oldValue = allowed[msg.sender][_spender];
        if (_subtractedValue >= oldValue) {
            allowed[msg.sender][_spender] = 0;
        } else {
            allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
        }
        emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
        return true;
    }
}

// File: openzeppelin-solidity/contracts/ownership/Ownable.sol

pragma solidity ^0.4.24;

/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
    address public owner;

    event OwnershipRenounced(address indexed previousOwner);
    event OwnershipTransferred(
        address indexed previousOwner,
        address indexed newOwner
    );

    /**
     * @dev The Ownable constructor sets the original `owner` of the contract to the sender
     * account.
     */
    constructor() public {
        owner = msg.sender;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(msg.sender == owner);
        _;
    }

    /**
     * @dev Allows the current owner to relinquish control of the contract.
     * @notice Renouncing to ownership will leave the contract without an owner.
     * It will not be possible to call the functions with the `onlyOwner`
     * modifier anymore.
     */
    function renounceOwnership() public onlyOwner {
        emit OwnershipRenounced(owner);
        owner = address(0);
    }

    /**
     * @dev Allows the current owner to transfer control of the contract to a newOwner.
     * @param _newOwner The address to transfer ownership to.
     */
    function transferOwnership(address _newOwner) public onlyOwner {
        _transferOwnership(_newOwner);
    }

    /**
     * @dev Transfers control of the contract to a newOwner.
     * @param _newOwner The address to transfer ownership to.
     */
    function _transferOwnership(address _newOwner) internal {
        require(_newOwner != address(0));
        emit OwnershipTransferred(owner, _newOwner);
        owner = _newOwner;
    }
}

// File: openzeppelin-solidity/contracts/token/ERC20/MintableToken.sol

pragma solidity ^0.4.24;

/**
 * @title Mintable token
 * @dev Simple ERC20 Token example, with mintable token creation
 * Based on code by TokenMarketNet: https://github.com/TokenMarketNet/ico/blob/master/contracts/MintableToken.sol
 */
contract MintableToken is StandardToken, Ownable {
    event Mint(address indexed to, uint256 amount);
    event MintFinished();

    bool public mintingFinished = false;

    modifier canMint() {
        require(!mintingFinished);
        _;
    }

    modifier hasMintPermission() {
        require(msg.sender == owner);
        _;
    }

    /**
     * @dev Function to mint tokens
     * @param _to The address that will receive the minted tokens.
     * @param _amount The amount of tokens to mint.
     * @return A boolean that indicates if the operation was successful.
     */
    function mint(address _to, uint256 _amount)
        public
        hasMintPermission
        canMint
        returns (bool)
    {
        totalSupply_ = totalSupply_.add(_amount);
        balances[_to] = balances[_to].add(_amount);
        emit Mint(_to, _amount);
        emit Transfer(address(0), _to, _amount);
        return true;
    }

    /**
     * @dev Function to stop minting new tokens.
     * @return True if the operation was successful.
     */
    function finishMinting() public onlyOwner canMint returns (bool) {
        mintingFinished = true;
        emit MintFinished();
        return true;
    }
}

// File: openzeppelin-solidity/contracts/token/ERC20/DetailedERC20.sol

pragma solidity ^0.4.24;

/**
 * @title DetailedERC20 token
 * @dev The decimals are only for visualization purposes.
 * All the operations are done using the smallest and indivisible token unit,
 * just as on Ethereum all the operations are done in wei.
 */
contract DetailedERC20 is ERC20 {
    string public name;
    string public symbol;
    uint8 public decimals;

    constructor(
        string _name,
        string _symbol,
        uint8 _decimals
    ) public {
        name = _name;
        symbol = _symbol;
        decimals = _decimals;
    }
}

// File: openzeppelin-solidity/contracts/AddressUtils.sol

pragma solidity ^0.4.24;

/**
 * Utility library of inline functions on addresses
 */
library AddressUtils {
    /**
     * Returns whether the target address is a contract
     * @dev This function will return false if invoked during the constructor of a contract,
     * as the code is not actually created until after the constructor finishes.
     * @param _addr address to check
     * @return whether the target address is a contract
     */
    function isContract(address _addr) internal view returns (bool) {
        uint256 size;
        // XXX Currently there is no better way to check if there is a contract in an address
        // than to check the size of the code at that address.
        // See https://ethereum.stackexchange.com/a/14016/36603
        // for more details about how this works.
        // TODO Check this again before the Serenity release, because all addresses will be
        // contracts then.
        // solium-disable-next-line security/no-inline-assembly
        assembly {
            size := extcodesize(_addr)
        }
        return size > 0;
    }
}

// File: contracts/interfaces/ERC677.sol

pragma solidity 0.4.24;

contract ERC677 is ERC20 {
    event Transfer(
        address indexed from,
        address indexed to,
        uint256 value,
        bytes data
    );

    function transferAndCall(
        address,
        uint256,
        bytes
    ) external returns (bool);

    function increaseAllowance(address spender, uint256 addedValue)
        public
        returns (bool);

    function decreaseAllowance(address spender, uint256 subtractedValue)
        public
        returns (bool);
}

// File: contracts/interfaces/IBurnableMintableERC677Token.sol

pragma solidity 0.4.24;

contract IBurnableMintableERC677Token is ERC677 {
    function mint(address _to, uint256 _amount) public returns (bool);

    function burn(uint256 _value) public;

    function claimTokens(address _token, address _to) public;
}

// File: contracts/upgradeable_contracts/Sacrifice.sol

pragma solidity 0.4.24;

contract Sacrifice {
    constructor(address _recipient) public payable {
        selfdestruct(_recipient);
    }
}

// File: contracts/upgradeable_contracts/Claimable.sol

pragma solidity 0.4.24;

contract Claimable {
    bytes4 internal constant TRANSFER = 0xa9059cbb; // transfer(address,uint256)

    modifier validAddress(address _to) {
        require(_to != address(0));
        /* solcov ignore next */
        _;
    }

    function claimValues(address _token, address _to) internal {
        if (_token == address(0)) {
            claimNativeCoins(_to);
        } else {
            claimErc20Tokens(_token, _to);
        }
    }

    function claimNativeCoins(address _to) internal {
        uint256 value = address(this).balance;
        if (!_to.send(value)) {
            (new Sacrifice).value(value)(_to);
        }
    }

    function claimErc20Tokens(address _token, address _to) internal {
        ERC20Basic token = ERC20Basic(_token);
        uint256 balance = token.balanceOf(this);
        safeTransfer(_token, _to, balance);
    }

    function safeTransfer(
        address _token,
        address _to,
        uint256 _value
    ) internal {
        bytes memory returnData;
        bool returnDataResult;
        bytes memory callData = abi.encodeWithSelector(TRANSFER, _to, _value);
        assembly {
            let result := call(
                gas,
                _token,
                0x0,
                add(callData, 0x20),
                mload(callData),
                0,
                32
            )
            returnData := mload(0)
            returnDataResult := mload(0)

            switch result
                case 0 {
                    revert(0, 0)
                }
        }

        // Return data is optional
        if (returnData.length > 0) {
            require(returnDataResult);
        }
    }
}

// File: contracts/ERC677BridgeToken.sol

pragma solidity 0.4.24;

contract ERC677BridgeToken is
    IBurnableMintableERC677Token,
    DetailedERC20,
    BurnableToken,
    MintableToken,
    Claimable
{
    address public bridgeContract;

    event ContractFallbackCallFailed(address from, address to, uint256 value);

    constructor(
        string _name,
        string _symbol,
        uint8 _decimals
    ) public DetailedERC20(_name, _symbol, _decimals) {
        // solhint-disable-previous-line no-empty-blocks
    }

    function setBridgeContract(address _bridgeContract) external onlyOwner {
        require(AddressUtils.isContract(_bridgeContract));
        bridgeContract = _bridgeContract;
    }

    modifier validRecipient(address _recipient) {
        require(_recipient != address(0) && _recipient != address(this));
        /* solcov ignore next */
        _;
    }

    function transferAndCall(
        address _to,
        uint256 _value,
        bytes _data
    ) external validRecipient(_to) returns (bool) {
        require(superTransfer(_to, _value));
        emit Transfer(msg.sender, _to, _value, _data);

        if (AddressUtils.isContract(_to)) {
            require(contractFallback(msg.sender, _to, _value, _data));
        }
        return true;
    }

    function getTokenInterfacesVersion()
        external
        pure
        returns (
            uint64 major,
            uint64 minor,
            uint64 patch
        )
    {
        return (2, 2, 0);
    }

    function superTransfer(address _to, uint256 _value)
        internal
        returns (bool)
    {
        return super.transfer(_to, _value);
    }

    function transfer(address _to, uint256 _value) public returns (bool) {
        require(superTransfer(_to, _value));
        callAfterTransfer(msg.sender, _to, _value);
        return true;
    }

    function transferFrom(
        address _from,
        address _to,
        uint256 _value
    ) public returns (bool) {
        require(super.transferFrom(_from, _to, _value));
        callAfterTransfer(_from, _to, _value);
        return true;
    }

    function callAfterTransfer(
        address _from,
        address _to,
        uint256 _value
    ) internal {
        if (
            AddressUtils.isContract(_to) &&
            !contractFallback(_from, _to, _value, new bytes(0))
        ) {
            require(_to != bridgeContract);
            emit ContractFallbackCallFailed(_from, _to, _value);
        }
    }

    function contractFallback(
        address _from,
        address _to,
        uint256 _value,
        bytes _data
    ) private returns (bool) {
        return
            _to.call(
                abi.encodeWithSignature(
                    "onTokenTransfer(address,uint256,bytes)",
                    _from,
                    _value,
                    _data
                )
            );
    }

    function finishMinting() public returns (bool) {
        revert();
    }

    function renounceOwnership() public onlyOwner {
        revert();
    }

    function claimTokens(address _token, address _to)
        public
        onlyOwner
        validAddress(_to)
    {
        claimValues(_token, _to);
    }

    function increaseAllowance(address spender, uint256 addedValue)
        public
        returns (bool)
    {
        return super.increaseApproval(spender, addedValue);
    }

    function decreaseAllowance(address spender, uint256 subtractedValue)
        public
        returns (bool)
    {
        return super.decreaseApproval(spender, subtractedValue);
    }
}