contract Escapable is Owned {
    address public escapeHatchCaller;
    address public escapeHatchDestination;
    mapping (address=>bool) private escapeBlacklist; // Token contract addresses

    /// @notice The Constructor assigns the `escapeHatchDestination` and the
    ///  `escapeHatchCaller`
    /// @param _escapeHatchCaller The address of a trusted account or contract
    ///  to call `escapeHatch()` to send the ether in this contract to the
    ///  `escapeHatchDestination` it would be ideal that `escapeHatchCaller`
    ///  cannot move funds out of `escapeHatchDestination`
    /// @param _escapeHatchDestination The address of a safe location (usu a
    ///  Multisig) to send the ether held in this contract; if a neutral address
    ///  is required, the WHG Multisig is an option:
    ///  0x8Ff920020c8AD673661c8117f2855C384758C572 
    function Escapable(address _escapeHatchCaller, address _escapeHatchDestination) public {
        escapeHatchCaller = _escapeHatchCaller;
        escapeHatchDestination = _escapeHatchDestination;
    }

    /// @dev The addresses preassigned as `escapeHatchCaller` or `owner`
    ///  are the only addresses that can call a function with this modifier
    modifier onlyEscapeHatchCallerOrOwner {
        require ((msg.sender == escapeHatchCaller)||(msg.sender == owner));
        _;
    }

    /// @notice Creates the blacklist of tokens that are not able to be taken
    ///  out of the contract; can only be done at the deployment, and the logic
    ///  to add to the blacklist will be in the constructor of a child contract
    /// @param _token the token contract address that is to be blacklisted 
    function blacklistEscapeToken(address _token) internal {
        escapeBlacklist[_token] = true;
        EscapeHatchBlackistedToken(_token);
    }

    /// @notice Checks to see if `_token` is in the blacklist of tokens
    /// @param _token the token address being queried
    /// @return False if `_token` is in the blacklist and can't be taken out of
    ///  the contract via the `escapeHatch()`
    function isTokenEscapable(address _token) constant public returns (bool) {
        return !escapeBlacklist[_token];
    }

    /// @notice The `escapeHatch()` should only be called as a last resort if a
    /// security issue is uncovered or something unexpected happened
    /// @param _token to transfer, use 0x0 for ether
    function escapeHatch(address _token) public onlyEscapeHatchCallerOrOwner {   
        require(escapeBlacklist[_token]==false);

        uint256 balance;

        /// @dev Logic for ether
        if (_token == 0x0) {
            balance = this.balance;
            escapeHatchDestination.transfer(balance);
            EscapeHatchCalled(_token, balance);
            return;
        }
        /// @dev Logic for tokens
        ERC20 token = ERC20(_token);
        balance = token.balanceOf(this);
        require(token.transfer(escapeHatchDestination, balance));
        EscapeHatchCalled(_token, balance);
    }

    /// @notice Changes the address assigned to call `escapeHatch()`
    /// @param _newEscapeHatchCaller The address of a trusted account or
    ///  contract to call `escapeHatch()` to send the value in this contract to
    ///  the `escapeHatchDestination`; it would be ideal that `escapeHatchCaller`
    ///  cannot move funds out of `escapeHatchDestination`
    function changeHatchEscapeCaller(address _newEscapeHatchCaller) public onlyEscapeHatchCallerOrOwner {
        escapeHatchCaller = _newEscapeHatchCaller;
    }

    event EscapeHatchBlackistedToken(address token);
    event EscapeHatchCalled(address token, uint amount);
}
/// @dev `Escapable` is a base level contract built off of the `Owned`
///  contract; it creates an escape hatch function that can be called in an
///  emergency that will allow designated addresses to send any ether or tokens
///  held in the contract to an `escapeHatchDestination` as long as they were
///  not blacklisted
function isTokenEscapable(address _token) constant public returns (bool) {
    return !escapeBlacklist[_token];
}

/// @notice Checks to see if `_token` is in the blacklist of tokens
/// @param _token the token address being queried
/// @return False if `_token` is in the blacklist and can't be taken out of
///  the contract via the `escapeHatch()`