pragma solidity ^0.4.21;


import '@daonomic/interfaces/contracts/ExternalToken.sol';
import '@daonomic/interfaces/contracts/TokenReceiver.sol';
import '../standard/NotifyingTokenImpl.sol';


contract ExternalTokenImpl is ExternalToken, NotifyingTokenImpl {
    modifier onlyMinter() {
        checkMinter();
        _;
    }

    function checkMinter() internal;

    function mint(address _to, uint256 _value, bytes _mintData) onlyMinter public returns (bool) {
        _mint(_to, _value, _mintData);
        emitTransferWithData(0x0, _to, _value, "");
        return true;
    }

    function mintAndCall(address _to, uint256 _value, bytes _mintData, bytes _data) onlyMinter public returns (bool) {
        _mint(_to, _value, _mintData);
        emitTransferWithData(0x0, _to, _value, _data);
        TokenReceiver(_to).onTokenTransfer(0x0, _value, _data);
        return true;
    }

    function _mint(address _to, uint256 _value, bytes _data) private {
        totalSupply = totalSupply.add(_value);
        balances[_to] = balances[_to].add(_value);
        emit Mint(_to, _value, _data);
    }

    function burn(uint256 _value, bytes _data) public {
        require(_value > 0);
        require(_value <= balances[msg.sender]);
        checkBurnData(_value, _data);

        address burner = msg.sender;
        balances[burner] = balances[burner].sub(_value);
        totalSupply = totalSupply.sub(_value);
        emit Burn(burner, _value, _data);
    }

    function checkBurnData(uint256 _value, bytes _data) internal {

    }
}