pragma solidity ^0.4.18;


library SafeMath {
    function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {
        if (a == 0) {
            return 0;
        }
        c = a * b;
        assert(c / a == b);
        return c;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        assert(b <= a);
        return a - b;
    }

    function add(uint256 a, uint256 b) internal pure returns (uint256 c) {
        c = a + b;
        assert(c >= a);
        return c;
    }
}


contract Ownable {
    address public owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    function Ownable() public {
        owner = msg.sender;
    }

    modifier onlyOwner() {
        require(msg.sender == owner);
        _;
    }

    function transferOwnership(address newOwner) public onlyOwner {
        require(newOwner != address(0));
        OwnershipTransferred(owner, newOwner);
        owner = newOwner;
    }
}

contract Pausable is Ownable {
    event Pause();
    event Unpause();

    bool public paused = false;

    modifier whenNotPaused() {
        require(!paused);
        _;
    }

    modifier whenPaused() {
        require(paused);
        _;
    }

    function pause() onlyOwner whenNotPaused public {
        paused = true;
        Pause();
    }

    function unpause() onlyOwner whenPaused public {
        paused = false;
        Unpause();
    }
}

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);
}

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);
}

contract BasicToken is ERC20Basic {
    using SafeMath for uint256;
    mapping(address => uint256) balances;
    uint256 totalSupply_;

    function totalSupply() public view returns (uint256) {
        return totalSupply_;
    }

    function transfer(address _to, uint256 _value) public returns (bool) {
        require(_to != address(0));
        require(_value <= balances[msg.sender]);

        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(_value);
        Transfer(msg.sender, _to, _value);
        return true;
    }

    function balanceOf(address _owner) public view returns (uint256 balance) {
        return balances[_owner];
    }
}

contract StandardToken is ERC20, BasicToken {
    mapping (address => mapping (address => uint256)) internal allowed;

    function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
        require(_to != address(0));
        require(_value <= balances[_from]);
        require(_value <= allowed[_from][msg.sender]);

        balances[_from] = balances[_from].sub(_value);
        balances[_to] = balances[_to].add(_value);
        allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
        Transfer(_from, _to, _value);
        return true;
    }

    function approve(address _spender, uint256 _value) public returns (bool) {
        allowed[msg.sender][_spender] = _value;
        Approval(msg.sender, _spender, _value);
        return true;
    }

    function allowance(address _owner, address _spender) public view returns (uint256) {
        return allowed[_owner][_spender];
    }

    function increaseApproval(address _spender, uint _addedValue) public returns (bool) {
        allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_addedValue);
        Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
        return true;
    }

    function decreaseApproval(address _spender, uint _subtractedValue) public returns (bool) {
        uint oldValue = allowed[msg.sender][_spender];
        if (_subtractedValue > oldValue) {
            allowed[msg.sender][_spender] = 0;
        } else {
            allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
        }
        Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
        return true;
    }
}

contract PausableToken is StandardToken, Pausable {
    function transfer(address _to, uint256 _value) public whenNotPaused returns (bool) {
        return super.transfer(_to, _value);
    }

    function transferFrom(address _from, address _to, uint256 _value) public whenNotPaused returns (bool) {
        return super.transferFrom(_from, _to, _value);
    }

    function approve(address _spender, uint256 _value) public whenNotPaused returns (bool) {
        return super.approve(_spender, _value);
    }

    function increaseApproval(address _spender, uint _addedValue) public whenNotPaused returns (bool success) {
        return super.increaseApproval(_spender, _addedValue);
    }

    function decreaseApproval(address _spender, uint _subtractedValue) public whenNotPaused returns (bool success) {
        return super.decreaseApproval(_spender, _subtractedValue);
    }
}

contract BoraToken is PausableToken {
    string public name;
    string public symbol;
    uint8 public decimals;

    event Burn(address to, uint256 amount, uint256 totalSupply);
    event Lock(address token, address beneficiary, uint256 amount, uint256 releaseTime);

    function BoraToken(uint256 _supply) public {
        require(_supply != 0);
        balances[msg.sender] = _supply;
        totalSupply_ = _supply;
        name = 'BORA';
        symbol = 'BORA';
        decimals = 18;
        Transfer(address(0), msg.sender, _supply);
    }

    function lock(address _donor, address _beneficiary, uint256 amount, uint256 _duration, bool _revocable) onlyOwner public returns (LockedToken) {
        uint256 releaseTime = now.add(_duration.mul(1 days));
        LockedToken lockedToken = new LockedToken(this, _donor, _beneficiary, releaseTime, _revocable);
        BasicToken.transfer(lockedToken, amount);
        Lock(lockedToken, _beneficiary, lockedToken.balanceOf(), releaseTime);
        return lockedToken;
    }

    function burn(uint256 _amount) onlyOwner public {
        require(_amount <= balances[msg.sender]);
        balances[msg.sender] = balances[msg.sender].sub(_amount);
        totalSupply_ = totalSupply_.sub(_amount);
        Burn(msg.sender, _amount, totalSupply_);
        Transfer(msg.sender, address(0), _amount);
    }
}


contract LockedToken {
    ERC20Basic public token;
    address public donor;
    address public beneficiary;
    uint256 public releaseTime;
    bool public revocable;

    event Claim(address beneficiary, uint256 amount, uint256 releaseTime);
    event Revoke(address donor, uint256 amount);

    function LockedToken(ERC20Basic _token, address _donor, address _beneficiary, uint256 _releaseTime, bool _revocable) public {
        require(_token != address(0));
        require(_donor != address(0));
        require(_beneficiary != address(0));
        require(_releaseTime > now);

        token = ERC20Basic(_token);
        donor = _donor;
        beneficiary = _beneficiary;
        releaseTime = _releaseTime;
        revocable = _revocable;
    }

    function balanceOf() public view returns (uint256) {
        return token.balanceOf(this);
    }

    function revoke() public {
        require(revocable);
        require(msg.sender == donor);

        uint amount = token.balanceOf(this);
        require(amount > 0);
        token.transfer(donor, amount);
        Revoke(donor, amount);
    }

    function claim() public {
        require(now >= releaseTime);

        uint amount = token.balanceOf(this);
        require(amount > 0);
        token.transfer(beneficiary, amount);
        Claim(beneficiary, amount, releaseTime);
    }
}