pragma solidity ^0.4.16;

contract Token {
    bytes32 public standard;
    bytes32 public name;
    bytes32 public symbol;
    uint256 public totalSupply;
    uint8 public decimals;
    bool public allowTransactions;
    mapping (address => uint256) public balanceOf;
    mapping (address => mapping (address => uint256)) public allowance;
    function transfer(address _to, uint256 _value) returns (bool success);
    function approveAndCall(address _spender, uint256 _value, bytes _extraData) returns (bool success);
    function approve(address _spender, uint256 _value) returns (bool success);
    function transferFrom(address _from, address _to, uint256 _value) returns (bool success);
}

contract Exchange {
  function assert(bool assertion) {
    if (!assertion) throw;
  }
  function safeMul(uint a, uint b) returns (uint) {
    uint c = a * b;
    assert(a == 0 || c / a == b);
    return c;
  }

  function safeSub(uint a, uint b) returns (uint) {
    assert(b <= a);
    return a - b;
  }

  function safeAdd(uint a, uint b) returns (uint) {
    uint c = a + b;
    assert(c>=a && c>=b);
    return c;
  }
  address public owner;
  mapping (address => uint256) public invalidOrder;
  event SetOwner(address indexed previousOwner, address indexed newOwner);
  modifier onlyOwner {
    assert(msg.sender == owner);
    _;
  }
  function setOwner(address newOwner) onlyOwner {
    SetOwner(owner, newOwner);
    owner = newOwner;
  }
  function getOwner() returns (address out) {
    return owner;
  }
  function invalidateOrdersBefore(address user, uint256 nonce) onlyAdmin {
    if (nonce < invalidOrder[user]) throw;
    invalidOrder[user] = nonce;
  }

  mapping (address => mapping (address => uint256)) public tokens; //mapping of token addresses to mapping of account balances

  mapping (address => bool) public admins;
  mapping (address => uint256) public lastActiveTransaction;
  mapping (bytes32 => uint256) public orderFills;
  address public feeAccount;
  uint256 public inactivityReleasePeriod;
  mapping (bytes32 => bool) public traded;
  mapping (bytes32 => bool) public withdrawn;
  event Order(address tokenBuy, uint256 amountBuy, address tokenSell, uint256 amountSell, uint256 expires, uint256 nonce, address user, uint8 v, bytes32 r, bytes32 s);
  event Cancel(address tokenBuy, uint256 amountBuy, address tokenSell, uint256 amountSell, uint256 expires, uint256 nonce, address user, uint8 v, bytes32 r, bytes32 s);
  event Trade(address tokenBuy, uint256 amountBuy, address tokenSell, uint256 amountSell, address get, address give);
  event Deposit(address token, address user, uint256 amount, uint256 balance);
  event Withdraw(address token, address user, uint256 amount, uint256 balance);

  function setInactivityReleasePeriod(uint256 expiry) onlyAdmin returns (bool success) {
    if (expiry > 1000000) throw;
    inactivityReleasePeriod = expiry;
    return true;
  }

  function Exchange(address feeAccount_) {
    owner = msg.sender;
    feeAccount = feeAccount_;
    inactivityReleasePeriod = 100000;
  }

  function setAdmin(address admin, bool isAdmin) onlyOwner {
    admins[admin] = isAdmin;
  }

  modifier onlyAdmin {
    if (msg.sender != owner && !admins[msg.sender]) throw;
    _;
  }

  function() external {
    throw;
  }

  function depositToken(address token, uint256 amount) {
    tokens[token][msg.sender] = safeAdd(tokens[token][msg.sender], amount);
    lastActiveTransaction[msg.sender] = block.number;
    if (!Token(token).transferFrom(msg.sender, this, amount)) throw;
    Deposit(token, msg.sender, amount, tokens[token][msg.sender]);
  }

  function deposit() payable {
    tokens[address(0)][msg.sender] = safeAdd(tokens[address(0)][msg.sender], msg.value);
    lastActiveTransaction[msg.sender] = block.number;
    Deposit(address(0), msg.sender, msg.value, tokens[address(0)][msg.sender]);
  }

  function withdraw(address token, uint256 amount) returns (bool success) {
    if (safeSub(block.number, lastActiveTransaction[msg.sender]) < inactivityReleasePeriod) throw;
    if (tokens[token][msg.sender] < amount) throw;
    tokens[token][msg.sender] = safeSub(tokens[token][msg.sender], amount);
    if (token == address(0)) {
      if (!msg.sender.send(amount)) throw;
    } else {
      if (!Token(token).transfer(msg.sender, amount)) throw;
    }
    Withdraw(token, msg.sender, amount, tokens[token][msg.sender]);
  }

  function adminWithdraw(address token, uint256 amount, address user, uint256 nonce, uint8 v, bytes32 r, bytes32 s, uint256 feeWithdrawal) onlyAdmin returns (bool success) {
    bytes32 hash = keccak256(this, token, amount, user, nonce);
    if (withdrawn[hash]) throw;
    withdrawn[hash] = true;
    if (ecrecover(keccak256("\x19Ethereum Signed Message:\n32", hash), v, r, s) != user) throw;
    if (feeWithdrawal > 50 finney) feeWithdrawal = 50 finney;
    if (tokens[token][user] < amount) throw;
    tokens[token][user] = safeSub(tokens[token][user], amount);
    tokens[token][feeAccount] = safeAdd(tokens[token][feeAccount], safeMul(feeWithdrawal, amount) / 1 ether);
    amount = safeMul((1 ether - feeWithdrawal), amount) / 1 ether;
    if (token == address(0)) {
      if (!user.send(amount)) throw;
    } else {
      if (!Token(token).transfer(user, amount)) throw;
    }
    lastActiveTransaction[user] = block.number;
    Withdraw(token, user, amount, tokens[token][user]);
  }

  function balanceOf(address token, address user) constant returns (uint256) {
    return tokens[token][user];
  }

  function trade(uint256[8] tradeValues, address[4] tradeAddresses, uint8[2] v, bytes32[4] rs) onlyAdmin returns (bool success) {
    /* amount is in amountBuy terms */
    /* tradeValues
       [0] amountBuy
       [1] amountSell
       [2] expires
       [3] nonce
       [4] amount
       [5] tradeNonce
       [6] feeMake
       [7] feeTake
     tradeAddressses
       [0] tokenBuy
       [1] tokenSell
       [2] maker
       [3] taker
     */
    if (invalidOrder[tradeAddresses[2]] > tradeValues[3]) throw;
    bytes32 orderHash = keccak256(this, tradeAddresses[0], tradeValues[0], tradeAddresses[1], tradeValues[1], tradeValues[2], tradeValues[3], tradeAddresses[2]);
    if (ecrecover(keccak256("\x19Ethereum Signed Message:\n32", orderHash), v[0], rs[0], rs[1]) != tradeAddresses[2]) throw;
    bytes32 tradeHash = keccak256(orderHash, tradeValues[4], tradeAddresses[3], tradeValues[5]); 
    if (ecrecover(keccak256("\x19Ethereum Signed Message:\n32", tradeHash), v[1], rs[2], rs[3]) != tradeAddresses[3]) throw;
    if (traded[tradeHash]) throw;
    traded[tradeHash] = true;
    if (tradeValues[6] > 100 finney) tradeValues[6] = 100 finney;
    if (tradeValues[7] > 100 finney) tradeValues[7] = 100 finney;
    if (safeAdd(orderFills[orderHash], tradeValues[4]) > tradeValues[0]) throw;
    if (tokens[tradeAddresses[0]][tradeAddresses[3]] < tradeValues[4]) throw;
    if (tokens[tradeAddresses[1]][tradeAddresses[2]] < (safeMul(tradeValues[1], tradeValues[4]) / tradeValues[0])) throw;
    tokens[tradeAddresses[0]][tradeAddresses[3]] = safeSub(tokens[tradeAddresses[0]][tradeAddresses[3]], tradeValues[4]);
    tokens[tradeAddresses[0]][tradeAddresses[2]] = safeAdd(tokens[tradeAddresses[0]][tradeAddresses[2]], safeMul(tradeValues[4], ((1 ether) - tradeValues[6])) / (1 ether));
    tokens[tradeAddresses[0]][feeAccount] = safeAdd(tokens[tradeAddresses[0]][feeAccount], safeMul(tradeValues[4], tradeValues[6]) / (1 ether));
    tokens[tradeAddresses[1]][tradeAddresses[2]] = safeSub(tokens[tradeAddresses[1]][tradeAddresses[2]], safeMul(tradeValues[1], tradeValues[4]) / tradeValues[0]);
    tokens[tradeAddresses[1]][tradeAddresses[3]] = safeAdd(tokens[tradeAddresses[1]][tradeAddresses[3]], safeMul(safeMul(((1 ether) - tradeValues[7]), tradeValues[1]), tradeValues[4]) / tradeValues[0] / (1 ether));
    tokens[tradeAddresses[1]][feeAccount] = safeAdd(tokens[tradeAddresses[1]][feeAccount], safeMul(safeMul(tradeValues[7], tradeValues[1]), tradeValues[4]) / tradeValues[0] / (1 ether));
    orderFills[orderHash] = safeAdd(orderFills[orderHash], tradeValues[4]);
    lastActiveTransaction[tradeAddresses[2]] = block.number;
    lastActiveTransaction[tradeAddresses[3]] = block.number;
  }
}

pragma solidity ^0.4.11;


/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
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;
  }
}



/**
 * @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;


  /**
   * @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 {
    require(newOwner != address(0));      
    owner = newOwner;
  }

}


contract Crowdsale {
  using SafeMath for uint256;

  // The token being sold
  MintableToken public token;

  // start and end timestamps where investments are allowed (both inclusive)
  uint256 public startTime;
  uint256 public endTime;

  // address where funds are collected
  address public wallet;

  // how many token units a buyer gets per wei
  uint256 public rate;

  // amount of raised money in wei
  uint256 public weiRaised;

  /**
   * event for token purchase logging
   * @param purchaser who paid for the tokens
   * @param beneficiary who got the tokens
   * @param value weis paid for purchase
   * @param amount amount of tokens purchased
   */ 
  event TokenPurchase(address indexed purchaser, address indexed beneficiary, uint256 value, uint256 amount);


  function Crowdsale(uint256 _startTime, uint256 _endTime, uint256 _rate, address _wallet) {
    require(_startTime >= now);
    require(_endTime >= _startTime);
    require(_rate > 0);
    require(_wallet != 0x0);

    token = createTokenContract();
    startTime = _startTime;
    endTime = _endTime;
    rate = _rate;
    wallet = _wallet;
  }

  // creates the token to be sold. 
  // override this method to have crowdsale of a specific mintable token.
  function createTokenContract() internal returns (MintableToken) {
    return new MintableToken();
  }


  // fallback function can be used to buy tokens
  function () payable {
    buyTokens(msg.sender);
  }

  // low level token purchase function
  function buyTokens(address beneficiary) payable {
    require(beneficiary != 0x0);
    require(validPurchase());

    uint256 weiAmount = msg.value;

    // calculate token amount to be created
    uint256 tokens = weiAmount.mul(rate);

    // update state
    weiRaised = weiRaised.add(weiAmount);

    token.mint(beneficiary, tokens);
    TokenPurchase(msg.sender, beneficiary, weiAmount, tokens);

    forwardFunds();
  }

  // send ether to the fund collection wallet
  // override to create custom fund forwarding mechanisms
  function forwardFunds() internal {
    wallet.transfer(msg.value);
  }

  // @return true if the transaction can buy tokens
  function validPurchase() internal constant returns (bool) {
    bool withinPeriod = now >= startTime && now <= endTime;
    bool nonZeroPurchase = msg.value != 0;
    return withinPeriod && nonZeroPurchase;
  }

  // @return true if crowdsale event has ended
  function hasEnded() public constant returns (bool) {
    return now > endTime;
  }


}


contract CappedCrowdsale is Crowdsale {
  using SafeMath for uint256;

  uint256 public cap;

  function CappedCrowdsale(uint256 _cap) {
    require(_cap > 0);
    cap = _cap;
  }

  // overriding Crowdsale#validPurchase to add extra cap logic
  // @return true if investors can buy at the moment
  function validPurchase() internal constant returns (bool) {
    bool withinCap = weiRaised.add(msg.value) <= cap;
    return super.validPurchase() && withinCap;
  }

  // overriding Crowdsale#hasEnded to add cap logic
  // @return true if crowdsale event has ended
  function hasEnded() public constant returns (bool) {
    bool capReached = weiRaised >= cap;
    return super.hasEnded() || capReached;
  }

}

contract WithdrawVault is Ownable {
    using SafeMath for uint256;

    mapping (address => uint256) public deposited;
    address public wallet;


    function WithdrawVault(address _wallet) {
        require(_wallet != 0x0);
        wallet = _wallet;
    }

    function deposit(address investor) onlyOwner payable {
        deposited[investor] = deposited[investor].add(msg.value);
    }

    function close() onlyOwner {
        wallet.transfer(this.balance);
    }

}




contract ERC20Basic {
  uint256 public totalSupply;
  function balanceOf(address who) constant returns (uint256);
  function transfer(address to, uint256 value) returns (bool);
  event Transfer(address indexed from, address indexed to, uint256 value);
}

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);
  event Approval(address indexed owner, address indexed spender, 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) {
    require(_to != address(0));

    // SafeMath.sub will throw if there is not enough balance.
    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 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 amount of tokens to be transferred
   */
  function transferFrom(address _from, address _to, uint256 _value) returns (bool) {
    require(_to != address(0));

    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);

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

  /**
   * @dev Approve 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 specifying the amount of tokens still available for the spender.
   */
  function allowance(address _owner, address _spender) constant returns (uint256 remaining) {
    return allowed[_owner][_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
   */
  function increaseApproval (address _spender, uint _addedValue) 
    returns (bool success) {
    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) 
    returns (bool success) {
    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 BurnableToken is StandardToken {

    /**
     * @dev Burns a specific amount of tokens.
     * @param _value The amount of token to be burned.
     */
    function burn(uint _value)
        public
    {
        require(_value > 0);

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

    event Burn(address indexed burner, uint indexed value);
}

contract MintableToken is StandardToken, Ownable {
  event Mint(address indexed to, uint256 amount);
  event MintFinished();

  bool public mintingFinished = false;


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

  /**
   * @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) onlyOwner canMint returns (bool) {
    totalSupply = totalSupply.add(_amount);
    balances[_to] = balances[_to].add(_amount);
    Mint(_to, _amount);
    Transfer(0x0, _to, _amount);
    return true;
  }

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









contract FinalizableCrowdsale is Crowdsale, Ownable {
  using SafeMath for uint256;

  bool public isFinalized = false;

  event Finalized();

  /**
   * @dev Must be called after crowdsale ends, to do some extra finalization
   * work. Calls the contract's finalization function.
   */
  function finalize() onlyOwner {
    require(!isFinalized);
    require(hasEnded());

    finalization();
    Finalized();
    
    isFinalized = true;
  }

  /**
   * @dev Can be overriden to add finalization logic. The overriding function
   * should call super.finalization() to ensure the chain of finalization is
   * executed entirely.
   */
  function finalization() internal {
  }
}

contract RefundVault is Ownable {
  using SafeMath for uint256;

  enum State { Active, Refunding, Closed }

  mapping (address => uint256) public deposited;
  address public wallet;
  State public state;

  event Closed();
  event RefundsEnabled();
  event Refunded(address indexed beneficiary, uint256 weiAmount);

  function RefundVault(address _wallet) {
    require(_wallet != 0x0);
    wallet = _wallet;
    state = State.Active;
  }

  function deposit(address investor) onlyOwner payable {
    deposited[investor] = deposited[investor].add(msg.value);
  }

  function close() onlyOwner {
    require(state == State.Active);
    state = State.Closed;
    Closed();
    wallet.transfer(this.balance);
  }

  function enableRefunds() onlyOwner {
    require(state == State.Active);
    state = State.Refunding;
    RefundsEnabled();
  }

  function refund(address investor) {
    require(state == State.Refunding);
    uint256 depositedValue = deposited[investor];
    deposited[investor] = 0;
    investor.transfer(depositedValue);
    Refunded(investor, depositedValue);
  }
}









contract Pausable is Ownable {
  event Pause();
  event Unpause();

  bool public paused = false;


  /**
   * @dev Modifier to make a function callable only when the contract is not paused.
   */
  modifier whenNotPaused() {
    require(!paused);
    _;
  }

  /**
   * @dev Modifier to make a function callable only when the contract is paused.
   */
  modifier whenPaused() {
    require(paused);
    _;
  }

  /**
   * @dev called by the owner to pause, triggers stopped state
   */
  function pause() onlyOwner whenNotPaused public {
    paused = true;
    Pause();
  }

  /**
   * @dev called by the owner to unpause, returns to normal state
   */
  function unpause() onlyOwner whenPaused public {
    paused = false;
    Unpause();
  }
}

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 TokenRecipient {

    function tokenFallback(address sender, uint256 _value, bytes _extraData) returns (bool) {}

}





contract NPXSToken is MintableToken, BurnableToken, PausableToken {

    string public constant name = "Pundi X Token";
    string public constant symbol = "NPXS";
    uint8 public constant decimals = 18;


    function NPXSToken() {

    }


    // --------------------------------------------------------

    function transferFrom(address _from, address _to, uint256 _value) public whenNotPaused returns (bool) {
        bool result = super.transferFrom(_from, _to, _value);
        return result;
    }

    mapping (address => bool) stopReceive;

    function setStopReceive(bool stop) {
        stopReceive[msg.sender] = stop;
    }

    function getStopReceive() constant public returns (bool) {
        return stopReceive[msg.sender];
    }

    function transfer(address _to, uint256 _value) public whenNotPaused returns (bool) {
        require(!stopReceive[_to]);
        bool result = super.transfer(_to, _value);
        return result;
    }


    function mint(address _to, uint256 _amount) onlyOwner canMint public returns (bool) {
        bool result = super.mint(_to, _amount);
        return result;
    }

    function burn(uint256 _value) public {
        super.burn(_value);
    }

    // --------------------------------------------------------

    // 锁仓
    function pause() onlyOwner whenNotPaused public {
        super.pause();
    }

    // 解仓
    function unpause() onlyOwner whenPaused public {
        super.unpause();
    }

    function transferAndCall(address _recipient, uint256 _amount, bytes _data) {
        require(_recipient != address(0));
        require(_amount <= balances[msg.sender]);

        balances[msg.sender] = balances[msg.sender].sub(_amount);
        balances[_recipient] = balances[_recipient].add(_amount);

        require(TokenRecipient(_recipient).tokenFallback(msg.sender, _amount, _data));
        Transfer(msg.sender, _recipient, _amount);
    }

}