pragma solidity ^0.4.15;

import './SafeMath.sol';
import './GitToken.sol';
import './Signed.sol';

contract GitTokenAuction is Signed {

  using SafeMath for uint;
  using SafeMath for uint[];

  struct AuctionDetails {
    uint startDate;
    uint endDate;
    uint lockDate;
    uint tokensOffered;
    uint initialPrice;
    uint fundsCollected;
    uint numBids;
    uint wtdAvgPrice;
    uint[] values;
    uint[] prices;
  }

  mapping(address => mapping(uint => AuctionDetails)) auctions;
  mapping(address => uint) rounds;
  uint public fee;

  event Auction(
    address indexed gittoken,
    uint round,
    uint startDate,
    uint endDate,
    uint tokensOffered,
    uint initialPrice
  );

  event Bid(
    address indexed gittoken,
    address bidder,
    uint round,
    uint price,
    uint tokens,
    uint value
  );

  function GitTokenAuction(uint _fee) Signed(msg.sender) public {
    fee = _fee > 0 ? _fee : 10**15; // 0.0001 ETH
  }

  function init(address _gittoken, uint _minPrice) onlyGitTokenSigner(_gittoken) public returns(bool success) {
      require(auctions[_gittoken][rounds[_gittoken]].endDate < now); //
      require(GitToken(_gittoken).balanceOf(address(this)) > 0); // ensure contract has tokens to auction

      rounds[_gittoken] += 1;

      auctions[_gittoken][rounds[_gittoken]].startDate = now; // + 86400*3; // t+3 days
      auctions[_gittoken][rounds[_gittoken]].endDate = now + 86400*12; // t+12 days
      auctions[_gittoken][rounds[_gittoken]].tokensOffered = GitToken(_gittoken).balanceOf(address(this)); // currently held token balance
      auctions[_gittoken][rounds[_gittoken]].initialPrice = _minPrice;

      Auction(
        _gittoken,
        rounds[_gittoken],
        auctions[_gittoken][rounds[_gittoken]].startDate,
        auctions[_gittoken][rounds[_gittoken]].endDate,
        auctions[_gittoken][rounds[_gittoken]].tokensOffered,
        auctions[_gittoken][rounds[_gittoken]].initialPrice
      );

      return true;
  }

  function bid( address _gittoken, uint _price) payable validate(_gittoken, _price)
    public returns(bool success)
  {
    auctions[_gittoken][rounds[_gittoken]].values.push(msg.value);
    auctions[_gittoken][rounds[_gittoken]].prices.push(_price);

    auctions[_gittoken][rounds[_gittoken]].wtdAvgPrice =
      auctions[_gittoken][rounds[_gittoken]].values.wtdAvg(
        auctions[_gittoken][rounds[_gittoken]].prices
      );

    uint tokens = (msg.value / auctions[_gittoken][rounds[_gittoken]].wtdAvgPrice) * 10 ** GitToken(_gittoken).decimals();
    uint funds = msg.value - fee;

    require(GitToken(_gittoken).transfer(msg.sender, tokens));
    require(_gittoken.send(funds));

    Bid(
      _gittoken,
      msg.sender,
      rounds[_gittoken],
      auctions[_gittoken][rounds[_gittoken]].wtdAvgPrice,
      tokens,
      funds
    );

    return true;
  }

  function withdraw(address _gittoken) onlyGitTokenSigner(_gittoken) public returns (bool success) {
    require(auctions[_gittoken][rounds[_gittoken]].endDate < now);
    uint tokens = GitToken(_gittoken).balanceOf(address(this));
    require(GitToken(_gittoken).transfer(_gittoken, tokens));
    return true;
  }

  modifier validate(address _gittoken, uint _price) {
      require(auctions[_gittoken][rounds[_gittoken]].startDate <= now); // ensure the start date as started
      require(auctions[_gittoken][rounds[_gittoken]].endDate >= now); // ensure that the end date has not expired
      require(msg.value >= _price && _price > 0);
      _;
  }

  modifier onlyGitTokenSigner(address _gittoken) {
      require(GitToken(_gittoken).isSigner(msg.sender));
      _;
  }

}