// ------------------------------------------------------------------------------
// This file is part of netvote.
//
// netvote is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// netvote is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with solidity.  If not, see <http://www.gnu.org/licenses/>
//
// (c) 2017 netvote contributors.
//------------------------------------------------------------------------------

pragma solidity ^0.4.17;

import "../basic/BasicElection.sol";


/**
 * @title TokenElection
 * @dev Allows token holders to vote
 */
contract TokenElection is BasicElection {

    address public tokenAddress;
    uint public balanceTime;

    /**
      * @dev Constructor for creating a BasicElection
      * @param hashedUserId bytes32 sha3 hash of external userId
      * @param allowanceAddress The address of global allowance contract.
      * @param ownerOfAllowance The owner of the Vote Allowance to deduct from.
      * @param allowUpdates Whether to allow Voters to update their vote.
      * @param revealerAddress The address of the Key Revealer that will post the Key.
      * @param location The location reference for the ballot metadata (e.g., IPFS Reference)
      * @param gatewayAddress The address of the Vote Gateway that will submit votes.
      * @param autoActivate Automatically activate this election to allow votes
      * @param erc20Token Address of token whose holders are voting
      * @param balanceTimestamp Timestamp for balance evaluation for weighted voting
      */
    function TokenElection(
        bytes32 hashedUserId,
        address allowanceAddress,
        address ownerOfAllowance,
        bool allowUpdates,
        address revealerAddress,
        string location,
        address gatewayAddress,
        bool autoActivate,
        address erc20Token,
        uint balanceTimestamp) BasicElection(hashedUserId, allowanceAddress, ownerOfAllowance, allowUpdates, revealerAddress, location, gatewayAddress, false) public
    {
        require(erc20Token != address(0));
        require(isContract(erc20Token));
        electionType = "TOKEN";
        tokenAddress = erc20Token;

        //balance must be in past for gateway-confirmed token elections
        require(balanceTimestamp < now);
        balanceTime = balanceTimestamp;

        if (autoActivate) {
            activate();
        }
    }

    function isContract(address addr) internal constant returns (bool) {
        uint size;
        assembly { size := extcodesize(addr) }
        return size > 0;
    }

}