Voting module

contracts/modules/Checkpoint/WeightedVoteCheckpoint.sol

@@ -0,0 +1,141 @@
+pragma solidity ^0.4.24;
+
+import "./ICheckpoint.sol";
+import "../Module.sol";
+import "openzeppelin-solidity/contracts/math/SafeMath.sol";
+
+/**
+ * @title Checkpoint module for token weighted vote
+ * @notice This voting system uses public votes
+ */
+contract WeightedVoteCheckpoint is ICheckpoint, Module {
+    using SafeMath for uint256;
+
+    struct Ballot {
+        uint256 checkpointId;
+        uint256 totalSupply;
+        uint256 startTime;
+        uint256 endTime;
+        uint256 cumulativeYes;
+        uint256 cumulativeNo;
+        uint256 numVotes;
+        mapping(address => Vote) voteByAddress;
+        bool isActive;
+    }
+
+    Ballot[] public ballots;
+
+    struct Vote {
+        uint256 time;
+        uint256 weight;
+        bool vote;
+    }
+
+    event BallotCreated(uint256 _startTime, uint256 _endTime, uint256 _ballotId, uint256 _checkpointId);
+    event VoteCasted(uint256 _ballotId, uint256 _time, address indexed _investor, uint256 _weight, bool _vote);
+    event BallotActiveStatsChanged(uint256 _ballotId, bool _isActive);
+
+    /**
+     * @notice Constructor
+     * @param _securityToken Address of the security token
+     * @param _polyAddress Address of the polytoken
+     */
+    constructor(address _securityToken, address _polyAddress) public Module(_securityToken, _polyAddress) {
+
+    }
+
+    /**
+     * @notice Queries the result of a given ballot
+     * @param _ballotId Id of the target ballot
+     * @return uint256 cummulativeYes
+     * @return uint256 cummulativeNo
+     * @return uint256 totalAbstain
+     * @return uint256 remainingTime
+     */
+    function getResults(uint256 _ballotId) public view returns (uint256 cummulativeYes, uint256 cummulativeNo, uint256 totalAbstain, uint256 remainingTime) {
+        uint256 abstain = (ballots[_ballotId].totalSupply.sub(ballots[_ballotId].cumulativeYes)).sub(ballots[_ballotId].cumulativeNo);
+        uint256 time = (ballots[_ballotId].endTime > now) ? ballots[_ballotId].endTime.sub(now) : 0;
+        return (ballots[_ballotId].cumulativeYes, ballots[_ballotId].cumulativeNo, abstain, time);
+    }
+
+    /**
+     * @notice Allows a token holder to cast their vote on a specific ballot
+     * @param _vote The vote (true/false) in favor or against the proposal
+     * @param _ballotId The index of the target ballot
+     * @return bool success
+     */
+    function castVote(bool _vote, uint256 _ballotId) public returns (bool) {
+        require(now > ballots[_ballotId].startTime && now < ballots[_ballotId].endTime, "Voting period is not active.");
+        require(ballots[_ballotId].voteByAddress[msg.sender].time == 0, "Token holder has already voted.");
+        require(ballots[_ballotId].isActive == true, "This ballot is deactiveated.");
+        uint256 checkpointId = ballots[_ballotId].checkpointId;
+        uint256 weight = ISecurityToken(securityToken).balanceOfAt(msg.sender,checkpointId);
+        require(weight > 0, "Token Holder balance is zero.");
+        ballots[_ballotId].voteByAddress[msg.sender].time = now;
+        ballots[_ballotId].voteByAddress[msg.sender].weight = weight;
+        ballots[_ballotId].voteByAddress[msg.sender].vote = _vote;
+        ballots[_ballotId].numVotes = ballots[_ballotId].numVotes.add(1);
+        if (_vote == true) {
+            ballots[_ballotId].cumulativeYes = ballots[_ballotId].cumulativeYes.add(weight);
+        } else {
+            ballots[_ballotId].cumulativeNo = ballots[_ballotId].cumulativeNo.add(weight);
+        }
+        emit VoteCasted(_ballotId, now, msg.sender, weight, _vote);
+        return true;
+    }
+
+    /**
+     * @notice Allows the token issuer to create a ballot
+     * @param _duration The duration of the voting period in seconds
+     * @return bool success
+     */
+    function createBallot(uint256 _duration) public onlyOwner {
+        require(_duration > 0, "Incorrect ballot duration.");
+        uint256 checkpointId = ISecurityToken(securityToken).createCheckpoint();
+        uint256 endTime = now.add(_duration);
+        createCustomBallot(now, endTime, checkpointId);
+    }
+
+    /**
+     * @notice Allows the token issuer to create a ballot with custom settings
+     * @param _startTime Start time of the voting period in Unix Epoch time
+     * @param _endTime End time of the voting period in Unix Epoch time
+     * @param _checkpointId Index of the checkpoint to use for token balances
+     * @return bool success
+     */
+    function createCustomBallot(uint256 _startTime, uint256 _endTime, uint256 _checkpointId) public onlyOwner {
+        require(_endTime > _startTime, "Ballot end time must be later than start time.");
+        uint256 ballotId = ballots.length;
+        uint256 supplyAtCheckpoint = ISecurityToken(securityToken).totalSupplyAt(_checkpointId);
+        ballots.push(Ballot(_checkpointId,supplyAtCheckpoint,_startTime,_endTime,0,0,0, true));
+        emit BallotCreated(_startTime, _endTime, ballotId, _checkpointId);
+    }
+
+    /**
+     * @notice Allows the token issuer to set the active stats of a ballot
+     * @param _ballotId The index of the target ballot
+     * @param _isActive The bool value of the active stats of the ballot
+     * @return bool success
+     */
+    function setActiveStatsBallot(uint256 _ballotId, bool _isActive) public onlyOwner {
+        require(now < ballots[_ballotId].endTime, "This ballot has already ended.");
+        require(ballots[_ballotId].isActive != _isActive, "Active state unchanged");
+        ballots[_ballotId].isActive = _isActive;
+        emit BallotActiveStatsChanged(_ballotId, _isActive);
+    }
+
+
+    function getInitFunction() public returns(bytes4) {
+        return bytes4(0);
+    }
+
+    /**
+     * @notice Return the permissions flag that are associated with STO
+     * @return bytes32 array
+     */
+    function getPermissions() public view returns(bytes32[]) {
+        bytes32[] memory allPermissions = new bytes32[](0);
+        return allPermissions;
+    }
+
+}

contracts/modules/Checkpoint/WeightedVoteCheckpointFactory.sol

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+pragma solidity ^0.4.24;
+
+import "./WeightedVoteCheckpoint.sol";
+import "../ModuleFactory.sol";
+
+/**
+ * @title Factory for deploying WeightedVoteCheckpoint module
+ */
+contract WeightedVoteCheckpointFactory is ModuleFactory {
+
+    /**
+     * @notice Constructor
+     * @param _polyAddress Address of the polytoken
+     * @param _setupCost Setup cost of the module
+     * @param _usageCost Usage cost of the module
+     * @param _subscriptionCost Subscription cost of the module
+     */
+    constructor (address _polyAddress, uint256 _setupCost, uint256 _usageCost, uint256 _subscriptionCost) public
+    ModuleFactory(_polyAddress, _setupCost, _usageCost, _subscriptionCost)
+    {
+        version = "1.0.0";
+        name = "WeightedVoteCheckpoint";
+        title = "Weighted Vote Checkpoint";
+        description = "Weighted votes based on token amount";
+        compatibleSTVersionRange["lowerBound"] = VersionUtils.pack(uint8(0), uint8(0), uint8(0));
+        compatibleSTVersionRange["upperBound"] = VersionUtils.pack(uint8(0), uint8(0), uint8(0));
+
+    }
+
+    /**
+     * @notice used to launch the Module with the help of factory
+     * @return address Contract address of the Module
+     */
+    function deploy(bytes /* _data */) external returns(address) {
+        if (setupCost > 0)
+            require(polyToken.transferFrom(msg.sender, owner, setupCost), "Failed transferFrom because of sufficent Allowance is not provided");
+        return address(new WeightedVoteCheckpoint(msg.sender, address(polyToken)));
+    }
+
+     /**
+     * @notice Type of the Module factory
+     */
+    function getTypes() external view returns(uint8[]) {
+        uint8[] memory res = new uint8[](1);
+        res[0] = 4;
+        return res;
+    }
+
+    /**
+     * @notice Get the name of the Module
+     */
+    function getName() public view returns(bytes32) {
+        return name;
+    }
+
+    /**
+     * @notice Get the description of the Module
+     */
+    function getDescription() external view returns(string) {
+        return description;
+    }
+
+    /**
+     * @notice Get the title of the Module
+     */
+    function getTitle() external view returns(string) {
+        return title;
+    }
+
+    /**
+     * @notice Get the version of the Module
+     */
+    function getVersion() external view returns(string) {
+        return version;
+    }
+
+    /**
+     * @notice Get the setup cost of the module
+     */
+    function getSetupCost() external view returns (uint256) {
+        return setupCost;
+    }
+
+    /**
+     * @notice Get the Instructions that helped to used the module
+     */
+    function getInstructions() external view returns(string) {
+        return "Create a vote which allows token holders to vote on an issue with a weight proportional to their balances at the point the vote is created.";
+    }
+
+    /**
+     * @notice Get the tags related to the module factory
+     */
+    function getTags() external view returns(bytes32[]) {
+        bytes32[] memory availableTags = new bytes32[](0);
+        return availableTags;
+    }
+}