dvd5.sol

contract TheRewarderPool {

    // Minimum duration of each round of rewards in seconds
    uint256 private constant REWARDS_ROUND_MIN_DURATION = 5 days;
...
    function deposit(uint256 amountToDeposit) external {
        require(amountToDeposit > 0, "Must deposit tokens");
        
        accToken.mint(msg.sender, amountToDeposit);
        distributeRewards();

        require(
            liquidityToken.transferFrom(msg.sender, address(this), amountToDeposit)
        );
    }

    function withdraw(uint256 amountToWithdraw) external {
        accToken.burn(msg.sender, amountToWithdraw);
        require(liquidityToken.transfer(msg.sender, amountToWithdraw));
    }

    function distributeRewards() public returns (uint256) {
        uint256 rewards = 0;

        if(isNewRewardsRound()) {
            _recordSnapshot();
        }        
        
        uint256 totalDeposits = accToken.totalSupplyAt(lastSnapshotIdForRewards);
        uint256 amountDeposited = accToken.balanceOfAt(msg.sender, lastSnapshotIdForRewards);

        if (amountDeposited > 0 && totalDeposits > 0) {
            rewards = (amountDeposited * 100 * 10 ** 18) / totalDeposits;

            if(rewards > 0 && !_hasRetrievedReward(msg.sender)) {
                rewardToken.mint(msg.sender, rewards);
                lastRewardTimestamps[msg.sender] = block.timestamp;
            }
        }

        return rewards;     
    }

    function _recordSnapshot() private {
        lastSnapshotIdForRewards = accToken.snapshot();
        lastRecordedSnapshotTimestamp = block.timestamp;
        roundNumber++;
    }

    function _hasRetrievedReward(address account) private view returns (bool) {
        return (
            lastRewardTimestamps[account] >= lastRecordedSnapshotTimestamp &&
            lastRewardTimestamps[account] <= lastRecordedSnapshotTimestamp + REWARDS_ROUND_MIN_DURATION
        );
    }

    function isNewRewardsRound() public view returns (bool) {
        return block.timestamp >= lastRecordedSnapshotTimestamp + REWARDS_ROUND_MIN_DURATION;
    }
}