// SPDX-License-Identifier: Unlicense
pragma solidity ^0.8.24;

import "./DAO.sol";

contract Proposals is DAOContract {
    struct Attestation {
        address sender;
        uint amount;
    }

    enum Stage {
        Proposal,
        Referendum0,
        Referendum1,
        Referendum100,
        Closed
    }
    struct Proposal {
        address sender;
        string contentId;
        uint startTime;
        Stage stage;
        mapping(uint => Attestation) attestations;
        uint attestationCount;
    }

    mapping(uint => Proposal) proposals;
    uint proposalCount;

    constructor(DAO dao) DAOContract(dao) {}

    function propose(
        string calldata contentId
    ) external returns (uint proposalIndex) {
        proposalIndex = proposalCount++;
        Proposal storage proposal = proposals[proposalIndex];
        proposal.startTime = block.timestamp;
        proposal.contentId = contentId;
    }

    function attest(uint proposalIndex, uint amount) external {
        // Since this is non-binding, non-encumbering, we only need to verify that
        // the sender actually has the rep they claim to stake.
        require(
            dao.balanceOf(msg.sender) >= amount,
            "Sender has insufficient REP balance"
        );
        Proposal storage proposal = proposals[proposalIndex];
        uint attestationIndex = proposal.attestationCount++;
        Attestation storage attestation = proposal.attestations[
            attestationIndex
        ];
        attestation.sender = msg.sender;
        attestation.amount = amount;
    }

    function evaluateAttestation(uint proposalIndex) external returns (bool) {
        Proposal storage proposal = proposals[proposalIndex];
        require(
            proposal.stage == Stage.Proposal,
            "Attestation only pertains to Proposal stage"
        );
        uint totalAttestation;
        for (uint i = 0; i < proposal.attestationCount; i++) {
            totalAttestation += proposal.attestations[i].amount;
        }
        bool meetsAttestation = 10 * totalAttestation >= dao.totalSupply();
        if (!meetsAttestation) {
            if (block.timestamp > proposal.startTime + 365 days) {
                proposal.stage = Stage.Closed;
                return false;
            }
            return false;
        }

        // Initiate validation pool
        proposal.stage = Stage.Referendum0;
        // TODO: make referendum0 duration a parameter
    }
}