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

import {ERC721} from "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "./ReputationHolder.sol";

/// This contract must manage validation pools and reputation,
/// because otherwise there's no way to enforce appropriate permissions on
/// transfer of value between reputation NFTs.
contract DAO is ERC721("Reputation", "REP"), ReputationHolder {
    mapping(uint256 tokenId => uint256) _tokenValues;
    uint256 _nextTokenId;

    /// Inspect the value of a given reputation NFT
    function valueOf(uint256 tokenId) public view returns (uint256 value) {
        value = _tokenValues[tokenId];
    }

    /// Internal function to mint a new reputation NFT
    function mint() internal returns (uint256 tokenId) {
        // Generate a new (sequential) ID for the token
        tokenId = _nextTokenId++;
        // Mint the token, initially to be owned by the current contract.
        _mint(address(this), tokenId);
    }

    /// Internal function to transfer value from one reputation token to another
    function transferValueFrom(
        uint256 fromTokenId,
        uint256 toTokenId,
        uint256 amount
    ) internal {
        require(amount >= 0);
        require(valueOf(fromTokenId) >= amount);
        _tokenValues[fromTokenId] -= amount;
        _tokenValues[toTokenId] += amount;
    }
}