🧑‍💻 간단한 DAO 스마트 컨트랙트 예시 (Solidity)

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

contract SimpleDAO {
    struct Proposal {
        uint id;
        address proposer;
        string description;
        uint forVotes;
        uint againstVotes;
        uint endTime;
        bool executed;
    }
    
    mapping(uint => Proposal) public proposals;
    mapping(address => uint) public tokenBalance;
    mapping(uint => mapping(address => bool)) public hasVoted;
    
    uint public proposalCount;
    uint public votingPeriod = 3 days;
    
    event ProposalCreated(uint id, address proposer, string description);
    event Voted(uint proposalId, address voter, bool support);
    event ProposalExecuted(uint id);
    
    // 토큰 분배 (실제로는 더 복잡한 로직이 필요)
    function distributeTokens(address to, uint amount) public {
        tokenBalance[to] += amount;
    }
    
    // 제안 생성
    function createProposal(string memory description) public returns (uint) {
        require(tokenBalance[msg.sender] > 0, "Must hold tokens to create proposal");
        
        proposalCount++;
        proposals[proposalCount] = Proposal({
            id: proposalCount,
            proposer: msg.sender,
            description: description,
            forVotes: 0,
            againstVotes: 0,
            endTime: block.timestamp + votingPeriod,
            executed: false
        });
        
        emit ProposalCreated(proposalCount, msg.sender, description);
        return proposalCount;
    }
    
    // 투표
    function vote(uint proposalId, bool support) public {
        Proposal storage proposal = proposals[proposalId];
        require(block.timestamp < proposal.endTime, "Voting period ended");
        require(!hasVoted[proposalId][msg.sender], "Already voted");
        require(tokenBalance[msg.sender] > 0, "Must hold tokens to vote");
        
        hasVoted[proposalId][msg.sender] = true;
        
        if (support) {
            proposal.forVotes += tokenBalance[msg.sender];
        } else {
            proposal.againstVotes += tokenBalance[msg.sender];
        }
        
        emit Voted(proposalId, msg.sender, support);
    }
    
    // 제안 실행
    function executeProposal(uint proposalId) public {
        Proposal storage proposal = proposals[proposalId];
        require(block.timestamp >= proposal.endTime, "Voting still in progress");
        require(!proposal.executed, "Proposal already executed");
        require(proposal.forVotes > proposal.againstVotes, "Proposal rejected");
        
        proposal.executed = true;
        
        // 실제 실행 로직 (여기서는 단순화)
        // 실제로는 다른 컨트랙트 호출이나 상태 변경 등이 포함됨
        
        emit ProposalExecuted(proposalId);
    }
}