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contracts...DAO.sol

//SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @custom:security contact [email protected]
contract DAO{

    //variables
    address public owner;
    mapping(address => bool) public members;
    uint public totalShares;
    mapping(address => uint) public shares;
    uint VotingPeriod = 7 days;


    //events
    event MemberAdded(address member);
    event MemberRemoved(address member);
    event SharesBought(address buyer,uint amount);
    event SharesSold(address seller,uint amount);
    event ProposalSubmitted(address proposer,string proposal);
    event Voted(address voter,uint proposalId,bool inFavor);
    event ProposalExecuted(address executor,uint proposalId);

    //Structs

    struct Proposal{
        address proposer;
        string description;
        uint votesFor;
        uint votesAgainst;
        bool executed;
        bool isApproved;
        mapping(address => bool)  hasVoted;
    }

    //Arrays
    //Proposal[] public proposals;

    //mapping
    mapping(uint => Proposal) proposals;
    uint proposalId;

    //Modifier

    modifier onlyOwner(){
        require(msg.sender == owner,"Only owner can call this");
        _;
    }

    //check member is member
    modifier onlyMember(){
        require(members[msg.sender],"Only member can call this");
        _;
    }

    //Constructor
    constructor()
    {
        owner = msg.sender;
        members[msg.sender] = true;
        totalShares = 100;
        shares[msg.sender]= 100;
    }

    //Functions
    function addMember(address _member) public onlyOwner{
        require(!members[_member],"Member does not exist");
        members[_member] = true;
        totalShares++;
        shares[_member] = 1;

        emit MemberAdded(_member);
    }

    function removeMember(address _member) public onlyOwner{
        require(members[_member],"Member does not exist");
        require(_member != owner,"Cannot remove owner!");
        members[_member] = false;
        totalShares --;
        shares[_member] = 0;
        
        emit MemberRemoved(_member);
    }

    function buyShares(uint _amount) public payable onlyMember{
        require(_amount <= (totalShares-shares[msg.sender]),"Not enough share available");
        uint cost = _amount * 1 ether;
        require(msg.value == cost,"Incorrect value sent");
        shares[msg.sender] +=_amount;
        totalShares += _amount;

        emit SharesBought(msg.sender,_amount);
    }

    function sellShares(uint _amount) public onlyOwner{
        require(shares[msg.sender]>=_amount,"Not enough shares");
        shares[msg.sender] -= _amount;
        totalShares -= _amount;

        payable(msg.sender).transfer(_amount * 1 ether);
        emit SharesSold(msg.sender,_amount);
    }
    function submitProposal(string memory _description) public onlyMember{
        proposalId++;
        Proposal storage proposal =  proposals[proposalId];
        proposal.proposer =  msg.sender;
        proposal.description = _description;
        proposal.votesFor = 0;
        proposal.votesAgainst = 0;
        proposal.executed = false;
        proposal.isApproved = false;
        proposal.hasVoted[msg.sender] = false;

        emit ProposalSubmitted(msg.sender,_description);
    }

    //Nice Functionality
    function vote(uint _proposalId,bool _inFavor) public onlyMember{
        Proposal storage proposal = proposals[_proposalId];
        require(!proposal.executed,"Proposal already executed");
        require(!proposal.hasVoted[msg.sender],"Already voted on proposal");
        if(_inFavor){
            proposal.votesFor += shares[msg.sender];
        }else{
            proposal.votesAgainst += shares[msg.sender];
        }
        proposal.hasVoted[msg.sender]= true;

        emit Voted(msg.sender,_proposalId,_inFavor);
    }

    function executeProposal(uint _proposalId) public onlyMember{
        Proposal storage proposal = proposals[_proposalId];
        require(!proposal.executed,"Proposal already executed");
        require(block.timestamp > VotingPeriod,"Voting period has not expired");
        /* uint votesNeeded = totalShares / 2;  */

        if(proposal.votesFor > proposal.votesAgainst){
            //Execute the proposal
            proposal.executed =  true;
            proposal.isApproved = true;
            
            emit ProposalExecuted(msg.sender,_proposalId);

        }else if(proposal.votesAgainst > proposal.votesFor){
            //Proposal rejected
            proposal.executed = true;
            proposal.isApproved =false;

            emit ProposalExecuted(msg.sender,_proposalId);
        }
    }




}