vote.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.7;

contract ElectionVote {

    address public owner;
    mapping(address => bool) adminLookup;
    Candidate[] candidateLookup;
    mapping(address => bytes32) vouter;

    uint startDate = 1644883200; // February 15, 2022 12:00:00 AM
    uint endDate = 1645315200; // February 20, 2022 12:00:00 AM

    struct CandidateDetail {
        string firstName;
        string lastName;
        uint8 age;
        string gender;
        string description;
        string imageURL;
    }

    struct Candidate {
        bytes32 id;
        CandidateDetail detail;
        uint voteCount;
    }

    constructor() {
        owner = msg.sender;
        adminLookup[owner] = true;
    }

    modifier onlyOwner() {
        require(adminLookup[msg.sender] == true, "this function for only admin");
        _;
    }

    function addAdmin(address _admin) public onlyOwner {
        require(adminLookup[_admin] == false, "this address is admin already exists");
        adminLookup[_admin] = true;
    }

    function removeAdmin(address _admin) public {
        require(_admin != owner, "you can't remove deployer");
        require(adminLookup[_admin] == true, "this address is not admin yet");
        adminLookup[_admin] = false;
    }

    function addCandidate(CandidateDetail memory detail) public onlyOwner {
        require(block.timestamp < startDate, "this functiaon can call before start date");
        bytes32 id = keccak256(abi.encodePacked(block.timestamp, candidateLookup.length + 1));
        candidateLookup.push(Candidate(id, detail, 0));
    }

    function updateCandidate(bytes32 id, CandidateDetail memory detail) public onlyOwner {
        require(block.timestamp < startDate, "this functiaon can call before start date");
        uint index = findIndexById(id);
        candidateLookup[index].detail = detail;
    }

    function getCandidates() public view returns(Candidate[] memory) {
        return candidateLookup;
    }

    function vote(bytes32 candidateId) public {
        require(block.timestamp >= startDate && block.timestamp <= endDate, "not availble date to voting");
        require(msg.sender != address(0), "address invalid");
        require(vouter[msg.sender] == bytes32(0), "you're have voited already");
        uint index = findIndexById(candidateId);
        candidateLookup[index].voteCount++;
        vouter[msg.sender] = candidateId;
    }

    function getWinner() public view returns(Candidate memory) {
        require(block.timestamp > endDate, "this function cam call after end date");
        return getMaxVote();
    }

    function getMaxVote() public view returns (Candidate memory){
        uint index = 0;
        uint max = candidateLookup[index].voteCount;
        for(uint i = 0; i < candidateLookup.length; i++) {
            if (candidateLookup[i].voteCount > max) {
                max = candidateLookup[i].voteCount;
                index = i;
            }
        }
        return candidateLookup[index];
    }

    function findIndexById(bytes32 id) private view returns(uint)  {
        for(uint i = 0; i < candidateLookup.length; i++) {
            if (candidateLookup[i].id == id) {
                return i;
            }
        }
        revert("not found candidate");
    }
}