smart-city-gov.sol

/* Author : Santhosh Reddy */

//SPDX-License-Identifier: MIT
pragma solidity 0.8.*;

contract smartCityGov {

  /* All required properties (variable, structs, mappings,
  enums, events and modifiers) */
  
  address addr = 0x5B38Da6a701c568545dCfcB03FcB875f56beddC4;
  address payable public mayor = payable(addr);

  address adminAddr = 0x5B38Da6a701c568545dCfcB03FcB875f56beddC4;
  address public aadharAdmin = payable(adminAddr);
  
  uint8 public population;
  uint8 public totalTaxTxs;
  uint8 public totalActivities;
  
  function treasury() public view returns(uint) {
    return address(this).balance;
  }

  struct person {
    string name;
    uint8 age;
    uint256 tax;
  }
  mapping(address => person) citizens;

  struct activity {
    string title;
    string description;
    uint32 funds;
    uint8 upvotes;
    uint8 downvotes;
    address[] voters;
    activityStatus status;
    uint256 time;
  }
  mapping(uint8 => activity) activities;

  enum activityStatus{pending, approved, failed}

  event taxPayed(address name, uint256 amount);

  event voted(string activityTitle, address citizen);

  event activityProposedOrApproved(uint8 id);

  modifier onlyMayor() {
    require (msg.sender == mayor, "You aren't the mayor");
    _;
  }
  
  modifier onlyCitizen(address addrs) {
    require (citizens[addrs].age != 0, "You aren't a citizen of this city");
    _;
  }
  
  modifier onlyAadharAdmin() {
    require (msg.sender == aadharAdmin, "You aren't the aadharAdmin of this city");
    _;
  }

  modifier toVote(uint8 id) {
    bool a = true;
    for(uint8 i=0; i<activities[id].voters.length; i++) {
    if(activities[id].voters[i]==msg.sender) {
    a = false;
    }
    }
    require(a == true, "You have already voted this activity");
    _;
  }

  modifier approved(uint8 id) {
    require(block.timestamp - activities[id].time > 86400, "The voting time period hasn't completed");
    require(activities[id].upvotes > activities[id].downvotes, "The activity has failed due to majority of protesters");
    _;
    if(block.timestamp - activities[id].time > 86400 && activities[id].downvotes > activities[id].upvotes) {
    activities[id].status = activityStatus.failed;
    revert("The activity has failed due to majority of protesters");
    }
  }

  /* Functions of aadharAdmin */
  
  function addCitizen(address payable addrs, string memory name, uint8 age) public onlyAadharAdmin {
    require(citizens[addrs].age == 0);
    require(age != 0);
    citizens[addrs] = person(name, age, 0);
    population = population+1;
  }

  function readCitizen(address payable addrs) public view onlyAadharAdmin returns(person memory) {
    return citizens[addrs];
  }

  function removeCitizen(address payable  addrs) public onlyAadharAdmin {
    delete citizens[addrs];
    population = population-1;
  }

  /* Functions of Mayor */

  function proposeActivity(string memory title, string memory description,  uint32 funds) public onlyMayor {
    address[] memory voters;
    totalActivities++;
    activities[totalActivities] = activity(title, description, funds, 0, 0, voters, activityStatus.pending, block.timestamp);
    emit activityProposedOrApproved(totalActivities);
  }
  
  function getFunds(uint8 id) external approved(id) onlyMayor {
    activities[id].status = activityStatus.approved;
    payable(msg.sender).transfer(activities[id].funds);
  }

  function imposeTax(address citizen,uint256 tax) public onlyMayor {
    citizens[citizen].tax = citizens[citizen].tax + tax;
  }

  /* Functions of Citizens*/

  function payTax() public payable onlyCitizen(msg.sender) {
    require(msg.value <= citizens[msg.sender].tax);
    citizens[msg.sender].tax = citizens[msg.sender].tax - msg.value;
    emit taxPayed(msg.sender, msg.value);
    totalTaxTxs++;
    payable(msg.sender).transfer(msg.value);
  }

  function voteActivity(uint8 id, bool vote) public onlyCitizen(msg.sender) toVote(id) {
    activities[id].voters.push(msg.sender);
    if(vote == true) {
    activities[id].upvotes++;
    } else {
    activities[id].downvotes++;
    }
    emit voted(activities[id].title, msg.sender);
  }

  function myDetails() public view onlyCitizen(msg.sender) returns(person memory) {
    return citizens[msg.sender];
  }
  
  /* Public Functions */
    
  function getActivities(uint8 id) public view returns(activity memory) {
    return activities[id];
  }

}