Implementation of Mobile Theft Prevention Smart Contract in JavaScript and Solidity

MTP.js

const Web3 = require('web3');
const web3 = new Web3('http://localhost:8545'); // your Blockchain client endpoint

const contractAddress = '0x123456789...'; // your contract address
const abi = [/* Smart Contract ABI */]; // your contract ABI

const contract = new web3.eth.Contract(abi, contractAddress);

const isIMEIexist = {};
const isPhoneNumberexist = {};
const mapAPI = {};
const isIMEIlost = {};

function hash(value) {
  return web3.utils.keccak256(web3.eth.abi.encodeParameter('uint256', value));
}

async function addIMEI(IMEI, phoneNumber) {
  if (!isIMEIexist[hash(IMEI)] && !isPhoneNumberexist[hash(phoneNumber)]) {
    isIMEIexist[hash(IMEI)] = true;
    isPhoneNumberexist[hash(phoneNumber)] = true;
    mapAPI[web3.eth.defaultAccount][hash(phoneNumber)] = hash(IMEI);
    await contract.methods.addIMEI(IMEI, phoneNumber).send({ from: web3.eth.defaultAccount });
  }
}

async function activateLost(phoneNumber) {
  const IMEI = mapAPI[web3.eth.defaultAccount][hash(phoneNumber)];
  if (isIMEIexist[IMEI]) {
    isIMEIlost[IMEI] = true;
    await contract.methods.activateLost(phoneNumber).send({ from: web3.eth.defaultAccount });
  }
}

async function deactivateLost(phoneNumber) {
  const IMEI = mapAPI[web3.eth.defaultAccount][hash(phoneNumber)];
  if (isIMEIexist[IMEI]) {
    isIMEIlost[IMEI] = false;
    await contract.methods.deactivateLost(phoneNumber).send({ from: web3.eth.defaultAccount });
  }
}

async function changeIMEI(IMEI, phoneNumber, newIMEI) {
  if (isIMEIexist[hash(IMEI)] && isPhoneNumberexist[hash(phoneNumber)] && mapAPI[web3.eth.defaultAccount][hash(phoneNumber)] === hash(IMEI)) {
    mapAPI[web3.eth.defaultAccount][hash(phoneNumber)] = hash(newIMEI);
    isIMEIexist[hash(IMEI)] = false;
    if (!isIMEIexist[hash(newIMEI)]) {
      isIMEIexist[hash(newIMEI)] = true;
    }
    await contract.methods.changeIMEI(IMEI, phoneNumber, newIMEI).send({ from: web3.eth.defaultAccount });
  }
}

async function changePhoneNumber(IMEI, phoneNumber, newPhoneNumber) {
  if (isIMEIexist[hash(IMEI)] && isPhoneNumberexist[hash(phoneNumber)] && mapAPI[web3.eth.defaultAccount][hash(phoneNumber)] === hash(IMEI)) {
    mapAPI[web3.eth.defaultAccount][hash(phoneNumber)] = hash(0);
    mapAPI[web3.eth.defaultAccount][hash(newPhoneNumber)] = hash(IMEI);
    isPhoneNumberexist[hash(phoneNumber)] = false;
    await contract.methods.changePhoneNumber(IMEI, phoneNumber, newPhoneNumber).send({ from: web3.eth.defaultAccount });
  }
}

async function checkIMEI(IMEI) {
  return isIMEIlost[hash(IMEI)];
}

module.exports = {
  addIMEI,
  activateLost,
  deactivateLost,
  changeIMEI,
  changePhoneNumber,
  checkIMEI
};

MTP.sol

// SPDX-License-Identifier: MIT
pragma solidity 0.8.7;

contract MTP{
    mapping(bytes32=>bool) private isIMEIexist;
    mapping(bytes32=>bool) private isPhoneNumberexist;
    mapping(address=>mapping(bytes32=>bytes32)) private mapAPI;
    mapping(bytes32=>bool) private isIMEIlost;

    function hash(uint _value) private pure returns(bytes32){
        return keccak256(abi.encodePacked(_value));
    }

    function addIMEI(uint _IMEI, uint _phoneNumber) public{
        require(isIMEIexist[hash(_IMEI)] == false);
        require(isPhoneNumberexist[hash(_phoneNumber)] == false);
        isIMEIexist[hash(_IMEI)] = true;
        isPhoneNumberexist[hash(_phoneNumber)] = true;
        mapAPI[msg.sender][hash(_phoneNumber)] = hash(_IMEI);
    }

    function activateLost(uint _phoneNumber) public{
        require(isIMEIexist[mapAPI[msg.sender][hash(_phoneNumber)]] == true);
        isIMEIlost[mapAPI[msg.sender][hash(_phoneNumber)]] = true;
    }

    function deactivateLost(uint _phoneNumber) public{
        require(isIMEIexist[mapAPI[msg.sender][hash(_phoneNumber)]] == true);
        isIMEIlost[mapAPI[msg.sender][hash(_phoneNumber)]] = false;
    }

    function changeIMEI(uint _IMEI, uint _phoneNumber, uint _newIMEI) public{
        require(isIMEIexist[hash(_IMEI)] == true);
        require(isPhoneNumberexist[hash(_phoneNumber)] == true);
        require(mapAPI[msg.sender][hash(_phoneNumber)] == hash(_IMEI));
        mapAPI[msg.sender][hash(_phoneNumber)] = hash(_newIMEI);
        isIMEIexist[hash(_IMEI)] = false;
        if(isIMEIexist[hash(_newIMEI)] == false){
            isIMEIexist[hash(_IMEI)] = true;
        }
    }

    function changePhoneNumber(uint _IMEI, uint _phoneNumber, uint _newPhoneNumber) public{
        require(isIMEIexist[hash(_IMEI)] == true);
        require(isPhoneNumberexist[hash(_phoneNumber)] == true);
        require(mapAPI[msg.sender][hash(_phoneNumber)] == hash(_IMEI));
        mapAPI[msg.sender][hash(_phoneNumber)] = hash(uint(0));
        mapAPI[msg.sender][hash(_newPhoneNumber)] = hash(_IMEI);
        isPhoneNumberexist[hash(_phoneNumber)] = false;
    }

    function checkIMEI(uint _IMEI) public view returns(bool){
        return isIMEIlost[hash(_IMEI)];
    }

}