TodoList.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.7;

contract TodoList {

    struct Task {
        bytes32 id;
        string title;
        string description;
        bool mark;
    }

    mapping(address => Task[]) taskLookups;

   function create(string memory _title, string memory _description) public {
       bytes32 id = keccak256(abi.encodePacked(block.timestamp, 
                        taskLookups[msg.sender].length + 1)
                    );
       taskLookups[msg.sender].push(Task(id, _title, _description, false));
   }

   function getById(bytes32 id) public view returns(Task memory) {
       uint index = findIndexById(id);
       return taskLookups[msg.sender][index];
   }

   function getAll() public view returns(Task[] memory) {
       return taskLookups[msg.sender];
   }

   function marking(bytes32 id, bool status) public returns(bool) {
       uint index = findIndexById(id);
       taskLookups[msg.sender][index].mark = status;
       return true;
   }

   function remove(bytes32 id) public returns(bool) {
       uint index = findIndexById(id);
       taskLookups[msg.sender][index] = taskLookups[msg.sender][taskLookups[msg.sender].length - 1];
       taskLookups[msg.sender].pop();
       return true;
   }

   function update(bytes32 id, string memory title, string memory description) public {
       uint index = findIndexById(id);
       taskLookups[msg.sender][index].title = title;
       taskLookups[msg.sender][index].description = description;
   }

   function findIndexById(bytes32 id) private view returns(uint)  {
        Task[] memory tasks = taskLookups[msg.sender];
        for(uint i = 0; i < tasks.length; i++) {
            if (tasks[i].id == id) {
                return i;
            }
        }
        revert("not found item");
    }
}