TaskManager.py

import json
import os
from datetime import datetime

# Define a Task class
class Task:
    def __init__(self, title: str, description: str = "", due_date: str = None, completed: bool = False):
        self.title = title
        self.description = description
        self.due_date = due_date
        self.completed = completed

    def mark_completed(self):
        self.completed = True

    def to_dict(self):
        return {
            "title": self.title,
            "description": self.description,
            "due_date": self.due_date,
            "completed": self.completed
        }

    @staticmethod
    def from_dict(data):
        return Task(
            title=data.get("title"),
            description=data.get("description"),
            due_date=data.get("due_date"),
            completed=data.get("completed", False)
        )

# Task Manager class to handle a collection of tasks
class TaskManager:
    def __init__(self, filename="tasks.json"):
        self.filename = filename
        self.tasks = self.load_tasks()

    def add_task(self, task: Task):
        self.tasks.append(task)
        self.save_tasks()
        print(f"Task '{task.title}' added.")

    def remove_task(self, task_index: int):
        if 0 <= task_index < len(self.tasks):
            removed_task = self.tasks.pop(task_index)
            self.save_tasks()
            print(f"Task '{removed_task.title}' removed.")
        else:
            print("Invalid task index.")

    def list_tasks(self):
        if not self.tasks:
            print("No tasks available.")
            return
        for i, task in enumerate(self.tasks):
            status = "Done" if task.completed else "Pending"
            print(f"{i + 1}. {task.title} - {status}")
            if task.description:
                print(f"   Description: {task.description}")
            if task.due_date:
                print(f"   Due Date: {task.due_date}")

    def mark_task_completed(self, task_index: int):
        if 0 <= task_index < len(self.tasks):
            self.tasks[task_index].mark_completed()
            self.save_tasks()
            print(f"Task '{self.tasks[task_index].title}' marked as completed.")
        else:
            print("Invalid task index.")

    def save_tasks(self):
        with open(self.filename, "w") as f:
            json.dump([task.to_dict() for task in self.tasks], f, indent=4)

    def load_tasks(self):
        if not os.path.exists(self.filename):
            return []
        with open(self.filename, "r") as f:
            data = json.load(f)
            return [Task.from_dict(d) for d in data]

# Command-line interface
def main():
    manager = TaskManager()

    while True:
        print("
Task Manager")
        print("1. List Tasks")
        print("2. Add Task")
        print("3. Remove Task")
        print("4. Mark Task Completed")
        print("5. Exit")

        choice = input("Choose an option: ")

        if choice == "1":
            manager.list_tasks()
        elif choice == "2":
            title = input("Task title: ")
            description = input("Task description (optional): ")
            due_date = input("Due date (YYYY-MM-DD) (optional): ")
            manager.add_task(Task(title=title, description=description, due_date=due_date))
        elif choice == "3":
            index = int(input("Task index to remove: ")) - 1
            manager.remove_task(index)
        elif choice == "4":
            index = int(input("Task index to mark completed: ")) - 1
            manager.mark_task_completed(index)
        elif choice == "5":
            print("Exiting Task Manager. Goodbye!")
            break
        else:
            print("Invalid option. Please try again.")

if __name__ == "__main__":
    main()