task_manager.py

import json
import os
import sys

TASK_FILE = 'tasks.json'

def load_tasks():
    if not os.path.exists(TASK_FILE):
        return []
    with open(TASK_FILE, 'r') as f:
        return json.load(f)

def save_tasks(tasks):
    with open(TASK_FILE, 'w') as f:
        json.dump(tasks, f, indent=2)

def add_task(title):
    tasks = load_tasks()
    tasks.append({"title": title, "done": False})
    save_tasks(tasks)
    print(f"Added task: {title}")

def list_tasks():
    tasks = load_tasks()
    for i, task in enumerate(tasks):
        status = "✓" if task["done"] else "✗"
        print(f"{i+1}. [{status}] {task['title']}")

def complete_task(index):
    tasks = load_tasks()
    try:
        tasks[index - 1]["done"] = True
        save_tasks(tasks)
        print("Task marked as complete.")
    except IndexError:
        print("Invalid task number.")

if __name__ == "__main__":
    if len(sys.argv) < 2:
        print("Usage: python task_manager.py [add/list/complete] [task]")
    elif sys.argv[1] == "add":
        add_task(" ".join(sys.argv[2:]))
    elif sys.argv[1] == "list":
        list_tasks()
    elif sys.argv[1] == "complete":
        complete_task(int(sys.argv[2]))
    else:
        print("Unknown command.")