Command-Line To-Do App

Here's a functional starting version of your app. Copy it to your local Python editor and run it.

import json
from datetime import datetime

class Task:
    def __init__(self, title, priority="Medium", category="General", completed=False, created=None, due=None):
        self.title = title
        self.priority = priority
        self.category = category
        self.completed = completed
        self.created = created or datetime.now().strftime("%Y-%m-%d %H:%M")
        self.due = due

    def mark_done(self):
        self.completed = True

    def to_dict(self):
        return self.__dict__

class TodoApp:
    def __init__(self, filename="tasks.json"):
        self.filename = filename
        self.tasks = self.load_tasks()

    def load_tasks(self):
        try:
            with open(self.filename, "r") as f:
                data = json.load(f)
                return [Task(**t) for t in data]
        except (FileNotFoundError, json.JSONDecodeError):
            return []

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

    def add_task(self):
        title = input("Task title: ")
        if not title.strip():
            print("❌ Title cannot be empty.")
            return
        priority = input("Priority (High/Medium/Low): ") or "Medium"
        category = input("Category: ") or "General"
        due = input("Due date (YYYY-MM-DD, optional): ") or None
        task = Task(title, priority, category, False, None, due)
        self.tasks.append(task)
        self.save_tasks()
        print(f"✅ Task '{title}' added.")

    def list_tasks(self):
        if not self.tasks:
            print("📭 No tasks found.")
            return
        for i, t in enumerate(self.tasks, 1):
            status = "✔️" if t.completed else "❌"
            print(f"{i}. {t.title} [{t.priority}] ({t.category}) - {status}")

    def mark_complete(self):
        self.list_tasks()
        try:
            index = int(input("Enter task number to mark complete: "))
            self.tasks[index-1].mark_done()
            self.save_tasks()
            print("✅ Task marked complete!")
        except (ValueError, IndexError):
            print("❌ Invalid selection.")

    def delete_task(self):
        self.list_tasks()
        try:
            index = int(input("Enter task number to delete: "))
            task = self.tasks.pop(index-1)
            self.save_tasks()
            print(f"🗑️ Deleted '{task.title}'.")
        except (ValueError, IndexError):
            print("❌ Invalid number.")

    def search_tasks(self):
        term = input("Search keyword: ").lower()
        results = [t for t in self.tasks if term in t.title.lower() or term in t.category.lower()]
        if results:
            print(f"🔍 Found {len(results)} result(s):")
            for t in results:
                print(f"- {t.title} ({t.category}) [{t.priority}]")
        else:
            print("No matches found.")

    def menu(self):
        while True:
            print("
--- TO-DO MENU ---")
            print("1. Add Task")
            print("2. List Tasks")
            print("3. Mark Complete")
            print("4. Delete Task")
            print("5. Search")
            print("6. Exit")
            choice = input("Choose option: ")

            if choice == "1": self.add_task()
            elif choice == "2": self.list_tasks()
            elif choice == "3": self.mark_complete()
            elif choice == "4": self.delete_task()
            elif choice == "5": self.search_tasks()
            elif choice == "6":
                print("👋 Goodbye!")
                break
            else:
                print("❌ Invalid choice.")
                
if __name__ == "__main__":
    TodoApp().menu()

This demo version shows the core functionality without user input (browser limitation):

import json
from datetime import datetime

class Task:
    def __init__(self, title, priority="Medium", category="General", completed=False):
        self.title = title
        self.priority = priority
        self.category = category
        self.completed = completed
        self.created = datetime.now().strftime("%Y-%m-%d %H:%M")

    def mark_done(self):
        self.completed = True

    def __str__(self):
        status = "✔️" if self.completed else "❌"
        return f"{self.title} [{self
...

--- TO-DO MENU ---
1. Add Task
2. List Tasks
3. Mark Complete
4. Delete Task
5. Search
6. Exit
Choose option: 1
Task title: Study Python
Priority: High
Category: Study
✅ Task 'Study Python' added.

To evolve this into a professional-level tool, start introducing modular architecture and optional GUI.

todo/
 ┣ main.py
 ┣ models.py (Task class)
 ┣ storage.py (save/load)
 ┣ utils.py (helpers)
 ┗ menu.py

python todo.py --add "Buy groceries"
python todo.py --list

import argparse
parser = argparse.ArgumentParser()
parser.add_argument("--add")
args = parser.parse_args()

import sqlite3
conn = sqlite3.connect("tasks.db")

• • Use Async I/O: Replace normal file I/O with asyncio + aiofiles for instant responsiveness.
• • Add Unit Tests: Write automated pytest cases for each method (add_task, delete_task, etc.).
• • Implement Logging System: Use logging module for detailed app logs instead of prints.
• • Track Time Spent: Add start/stop timestamps for time management reports.
• • Command History: Store user actions in a log file to undo/redo actions.
• • Versioning: Auto-save task versions every edit like a lightweight Git system.
• • REST API: Convert into Flask REST API (backend) so frontends or other devices can sync tasks.
• • Voice Commands: Integrate speech_recognition to add tasks using microphone.
• • Cross-Platform Installer: Bundle into an .exe or .app using PyInstaller or cx_Freeze.
• • Cloud-Based Dashboard: Deploy to web (Render / Railway / Supabase) and manage via browser.
• • Machine Learning Add-On: Predict overdue likelihood or categorize automatically using simple models (e.g., scikit-learn).

1. Start with the base version above and test all functions.
2. Add enhancements one by one (don't jump straight to everything).
3. Learn to debug using print/logging and handle exceptions gracefully.
4. Refactor into modular files for easier maintenance.
5. Add small features like reminders and category filters first.
6. Document your app with a README, screenshots, and usage examples.
7. Push your finished project to GitHub or Replit and include in your portfolio or CV.

Each new feature is a learning milestone — by finishing this project, you'll understand how real developers structure, persist, and maintain applications.