app.py

from flask import Flask, render_template, request, redirect, session
import sqlite3

app = Flask(__name__)
app.secret_key = "secret123"

# ---------- DB INIT ----------
def init_db():
    conn = sqlite3.connect('tasks.db')
    c = conn.cursor()

    c.execute('''
        CREATE TABLE IF NOT EXISTS users (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            username TEXT UNIQUE,
            password TEXT
        )
    ''')

    c.execute('''
        CREATE TABLE IF NOT EXISTS tasks (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            task TEXT,
            user_id INTEGER,
            is_deleted INTEGER DEFAULT 0,
            due_date TEXT,
            is_done INTEGER DEFAULT 0
        )
    ''')

    conn.commit()
    conn.close()

init_db()

# ---------- HOME ----------
@app.route('/')
def home():
    if 'user_id' not in session:
        return redirect('/login')

    conn = sqlite3.connect('tasks.db')
    c = conn.cursor()

    c.execute("SELECT * FROM tasks WHERE user_id=? AND is_deleted=0",
              (session['user_id'],))
    data = c.fetchall()

    c.execute("SELECT * FROM tasks WHERE user_id=? AND is_deleted=1",
              (session['user_id'],))
    deleted_data = c.fetchall()

    tasks = [
        {"id": r[0], "task": r[1], "due_date": r[4], "done": r[5]}
        for r in data
    ]

    deleted_tasks = [
        {"id": r[0], "task": r[1], "due_date": r[4]}
        for r in deleted_data
    ]

    conn.close()

    return render_template(
        "index.html",
        tasks=tasks,
        deleted_tasks=deleted_tasks,
        total=len(tasks),
        deleted=len(deleted_tasks)
    )

# ---------- REGISTER ----------
@app.route('/register', methods=['GET', 'POST'])
def register():
    if request.method == 'POST':
        username = request.form['username']
        password = request.form['password']

        conn = sqlite3.connect('tasks.db')
        c = conn.cursor()

        try:
            c.execute("INSERT INTO users (username, password) VALUES (?,?)",
                      (username, password))
            conn.commit()
        except:
            conn.close()
            return "User already exists"

        conn.close()
        return redirect('/login')

    return render_template('register.html')

# ---------- LOGIN ----------
@app.route('/login', methods=['GET', 'POST'])
def login():
    if request.method == 'POST':
        username = request.form['username']
        password = request.form['password']

        conn = sqlite3.connect('tasks.db')
        c = conn.cursor()

        c.execute("SELECT * FROM users WHERE username=? AND password=?",
                  (username, password))

        user = c.fetchone()
        conn.close()

        if user:
            session['user_id'] = user[0]
            return redirect('/')
        else:
            return "Invalid credentials"

    return render_template('login.html')

# ---------- LOGOUT ----------
@app.route('/logout')
def logout():
    session.pop('user_id', None)
    return redirect('/login')

# ---------- ADD TASK ----------
@app.route('/add', methods=['POST'])
def add_task():
    if 'user_id' not in session:
        return redirect('/login')

    task = request.form.get('task')
    due_date = request.form.get('due_date')

    conn = sqlite3.connect('tasks.db')
    c = conn.cursor()

    c.execute("INSERT INTO tasks (task, user_id, due_date) VALUES (?,?,?)",
              (task, session['user_id'], due_date))

    conn.commit()
    conn.close()

    return redirect('/')

# ---------- DELETE ----------
@app.route('/delete/<int:id>')
def delete_task(id):
    if 'user_id' not in session:
        return redirect('/login')

    conn = sqlite3.connect('tasks.db')
    c = conn.cursor()

    c.execute("UPDATE tasks SET is_deleted=1 WHERE id=? AND user_id=?",
              (id, session['user_id']))

    conn.commit()
    conn.close()

    return redirect('/')

# ---------- RESTORE ----------
@app.route('/restore/<int:id>')
def restore_task(id):
    if 'user_id' not in session:
        return redirect('/login')

    conn = sqlite3.connect('tasks.db')
    c = conn.cursor()

    c.execute("UPDATE tasks SET is_deleted=0 WHERE id=? AND user_id=?",
              (id, session['user_id']))

    conn.commit()
    conn.close()

    return redirect('/')

# ---------- DONE ----------
@app.route('/done/<int:id>')
def done_task(id):
    if 'user_id' not in session:
        return redirect('/login')

    conn = sqlite3.connect('tasks.db')
    c = conn.cursor()

    c.execute("UPDATE tasks SET is_done=1 WHERE id=? AND user_id=?",
              (id, session['user_id']))

    conn.commit()
    conn.close()

    return redirect('/')

# ---------- EMPTY TRASH ----------
@app.route('/empty-trash')
def empty_trash():
    if 'user_id' not in session:
        return redirect('/login')

    conn = sqlite3.connect('tasks.db')
    c = conn.cursor()

    c.execute("DELETE FROM tasks WHERE user_id=? AND is_deleted=1",
              (session['user_id'],))

    conn.commit()
    conn.close()

    return redirect('/')

# ---------- MAIN ----------
if __name__ == '__main__':
    app.run(debug=True)