import sqlite3
from hashlib import sha256

# ایجاد و اتصال به دیتابیس
def create_database():
    conn = sqlite3.connect("user_database.db")
    cursor = conn.cursor()
    # ایجاد جدول کاربران (اگر وجود ندارد)
    cursor.execute("""
        CREATE TABLE IF NOT EXISTS users (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            username TEXT UNIQUE NOT NULL,
            password TEXT NOT NULL
        )
    """)
    conn.commit()
    conn.close()

# ثبت‌نام کاربر
def register_user(username, password):
    conn = sqlite3.connect("user_database.db")
    cursor = conn.cursor()
    try:
        hashed_password = sha256(password.encode()).hexdigest()  # هش کردن رمز عبور
        cursor.execute("INSERT INTO users (username, password) VALUES (?, ?)", (username, hashed_password))
        conn.commit()
        print("User registered successfully!")
    except sqlite3.IntegrityError:
        print("Error: Username already exists.")
    finally:
        conn.close()

# بررسی اطلاعات ورود کاربر
def login_user(username, password):
    conn = sqlite3.connect("user_database.db")
    cursor = conn.cursor()
    hashed_password = sha256(password.encode()).hexdigest()  # هش کردن رمز عبور
    cursor.execute("SELECT * FROM users WHERE username = ? AND password = ?", (username, hashed_password))
    user = cursor.fetchone()
    conn.close()
    if user:
        print(f"Welcome, {username}!")
    else:
        print("Invalid username or password.")

# منوی اصلی
def main():
    create_database()
    while True:
        print("\n1. Register")
        print("2. Login")
        print("3. Exit")
        choice = input("Choose an option: ")
        
        if choice == "1":
            username = input("Enter username: ")
            password = input("Enter password: ")
            register_user(username, password)
        elif choice == "2":
            username = input("Enter username: ")
            password = input("Enter password: ")
            login_user(username, password)
        elif choice == "3":
            print("Exiting program.")
            break
        else:
            print("Invalid choice. Please try again.")

# اجرای برنامه
if __name__ == "__main__":
    main()

#---