import sqlite3
from datetime import datetime
import os

DB_FILE = "sms_app.db"

class DBHandler:
    def __init__(self, db_path=DB_FILE):
        self.db_path = db_path
        self._initialize_db()

    def _get_connection(self):
        return sqlite3.connect(self.db_path)

    def _initialize_db(self):
        with self._get_connection() as conn:
            cursor = conn.cursor()
            # Create contacts table
            cursor.execute('''
                CREATE TABLE IF NOT EXISTS contacts (
                    id INTEGER PRIMARY KEY AUTOINCREMENT,
                    name TEXT NOT NULL,
                    phone TEXT UNIQUE NOT NULL,
                    public_key TEXT
                )
            ''')
            # Create messages table
            cursor.execute('''
                CREATE TABLE IF NOT EXISTS messages (
                    id INTEGER PRIMARY KEY AUTOINCREMENT,
                    phone TEXT NOT NULL,
                    text TEXT NOT NULL,
                    date TEXT NOT NULL,
                    is_secure INTEGER NOT NULL,
                    status TEXT NOT NULL,
                    FOREIGN KEY(phone) REFERENCES contacts(phone)
                )
            ''')
            # Create settings table for our own keypair if needed (though usually we save keys to files)
            cursor.execute('''
                CREATE TABLE IF NOT EXISTS settings (
                    key TEXT PRIMARY KEY,
                    value TEXT
                )
            ''')
            conn.commit()

    # --- Contacts Methods ---
    def add_contact(self, name, phone, public_key=None):
        with self._get_connection() as conn:
            cursor = conn.cursor()
            try:
                cursor.execute('INSERT INTO contacts (name, phone, public_key) VALUES (?, ?, ?)',
                               (name, phone, public_key))
                conn.commit()
                return True
            except sqlite3.IntegrityError:
                return False # Phone number already exists

    def update_contact_key(self, phone, public_key):
        with self._get_connection() as conn:
            cursor = conn.cursor()
            cursor.execute('UPDATE contacts SET public_key = ? WHERE phone = ?', (public_key, phone))
            conn.commit()

    def get_contact(self, phone):
        with self._get_connection() as conn:
            cursor = conn.cursor()
            cursor.execute('SELECT name, phone, public_key FROM contacts WHERE phone = ?', (phone,))
            return cursor.fetchone()

    def get_all_contacts(self):
        with self._get_connection() as conn:
            cursor = conn.cursor()
            cursor.execute('SELECT name, phone, public_key FROM contacts')
            return cursor.fetchall()
            
    def set_contact_name_if_not_exists(self, phone, name):
         with self._get_connection() as conn:
            cursor = conn.cursor()
            cursor.execute('SELECT phone FROM contacts WHERE phone = ?', (phone,))
            if not cursor.fetchone():
                cursor.execute('INSERT INTO contacts (name, phone, public_key) VALUES (?, ?, ?)', (name, phone, None))
                conn.commit()

    # --- Messages Methods ---
    def add_message(self, phone, text, is_secure, status):
        date_str = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
        with self._get_connection() as conn:
            cursor = conn.cursor()
            cursor.execute('''
                INSERT INTO messages (phone, text, date, is_secure, status)
                VALUES (?, ?, ?, ?, ?)
            ''', (phone, text, date_str, int(is_secure), status))
            conn.commit()
            return cursor.lastrowid

    def get_messages_for_contact(self, phone):
        with self._get_connection() as conn:
            cursor = conn.cursor()
            cursor.execute('''
                SELECT id, phone, text, date, is_secure, status 
                FROM messages 
                WHERE phone = ? 
                ORDER BY date ASC
            ''', (phone,))
            return cursor.fetchall()

    def delete_message(self, msg_id):
        with self._get_connection() as conn:
            cursor = conn.cursor()
            cursor.execute('DELETE FROM messages WHERE id = ?', (msg_id,))
            conn.commit()

    # --- Settings Methods ---
    def get_setting(self, key):
         with self._get_connection() as conn:
            cursor = conn.cursor()
            cursor.execute('SELECT value FROM settings WHERE key = ?', (key,))
            row = cursor.fetchone()
            return row[0] if row else None

    def set_setting(self, key, value):
         with self._get_connection() as conn:
            cursor = conn.cursor()
            cursor.execute('INSERT OR REPLACE INTO settings (key, value) VALUES (?, ?)', (key, value))
            conn.commit()

if __name__ == "__main__":
    db = DBHandler("test_sms.db")
    db.add_contact("Alice", "+1234567890", "PUBLIC_KEY_CONTENT")
    db.add_message("+1234567890", "Hello Alice!", is_secure=False, status="sent")
    print("Database OK.")
    os.remove("test_sms.db")