import sys
from pathlib import Path
import sqlite3
import uuid
import logging
from datetime import datetime

# Add the project root to Python path
project_root = Path(__file__).resolve().parent.parent
sys.path.append(str(project_root))

from app.utils.db.models import Base, SubscriptionStatus
from app.utils.db import get_db_path, get_session
from sqlalchemy import create_engine

logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

def backup_database():
    """Create a backup of the existing database"""
    db_path = get_db_path()
    if not db_path.exists():
        logger.info("No existing database found, skipping backup")
        return
    
    backup_path = db_path.parent / f"{db_path.stem}_backup_{datetime.now().strftime('%Y%m%d_%H%M%S')}{db_path.suffix}"
    db_path.rename(backup_path)
    logger.info(f"Created database backup at {backup_path}")
    return backup_path

def migrate_database():
    """Perform database migration"""
    try:
        # Create backup
        backup_path = backup_database()
        
        # Initialize new database
        engine = create_engine(f"sqlite:///{get_db_path()}")
        Base.metadata.create_all(engine)
        
        # If there's an old database, migrate the data
        if backup_path and backup_path.exists():
            logger.info("Migrating data from old database...")
            
            # Connect to old database
            old_conn = sqlite3.connect(backup_path)
            old_cursor = old_conn.cursor()
            
            # Get schema information
            old_cursor.execute("SELECT sql FROM sqlite_master WHERE type='table'")
            old_schema = old_cursor.fetchall()
            logger.info("Old database schema:")
            for table in old_schema:
                logger.info(table[0])
            
            with get_session() as session:
                try:
                    # Start transaction
                    session.begin()
                    
                    # Migrate users - note we only use user_id now
                    logger.info("Migrating users...")
                    old_cursor.execute("SELECT id, user_id, created_at FROM users")
                    users = old_cursor.fetchall()
                    user_id_map = {}  # Map old IDs to new UUIDs
                    
                    for old_id, user_id, created_at in users:
                        user_id_map[old_id] = user_id  # Keep the same user_id
                        session.execute(
                            "INSERT INTO users (user_id, created_at) VALUES (?, ?)",
                            [user_id, created_at or datetime.utcnow()]
                        )
                    
                    # Migrate subscriptions
                    logger.info("Migrating subscriptions...")
                    old_cursor.execute("""
                        SELECT id, user_id, invoice_id, public_key, start_time, 
                               expiry_time, status, warning_sent, assigned_ip
                        FROM subscriptions
                    """)
                    subscriptions = old_cursor.fetchall()
                    
                    for sub in subscriptions:
                        old_id, old_user_id, invoice_id, public_key, start_time, \
                        expiry_time, status, warning_sent, assigned_ip = sub
                        if old_user_id in user_id_map:
                            session.execute("""
                                INSERT INTO subscriptions 
                                (user_id, invoice_id, public_key, start_time, expiry_time, 
                                 status, warning_sent, assigned_ip)
                                VALUES (?, ?, ?, ?, ?, ?, ?, ?)
                            """, [
                                old_user_id,  # Use the original user_id
                                invoice_id,
                                public_key,
                                start_time,
                                expiry_time,
                                status,
                                warning_sent,
                                assigned_ip
                            ])
                    
                    # Migrate payments
                    logger.info("Migrating payments...")
                    old_cursor.execute("""
                        SELECT user_id, subscription_id, invoice_id, amount, timestamp
                        FROM payments
                    """)
                    payments = old_cursor.fetchall()
                    
                    for payment in payments:
                        old_user_id, sub_id, invoice_id, amount, timestamp = payment
                        if old_user_id in user_id_map:
                            session.execute("""
                                INSERT INTO payments 
                                (user_id, subscription_id, invoice_id, amount, timestamp)
                                VALUES (?, ?, ?, ?, ?)
                            """, [
                                old_user_id,  # Use the original user_id
                                sub_id,
                                invoice_id,
                                amount,
                                timestamp
                            ])
                    
                    # Commit transaction
                    session.commit()
                    logger.info("Migration completed successfully")
                    
                except Exception as e:
                    session.rollback()
                    logger.error(f"Migration failed: {str(e)}")
                    raise
                
            old_conn.close()
            
        else:
            logger.info("No existing database to migrate")
            
    except Exception as e:
        logger.error(f"Migration failed: {str(e)}")
        raise

if __name__ == '__main__':
    try:
        migrate_database()
    except Exception as e:
        logger.error(f"Migration failed: {str(e)}")
        sys.exit(1)