import logging
import subprocess
import sys
from pathlib import Path

# Add the project root to the Python path
sys.path.insert(0, str(Path(__file__).resolve().parent.parent.parent))

from sqlalchemy import create_engine, inspect, text

from app.core.config import settings
from app.core.database import SessionLocal
from app.core.security import get_password_hash
from app.models.user import User, UserRole

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

def run_migrations():
    """Run Alembic migrations to create or upgrade database schema."""
    try:
        logger.info("Running database migrations...")
        result = subprocess.run(
            ["alembic", "upgrade", "head"],
            check=True,
            capture_output=True,
            text=True
        )
        
        if result.stdout:
            logger.info(f"Migration output: {result.stdout}")
        
        if result.stderr:
            if "table users already exists" in result.stderr.lower():
                logger.info("Tables already exist. This is normal for existing databases.")
                return True
            else:
                logger.warning(f"Migration warnings: {result.stderr}")
        
        logger.info("Database migration completed successfully")
        return True
    except subprocess.CalledProcessError as e:
        logger.error("Database migration failed")
        logger.error(f"Exit code: {e.returncode}")
        logger.error(f"stdout: {e.stdout}")
        logger.error(f"stderr: {e.stderr}")
        
        # Don't fail if tables already exist
        if e.stderr and "table users already exists" in e.stderr.lower():
            logger.info("Tables already exist. Continuing with initialization...")
            return True
            
        return False

def check_db_tables():
    """Check if database tables already exist."""
    try:
        engine = create_engine(settings.SQLALCHEMY_DATABASE_URL)
        inspector = inspect(engine)
        # Get list of all tables
        tables = inspector.get_table_names()
        return len(tables) > 0, tables
    except Exception as e:
        logger.error(f"Error checking database tables: {e}")
        return False, []

def init_db():
    """Initialize the database with required tables and initial admin user."""
    try:
        # Create database directory if it doesn't exist
        settings.DB_DIR.mkdir(parents=True, exist_ok=True)
        
        # Check if tables already exist
        tables_exist, existing_tables = check_db_tables()
        logger.info(f"Found {len(existing_tables)} existing tables: {', '.join(existing_tables) if existing_tables else 'none'}")
        
        # Run migrations regardless, our updated script is idempotent and will handle existing tables
        if not run_migrations():
            logger.error("Failed to create database schema.")
            return False

        # Create an admin user
        db = SessionLocal()

        # Check if admin user already exists
        existing_admin = db.query(User).filter(User.email == settings.FIRST_SUPERUSER_EMAIL).first()

        if not existing_admin:
            logger.info("Creating initial admin user...")
            admin_user = User(
                email=settings.FIRST_SUPERUSER_EMAIL,
                hashed_password=get_password_hash(settings.FIRST_SUPERUSER_PASSWORD),
                is_active=True,
                role=UserRole.ADMIN,
                first_name="Admin",
                last_name="User",
                email_verified=True
            )
            db.add(admin_user)
            db.commit()
            logger.info(f"Admin user created with email: {settings.FIRST_SUPERUSER_EMAIL}")
        else:
            logger.info("Admin user already exists")

        db.close()
        logger.info("Database initialization completed successfully")
        return True

    except Exception as e:
        logger.error(f"Error initializing database: {e}")
        raise

if __name__ == "__main__":
    logger.info("Creating initial database tables and admin user")
    init_db()
    logger.info("Initial data created")