"""
Database module for the application.
"""

from flask_sqlalchemy import SQLAlchemy
from sqlalchemy import MetaData

# Define naming convention for constraints
convention = {
    "ix": 'ix_%(column_0_label)s',
    "uq": "uq_%(table_name)s_%(column_0_name)s",
    "ck": "ck_%(table_name)s_%(constraint_name)s",
    "fk": "fk_%(table_name)s_%(column_0_name)s_%(referred_table_name)s",
    "pk": "pk_%(table_name)s"
}

# Create SQLAlchemy instance with naming convention
db = SQLAlchemy(metadata=MetaData(naming_convention=convention))

def init_app(app):
    """
    Initialize the database with the Flask application.

    Args:
        app: Flask application instance.
    """
    db.init_app(app)

    # Only initialize database if configured to do so
    if app.config.get('INITIALIZE_DATABASE', False):
        # Import models to ensure they are registered with SQLAlchemy
        from app.models import user, chat, document

        # Create tables if they don't exist
        with app.app_context():
            db.create_all()