from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker

from app.core.config import settings

# Create SQLAlchemy engine
engine = create_engine(
    settings.SQLALCHEMY_DATABASE_URL,
    connect_args={"check_same_thread": False}
)

# Create SessionLocal class
SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)

# Create Base class for models
Base = declarative_base()

# Dependency for getting DB session
def get_db():
    """Dependency function that yields DB sessions.
    
    Yields:
        db: SQLAlchemy database session
    """
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()