from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
from sqlalchemy.ext.declarative import declarative_base
import os
from dotenv import load_dotenv

load_dotenv()

# Get database URL from environment with SQLite fallback for development
DATABASE_URL = os.getenv("DATABASE_URL")

if not DATABASE_URL:
    # Default to SQLite for development if no PostgreSQL URL is provided
    DATABASE_URL = "sqlite:///./product_tracker.db"
    print("🔄 Using SQLite database for development")
else:
    print(f"🐘 Using PostgreSQL database")

# Configure engine based on database type
if DATABASE_URL.startswith("sqlite"):
    engine = create_engine(
        DATABASE_URL, 
        connect_args={"check_same_thread": False}  # Needed for SQLite
    )
else:
    engine = create_engine(DATABASE_URL)

SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)

Base = declarative_base()

# Dependency to get database session
def get_db():
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()