from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker
from app.config import settings

import os
import platform

BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))

# Use /tmp on Linux (HF Spaces) to ensure write permissions
if platform.system() == "Linux":
    db_path = "/tmp/andesops.db"
else:
    db_path = os.path.join(BASE_DIR, "andesops.db")

default_db_path = f"sqlite:///{db_path}"
SQLALCHEMY_DATABASE_URL = settings.database_url or default_db_path

# SQLite specific config for FastAPI multi-threading
connect_args = {"check_same_thread": False} if SQLALCHEMY_DATABASE_URL.startswith("sqlite") else {}

engine = create_engine(
    SQLALCHEMY_DATABASE_URL, connect_args=connect_args
)
SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)

Base = declarative_base()

def get_db():
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()