from sqlalchemy import create_engine
from sqlalchemy.orm import DeclarativeBase, sessionmaker

from app.config import settings


def build_database_url() -> str:
    return (
        f"postgresql+psycopg://{settings.postgres_user}:"
        f"{settings.postgres_password}@{settings.postgres_host}:"
        f"{settings.postgres_port}/{settings.postgres_db}"
    )


DATABASE_URL = build_database_url()

engine = create_engine(DATABASE_URL, pool_pre_ping=True)

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


class Base(DeclarativeBase):
    pass


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