from collections.abc import Generator

from sqlalchemy import create_engine
from sqlalchemy.orm import Session, declarative_base, sessionmaker

from admin_app.core.settings import get_admin_settings

# monta a conexão do banco administrativo e expõe get_admin_db_session(). Esse generator é o que alimenta as dependências FastAPI para repositórios e serviços.

settings = get_admin_settings()
admin_cloud_sql = settings.admin_db_cloud_sql_connection_name

if admin_cloud_sql:
    ADMIN_DATABASE_URL = (
        f"mysql+pymysql://{settings.admin_db_user}:{settings.admin_db_password}@/{settings.admin_db_name}"
        f"?unix_socket=/cloudsql/{admin_cloud_sql}"
    )
else:
    ADMIN_DATABASE_URL = (
        f"mysql+pymysql://{settings.admin_db_user}:{settings.admin_db_password}@"
        f"{settings.admin_db_host}:{settings.admin_db_port}/{settings.admin_db_name}"
    )

admin_engine = create_engine(
    ADMIN_DATABASE_URL,
    pool_pre_ping=True,
    connect_args={"connect_timeout": 5},
)

AdminSessionLocal = sessionmaker(
    autocommit=False,
    autoflush=False,
    bind=admin_engine,
)

AdminBase = declarative_base()


def get_admin_db_session() -> Generator[Session, None, None]:
    db = AdminSessionLocal()
    try:
        yield db
    finally:
        db.close()