# backend/core/db_utils.py

from sqlalchemy import insert as sa_insert
from sqlalchemy.dialects.postgresql import insert as pg_insert
from core.db import engine

_IS_PG = engine.url.get_backend_name().startswith("postgres")

def upsert(
    tbl,
    insert_values: dict,
    conflict_cols: list[str],
    update_values: dict | None = None,
):

    if _IS_PG:
        stmt = (
            pg_insert(tbl)
            .values(**insert_values)
            .on_conflict_do_update(
                index_elements=conflict_cols,
                set_=update_values or insert_values,
            )
        )
    else:
        stmt = (
            sa_insert(tbl)
            .values(**insert_values)
            .prefix_with("OR REPLACE")  # SQLite
        )
    return stmt