"""Base repository with common DB helpers."""
from __future__ import annotations

from sqlalchemy import text
from sqlalchemy.engine import Connection


class BaseRepository:
    def __init__(self, db: Connection):
        self._db = db

    def _execute(self, query: str, params: dict | None = None):
        return self._db.execute(text(query), params or {})

    def _fetchone(self, query: str, params: dict | None = None) -> dict | None:
        row = self._db.execute(text(query), params or {}).fetchone()
        if row is None:
            return None
        return dict(row._mapping)

    def _fetchall(self, query: str, params: dict | None = None) -> list[dict]:
        rows = self._db.execute(text(query), params or {}).fetchall()
        return [dict(r._mapping) for r in rows]

    def _lastrowid(self, query: str, params: dict | None = None) -> int:
        result = self._db.execute(text(query), params or {})
        return result.lastrowid