"""QueryExecutor — dispatches retrieval results to the appropriate executor by source_type."""

import asyncio

from sqlalchemy.ext.asyncio import AsyncSession

from src.middlewares.logging import get_logger
from src.query.base import QueryResult
from src.query.executors.db_executor import db_executor
from src.query.executors.tabular import tabular_executor
from src.rag.base import RetrievalResult

logger = get_logger("query_executor")


class QueryExecutor:
    async def execute(
        self,
        results: list[RetrievalResult],
        user_id: str,
        db: AsyncSession,
        question: str,
        limit: int = 100,
    ) -> list[QueryResult]:
        db_results = [r for r in results if r.source_type == "database"]
        tabular_results = [
            r for r in results
            if r.source_type == "document"
            and r.metadata.get("data", {}).get("file_type") in ("csv", "xlsx")
        ]

        async def _empty() -> list[QueryResult]:
            return []

        batches = await asyncio.gather(
            db_executor.execute(db_results, user_id, db, question, limit) if db_results else _empty(),
            tabular_executor.execute(tabular_results, user_id, db, question, limit) if tabular_results else _empty(),
            return_exceptions=True,
        )

        query_results: list[QueryResult] = []
        for batch in batches:
            if isinstance(batch, Exception):
                logger.error("executor failed", error=str(batch))
                continue
            query_results.extend(batch)

        logger.info("query execution complete", total=len(query_results))
        return query_results


query_executor = QueryExecutor()