"""Best-effort periodic full scans for the DeerFlow-local Wiki index."""

from __future__ import annotations

import asyncio
import logging
from collections.abc import Coroutine
from typing import Any

from fastapi import FastAPI

logger = logging.getLogger(__name__)


def spawn_local_wiki_index_job(app: FastAPI, coroutine: Coroutine[Any, Any, Any]) -> asyncio.Task:
    """Keep fire-and-forget index jobs strongly referenced until completion."""

    jobs: set[asyncio.Task] = getattr(app.state, "llmwiki_index_jobs", None)
    if jobs is None:
        jobs = set()
        app.state.llmwiki_index_jobs = jobs
    task = asyncio.create_task(coroutine)
    jobs.add(task)
    task.add_done_callback(jobs.discard)
    return task


async def _sync_once(app: FastAPI) -> None:
    service = getattr(app.state, "llmwiki_sync_service", None)
    mapping_store = getattr(app.state, "llmwiki_store", None)
    if service is None or mapping_store is None:
        return
    config = app.state.config.llmwiki.local_wiki_index
    mappings = [row for row in await mapping_store.list_visible("system", scope="all", is_admin=True) if row.get("wiki_index_enabled", True)]
    semaphore = asyncio.Semaphore(config.sync_concurrency)

    async def run(mapping):
        async with semaphore:
            try:
                await service.sync_mapping(mapping)
            except asyncio.CancelledError:
                raise
            except Exception:
                logger.warning("Periodic local Wiki sync failed mapping_id=%s", mapping.get("id"), exc_info=True)

    await asyncio.gather(*(run(mapping) for mapping in mappings))


async def local_wiki_index_scheduler_loop(app: FastAPI) -> None:
    interval = app.state.config.llmwiki.local_wiki_index.sync_interval_seconds
    logger.info(
        "Local Wiki auto-sync scheduler started; first scan is immediate, interval=%s seconds",
        interval,
    )
    while True:
        try:
            await _sync_once(app)
        except asyncio.CancelledError:
            raise
        except Exception:
            logger.exception("Local Wiki auto-sync scheduler tick failed (non-fatal)")
        await asyncio.sleep(interval)