"""评测台：查询用户 segment 是否已完成回忆录 Phase1（topic_category 已写入）。"""

from __future__ import annotations

from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from app.features.conversation.models import Conversation, Segment
from app.features.conversation.ws.pipeline import background_runner
from app.features.evaluation.errors import (
    EvaluationBadRequestError,
    EvaluationNotFoundError,
)
from app.features.evaluation.schemas import MemoirPhase1ReadyOut, MemoirSubmitOut


class MemoirReadinessService:
    def __init__(self, db: AsyncSession) -> None:
        self._db = db

    async def memoir_phase1_ready_for_segments(
        self,
        *,
        conversation_id: str,
        segment_ids: list[str],
    ) -> MemoirPhase1ReadyOut:
        cid = (conversation_id or "").strip()
        if not cid:
            raise EvaluationBadRequestError("conversation_id is required")
        ids = [s.strip() for s in segment_ids if (s or "").strip()]
        if not ids:
            raise EvaluationBadRequestError("segment_ids is required")

        conv = await self._db.get(Conversation, cid)
        if not conv or conv.deleted_at is not None:
            raise EvaluationNotFoundError("conversation not found")

        stmt = select(Segment).where(
            Segment.id.in_(ids),
            Segment.conversation_id == cid,
        )
        result = await self._db.execute(stmt)
        rows = list(result.scalars().all())
        found_ids = {s.id for s in rows}
        missing = [i for i in ids if i not in found_ids]
        if missing:
            raise EvaluationBadRequestError(
                "segment not in conversation: " + ", ".join(missing[:5])
                + ("…" if len(missing) > 5 else "")
            )

        pending = [s.id for s in rows if s.topic_category is None]
        ready = len(pending) == 0
        return MemoirPhase1ReadyOut(
            ready=ready,
            checked_segment_ids=ids,
            pending_segment_ids=pending,
        )

    async def submit_memoir_phase1_for_conversation(
        self,
        *,
        conversation_id: str,
    ) -> MemoirSubmitOut:
        """本会话内尚待 Phase1 的 segment 合并提交 Celery（与对话结束 flush 语义对齐）。"""
        cid = (conversation_id or "").strip()
        if not cid:
            raise EvaluationBadRequestError("conversation_id is required")
        conv = await self._db.get(Conversation, cid)
        if not conv or conv.deleted_at is not None:
            raise EvaluationNotFoundError("conversation not found")
        uid = str(conv.user_id)
        stmt = (
            select(Segment.id)
            .where(
                Segment.conversation_id == cid,
                Segment.processed.is_(False),
                Segment.topic_category.is_(None),
            )
            .order_by(Segment.created_at.asc())
        )
        result = await self._db.execute(stmt)
        segment_ids = [str(i) for i in result.scalars().all()]
        if not segment_ids:
            return MemoirSubmitOut(
                conversation_id=cid,
                user_id=uid,
                segment_ids=[],
                celery_task_id=None,
            )
        task_id = await background_runner.flush_pending(
            uid, extra_segment_ids=segment_ids
        )
        return MemoirSubmitOut(
            conversation_id=cid,
            user_id=uid,
            segment_ids=segment_ids,
            celery_task_id=task_id,
        )