"""Memory repository — MemorySource, MemoryChunk, MemoryFact, TimelineEvent data access."""

import uuid
from datetime import datetime, timedelta, timezone
from typing import TYPE_CHECKING

from sqlalchemy import delete, literal, or_, select, text, tuple_, update
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy.orm import Session

from app.features.memory.models import (
    MemoryChunk,
    MemoryCurationAction,
    MemoryFact,
    MemorySource,
    MemorySummary,
    TimelineEvent,
)

if TYPE_CHECKING:
    from app.ports.embedding import EmbeddingProvider


def _new_id() -> str:
    return str(uuid.uuid4())


def create_source_sync(
    session: Session,
    *,
    user_id: str,
    source_type: str,
    raw_text: str | None = None,
    conversation_id: str | None = None,
    captured_at: datetime | None = None,
) -> MemorySource:
    """Create a memory source (sync). Caller must commit."""
    source = MemorySource(
        id=_new_id(),
        user_id=user_id,
        source_type=source_type,
        raw_text=raw_text,
        conversation_id=conversation_id,
        captured_at=captured_at or datetime.now(timezone.utc),
    )
    session.add(source)
    return source


async def create_source(
    db: AsyncSession,
    *,
    user_id: str,
    source_type: str,
    raw_text: str | None = None,
    conversation_id: str | None = None,
    captured_at: datetime | None = None,
) -> MemorySource:
    """Create a memory source. Caller must commit."""
    source = MemorySource(
        id=_new_id(),
        user_id=user_id,
        source_type=source_type,
        raw_text=raw_text,
        conversation_id=conversation_id,
        captured_at=captured_at or datetime.now(timezone.utc),
    )
    db.add(source)
    return source


def create_chunk_sync(
    session: Session,
    *,
    source_id: str,
    user_id: str,
    content: str,
    chunk_index: int,
) -> MemoryChunk:
    """Create a memory chunk (sync). Caller must commit."""
    chunk = MemoryChunk(
        id=_new_id(),
        source_id=source_id,
        user_id=user_id,
        content=content,
        chunk_index=chunk_index,
    )
    session.add(chunk)
    return chunk


async def create_chunk(
    db: AsyncSession,
    *,
    source_id: str,
    user_id: str,
    content: str,
    chunk_index: int,
) -> MemoryChunk:
    """Create a memory chunk. Caller must commit."""
    chunk = MemoryChunk(
        id=_new_id(),
        source_id=source_id,
        user_id=user_id,
        content=content,
        chunk_index=chunk_index,
    )
    db.add(chunk)
    return chunk


def update_chunk_embedding_sync(
    session: Session, chunk_id: str, embedding: list[float]
) -> None:
    """Update chunk embedding (sync). Caller must commit."""
    chunk = session.get(MemoryChunk, chunk_id)
    if chunk:
        chunk.embedding = embedding


async def update_chunk_embedding(
    db: AsyncSession, chunk_id: str, embedding: list[float]
) -> None:
    """Update chunk embedding. Caller must commit."""
    chunk = await db.get(MemoryChunk, chunk_id)
    if chunk:
        chunk.embedding = embedding


async def get_chunks_by_ids(
    db: AsyncSession, chunk_ids: list[str]
) -> list[MemoryChunk]:
    """Fetch chunks by IDs."""
    if not chunk_ids:
        return []
    stmt = select(MemoryChunk).where(MemoryChunk.id.in_(chunk_ids))
    result = await db.execute(stmt)
    chunks = list(result.unique().scalars().all())
    order = {cid: i for i, cid in enumerate(chunk_ids)}
    return sorted(chunks, key=lambda c: order.get(c.id, 999))


async def get_facts_for_user(
    db: AsyncSession, user_id: str, limit: int = 20
) -> list[MemoryFact]:
    """Fetch recent facts for user."""
    stmt = (
        select(MemoryFact)
        .where(MemoryFact.user_id == user_id, MemoryFact.status == "confirmed")
        .order_by(MemoryFact.created_at.desc())
        .limit(limit)
    )
    result = await db.execute(stmt)
    return list(result.unique().scalars().all())


def get_facts_for_user_sync(
    session: Session, user_id: str, limit: int = 20
) -> list[MemoryFact]:
    stmt = (
        select(MemoryFact)
        .where(MemoryFact.user_id == user_id, MemoryFact.status == "confirmed")
        .order_by(MemoryFact.created_at.desc())
        .limit(limit)
    )
    return list(session.execute(stmt).unique().scalars().all())


def get_timeline_events_for_user_sync(
    session: Session, user_id: str, limit: int = 20
) -> list[TimelineEvent]:
    stmt = (
        select(TimelineEvent)
        .where(TimelineEvent.user_id == user_id)
        .order_by(
            TimelineEvent.event_year.desc().nullslast(), TimelineEvent.created_at.desc()
        )
        .limit(limit)
    )
    return list(session.execute(stmt).unique().scalars().all())


def search_facts_for_user_sync(
    session: Session, user_id: str, query: str, limit: int = 20
) -> list[MemoryFact]:
    from app.core.config import settings

    q = (query or "").strip()
    if not q:
        return get_facts_for_user_sync(session, user_id, limit)
    pat = f"%{q}%"
    stmt = (
        select(MemoryFact)
        .where(
            MemoryFact.user_id == user_id,
            MemoryFact.status == "confirmed",
            or_(MemoryFact.subject.ilike(pat), MemoryFact.predicate.ilike(pat)),
        )
        .order_by(MemoryFact.created_at.desc())
        .limit(limit)
    )
    rows = list(session.execute(stmt).unique().scalars().all())
    if rows:
        return rows
    if settings.memory_fact_search_use_recent_fallback:
        return get_facts_for_user_sync(session, user_id, limit)
    return []


async def search_facts_for_user_async(
    db: AsyncSession, user_id: str, query: str, limit: int = 20
) -> list[MemoryFact]:
    from app.core.config import settings

    q = (query or "").strip()
    if not q:
        return await get_facts_for_user(db, user_id=user_id, limit=limit)
    pat = f"%{q}%"
    stmt = (
        select(MemoryFact)
        .where(
            MemoryFact.user_id == user_id,
            MemoryFact.status == "confirmed",
            or_(MemoryFact.subject.ilike(pat), MemoryFact.predicate.ilike(pat)),
        )
        .order_by(MemoryFact.created_at.desc())
        .limit(limit)
    )
    result = await db.execute(stmt)
    rows = list(result.unique().scalars().all())
    if rows:
        return rows
    if settings.memory_fact_search_use_recent_fallback:
        return await get_facts_for_user(db, user_id=user_id, limit=limit)
    return []


def mark_facts_stale_for_excluded_chunk_sync(
    session: Session, *, user_id: str, chunk_id: str
) -> int:
    """
    Compaction 软排除 chunk 后：将与该 chunk 绑定的候选/已确认事实标为 stale，
    避免 derive-only 断言在失去原文支撑后仍作为权威 evidence。
    """
    stmt = (
        update(MemoryFact)
        .where(
            MemoryFact.user_id == user_id,
            MemoryFact.source_chunk_id == chunk_id,
            MemoryFact.status.in_(["confirmed", "candidate"]),
        )
        .values(status="stale")
    )
    res = session.execute(stmt)
    return int(res.rowcount or 0)


def search_timeline_events_for_user_sync(
    session: Session, user_id: str, query: str, limit: int = 20
) -> list[TimelineEvent]:
    q = (query or "").strip()
    if not q:
        return get_timeline_events_for_user_sync(session, user_id, limit)
    pat = f"%{q}%"
    stmt = (
        select(TimelineEvent)
        .where(
            TimelineEvent.user_id == user_id,
            or_(
                TimelineEvent.title.ilike(pat),
                TimelineEvent.description.ilike(pat),
            ),
        )
        .order_by(TimelineEvent.event_year.desc().nullslast())
        .limit(limit)
    )
    rows = list(session.execute(stmt).unique().scalars().all())
    if rows:
        return rows
    return get_timeline_events_for_user_sync(session, user_id, limit)


async def search_timeline_events_for_user_async(
    db: AsyncSession, user_id: str, query: str, limit: int = 20
) -> list[TimelineEvent]:
    q = (query or "").strip()
    if not q:
        return await get_timeline_events_for_user(db, user_id=user_id, limit=limit)
    pat = f"%{q}%"
    stmt = (
        select(TimelineEvent)
        .where(
            TimelineEvent.user_id == user_id,
            or_(
                TimelineEvent.title.ilike(pat),
                TimelineEvent.description.ilike(pat),
            ),
        )
        .order_by(TimelineEvent.event_year.desc().nullslast())
        .limit(limit)
    )
    result = await db.execute(stmt)
    rows = list(result.unique().scalars().all())
    if rows:
        return rows
    return await get_timeline_events_for_user(db, user_id=user_id, limit=limit)


async def search_chunks_vector(
    db: AsyncSession, user_id: str, query_embedding: list[float], limit: int = 20
) -> list[dict]:
    """Vector similarity search. Returns list of {id, content, chunk_index, distance}."""
    if not query_embedding:
        return []
    # pgvector cosine distance: 1 - cosine_similarity, lower is better
    stmt = text("""
        SELECT id, content, chunk_index,
               (embedding <=> CAST(:emb AS vector)) AS distance
        FROM memory_chunks
        WHERE user_id = :user_id AND (is_excluded IS NOT TRUE OR is_excluded = false)
          AND embedding IS NOT NULL
        ORDER BY embedding <=> CAST(:emb2 AS vector)
        LIMIT :lim
    """)
    emb_str = "[" + ",".join(str(x) for x in query_embedding) + "]"
    result = await db.execute(
        stmt,
        {"user_id": user_id, "emb": emb_str, "emb2": emb_str, "lim": limit},
    )
    rows = result.mappings().all()
    return [
        {
            "id": r["id"],
            "content": r["content"],
            "chunk_index": r["chunk_index"],
            "distance": float(r["distance"]),
        }
        for r in rows
    ]


def search_chunks_vector_sync(
    session: Session, user_id: str, query_embedding: list[float], limit: int = 20
) -> list[dict]:
    """pgvector 余弦距离检索（sync，Celery）。返回 {id, content, chunk_index, distance}。"""
    if not query_embedding:
        return []
    stmt = text("""
        SELECT id, content, chunk_index,
               (embedding <=> CAST(:emb AS vector)) AS distance
        FROM memory_chunks
        WHERE user_id = :user_id AND (is_excluded IS NOT TRUE OR is_excluded = false)
          AND embedding IS NOT NULL
        ORDER BY embedding <=> CAST(:emb2 AS vector)
        LIMIT :lim
    """)
    emb_str = "[" + ",".join(str(x) for x in query_embedding) + "]"
    result = session.execute(
        stmt,
        {"user_id": user_id, "emb": emb_str, "emb2": emb_str, "lim": limit},
    )
    rows = result.mappings().all()
    return [
        {
            "id": r["id"],
            "content": r["content"],
            "chunk_index": r["chunk_index"],
            "distance": float(r["distance"]),
        }
        for r in rows
    ]


def list_users_with_recent_chunks_sync(session: Session, *, hours: int) -> list[str]:
    """最近 N 小时内有新 chunk 的用户 id（Beat compaction 扫描）。"""
    if hours < 1:
        hours = 1
    cutoff = datetime.now(timezone.utc) - timedelta(hours=hours)
    stmt = (
        select(MemoryChunk.user_id).where(MemoryChunk.created_at >= cutoff).distinct()
    )
    return list(session.execute(stmt).scalars().all())


def list_summaries_for_evidence_sync(
    session: Session, *, user_id: str, q: str, limit: int
) -> list[dict]:
    """最新 rolling + 内容匹配 query 的摘要（ILIKE）。"""
    pat = f"%{q}%"
    rolling = (
        session.execute(
            select(MemorySummary)
            .where(
                MemorySummary.user_id == user_id,
                MemorySummary.summary_type == "rolling",
            )
            .order_by(MemorySummary.updated_at.desc())
            .limit(1)
        )
        .unique()
        .scalar_one_or_none()
    )
    rows: list[MemorySummary] = []
    seen: set[str] = set()
    if rolling:
        rows.append(rolling)
        seen.add(rolling.id)
    rest = limit - len(rows)
    if rest > 0:
        stmt = (
            select(MemorySummary)
            .where(
                MemorySummary.user_id == user_id,
                MemorySummary.content.ilike(pat),
            )
            .order_by(MemorySummary.updated_at.desc())
            .limit(rest + len(seen))
        )
        for s in session.execute(stmt).unique().scalars().all():
            if s.id not in seen:
                rows.append(s)
                seen.add(s.id)
            if len(rows) >= limit:
                break
    return [
        {
            "id": s.id,
            "summary_type": s.summary_type,
            "content": s.content,
            "source_chunk_ids": s.source_chunk_ids,
        }
        for s in rows[:limit]
    ]


def retrieve_evidence_sync(
    session: Session,
    user_id: str,
    query: str,
    *,
    top_k: int = 10,
    embedding_provider: "EmbeddingProvider | None" = None,
) -> dict:
    """
    Sync evidence retrieval for Celery tasks.

    chunks：**向量**（pgvector）与异步 `HybridRetriever` 对齐；facts/timeline 按 query ILIKE。
    """
    from app.features.memory.evidence import retrieve_evidence_bundle_sync

    return retrieve_evidence_bundle_sync(
        session,
        user_id,
        query,
        top_k=top_k,
        embedding_provider=embedding_provider,
    )


async def get_timeline_events_for_user(
    db: AsyncSession, user_id: str, limit: int = 20
) -> list[TimelineEvent]:
    """Fetch timeline events for user."""
    stmt = (
        select(TimelineEvent)
        .where(TimelineEvent.user_id == user_id)
        .order_by(
            TimelineEvent.event_year.desc().nullslast(), TimelineEvent.created_at.desc()
        )
        .limit(limit)
    )
    result = await db.execute(stmt)
    return list(result.unique().scalars().all())


async def list_storage_keys_for_conversation(
    db: AsyncSession, conversation_id: str
) -> list[str]:
    """对话关联的 memory_sources 上记录的 COS object key（若有）。"""
    stmt = select(MemorySource.storage_key).where(
        MemorySource.conversation_id == conversation_id,
        MemorySource.storage_key.isnot(None),
    )
    result = await db.execute(stmt)
    return sorted({r for r in result.scalars().all() if r})


def list_chunks_for_source_sync(session: Session, source_id: str) -> list[MemoryChunk]:
    stmt = (
        select(MemoryChunk)
        .where(MemoryChunk.source_id == source_id)
        .order_by(MemoryChunk.chunk_index.asc())
    )
    return list(session.execute(stmt).unique().scalars().all())


def create_memory_summary_sync(
    session: Session,
    *,
    user_id: str,
    summary_type: str,
    content: str,
    source_chunk_ids: list[str] | None = None,
) -> MemorySummary:
    row = MemorySummary(
        id=_new_id(),
        user_id=user_id,
        summary_type=summary_type,
        content=content,
        source_chunk_ids=source_chunk_ids,
    )
    session.add(row)
    return row


async def create_memory_summary(
    db: AsyncSession,
    *,
    user_id: str,
    summary_type: str,
    content: str,
    source_chunk_ids: list[str] | None = None,
) -> MemorySummary:
    row = MemorySummary(
        id=_new_id(),
        user_id=user_id,
        summary_type=summary_type,
        content=content,
        source_chunk_ids=source_chunk_ids,
    )
    db.add(row)
    return row


def get_latest_rolling_summary_sync(
    session: Session, user_id: str
) -> MemorySummary | None:
    stmt = (
        select(MemorySummary)
        .where(
            MemorySummary.user_id == user_id,
            MemorySummary.summary_type == "rolling",
        )
        .order_by(MemorySummary.updated_at.desc())
        .limit(1)
    )
    return session.execute(stmt).unique().scalar_one_or_none()


def upsert_rolling_summary_sync(
    session: Session,
    *,
    user_id: str,
    content: str,
    source_chunk_ids: list[str] | None = None,
) -> MemorySummary:
    existing = get_latest_rolling_summary_sync(session, user_id)
    if existing:
        existing.content = content
        if source_chunk_ids is not None:
            existing.source_chunk_ids = source_chunk_ids
        return existing
    return create_memory_summary_sync(
        session,
        user_id=user_id,
        summary_type="rolling",
        content=content,
        source_chunk_ids=source_chunk_ids,
    )


def create_memory_fact_sync(
    session: Session,
    *,
    user_id: str,
    fact_type: str,
    subject: str | None,
    predicate: str | None,
    object_json: dict | None,
    confidence: float,
    source_chunk_id: str | None,
    status: str = "confirmed",
) -> MemoryFact:
    row = MemoryFact(
        id=_new_id(),
        user_id=user_id,
        fact_type=fact_type,
        subject=subject,
        predicate=predicate,
        object_json=object_json,
        confidence=confidence,
        source_chunk_id=source_chunk_id,
        status=status,
    )
    session.add(row)
    return row


async def create_memory_fact(
    db: AsyncSession,
    *,
    user_id: str,
    fact_type: str,
    subject: str | None,
    predicate: str | None,
    object_json: dict | None,
    confidence: float,
    source_chunk_id: str | None,
    status: str = "confirmed",
) -> MemoryFact:
    row = MemoryFact(
        id=_new_id(),
        user_id=user_id,
        fact_type=fact_type,
        subject=subject,
        predicate=predicate,
        object_json=object_json,
        confidence=confidence,
        source_chunk_id=source_chunk_id,
        status=status,
    )
    db.add(row)
    return row


async def get_memory_fact_for_user(
    db: AsyncSession, fact_id: str, user_id: str
) -> MemoryFact | None:
    row = await db.get(MemoryFact, fact_id)
    if row is None or row.user_id != user_id:
        return None
    return row


async def set_memory_fact_status(
    db: AsyncSession, fact_id: str, user_id: str, status: str
) -> bool:
    row = await get_memory_fact_for_user(db, fact_id, user_id)
    if row is None:
        return False
    row.status = status
    return True


def delete_timeline_events_by_memory_source_sync(
    session: Session, *, user_id: str, memory_source_id: str
) -> int:
    stmt = delete(TimelineEvent).where(
        TimelineEvent.user_id == user_id,
        TimelineEvent.memory_source_id == memory_source_id,
    )
    result = session.execute(stmt)
    return result.rowcount or 0


async def delete_timeline_events_by_memory_source(
    db: AsyncSession, *, user_id: str, memory_source_id: str
) -> int:
    stmt = delete(TimelineEvent).where(
        TimelineEvent.user_id == user_id,
        TimelineEvent.memory_source_id == memory_source_id,
    )
    result = await db.execute(stmt)
    return result.rowcount or 0


def create_timeline_event_sync(
    session: Session,
    *,
    user_id: str,
    event_year: int | None,
    event_date: str | None,
    title: str,
    description: str | None,
    person_refs: list | None = None,
    source_fact_ids: list[str] | None = None,
    memory_source_id: str | None = None,
) -> TimelineEvent:
    row = TimelineEvent(
        id=_new_id(),
        user_id=user_id,
        memory_source_id=memory_source_id,
        event_year=event_year,
        event_date=event_date,
        title=title,
        description=description,
        person_refs=person_refs,
        source_fact_ids=source_fact_ids,
    )
    session.add(row)
    return row


async def create_timeline_event(
    db: AsyncSession,
    *,
    user_id: str,
    event_year: int | None,
    event_date: str | None,
    title: str,
    description: str | None,
    person_refs: list | None = None,
    source_fact_ids: list[str] | None = None,
    memory_source_id: str | None = None,
) -> TimelineEvent:
    row = TimelineEvent(
        id=_new_id(),
        user_id=user_id,
        memory_source_id=memory_source_id,
        event_year=event_year,
        event_date=event_date,
        title=title,
        description=description,
        person_refs=person_refs,
        source_fact_ids=source_fact_ids,
    )
    db.add(row)
    return row


def create_curation_action_sync(
    session: Session,
    *,
    user_id: str,
    action_type: str,
    target_type: str,
    target_id: str,
    details: dict | None = None,
) -> MemoryCurationAction:
    row = MemoryCurationAction(
        id=_new_id(),
        user_id=user_id,
        action_type=action_type,
        target_type=target_type,
        target_id=target_id,
        details=details,
    )
    session.add(row)
    return row


async def create_curation_action(
    db: AsyncSession,
    *,
    user_id: str,
    action_type: str,
    target_type: str,
    target_id: str,
    details: dict | None = None,
) -> MemoryCurationAction:
    row = MemoryCurationAction(
        id=_new_id(),
        user_id=user_id,
        action_type=action_type,
        target_type=target_type,
        target_id=target_id,
        details=details,
    )
    db.add(row)
    return row


async def get_memory_chunk_for_user(
    db: AsyncSession, chunk_id: str, user_id: str
) -> MemoryChunk | None:
    row = await db.get(MemoryChunk, chunk_id)
    if row is None or row.user_id != user_id:
        return None
    return row


def get_memory_chunk_sync(
    session: Session, chunk_id: str, user_id: str
) -> MemoryChunk | None:
    row = session.get(MemoryChunk, chunk_id)
    if row is None or row.user_id != user_id:
        return None
    return row


def set_chunk_excluded_sync(
    session: Session, chunk_id: str, user_id: str, excluded: bool
) -> bool:
    row = get_memory_chunk_sync(session, chunk_id, user_id)
    if row is None:
        return False
    row.is_excluded = excluded
    return True


def list_incremental_chunks_for_compaction_sync(
    session: Session,
    *,
    user_id: str,
    after_cursor_ts: datetime,
    after_chunk_id: str,
    limit: int,
    candidate_chunk_ids: list[str] | None = None,
    candidate_source_ids: list[str] | None = None,
) -> list[MemoryChunk]:
    """增量 chunk：(created_at, id) 字典序大于游标；可选与候选 id/source 求交。"""
    stmt = (
        select(MemoryChunk)
        .where(
            MemoryChunk.user_id == user_id,
            tuple_(MemoryChunk.created_at, MemoryChunk.id)
            > tuple_(literal(after_cursor_ts), literal(after_chunk_id)),
            or_(MemoryChunk.is_excluded.is_(False), MemoryChunk.is_excluded.is_(None)),
        )
        .order_by(MemoryChunk.created_at.asc(), MemoryChunk.id.asc())
        .limit(limit)
    )
    if candidate_chunk_ids:
        stmt = stmt.where(MemoryChunk.id.in_(candidate_chunk_ids))
    if candidate_source_ids:
        stmt = stmt.where(MemoryChunk.source_id.in_(candidate_source_ids))
    rows = session.execute(stmt).unique().scalars().all()
    return list(rows)


def get_first_chunk_after_cursor_sync(
    session: Session,
    *,
    user_id: str,
    after_cursor_ts: datetime,
    after_chunk_id: str,
) -> MemoryChunk | None:
    """游标之后字典序第一条 chunk（含 excluded），用于空增量时推进游标。"""
    stmt = (
        select(MemoryChunk)
        .where(
            MemoryChunk.user_id == user_id,
            tuple_(MemoryChunk.created_at, MemoryChunk.id)
            > tuple_(literal(after_cursor_ts), literal(after_chunk_id)),
        )
        .order_by(MemoryChunk.created_at.asc(), MemoryChunk.id.asc())
        .limit(1)
    )
    return session.execute(stmt).scalars().first()


def search_nearest_chunks_for_compaction_sync(
    session: Session,
    *,
    user_id: str,
    chunk_id: str,
    query_embedding: list[float],
    limit: int,
) -> list[dict]:
    """
    按余弦距离取 Top-K 近邻（不含自身）。pgvector `<=>` 为 cosine distance。
    返回 dict: id, content, source_id, event_year, metadata_json, source_type,
    distance, created_at
    """
    if not query_embedding:
        return []
    stmt = text("""
        SELECT mc.id, mc.content, mc.source_id, mc.event_year, mc.metadata_json,
               ms.source_type, mc.created_at,
               (mc.embedding <=> CAST(:emb AS vector)) AS distance
        FROM memory_chunks mc
        JOIN memory_sources ms ON ms.id = mc.source_id
        WHERE mc.user_id = :user_id
          AND (mc.is_excluded IS NOT TRUE OR mc.is_excluded = false)
          AND mc.embedding IS NOT NULL
          AND mc.id != :chunk_id
        ORDER BY mc.embedding <=> CAST(:emb2 AS vector)
        LIMIT :lim
    """)
    emb_str = "[" + ",".join(str(x) for x in query_embedding) + "]"
    result = session.execute(
        stmt,
        {
            "user_id": user_id,
            "chunk_id": chunk_id,
            "emb": emb_str,
            "emb2": emb_str,
            "lim": limit,
        },
    )
    return [
        {
            "id": r["id"],
            "content": r["content"],
            "source_id": r["source_id"],
            "event_year": r["event_year"],
            "metadata_json": r["metadata_json"],
            "source_type": r["source_type"],
            "created_at": r["created_at"],
            "distance": float(r["distance"]),
        }
        for r in result.mappings().all()
    ]


async def set_chunk_excluded(
    db: AsyncSession, chunk_id: str, user_id: str, excluded: bool
) -> bool:
    row = await get_memory_chunk_for_user(db, chunk_id, user_id)
    if row is None:
        return False
    row.is_excluded = excluded
    return True


async def list_summaries_for_evidence_async(
    db: AsyncSession, *, user_id: str, q: str, limit: int
) -> list[dict]:
    if not (q or "").strip():
        return []
    pat = f"%{q.strip()}%"
    rolling_stmt = (
        select(MemorySummary)
        .where(
            MemorySummary.user_id == user_id,
            MemorySummary.summary_type == "rolling",
        )
        .order_by(MemorySummary.updated_at.desc())
        .limit(1)
    )
    r_result = await db.execute(rolling_stmt)
    rolling = r_result.unique().scalar_one_or_none()
    rows: list[MemorySummary] = []
    seen: set[str] = set()
    if rolling:
        rows.append(rolling)
        seen.add(rolling.id)
    rest = limit - len(rows)
    if rest > 0:
        stmt = (
            select(MemorySummary)
            .where(
                MemorySummary.user_id == user_id,
                MemorySummary.content.ilike(pat),
            )
            .order_by(MemorySummary.updated_at.desc())
            .limit(rest + len(seen))
        )
        o_result = await db.execute(stmt)
        for s in o_result.unique().scalars().all():
            if s.id not in seen:
                rows.append(s)
                seen.add(s.id)
            if len(rows) >= limit:
                break
    return [
        {
            "id": s.id,
            "summary_type": s.summary_type,
            "content": s.content,
            "source_chunk_ids": s.source_chunk_ids,
        }
        for s in rows[:limit]
    ]