hyungi_document_server/app/api/memos.py

"""메모 CRUD API — 파일 없는 문서(file_type='note')"""

import hashlib
import logging
import re
from datetime import datetime, timezone
from typing import Annotated

from fastapi import APIRouter, Depends, HTTPException, Query
from pydantic import BaseModel
from sqlalchemy import delete, func, select
from sqlalchemy.ext.asyncio import AsyncSession

from core.auth import get_current_user
from core.database import get_session
from models.document import Document
from models.queue import ProcessingQueue, enqueue_stage
from models.user import User

logger = logging.getLogger(__name__)

router = APIRouter()

# markdown task line: "- [ ] ..." 또는 "- [x] ..."
TASK_LINE_RE = re.compile(r"^(\s*- \[)([ xX])(\].*)$")

# #태그 파싱 패턴: 한글/영문/숫자/밑줄, 2자 이상
TAG_PATTERN = re.compile(r"(?:^|(?<=\s))#([가-힣a-zA-Z0-9_]{2,})")


def _parse_hashtags(content: str) -> list[str]:
    """본문에서 #태그 추출, 중복 제거, 순서 유지"""
    seen: set[str] = set()
    tags: list[str] = []
    for m in TAG_PATTERN.finditer(content):
        tag = m.group(1)
        if tag not in seen:
            seen.add(tag)
            tags.append(tag)
    return tags


def _content_hash(content: str) -> str:
    """메모 본문의 SHA-256 해시 (note의 file_hash = content hash)"""
    return hashlib.sha256(content.encode("utf-8")).hexdigest()


def _auto_title(content: str) -> str:
    """첫 줄에서 제목 자동 생성 (80자 절단, 마크다운 헤딩 제거)"""
    first_line = content.split("\n", 1)[0].strip()
    title = re.sub(r"^#+\s*", "", first_line)[:80] or "메모"
    return title


def _toggle_task_line(content: str, target_index: int, checked: bool) -> tuple[str, bool]:
    """N번째 markdown task line을 찾아 checked/unchecked 상태로 설정.

    (new_content, found) 반환. found=False면 target_index에 해당하는 task line이 없음
    (본문 편집으로 drift된 경우).
    """
    lines = content.split("\n")
    ti = 0
    found = False
    for i, line in enumerate(lines):
        m = TASK_LINE_RE.match(line)
        if not m:
            continue
        if ti == target_index:
            mark = "x" if checked else " "
            lines[i] = m.group(1) + mark + m.group(3)
            found = True
            break
        ti += 1
    return "\n".join(lines), found


async def _enqueue_ai_stages(session: AsyncSession, document_id: int):
    """classify + embed + chunk 큐 등록. 기존 pending 건 정리 (중복 방지)."""
    stages = ["classify", "embed", "chunk"]
    await session.execute(
        delete(ProcessingQueue).where(
            ProcessingQueue.document_id == document_id,
            ProcessingQueue.stage.in_(stages),
            ProcessingQueue.status == "pending",
        )
    )
    for stage in stages:
        await enqueue_stage(session, document_id, stage)


# ─── 스키마 ───


class MemoCreate(BaseModel):
    content: str
    title: str | None = None  # 선택적 제목 (없으면 첫 줄 자동 생성)
    ask_includable: bool = True


class MemoUpdate(BaseModel):
    content: str
    title: str | None = None  # 명시 제목 변경 (None이면 자동 생성)


class ArchiveSet(BaseModel):
    archived: bool


class TaskToggle(BaseModel):
    checked: bool


class MemoResponse(BaseModel):
    id: int
    title: str | None
    content: str | None  # extracted_text
    file_format: str
    user_tags: list | None
    ai_tags: list | None
    ai_domain: str | None
    ai_sub_group: str | None
    ai_summary: str | None
    pinned: bool
    archived: bool
    ask_includable: bool
    memo_task_state: dict  # {"<task_index>": {"checked_at": "<ISO8601>"}}
    created_at: datetime
    updated_at: datetime

    class Config:
        from_attributes = True


class MemoListResponse(BaseModel):
    items: list[MemoResponse]
    total: int
    page: int
    page_size: int


def _to_memo_response(doc: Document) -> MemoResponse:
    return MemoResponse(
        id=doc.id,
        title=doc.title,
        content=doc.extracted_text,
        file_format=doc.file_format,
        user_tags=doc.user_tags,
        ai_tags=doc.ai_tags,
        ai_domain=doc.ai_domain,
        ai_sub_group=doc.ai_sub_group,
        ai_summary=doc.ai_summary,
        pinned=doc.pinned,
        archived=doc.archived,
        ask_includable=doc.ask_includable,
        memo_task_state=dict(doc.memo_task_state or {}),
        created_at=doc.created_at,
        updated_at=doc.updated_at,
    )


# ─── 엔드포인트 ───


@router.post("/", response_model=MemoResponse, status_code=201)
async def create_memo(
    body: MemoCreate,
    user: Annotated[User, Depends(get_current_user)],
    session: Annotated[AsyncSession, Depends(get_session)],
):
    """메모 생성 — file_type='note', 파일 없는 문서"""
    content = body.content.strip()
    if not content:
        raise HTTPException(status_code=400, detail="메모 내용이 비어있습니다")

    doc = Document(
        file_path=None,
        file_hash=_content_hash(content),
        file_format="md",
        file_size=len(content.encode("utf-8")),
        file_type="note",
        title=body.title.strip() if body.title and body.title.strip() else _auto_title(content),
        extracted_text=content,
        review_status="approved",
        source_channel="memo",
        user_tags=_parse_hashtags(content),
        pinned=False,
        archived=False,
        ask_includable=body.ask_includable,
    )
    session.add(doc)
    await session.flush()

    await _enqueue_ai_stages(session, doc.id)
    await session.commit()
    await session.refresh(doc)

    return _to_memo_response(doc)


@router.get("/", response_model=MemoListResponse)
async def list_memos(
    user: Annotated[User, Depends(get_current_user)],
    session: Annotated[AsyncSession, Depends(get_session)],
    page: int = Query(1, ge=1),
    page_size: int = Query(20, ge=1, le=100),
    tag: str | None = Query(None, description="user_tags 또는 ai_tags 필터"),
    archived: bool = Query(False, description="true면 아카이브 목록"),
    pinned: bool | None = Query(None, description="true면 핀 고정된 메모만"),
):
    """메모 목록 — 활성: 핀 우선 + 최신순 / 아카이브: 최신순 (핀 무시)"""
    base = select(Document).where(
        Document.file_type == "note",
        Document.source_channel == "memo",
        Document.deleted_at == None,  # noqa: E711
        Document.archived == archived,
    )

    if pinned is not None:
        base = base.where(Document.pinned == pinned)

    if tag:
        base = base.where(
            Document.user_tags.op("@>")(f'["{tag}"]')
            | Document.ai_tags.op("@>")(f'["{tag}"]')
        )

    count_query = select(func.count()).select_from(base.subquery())
    total = (await session.execute(count_query)).scalar() or 0

    # 활성: pinned DESC + created_at DESC / 아카이브: created_at DESC (핀 무시)
    if archived:
        query = base.order_by(Document.created_at.desc())
    else:
        query = base.order_by(Document.pinned.desc(), Document.created_at.desc())

    query = query.offset((page - 1) * page_size).limit(page_size)
    result = await session.execute(query)
    items = result.scalars().all()

    return MemoListResponse(
        items=[_to_memo_response(doc) for doc in items],
        total=total,
        page=page,
        page_size=page_size,
    )


@router.get("/{memo_id}", response_model=MemoResponse)
async def get_memo(
    memo_id: int,
    user: Annotated[User, Depends(get_current_user)],
    session: Annotated[AsyncSession, Depends(get_session)],
):
    """메모 단건 조회"""
    doc = await session.get(Document, memo_id)
    if not doc or doc.file_type != "note" or doc.deleted_at is not None:
        raise HTTPException(status_code=404, detail="메모를 찾을 수 없습니다")
    return _to_memo_response(doc)


@router.patch("/{memo_id}", response_model=MemoResponse)
async def update_memo(
    memo_id: int,
    body: MemoUpdate,
    user: Annotated[User, Depends(get_current_user)],
    session: Annotated[AsyncSession, Depends(get_session)],
):
    """메모 수정 — content 변경 시 AI 데이터 초기화 + 재처리 큐 등록"""
    doc = await session.get(Document, memo_id)
    if not doc or doc.file_type != "note" or doc.deleted_at is not None:
        raise HTTPException(status_code=404, detail="메모를 찾을 수 없습니다")

    content = body.content.strip()
    if not content:
        raise HTTPException(status_code=400, detail="메모 내용이 비어있습니다")

    doc.extracted_text = content
    doc.file_hash = _content_hash(content)
    doc.file_size = len(content.encode("utf-8"))
    # PATCH semantics: title 필드를 명시적으로 보낸 경우만 덮어쓴다.
    # 체크박스 토글 경로처럼 {content}만 PATCH 하면 기존 title을 보존해야 함
    # (이전엔 None→_auto_title(content)로 제목이 체크박스 라인으로 덮어씌워지는 버그).
    if "title" in body.model_fields_set:
        doc.title = body.title.strip() if body.title and body.title.strip() else _auto_title(content)
    elif not (doc.title or "").strip():
        # 기존 title이 비어 있던 경우만 보강
        doc.title = _auto_title(content)
    doc.user_tags = _parse_hashtags(content)

    # stale AI 데이터 즉시 초기화
    doc.ai_summary = None
    doc.ai_domain = None
    doc.ai_sub_group = None
    doc.ai_tags = None
    doc.ai_confidence = None
    doc.ai_processed_at = None
    doc.embedding = None
    doc.embedded_at = None

    # 기존 chunks 삭제
    from models.chunk import DocumentChunk
    await session.execute(
        delete(DocumentChunk).where(DocumentChunk.doc_id == memo_id)
    )

    # 재처리 큐 등록
    await _enqueue_ai_stages(session, memo_id)

    doc.updated_at = datetime.now(timezone.utc)
    await session.commit()
    await session.refresh(doc)

    return _to_memo_response(doc)


@router.patch("/{memo_id}/tasks/{task_index}", response_model=MemoResponse)
async def toggle_memo_task(
    memo_id: int,
    task_index: int,
    body: TaskToggle,
    user: Annotated[User, Depends(get_current_user)],
    session: Annotated[AsyncSession, Depends(get_session)],
):
    """메모 체크박스 토글 전용 엔드포인트.

    N번째 markdown task line의 체크 상태를 설정하고 memo_task_state에 시각 기록.
    AI 재처리(classify/embed/chunk)는 **의도적으로 스킵** — 체크박스 한 번에 재분석을 트리거하는 건 과하다.
    같은 row를 동시에 토글하는 race 방지를 위해 SELECT ... FOR UPDATE 사용.
    """
    # ❶ FOR UPDATE: 같은 row 동시 토글 race 차단 (JSONB 전체 replace라 필수)
    doc = await session.get(Document, memo_id, with_for_update=True)
    if not doc or doc.file_type != "note" or doc.deleted_at is not None:
        raise HTTPException(status_code=404, detail="메모를 찾을 수 없습니다")

    state = dict(doc.memo_task_state or {})
    key = str(task_index)

    # ❷ content의 N번째 task line 토글
    new_content, found = _toggle_task_line(doc.extracted_text or "", task_index, body.checked)
    if not found:
        # drift: 사용자가 본문 편집으로 task_index 매칭이 깨짐 → stale state만 정리하고 200 OK
        stale_removed = key in state
        if stale_removed:
            state.pop(key, None)
            doc.memo_task_state = state
            await session.commit()
            await session.refresh(doc)
        logger.info(
            "memo_task_toggle_drift memo_id=%s task_index=%s stale_removed=%s",
            memo_id, task_index, stale_removed,
        )
        return _to_memo_response(doc)

    doc.extracted_text = new_content
    doc.file_hash = _content_hash(new_content)
    doc.file_size = len(new_content.encode("utf-8"))

    # ❸ task_state 갱신 (JSONB 전체 replace — FOR UPDATE lock 아래라 race safe)
    if body.checked:
        state[key] = {"checked_at": datetime.now(timezone.utc).isoformat()}
    else:
        state.pop(key, None)
    doc.memo_task_state = state

    doc.updated_at = datetime.now(timezone.utc)
    # AI 재처리 / user_tags 재파싱 / chunks 삭제 / queue enqueue — 모두 의도적 스킵.
    # 왜 스킵하는지 나중에 디버깅하지 않아도 되도록 명시 로그.
    logger.info(
        "memo_task_toggle_skip_ai memo_id=%s task_index=%s checked=%s",
        memo_id, task_index, body.checked,
    )

    await session.commit()
    await session.refresh(doc)
    return _to_memo_response(doc)


@router.delete("/{memo_id}", status_code=204)
async def delete_memo(
    memo_id: int,
    user: Annotated[User, Depends(get_current_user)],
    session: Annotated[AsyncSession, Depends(get_session)],
):
    """메모 soft delete"""
    doc = await session.get(Document, memo_id)
    if not doc or doc.file_type != "note" or doc.deleted_at is not None:
        raise HTTPException(status_code=404, detail="메모를 찾을 수 없습니다")

    doc.deleted_at = datetime.now(timezone.utc)
    await session.commit()


@router.patch("/{memo_id}/pin", response_model=MemoResponse)
async def toggle_pin(
    memo_id: int,
    user: Annotated[User, Depends(get_current_user)],
    session: Annotated[AsyncSession, Depends(get_session)],
):
    """메모 핀 토글"""
    doc = await session.get(Document, memo_id)
    if not doc or doc.file_type != "note" or doc.deleted_at is not None:
        raise HTTPException(status_code=404, detail="메모를 찾을 수 없습니다")

    doc.pinned = not doc.pinned
    doc.updated_at = datetime.now(timezone.utc)
    await session.commit()
    await session.refresh(doc)

    return _to_memo_response(doc)


@router.patch("/{memo_id}/archive", response_model=MemoResponse)
async def set_archive(
    memo_id: int,
    body: ArchiveSet,
    user: Annotated[User, Depends(get_current_user)],
    session: Annotated[AsyncSession, Depends(get_session)],
):
    """메모 아카이브 설정 (멱등, 토글 아님)"""
    doc = await session.get(Document, memo_id)
    if not doc or doc.file_type != "note" or doc.deleted_at is not None:
        raise HTTPException(status_code=404, detail="메모를 찾을 수 없습니다")

    doc.archived = body.archived
    doc.updated_at = datetime.now(timezone.utc)
    await session.commit()
    await session.refresh(doc)

    return _to_memo_response(doc)


@router.patch("/{memo_id}/ask-includable", response_model=MemoResponse)
async def toggle_ask_includable(
    memo_id: int,
    user: Annotated[User, Depends(get_current_user)],
    session: Annotated[AsyncSession, Depends(get_session)],
):
    """/ask 합성 포함 여부 토글"""
    doc = await session.get(Document, memo_id)
    if not doc or doc.file_type != "note" or doc.deleted_at is not None:
        raise HTTPException(status_code=404, detail="메모를 찾을 수 없습니다")

    doc.ask_includable = not doc.ask_includable
    doc.updated_at = datetime.now(timezone.utc)
    await session.commit()
    await session.refresh(doc)

    return _to_memo_response(doc)