from fastapi import APIRouter, Depends, HTTPException, Query
from pydantic import BaseModel
from typing import Optional
import aiosqlite
from database import get_db

router = APIRouter(prefix="/api/knowledge", tags=["knowledge"])

class KnowledgePatch(BaseModel):
    content: str

@router.get("")
async def list_knowledge(
    keyword: Optional[str] = None,
    db: aiosqlite.Connection = Depends(get_db)
):
    if keyword:
        # FTS5 查询前先用 jieba 分词，提高中文召回率
        from services.fts import build_match_query
        fts_query = build_match_query(keyword)
        if not fts_query:
            return []
        async with db.execute(
            "SELECT k.id, k.topic_id, k.created_at, k.updated_at, t.title, t.group_id, g.name as group_name "
            "FROM knowledge_docs k JOIN topics t ON k.topic_id=t.id "
            "LEFT JOIN groups g ON t.group_id=g.id "
            "WHERE k.id IN (SELECT doc_id FROM knowledge_fts WHERE knowledge_fts MATCH ?)",
            (fts_query,)
        ) as cur:
            return [dict(r) for r in await cur.fetchall()]
    async with db.execute(
        "SELECT k.id, k.topic_id, k.created_at, k.updated_at, t.title, t.group_id, g.name as group_name "
        "FROM knowledge_docs k JOIN topics t ON k.topic_id=t.id "
        "LEFT JOIN groups g ON t.group_id=g.id "
        "ORDER BY g.name, k.updated_at DESC"
    ) as cur:
        return [dict(r) for r in await cur.fetchall()]

@router.get("/{doc_id}")
async def get_knowledge(doc_id: int, db: aiosqlite.Connection = Depends(get_db)):
    async with db.execute("SELECT * FROM knowledge_docs WHERE id=?", (doc_id,)) as cur:
        row = await cur.fetchone()
    if not row:
        raise HTTPException(404, "not found")
    return dict(row)

@router.patch("/{doc_id}")
async def patch_knowledge(doc_id: int, body: KnowledgePatch, db: aiosqlite.Connection = Depends(get_db)):
    await db.execute(
        "UPDATE knowledge_docs SET content=?, updated_at=CURRENT_TIMESTAMP, curated_at=CURRENT_TIMESTAMP WHERE id=?",
        (body.content, doc_id)
    )
    await db.commit()
    # update FTS
    async with db.execute("SELECT topic_id FROM knowledge_docs WHERE id=?", (doc_id,)) as cur:
        row = await cur.fetchone()
    if row:
        async with db.execute("SELECT title FROM topics WHERE id=?", (row["topic_id"],)) as cur:
            topic = await cur.fetchone()
        await db.execute("DELETE FROM knowledge_fts WHERE doc_id=?", (doc_id,))
        from services.fts import tokenize
        await db.execute(
            "INSERT INTO knowledge_fts (doc_id, title, content) VALUES (?, ?, ?)",
            (doc_id, tokenize(topic["title"]), tokenize(body.content))
        )
        await db.commit()
    return {"ok": True}