# src/api/routes/knowledge.py
"""知识库检索接口"""

from fastapi import APIRouter, HTTPException
from loguru import logger

from ..models import SearchRequest, SearchResponse, SearchResultItem, ErrorResponse
from app.services.document_processor import DocumentProcessor

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


@router.post("/search", response_model=SearchResponse)
async def search_knowledge(request: SearchRequest):
    """
    检索法规知识库

    使用混合检索：Dense向量 + Sparse向量 + RRF融合

    Args:
        request: 检索请求参数
    """
    if not request.query or len(request.query.strip()) == 0:
        raise HTTPException(
            status_code=400,
            detail="查询文本不能为空"
        )

    logger.info(f"收到检索请求: {request.query}")

    try:
        # 执行检索
        processor = DocumentProcessor()
        results = processor.search(
            query=request.query,
            top_k=request.top_k,
            filters=request.filters
        )
        processor.close()

        # 转换结果格式
        result_items = []
        for r in results:
            item = SearchResultItem(
                id=r.get("id", 0),
                content=r.get("content", ""),
                score=r.get("score", 0.0),
                metadata=r.get("metadata", {})
            )
            result_items.append(item)

        return SearchResponse(
            query=request.query,
            total=len(result_items),
            results=result_items
        )

    except Exception as e:
        logger.error(f"检索失败: {e}")
        raise HTTPException(
            status_code=500,
            detail=f"检索失败: {str(e)}"
        )


@router.post("/retrieval", response_model=SearchResponse)
async def knowledge_retrieval(request: SearchRequest):
    """
    知识检索接口（与架构文档对齐）

    该接口实现完整的检索流程：
    1. 意图识别
    2. BM25关键词检索 + 向量语义检索（双路召回）
    3. Cross-Encoder精排
    4. 返回结果

    Args:
        request: 检索请求
    """
    # 当前版本使用混合检索，后续可添加精排步骤
    return await search_knowledge(request)