from fastapi import APIRouter, Depends, File, Form, UploadFile
from sqlalchemy.orm import Session

from app.core.response import ApiResponse, ok
from app.core.user_context import UserContext, get_user_context
from app.db.session import get_db
from app.repositories.knowledge_base_repository import KnowledgeBaseRepository
from app.schemas.knowledge_admin import (
    KnowledgeDocumentDetailResponse,
    KnowledgeDocumentListResponse,
    KnowledgeDocumentUploadResponse,
)
from app.services.document_ingestion_service import DocumentIngestionService
from app.services.knowledge_space_service import KnowledgeSpaceService

router = APIRouter()


@router.post("/documents/upload", response_model=ApiResponse[KnowledgeDocumentUploadResponse])
async def upload_knowledge_document(
    file: UploadFile = File(..., description="PDF 文件"),
    document_title: str | None = Form(default=None, description="文档标题"),
    document_category: str = Form(default="textbook", description="文档分类：textbook/guideline/manual/other"),
    version: str = Form(default="v1", description="文档版本"),
    ctx: UserContext = Depends(get_user_context),
    db: Session = Depends(get_db),
):
    """知识库上传：内容管理员上传 PDF，并触发机构知识库构建。"""
    result = await DocumentIngestionService(db).upload_pdf(
        ctx,
        file,
        document_title=document_title,
        document_category=document_category,
        version=version,
    )
    db.commit()
    return ok(result)


@router.get("/documents", response_model=ApiResponse[KnowledgeDocumentListResponse])
def list_knowledge_documents(
    ctx: UserContext = Depends(get_user_context),
    db: Session = Depends(get_db),
):
    """知识库文档列表：内容管理员查看本机构已上传文档。"""
    repo = KnowledgeBaseRepository(db)
    KnowledgeSpaceService(repo).ensure_content_admin(ctx)
    institution_id = KnowledgeSpaceService(repo).require_institution_id(ctx)
    items = [_to_detail(item) for item in repo.list_documents(institution_id)]
    return ok(KnowledgeDocumentListResponse(items=items))


@router.get("/documents/{document_id}", response_model=ApiResponse[KnowledgeDocumentDetailResponse])
def get_knowledge_document(
    document_id: int,
    ctx: UserContext = Depends(get_user_context),
    db: Session = Depends(get_db),
):
    """知识库文档详情：按机构隔离返回 PDF 构建状态。"""
    repo = KnowledgeBaseRepository(db)
    KnowledgeSpaceService(repo).ensure_content_admin(ctx)
    institution_id = KnowledgeSpaceService(repo).require_institution_id(ctx)
    document = repo.get_document(document_id, institution_id)
    if not document:
        from app.core.exceptions import AppError

        raise AppError("KNOWLEDGE_DOCUMENT_NOT_FOUND", "knowledge document not found", 404)
    return ok(_to_detail(document))


def _to_detail(document) -> KnowledgeDocumentDetailResponse:
    """响应转换：把 ORM 文档对象转换为 API 文档详情。"""
    return KnowledgeDocumentDetailResponse(
        document_id=document.id,
        institution_id=document.institution_id,
        file_name=document.file_name,
        document_title=document.document_title,
        document_category=document.document_category,
        version=document.version,
        status=document.status,
        parse_status=document.parse_status,
        embedding_status=document.embedding_status,
        chunk_count=document.chunk_count,
        error_message=document.error_message,
        created_at=getattr(document, "created_at", None),
        updated_at=getattr(document, "updated_at", None),
    )