import math
from typing import Literal, Optional

from fastapi import APIRouter, Depends, Query
from sqlalchemy.ext.asyncio import AsyncSession

from app.api.v1 import ok
from app.core.dependencies import get_db
from app.schemas.document import (
    CreateDocumentRequest,
    DocumentListItem,
    DocumentResponse,
    Pagination,
    UpdateDocumentRequest,
)
from app.services.document_service import DocumentService

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


@router.post("", summary="创建文档（下载 Word 转 Markdown）")
async def create_document(
    body: CreateDocumentRequest,
    db: AsyncSession = Depends(get_db),
) -> dict:
    svc = DocumentService(db)
    doc = await svc.create_document(body)
    return ok({
        "documentId": doc.id,
        "format": doc.format,
        "createdAt": int(doc.created_at.timestamp() * 1000),
    })


@router.get("", summary="获取文档列表")
async def list_documents(
    userId: str = Query(...),
    page: int = Query(1, ge=1),
    pageSize: int = Query(20, ge=1, le=100),
    sessionId: Optional[str] = Query(None),
    sortBy: Literal["created_at", "updated_at"] = Query("updated_at"),
    sortOrder: Literal["asc", "desc"] = Query("desc"),
    db: AsyncSession = Depends(get_db),
) -> dict:
    svc = DocumentService(db)
    docs, total = await svc.list_documents(
        user_id=userId,
        page=page,
        page_size=pageSize,
        session_id=sessionId,
        sort_by=sortBy,
        sort_order=sortOrder,
    )
    items = [DocumentListItem.model_validate(d).model_dump(by_alias=True) for d in docs]
    pagination = Pagination(
        page=page,
        page_size=pageSize,
        total=total,
        total_pages=math.ceil(total / pageSize) if pageSize else 1,
    ).model_dump(by_alias=True)
    return ok({"documents": items, "pagination": pagination})


@router.get("/{documentId}", summary="获取文档详情")
async def get_document(
    documentId: str,
    db: AsyncSession = Depends(get_db),
) -> dict:
    svc = DocumentService(db)
    doc = await svc.get_document(documentId)
    data = DocumentResponse.model_validate(doc).model_dump(by_alias=True)
    # 将 created_by 映射为 userId
    data["userId"] = data.pop("user_id", None)
    return ok(data)


@router.put("/{documentId}", summary="更新文档")
async def update_document(
    documentId: str,
    body: UpdateDocumentRequest,
    db: AsyncSession = Depends(get_db),
) -> dict:
    svc = DocumentService(db)
    doc = await svc.update_document(documentId, body)
    return ok({
        "documentId": doc.id,
        "updatedAt": int(doc.updated_at.timestamp() * 1000),
    })


@router.delete("/{sessionId}", summary="删除会话的所有文档")
async def delete_documents_by_session(
    sessionId: str,
    db: AsyncSession = Depends(get_db),
) -> dict:
    svc = DocumentService(db)
    deleted_count = await svc.delete_documents_by_session(sessionId)
    return {"code": 0, "message": f"Deleted {deleted_count} document(s) successfully"}