from __future__ import annotations

from fastapi import APIRouter, Depends, File, Form, HTTPException, UploadFile
from fastapi.responses import Response
from sqlalchemy.ext.asyncio import AsyncSession

from app.api.deps import get_current_user, get_db
from app.schemas import DocumentListResponse, DocumentResponse
from app.services.documents import create_document, get_document, list_documents
from app.services.storage import storage_client
from dlib.auth import AuthenticatedUser


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


@router.get("", response_model=DocumentListResponse)
async def list_user_documents(
    session: AsyncSession = Depends(get_db),
    user: AuthenticatedUser = Depends(get_current_user),
):
    documents = await list_documents(session, owner_id=user.sub)
    payload = [DocumentResponse.model_validate(doc) for doc in documents]
    return DocumentListResponse(items=payload)


@router.get("/{document_id}", response_model=DocumentResponse)
async def get_user_document(
    document_id: str,
    session: AsyncSession = Depends(get_db),
    user: AuthenticatedUser = Depends(get_current_user),
):
    document = await get_document(session, owner_id=user.sub, document_id=document_id)
    if not document:
        raise HTTPException(status_code=404, detail="Document not found")
    return DocumentResponse.model_validate(document)


@router.get("/{document_id}/versions/{version_id}/download")
async def download_version_docx(
    document_id: str,
    version_id: str,
    session: AsyncSession = Depends(get_db),
    user: AuthenticatedUser = Depends(get_current_user),
):
    document = await get_document(session, owner_id=user.sub, document_id=document_id)
    if not document:
        raise HTTPException(status_code=404, detail="Document not found")
    version = next((v for v in document.versions if v.id == version_id), None)
    if not version or not version.artifact_docx_key:
        raise HTTPException(status_code=404, detail="Version artifact not found")
    data = storage_client.download_bytes(key=version.artifact_docx_key)
    slug = f"{document.title.replace(' ', '-')}-{version.branch_name}.docx"
    return Response(
        content=data,
        media_type="application/vnd.openxmlformats-officedocument.wordprocessingml.document",
        headers={"Content-Disposition": f'attachment; filename="{slug}"'},
    )


@router.post("", response_model=DocumentResponse)
async def upload_document(
    title: str = Form(...),
    description: str | None = Form(default=None),
    file: UploadFile = File(...),
    session: AsyncSession = Depends(get_db),
    user: AuthenticatedUser = Depends(get_current_user),
):
    document = await create_document(
        session,
        owner_id=user.sub,
        title=title,
        description=description,
        upload=file,
    )
    return DocumentResponse.model_validate(document)