from fastapi import APIRouter, UploadFile, Form, HTTPException, Depends
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy.future import select
from app.database import get_db
from app.models import VideoUpload
from .utils.s3 import upload_to_s3, delete_s3_key, key_from_url
from app.auth import get_current_user
from app.models import User
from sqlalchemy import delete as sqldelete
import uuid
import os

router = APIRouter()

# Accept any video file
ALLOWED_VIDEO_MIME_TYPES = {
    "video/mp4",
    "video/x-matroska",  # mkv
    "video/quicktime",  # mov
    "video/x-msvideo",  # avi
    "video/webm",
    "video/mpeg",
}


@router.post("/upload")
async def upload_video(
    user_id: int = Form(...),
    file: UploadFile = Form(...),
    db: AsyncSession = Depends(get_db),
):
    if file.content_type not in ALLOWED_VIDEO_MIME_TYPES:
        raise HTTPException(
            status_code=400, detail=f"Unsupported file type: {file.content_type}"
        )

    try:
        uid = str(uuid.uuid4())
        s3_key = f"videos/{uid}/{file.filename}"
        video_url = upload_to_s3(file, s3_key)

        new_video = VideoUpload(
            user_id=user_id,
            video_url=video_url,
            pdf_url="",  # will be set after analysis
            status="pending",
        )
        db.add(new_video)
        await db.commit()
        await db.refresh(new_video)

        return {"status": "uploaded", "video_url": video_url, "video_id": new_video.id}

    except Exception as e:
        await db.rollback()
        raise HTTPException(status_code=500, detail=str(e))


@router.delete("/uploads/{video_id}")
async def delete_uploaded_video(video_id: int,
                                current_user: User = Depends(get_current_user),
                                db: AsyncSession = Depends(get_db)):
    result = await db.execute(select(VideoUpload).where(VideoUpload.id == video_id))
    video: VideoUpload | None = result.scalar_one_or_none()
    if not video:
        raise HTTPException(status_code=404, detail="Video not found")
    if video.user_id != current_user.id:
        raise HTTPException(status_code=403, detail="Not allowed")

    # Delete from S3 if present
    v_key = key_from_url(video.video_url)
    p_key = key_from_url(video.pdf_url)
    try:
        if v_key:
            delete_s3_key(v_key)
        if p_key:
            delete_s3_key(p_key)
    except Exception:
        pass

    # Delete DB row
    try:
        await db.delete(video)
        await db.commit()
        return {"message": "Upload deleted"}
    except Exception as e:
        await db.rollback()
        raise HTTPException(status_code=500, detail=str(e))


@router.delete("/uploads/{video_id}/pdf")
async def delete_uploaded_pdf(video_id: int,
                              current_user: User = Depends(get_current_user),
                              db: AsyncSession = Depends(get_db)):
    result = await db.execute(select(VideoUpload).where(VideoUpload.id == video_id))
    video: VideoUpload | None = result.scalar_one_or_none()
    if not video:
        raise HTTPException(status_code=404, detail="Upload not found")
    if video.user_id != current_user.id:
        raise HTTPException(status_code=403, detail="Not allowed")

    p_key = key_from_url(video.pdf_url)
    if not p_key:
        return {"message": "No PDF to delete"}
    try:
        delete_s3_key(p_key)
    except Exception:
        pass
    # Clear pdf_url field
    video.pdf_url = ""
    try:
        await db.commit()
        await db.refresh(video)
        return {"message": "PDF deleted", "video_id": video.id}
    except Exception as e:
        await db.rollback()
        raise HTTPException(status_code=500, detail=str(e))