import asyncio
import uuid
from datetime import datetime, timezone
from pathlib import Path

from fastapi import APIRouter, HTTPException
from fastapi.responses import FileResponse

from config import FORMAT_META, STORAGE_DIR
from database import create_guide, delete_guide, get_guide, list_guides
from generator import generate_guide, cancel_guide
from models import GuideCreateRequest, GuideResponse

router = APIRouter(prefix="/api")


@router.get("/formats")
async def get_formats():
    return FORMAT_META


@router.post("/guides", response_model=GuideResponse)
async def create(req: GuideCreateRequest):
    now = datetime.now(timezone.utc).isoformat()
    guide = {
        "id": str(uuid.uuid4()),
        "topic": req.topic.strip(),
        "format": req.format,
        "status": "queued",
        "progress": None,
        "html_path": None,
        "pdf_path": None,
        "created_at": now,
        "updated_at": now,
    }
    await create_guide(guide)
    asyncio.create_task(generate_guide(guide["id"], guide["topic"], guide["format"]))
    return guide


@router.get("/guides", response_model=list[GuideResponse])
async def list_all():
    return await list_guides()


@router.get("/guides/{guide_id}", response_model=GuideResponse)
async def get_one(guide_id: str):
    guide = await get_guide(guide_id)
    if guide is None:
        raise HTTPException(404, "Guide nicht gefunden")
    return guide


@router.get("/guides/{guide_id}/html")
async def download_html(guide_id: str):
    guide = await get_guide(guide_id)
    if guide is None:
        raise HTTPException(404, "Guide nicht gefunden")
    if guide["status"] != "done" or not guide["html_path"]:
        raise HTTPException(404, "HTML nicht verfügbar")
    path = Path(guide["html_path"])
    if not path.exists():
        raise HTTPException(404, "Datei nicht gefunden")
    return FileResponse(path, filename=f"{guide['topic']}-{guide['format']}.html", media_type="text/html")


@router.post("/guides/{guide_id}/cancel")
async def cancel(guide_id: str):
    cancelled = await cancel_guide(guide_id)
    if not cancelled:
        raise HTTPException(404, "Kein aktiver Prozess gefunden")
    return {"ok": True}


@router.get("/guides/{guide_id}/pdf")
async def download_pdf(guide_id: str):
    guide = await get_guide(guide_id)
    if guide is None:
        raise HTTPException(404, "Guide nicht gefunden")
    if guide["status"] != "done" or not guide["pdf_path"]:
        raise HTTPException(404, "PDF nicht verfügbar")
    path = Path(guide["pdf_path"])
    if not path.exists():
        raise HTTPException(404, "Datei nicht gefunden")
    return FileResponse(path, filename=f"{guide['topic']}-{guide['format']}.pdf", media_type="application/pdf")


@router.delete("/guides/{guide_id}")
async def remove(guide_id: str):
    guide = await get_guide(guide_id)
    if guide is None:
        raise HTTPException(404, "Guide nicht gefunden")
    if guide["html_path"]:
        Path(guide["html_path"]).unlink(missing_ok=True)
    if guide["pdf_path"]:
        Path(guide["pdf_path"]).unlink(missing_ok=True)
    await delete_guide(guide_id)
    return {"ok": True}