import io
import json

from django.contrib.auth.decorators import login_required
from django.http import FileResponse, JsonResponse
from django.shortcuts import get_object_or_404
from django.views.decorators.http import require_GET, require_POST

from core.campaign_utm import resolve_campaign_tracked_url
from core.models import StoredFile


def healthz(_request):
    """Liveness probe for deploy / NPM health checks."""
    return JsonResponse({"status": "ok"})


@require_GET
def stored_file(request, pk):
    """Public fetch (UUID acts as capability token)."""
    stored = get_object_or_404(StoredFile, pk=pk)
    response = FileResponse(
        io.BytesIO(bytes(stored.data)),
        content_type=stored.content_type or "application/octet-stream",
    )
    if stored.filename:
        response["Content-Disposition"] = f'inline; filename="{stored.filename}"'
    response["Cache-Control"] = "public, max-age=86400"
    return response


@login_required
@require_POST
def campaign_short_link(request):
    """Mint (or reuse) a short URL for the campaign tracked landing link.

    Browser talks to this portal endpoint only. The shortener is server-to-server.
    Does not import optional campaign apps — campaign_id is only an external_ref.
    """
    try:
        payload = json.loads(request.body.decode() or "{}")
    except (json.JSONDecodeError, UnicodeDecodeError):
        payload = {}
    if not isinstance(payload, dict):
        payload = {}
    name = (payload.get("name") or request.POST.get("name") or "").strip()
    medium = (payload.get("medium") or request.POST.get("medium") or "").strip()
    campaign_id = (
        payload.get("campaign_id") or request.POST.get("campaign_id") or ""
    )
    campaign_id = str(campaign_id).strip() or None
    target, display = resolve_campaign_tracked_url(
        name=name or "campaign",
        medium=medium,
        campaign_id=campaign_id,
        user_id=getattr(request.user, "pk", None),
        shorten=True,
    )
    return JsonResponse(
        {
            "target_url": target,
            "short_url": display if display != target else "",
            "display_url": display,
            "shortened": display != target,
        }
    )