import logging

import requests
from celery import shared_task
from django.conf import settings
from django.utils import timezone

logger = logging.getLogger(__name__)


@shared_task(bind=True, max_retries=3, default_retry_delay=60, queue="splat_jobs")
def dispatch_splat_job(self, splat_job_id: str):
    """
    Submit a splatting job to the RunPod serverless endpoint.
    Stores the RunPod job ID on the SplatJob record so incoming
    webhooks can be matched back to it.
    """
    from apps.jobs.models import SplatJob
    from apps.splats.models import Splat
    from apps.utils.storage import generate_presigned_get_url

    try:
        job = SplatJob.objects.select_related("splat").get(id=splat_job_id)
    except SplatJob.DoesNotExist:
        logger.error("SplatJob %s not found", splat_job_id)
        return

    splat = job.splat

    # Generate a time-limited download URL for RunPod to fetch the video
    video_url = generate_presigned_get_url(splat.video_key, expires_in=7200)
    if video_url is None:
        # Development — no real storage, bail out gracefully
        logger.info("Skipping RunPod dispatch in dev (no S3 storage): job %s", splat_job_id)
        return

    webhook_url = f"{settings.API_BASE_URL}/api/v1/jobs/webhook/"

    payload = {
        "input": {
            "video_url": video_url,
            "splat_id": str(splat.id),
            "job_id": str(job.id),
            "webhook_url": webhook_url,
            "webhook_secret": settings.WEBHOOK_SECRET,
        }
    }

    try:
        response = requests.post(
            f"https://api.runpod.io/v2/{settings.RUNPOD_ENDPOINT_ID}/run",
            json=payload,
            headers={"Authorization": f"Bearer {settings.RUNPOD_API_KEY}"},
            timeout=15,
        )
        response.raise_for_status()
    except requests.RequestException as exc:
        logger.exception("RunPod dispatch failed for job %s", splat_job_id)
        raise self.retry(exc=exc)

    runpod_job_id = response.json()["id"]

    SplatJob.objects.filter(pk=job.pk).update(
        runpod_job_id=runpod_job_id,
        status=SplatJob.Status.RUNNING,
        started_at=timezone.now(),
    )
    Splat.objects.filter(pk=splat.pk).update(status=Splat.Status.PROCESSING)

    logger.info("Dispatched RunPod job %s for splat %s", runpod_job_id, splat.id)