import { Worker } from "bullmq";
import path from "path";
import { JobItemStatus, JobStatus } from "@prisma/client";
import { QUEUE_NAME } from "../lib/constants";
import { prisma } from "../lib/db";
import { cleanupFiles, encodeVideo, getFfmpegPath } from "../lib/ffmpeg/encode";
import { getRedisConnection } from "../lib/queue/client";
import { releaseReservation } from "../lib/quota";
import { getJobDir } from "../lib/storage";
import type { VideoJobData } from "../lib/types";
import { formatYouTubeErrorForUser } from "../lib/youtube/errors";
import { uploadToYouTube } from "../lib/youtube/upload";

async function updateJobStatus(jobId: string) {
  const items = await prisma.jobItem.findMany({ where: { jobId } });
  const completed = items.filter((i) => i.status === JobItemStatus.COMPLETED).length;
  const failed = items.filter((i) => i.status === JobItemStatus.FAILED).length;
  const total = items.length;

  let status: JobStatus = JobStatus.PROCESSING;
  if (completed + failed === total) {
    if (completed === total) status = JobStatus.COMPLETED;
    else if (failed === total) status = JobStatus.FAILED;
    else status = JobStatus.PARTIAL;
  }

  await prisma.job.update({
    where: { id: jobId },
    data: {
      status,
      completedAt: completed + failed === total ? new Date() : null,
    },
  });
}

async function processJobItem(data: VideoJobData) {
  const item = await prisma.jobItem.findUniqueOrThrow({
    where: { id: data.jobItemId },
    include: { job: true },
  });

  if (item.job.userId !== data.userId || item.jobId !== data.jobId) {
    const message = "Job ownership mismatch";
    console.error(`[security] ${message} for item ${item.id}`);
    await prisma.jobItem.update({
      where: { id: item.id },
      data: { status: JobItemStatus.FAILED, error: message },
    });
    await releaseReservation(item.job.userId, item.billingSource, 1).catch(() => {});
    await updateJobStatus(item.jobId);
    throw new Error(message);
  }

  const jobDir = getJobDir(data.userId, data.jobId);
  const outputPath = path.join(jobDir, `${item.id}.mp4`);

  try {
    await prisma.jobItem.update({
      where: { id: item.id },
      data: { status: JobItemStatus.ENCODING },
    });
    await prisma.job.update({
      where: { id: data.jobId },
      data: { status: JobStatus.PROCESSING },
    });

    await encodeVideo({
      imagePath: item.job.imagePath,
      audioPath: item.audioPath,
      outputPath,
      resolution: item.resolution,
      includeWatermark: item.includeWatermark,
    });

    await prisma.jobItem.update({
      where: { id: item.id },
      data: { status: JobItemStatus.UPLOADING, outputPath },
    });

    const youtubeVideoId = await uploadToYouTube(data.userId, outputPath, item);

    await prisma.jobItem.update({
      where: { id: item.id },
      data: {
        status: JobItemStatus.COMPLETED,
        youtubeVideoId,
        error: null,
      },
    });

    // Quota was reserved at job creation; do not increment again on success.
    await cleanupFiles([outputPath]);
  } catch (err) {
    const message = formatYouTubeErrorForUser(err);
    console.error(`[youtube] Job item ${item.id} ("${item.title}") failed: ${message}`);
    await prisma.jobItem.update({
      where: { id: item.id },
      data: { status: JobItemStatus.FAILED, error: message },
    });
    await releaseReservation(data.userId, item.billingSource, 1).catch(() => {});
    throw new Error(message);
  } finally {
    await updateJobStatus(data.jobId);
  }
}

const worker = new Worker<VideoJobData>(
  QUEUE_NAME,
  async (job) => {
    await processJobItem(job.data);
  },
  {
    connection: getRedisConnection(),
    concurrency: 2,
  },
);

worker.on("completed", (job) => {
  console.log(`Job item ${job.data.jobItemId} completed`);
});

worker.on("failed", (job, err) => {
  console.error(`Job item ${job?.data.jobItemId} failed:`, err.message);
});

console.log(`Songs2YT worker started (ffmpeg: ${getFfmpegPath()}), waiting for jobs...`);