import fs from 'fs';
import { NextResponse } from 'next/server';
import { transcodeOrchestrator } from '@/lib/transcode/orchestrator';
import { segmentPath } from '@/lib/transcode/playlist';

export const runtime = 'nodejs';
export const dynamic = 'force-dynamic';

async function waitForSegment(filePath: string, timeoutMs = 5000): Promise<boolean> {
  const startedAt = Date.now();
  while (Date.now() - startedAt < timeoutMs) {
    if (fs.existsSync(filePath)) {
      const stat = fs.statSync(filePath);
      if (stat.size > 0) return true;
    }
    await new Promise(resolve => setTimeout(resolve, 150));
  }
  return false;
}

export async function GET(_request: Request, { params }: { params: Promise<{ jobId: string; name: string }> }) {
  const { jobId, name } = await params;
  const job = transcodeOrchestrator.get(jobId);

  if (!job) {
    return NextResponse.json({ error: 'Transcode job not found' }, { status: 404 });
  }

  const resolvedPath = segmentPath(job.outDir, name);
  if (!resolvedPath || !(await waitForSegment(resolvedPath))) {
    return new Response(null, { status: 404 });
  }

  const stat = fs.statSync(resolvedPath);
  const stream = fs.createReadStream(resolvedPath);
  return new Response(stream as any, {
    status: 200,
    headers: {
      'Content-Type': 'video/mp2t',
      'Content-Length': stat.size.toString(),
      'Cache-Control': 'private, max-age=3600',
      'ETag': `"${jobId}-${name}-${stat.size}-${stat.mtimeMs}"`,
      'Access-Control-Allow-Origin': '*',
    },
  });
}