import { NextRequest, NextResponse } from 'next/server'
import { getServerSession } from 'next-auth'
import { authOptions } from '@/lib/auth'
import { transcodeQueue } from '@/lib/video-transcode-queue'

export const dynamic = 'force-dynamic'

const DEFAULT_PREVIEW_LIMIT = 20
const MAX_PREVIEW_LIMIT = 100

export async function GET(request: NextRequest) {
  try {
    const session = await getServerSession(authOptions)

    const role = (session?.user as unknown as { role?: string } | null)?.role
    if (!session || role !== 'ADMIN') {
      return NextResponse.json({ error: '无权限' }, { status: 403 })
    }

    const { searchParams } = new URL(request.url)
    const limitParam = searchParams.get('limit')
    let previewLimit = Number.parseInt(limitParam || '', 10)
    if (Number.isNaN(previewLimit) || previewLimit <= 0) {
      previewLimit = DEFAULT_PREVIEW_LIMIT
    } else {
      previewLimit = Math.min(previewLimit, MAX_PREVIEW_LIMIT)
    }

    const status = transcodeQueue.getStatus()

    const processingPreview = status.processingIds.slice(0, previewLimit)
    const waitingPreview = status.waiting.slice(0, previewLimit)
    const progressSnapshot = Array.from(status.progress.entries())
      .slice(0, previewLimit)
      .map(([materialId, value]) => ({
        materialId,
        progress: value,
        stage: status.stages.get(materialId) ?? null,
      }))

    return NextResponse.json({
      queueLength: status.queueLength,
      processingCount: status.processingCount,
      maxConcurrent: status.maxConcurrent,
      processingPreview,
      waitingPreview,
      previewLimit,
      timestamp: new Date().toISOString(),
      progress: progressSnapshot,
    })
  } catch (error) {
    console.error('[Admin] Video transcode queue status error:', error)
    return NextResponse.json({ error: '获取转码队列状态失败' }, { status: 500 })
  }
}