import { NODE_LABELS, isEncodingNode } from '~/server/utils/workflow'
import type { Job } from '~/server/utils/jobs'

function classifyError(message: string) {
  const lower = message.toLowerCase()
  if (lower.includes('out of memory') || (lower.includes('cuda') && lower.includes('alloc')) || lower.includes('vram')) {
    return 'ComfyUI VRAM allocation failed. Try Turbo (8 steps) or a smaller aspect ratio.'
  }
  if (lower.includes('econnrefused') || lower.includes('unreachable') || lower.includes('fetch failed')) {
    return 'ComfyUI host connection dropped. Confirm the desktop instance is running and reachable on the LAN.'
  }
  if (lower.includes('timeout')) {
    return 'Network timeout talking to ComfyUI. The job may still be running on the desktop.'
  }
  return message
}

function sleep(ms: number) {
  return new Promise(resolve => setTimeout(resolve, ms))
}

export function watchComfyJob(job: Job): Promise<void> {
  const ws = new WebSocket(comfyWsUrl(job.clientId))
  let settled = false
  let pollTimer: ReturnType<typeof setInterval> | null = null
  let timeout: ReturnType<typeof setTimeout> | null = null

  return new Promise((resolve) => {
    const cleanup = () => {
      if (timeout) clearTimeout(timeout)
      if (pollTimer) clearInterval(pollTimer)
      timeout = null
      pollTimer = null
      try { ws.close() } catch { /* ignore */ }
    }

    const fail = async (error: string) => {
      if (settled) return
      settled = true
      cleanup()
      job.status = job.status === 'cancelled' ? 'cancelled' : 'error'
      job.error = classifyError(error)
      emitJob(job, { type: 'error', error: job.error, message: job.error })
      if (job.id) deletePendingJob(job.id)
      resolve()
    }

    const succeed = async () => {
      if (settled || !job.promptId) return false
      const history = await fetchHistory(job.promptId)
      const video = extractVideo(history, job.promptId)
      if (!video) return false
      settled = true
      cleanup()
      try {
        job.video = video
        emitJob(job, { type: 'status', message: 'Saving to library...', progress: 98 })
        if (job.library) {
          const buffer = await downloadComfyVideo(video)
          const clip = await saveClip({
            ownerKey: job.library.ownerKey,
            folderId: job.library.folderId,
            name: job.library.name,
            prompt: job.library.prompt,
            aspect: job.library.aspect,
            width: job.library.width,
            height: job.library.height,
            steps: job.library.steps,
            turbo: job.library.turbo,
            seed: job.library.seed,
            hideThumbnail: job.library.hideThumbnail,
            hideInput: job.library.hideInput,
            video: buffer,
            thumb: job.library.thumb,
            comfyFilename: video.filename
          })
          job.clipId = clip.id
          job.hideThumbnail = clip.hideThumbnail
          job.library.thumb = undefined
          await purgeComfyArtifacts({
            video,
            imageName: job.library.imageName,
            imageSubfolder: job.library.imageSubfolder,
            promptId: job.promptId
          })
        }
        job.status = 'complete'
        emitJob(job, {
          type: 'complete',
          message: job.library?.folderLocked ? 'Saved to the locked folder. Unlock it to view.' : 'Video ready',
          progress: 100,
          filename: job.library?.folderLocked ? undefined : video.filename,
          subfolder: job.library?.folderLocked ? undefined : video.subfolder,
          mediaType: job.library?.folderLocked ? undefined : video.type,
          clipId: job.clipId,
          hideThumbnail: job.hideThumbnail,
          folderLocked: job.library?.folderLocked
        })
        deletePendingJob(job.id)
      } catch (saveError) {
        const message = saveError instanceof Error ? saveError.message : String(saveError)
        job.status = 'error'
        job.error = `Video generated but library save failed: ${message}`
        emitJob(job, { type: 'error', error: job.error, message: job.error })
      }
      resolve()
      return true
    }

    let dropMisses = 0

    const pollHistory = async () => {
      if (settled || !job.promptId) return
      try {
        const inspected = inspectHistory(await fetchHistory(job.promptId), job.promptId)
        if (inspected.error) {
          await fail(inspected.error)
          return
        }
        if (inspected.video) {
          await succeed()
          return
        }
        if (await isComfyPromptDropped(job.promptId)) {
          dropMisses += 1
          if (dropMisses >= 3) {
            await fail('ComfyUI dropped this job. Reloading the Comfy interface clears the queue. Generate again.')
          }
        } else {
          dropMisses = 0
        }
      } catch {
        // Transient ComfyUI history misses are expected while the graph is still running.
      }
    }

    timeout = setTimeout(() => {
      void fail('Timed out waiting for ComfyUI (15 minutes).')
    }, 15 * 60 * 1000)

    pollTimer = setInterval(() => {
      void pollHistory()
    }, 2000)

    ws.addEventListener('open', () => {
      job.socketReady = true
      emitJob(job, { type: 'status', message: 'Connected to ComfyUI', progress: Math.max(job.progress, 4) })
    })

    ws.addEventListener('close', () => {
      if (settled || !job.promptId) return
      void pollHistory()
    })

    ws.addEventListener('message', async (event) => {
      let payload: { type?: string; data?: Record<string, unknown> }
      try {
        payload = JSON.parse(String(event.data))
      } catch {
        return
      }
      const data = payload.data || {}
      if (job.promptId && data.prompt_id && data.prompt_id !== job.promptId) return

      if (payload.type === 'progress') {
        const value = Number(data.value || 0)
        const max = Number(data.max || 1)
        const pct = 12 + Math.round((value / Math.max(max, 1)) * 70)
        job.status = 'running'
        emitJob(job, {
          type: 'progress',
          step: value,
          maxStep: max,
          progress: pct,
          node: data.node ? String(data.node) : null,
          message: `Sampling step ${value}/${max} (${Math.round((value / Math.max(max, 1)) * 100)}%)`
        })
      }

      if (payload.type === 'executing') {
        const node = data.node === null || data.node === undefined ? null : String(data.node)
        if (node === null) {
          const saved = await succeed()
          if (!saved) {
            emitJob(job, { type: 'status', message: 'Waiting for ComfyUI to save the MP4...', progress: 96 })
          }
          return
        }
        const label = NODE_LABELS[node] || `Running node ${node}`
        const encoding = isEncodingNode(node)
        emitJob(job, {
          type: 'executing',
          node,
          progress: encoding ? 90 : Math.max(job.progress, 10),
          message: encoding ? 'Encoding video...' : `${label}...`
        })
      }

      if (payload.type === 'execution_error') {
        const message = String(data.exception_message || data.message || 'ComfyUI node execution failed')
        await fail(message)
      }

      if (payload.type === 'execution_interrupted') {
        job.status = 'cancelled'
        await fail('Job interrupted.')
      }
    })
  })
}

export async function waitForComfySocket(job: Job, ms = 4000) {
  const started = Date.now()
  while (Date.now() - started < ms) {
    if (job.socketReady) return
    await sleep(100)
  }
}