import { createReadStream, existsSync, mkdirSync, readdirSync, readFileSync, writeFileSync, renameSync, unlinkSync } from 'node:fs'
import { join } from 'node:path'
import { createJob, emitJob, getJob, restoreJob, type Job } from './jobs'
import { getStill, stillPath } from './library'
import { sharedGpuHeaders } from './sharedGpu'
import { CAPTION_STYLES } from '~/shared/studio2/caption.mjs'

function settings() {
  const config = useRuntimeConfig()
  return {
    url: String(config.comfyControlUrl || process.env.COMFY_CONTROL_URL || '').replace(/\/$/, ''),
    token: String(config.comfyControlToken || process.env.COMFY_CONTROL_TOKEN || '')
  }
}

export function captionConfigured() { return Boolean(settings().url) }

function pendingRoot() {
  return join(String(useRuntimeConfig().libraryDir || process.env.LIBRARY_DIR || '/data/library'), 'caption-pending')
}

export function captionPendingAlive(jobId: string) {
  if (!jobId) return false
  return existsSync(join(pendingRoot(), `${jobId}.json`))
}

async function request(path: string, method = 'GET', body?: unknown) {
  const { url, token } = settings()
  if (!url) throw new Error('Caption host is not configured. Set COMFY_CONTROL_URL.')
  const response = await fetch(`${url}/caption/${path}`, {
    method,
    headers: {
      ...(token ? { Authorization: `Bearer ${token}` } : {}),
      ...(method === 'GET' ? {} : sharedGpuHeaders()),
      ...(method === 'POST' ? { 'Content-Type': 'application/json' } : {})
    },
    body: method === 'POST' ? JSON.stringify(body) : body as BodyInit | undefined,
    ...(method === 'PUT' ? { duplex: 'half' as const } : {}),
    signal: AbortSignal.timeout(method === 'PUT' ? 120_000 : 60_000)
  } as RequestInit)
  if (!response.ok) {
    const detail = await response.json().catch(() => ({})) as { message?: string; error?: string }
    throw Object.assign(new Error(detail.message || detail.error || `Caption host returned ${response.status}`), { statusCode: response.status })
  }
  return response
}

function persist(record: Record<string, unknown>) {
  mkdirSync(pendingRoot(), { recursive: true })
  const path = join(pendingRoot(), `${record.id}.json`)
  writeFileSync(path + '.tmp', JSON.stringify(record))
  renameSync(path + '.tmp', path)
}

function clearPending(id: string) {
  const path = join(pendingRoot(), `${id}.json`)
  if (existsSync(path)) unlinkSync(path)
}

function writeSidecar(owner: string, stillId: string, text: string) {
  try {
    const image = stillPath(owner, stillId)
    if (!existsSync(image)) return
    writeFileSync(`${image}.txt`, text, 'utf8')
  } catch { /* optional sidecar */ }
}

export async function cancelCaptionJob(job: Job) {
  await request(`jobs/${job.id}/cancel`, 'POST', {})
  job.status = 'cancelled'
  emitJob(job, { type: 'error', error: 'Cancelled', message: 'Cancelled' })
}

async function settle(job: Job) {
  const { onLiveVideoSettled } = await import('./studioQueue')
  await onLiveVideoSettled(job)
  clearPending(job.id)
}

async function watch(job: Job, record: {
  id: string
  owner: string
  stillId: string
  folderId: string
  captionStyle: string
  studio2Id?: string
  liveId: string
}) {
  let failures = 0
  while (job.status !== 'cancelled') {
    try {
      const state = await (await request(`jobs/${job.id}`)).json() as {
        status: string
        message?: string
        error?: string
        progress?: number
        text?: string
      }
      if (job.status === 'cancelled') { await settle(job); return }
      if (state.status === 'error' || state.status === 'cancelled') {
        job.status = state.status === 'cancelled' ? 'cancelled' : 'error'
        job.error = state.error || state.message || 'Caption failed'
        emitJob(job, { type: 'error', error: job.error, message: job.error })
        if (record.studio2Id) {
          const { readRecord, saveRecord } = await import('./studio2/store')
          try {
            const r = readRecord(record.owner, record.studio2Id)
            r.state = job.status === 'cancelled' ? 'cancelled' : 'failed'
            r.error = job.error
            r.finishedAt = Date.now()
            saveRecord(r)
          } catch { /* record may already be gone */ }
        }
        await settle(job)
        return
      }
      if (state.status === 'complete') {
        const text = String(state.text || '').trim()
        job.message = 'Caption ready'
        job.progress = 100
        job.status = 'complete'
        ;(job as Job & { resultText?: string }).resultText = text
        if (record.studio2Id) {
          const { readRecord, saveRecord } = await import('./studio2/store')
          const r = readRecord(record.owner, record.studio2Id)
          r.state = 'complete'
          r.resultText = text
          r.finishedAt = Date.now()
          r.savedAt = Date.now()
          saveRecord(r)
        }
        writeSidecar(record.owner, record.stillId, text)
        emitJob(job, { type: 'complete', message: 'Caption ready', progress: 100 })
        await settle(job)
        return
      }
      failures = 0
      job.status = 'running'
      emitJob(job, {
        type: 'progress',
        message: state.message || 'Captioning',
        progress: Math.min(95, Math.max(1, Number(state.progress || 10)))
      })
    } catch (error) {
      failures++
      emitJob(job, { type: 'status', message: `Caption host check failed; retrying: ${error instanceof Error ? error.message : String(error)}` })
      if (failures >= 10) {
        job.status = 'error'
        job.error = 'Caption host unreachable.'
        emitJob(job, { type: 'error', error: job.error, message: job.error })
        await settle(job)
        return
      }
    }
    await new Promise(resolve => setTimeout(resolve, 1500))
  }
  await settle(job)
}

export async function startCaptionJob(params: {
  ownerKey: string
  folderId: string
  stillId: string
  captionStyle: string
  studio2Id?: string
  name?: string
}) {
  if (!CAPTION_STYLES.includes(params.captionStyle)) throw new Error('Unknown caption style.')
  getStill(params.ownerKey, params.stillId)
  const job = createJob('caption')
  job.caption = true
  job.library = {
    ownerKey: params.ownerKey,
    folderId: params.folderId,
    hideThumbnail: false,
    name: params.name || `Describe · ${params.captionStyle}`,
    prompt: params.captionStyle,
    aspect: 'image',
    width: 0,
    height: 0,
    steps: 1,
    turbo: true,
    seed: 0,
    stillId: params.stillId,
    engine: 'caption'
  }
  const record = {
    id: job.id,
    liveId: job.id,
    owner: params.ownerKey,
    stillId: params.stillId,
    folderId: params.folderId,
    captionStyle: params.captionStyle,
    studio2Id: params.studio2Id,
    createdAt: Date.now(),
    status: 'running'
  }
  persist(record)
  void (async () => {
    try {
      if (job.status === 'cancelled') { await settle(job); return }
      await request(`jobs/${job.id}/input`, 'PUT', createReadStream(stillPath(params.ownerKey, params.stillId)))
      if (job.status === 'cancelled') { await settle(job); return }
      try {
        await request('jobs', 'POST', { id: job.id, style: params.captionStyle })
      } catch {
        /* Confirm by ID; never caption twice on an HTTP timeout. */
      }
      await watch(job, record)
    } catch (error) {
      const statusCode = (error as { statusCode?: number })?.statusCode
      if (statusCode && statusCode >= 400 && statusCode < 500) {
        job.status = 'error'
        job.error = error instanceof Error ? error.message : String(error)
        emitJob(job, { type: 'error', error: job.error, message: job.error })
        if (params.studio2Id) {
          try {
            const { readRecord, saveRecord } = await import('./studio2/store')
            const r = readRecord(params.ownerKey, params.studio2Id)
            r.state = 'failed'
            r.error = job.error
            r.finishedAt = Date.now()
            saveRecord(r)
          } catch { /* ignore */ }
        }
        await settle(job)
        return
      }
      emitJob(job, { type: 'status', message: `Checking caption submission: ${error instanceof Error ? error.message : String(error)}` })
      await watch(job, record)
    }
  })()
  return job
}

export function resumeCaptionJobs() {
  if (!existsSync(pendingRoot())) return
  for (const file of readdirSync(pendingRoot()).filter(file => /^[a-zA-Z0-9-]+\.json$/.test(file))) {
    try {
      const record = JSON.parse(readFileSync(join(pendingRoot(), file), 'utf8'))
      if (getJob(record.id)) continue
      const job = restoreJob({
        id: record.liveId || record.id,
        clientId: record.clientId || crypto.randomUUID(),
        promptId: '',
        startedAt: record.createdAt || Date.now(),
        library: {
          ownerKey: record.owner,
          folderId: record.folderId,
          hideThumbnail: false,
          prompt: record.captionStyle || 'descriptive',
          aspect: 'image',
          width: 0,
          height: 0,
          steps: 1,
          turbo: true,
          seed: 0,
          stillId: record.stillId,
          engine: 'caption'
        }
      })
      job.caption = true
      job.kind = 'caption'
      job.message = 'Reconnecting to caption host'
      void watch(job, record)
    } catch { /* Preserve invalid records for diagnosis. */ }
  }
}