import { existsSync, mkdirSync, readdirSync, readFileSync, renameSync, rmSync, writeFileSync } from 'node:fs'
import { join } from 'node:path'

export interface PendingJob {
  jobId: string
  promptId: string
  clientId: string
  ownerKey: string
  folderId: string
  hideThumbnail: boolean
  folderLocked?: boolean
  name?: string
  prompt: string
  aspect: string
  width: number
  height: number
  steps: number
  turbo: boolean
  seed: number
  startedAt: number
  imageName?: string
  imageSubfolder?: string
  extendTmpDir?: string
  extendPart1Path?: string
}

function pendingRoot() {
  const config = useRuntimeConfig()
  return join((config.libraryDir || process.env.LIBRARY_DIR || '/data/library').replace(/\/$/, ''), 'pending')
}

function pendingPath(jobId: string) {
  return join(pendingRoot(), `${jobId}.json`)
}

function ensurePending() {
  mkdirSync(pendingRoot(), { recursive: true })
}

export function writePendingJob(job: PendingJob) {
  ensurePending()
  const tmp = pendingPath(job.jobId) + '.tmp'
  writeFileSync(tmp, JSON.stringify(job, null, 2))
  renameSync(tmp, pendingPath(job.jobId))
}

export function readPendingJob(jobId: string): PendingJob | null {
  const path = pendingPath(jobId)
  if (!existsSync(path)) return null
  try {
    return JSON.parse(readFileSync(path, 'utf8')) as PendingJob
  } catch {
    return null
  }
}

export function listPendingJobs(): PendingJob[] {
  ensurePending()
  return readdirSync(pendingRoot())
    .filter(name => name.endsWith('.json'))
    .map(name => readPendingJob(name.replace(/\.json$/, '')))
    .filter((job): job is PendingJob => Boolean(job))
}

export function deletePendingJob(jobId: string) {
  rmSync(pendingPath(jobId), { force: true })
}

export async function completePendingIfReady(pending: PendingJob) {
  const history = await fetchHistory(pending.promptId)
  const video = extractVideo(history, pending.promptId)
  if (!video) return null
  let buffer = await downloadComfyVideo(video)
  if (pending.extendPart1Path && pending.extendTmpDir) {
    if (!existsSync(pending.extendPart1Path)) {
      removeExtendTemp(pending.extendTmpDir)
      throw createError({ statusCode: 500, statusMessage: 'Extension source clip was missing during stitch' })
    }
    try {
      buffer = await stitchExtension({
        part1Path: pending.extendPart1Path,
        part2: buffer,
        tmpDir: pending.extendTmpDir
      })
    } catch (error) {
      removeExtendTemp(pending.extendTmpDir)
      throw error
    }
    removeExtendTemp(pending.extendTmpDir)
  }
  const clip = await saveClip({
    ownerKey: pending.ownerKey,
    folderId: pending.folderId,
    name: pending.name,
    prompt: pending.prompt,
    aspect: pending.aspect,
    width: pending.width,
    height: pending.height,
    steps: pending.steps,
    turbo: pending.turbo,
    seed: pending.seed,
    hideThumbnail: pending.hideThumbnail,
    video: buffer,
    thumb: null,
    comfyFilename: video.filename
  })
  await purgeComfyArtifacts({ video, imageName: pending.imageName, imageSubfolder: pending.imageSubfolder, promptId: pending.promptId })
  deletePendingJob(pending.jobId)
  return {
    type: 'complete' as const,
    status: 'complete' as const,
    message: pending.folderLocked
      ? 'Saved to the locked folder. Unlock it to view.'
      : (pending.extendPart1Path ? 'Extended video ready' : 'Video ready'),
    progress: 100,
    jobId: pending.jobId,
    clipId: clip.id,
    filename: pending.folderLocked ? undefined : video.filename,
    subfolder: pending.folderLocked ? undefined : video.subfolder,
    mediaType: pending.folderLocked ? undefined : video.type,
    hideThumbnail: pending.hideThumbnail,
    folderLocked: pending.folderLocked
  }
}

export async function resolvePendingJob(pending: PendingJob) {
  const done = await completePendingIfReady(pending)
  if (done) return done
  if (await isComfyPromptDropped(pending.promptId)) {
    deletePendingJob(pending.jobId)
    const message = 'ComfyUI dropped this job. Reloading the Comfy interface clears the queue. Generate again.'
    return {
      type: 'error' as const,
      status: 'error' as const,
      jobId: pending.jobId,
      error: message,
      message,
      progress: 0
    }
  }
  return null
}