import {
  FFmpegContainer,
  ffprobePromise,
  getVideoStreamDimensionsInfo,
  getVideoStreamFPS,
  hasAudioStream,
  hasVideoStream,
  isAudioFile
} from '@peertube/peertube-ffmpeg'
import { FileStorage, VideoFileFormatFlag, VideoFileMetadata, VideoFileStream, VideoResolution } from '@peertube/peertube-models'
import { getFileSize, getLowercaseExtension } from '@peertube/peertube-node-utils'
import { getFFmpegCommandWrapperOptions } from '@server/helpers/ffmpeg/ffmpeg-options.js'
import { logger, loggerTagsFactory } from '@server/helpers/logger.js'
import { doRequestAndSaveToFile, generateRequestStream } from '@server/helpers/requests.js'
import { CONFIG } from '@server/initializers/config.js'
import { MIMETYPES, REQUEST_TIMEOUTS } from '@server/initializers/constants.js'
import { VideoFileModel } from '@server/models/video/video-file.js'
import { VideoSourceModel } from '@server/models/video/video-source.js'
import { MVideo, MVideoFile, MVideoId, MVideoThumbnail, MVideoWithAllFiles } from '@server/types/models/index.js'
import { FfprobeData } from 'fluent-ffmpeg'
import { move, remove } from 'fs-extra/esm'
import { Readable, Writable } from 'stream'
import { lTags } from './object-storage/shared/index.js'
import {
  getHLSFileReadStream,
  getWebVideoFileReadStream,
  makeHLSFileAvailable,
  makeWebVideoFileAvailable,
  storeOriginalVideoFile
} from './object-storage/videos.js'
import { generateHLSVideoFilename, generateWebVideoFilename } from './paths.js'
import { VideoPathManager } from './video-path-manager.js'

export async function buildNewFile (options: {
  path: string
  mode: 'web-video' | 'hls'
  ffprobe?: FfprobeData
}): Promise<MVideoFile> {
  const { path, mode, ffprobe: probeArg } = options

  const probe = probeArg ?? await ffprobePromise(path)
  const size = await getFileSize(path)

  const videoFile = new VideoFileModel({
    extname: getLowercaseExtension(path),
    size,
    metadata: await buildFileMetadata(path, probe),

    streams: VideoFileStream.NONE,

    formatFlags: mode === 'web-video'
      ? VideoFileFormatFlag.WEB_VIDEO
      : VideoFileFormatFlag.FRAGMENTED
  })

  if (await hasAudioStream(path, probe)) {
    videoFile.streams |= VideoFileStream.AUDIO
  }

  if (await hasVideoStream(path, probe)) {
    videoFile.streams |= VideoFileStream.VIDEO
  }

  if (await isAudioFile(path, probe)) {
    videoFile.fps = 0
    videoFile.resolution = VideoResolution.H_NOVIDEO
    videoFile.width = 0
    videoFile.height = 0
  } else {
    const dimensions = await getVideoStreamDimensionsInfo(path, probe)
    videoFile.fps = await getVideoStreamFPS(path, probe)
    videoFile.resolution = dimensions.resolution
    videoFile.width = dimensions.width
    videoFile.height = dimensions.height
  }

  videoFile.filename = mode === 'web-video'
    ? generateWebVideoFilename(videoFile.resolution, videoFile.extname)
    : generateHLSVideoFilename(videoFile.resolution)

  return videoFile
}

// ---------------------------------------------------------------------------

export async function removeHLSPlaylist (video: MVideoWithAllFiles) {
  const hls = video.getHLSPlaylist()
  if (!hls) return

  const videoFileMutexReleaser = await VideoPathManager.Instance.lockFiles(video.uuid)

  try {
    await video.removeStreamingPlaylistFiles(hls)
    await hls.destroy()

    video.VideoStreamingPlaylists = video.VideoStreamingPlaylists.filter(p => p.id !== hls.id)
  } finally {
    videoFileMutexReleaser()
  }
}

export async function removeHLSFile (video: MVideoWithAllFiles, fileToDeleteId: number) {
  const hls = video.getHLSPlaylist()
  const files = hls.VideoFiles

  if (files.length === 1) {
    await removeHLSPlaylist(video)
    return undefined
  }

  const videoFileMutexReleaser = await VideoPathManager.Instance.lockFiles(video.uuid)

  try {
    const toDelete = files.find(f => f.id === fileToDeleteId)
    await video.removeStreamingPlaylistVideoFile(video.getHLSPlaylist(), toDelete)
    await toDelete.destroy()

    hls.VideoFiles = hls.VideoFiles.filter(f => f.id !== toDelete.id)
  } finally {
    videoFileMutexReleaser()
  }

  return hls
}

// ---------------------------------------------------------------------------

export async function removeAllWebVideoFiles (video: MVideoWithAllFiles) {
  const videoFileMutexReleaser = await VideoPathManager.Instance.lockFiles(video.uuid)

  try {
    for (const file of video.VideoFiles) {
      await video.removeWebVideoFile(file)
      await file.destroy()
    }

    video.VideoFiles = []
  } finally {
    videoFileMutexReleaser()
  }

  return video
}

export async function removeWebVideoFile (video: MVideoWithAllFiles, fileToDeleteId: number) {
  const files = video.VideoFiles

  if (files.length === 1) {
    return removeAllWebVideoFiles(video)
  }

  const videoFileMutexReleaser = await VideoPathManager.Instance.lockFiles(video.uuid)
  try {
    const toDelete = files.find(f => f.id === fileToDeleteId)
    await video.removeWebVideoFile(toDelete)
    await toDelete.destroy()

    video.VideoFiles = files.filter(f => f.id !== toDelete.id)
  } finally {
    videoFileMutexReleaser()
  }

  return video
}

// ---------------------------------------------------------------------------

export async function buildFileMetadata (path: string, existingProbe?: FfprobeData) {
  const metadata = existingProbe || await ffprobePromise(path)

  return new VideoFileMetadata(metadata)
}

export function getVideoFileMimeType (extname: string, isAudio: boolean) {
  return isAudio && extname === '.mp4' // We use .mp4 even for audio file only
    ? MIMETYPES.AUDIO.EXT_MIMETYPE['.m4a']
    : MIMETYPES.VIDEO.EXT_MIMETYPE[extname]
}

// ---------------------------------------------------------------------------

export async function createVideoSource (options: {
  inputFilename: string
  inputProbe: FfprobeData
  inputPath: string
  video: MVideoId
  createdAt?: Date
}) {
  const { inputFilename, inputPath, inputProbe, video, createdAt } = options

  const videoSource = new VideoSourceModel({
    inputFilename,
    videoId: video.id,
    createdAt
  })

  if (inputPath) {
    const probe = inputProbe ?? await ffprobePromise(inputPath)

    if (await isAudioFile(inputPath, probe)) {
      videoSource.fps = 0
      videoSource.resolution = VideoResolution.H_NOVIDEO
      videoSource.width = 0
      videoSource.height = 0
    } else {
      const dimensions = await getVideoStreamDimensionsInfo(inputPath, probe)
      videoSource.fps = await getVideoStreamFPS(inputPath, probe)
      videoSource.resolution = dimensions.resolution
      videoSource.width = dimensions.width
      videoSource.height = dimensions.height
    }

    videoSource.metadata = await buildFileMetadata(inputPath, probe)
    videoSource.size = await getFileSize(inputPath)
  }

  return videoSource.save()
}

export async function saveNewOriginalFileIfNeeded (video: MVideo, videoFile: MVideoFile) {
  if (!CONFIG.TRANSCODING.ORIGINAL_FILE.KEEP) return

  const videoSource = await VideoSourceModel.loadLatest(video.id)

  // Already have saved an original file
  if (!videoSource || videoSource.keptOriginalFilename) return
  videoSource.keptOriginalFilename = videoFile.filename

  const lTags = loggerTagsFactory(video.uuid)

  logger.info(`Storing original video file ${videoSource.keptOriginalFilename} of video ${video.name}`, lTags())

  const sourcePath = VideoPathManager.Instance.getFSVideoFileOutputPath(video, videoFile)

  if (CONFIG.OBJECT_STORAGE.ENABLED) {
    const fileUrl = await storeOriginalVideoFile(sourcePath, videoSource.keptOriginalFilename)
    await remove(sourcePath)

    videoSource.storage = FileStorage.OBJECT_STORAGE
    videoSource.fileUrl = fileUrl
  } else {
    const destinationPath = VideoPathManager.Instance.getFSOriginalVideoFilePath(videoSource.keptOriginalFilename)
    await move(sourcePath, destinationPath)

    videoSource.storage = FileStorage.FILE_SYSTEM
  }

  await videoSource.save()

  // Delete previously kept video files
  const allSources = await VideoSourceModel.listAll(video.id)
  for (const oldSource of allSources) {
    if (!oldSource.keptOriginalFilename) continue
    if (oldSource.id === videoSource.id) continue

    try {
      await video.removeOriginalFile(oldSource)
    } catch (err) {
      logger.error('Cannot delete old original file ' + oldSource.keptOriginalFilename, { err, ...lTags() })
    }
  }
}

// ---------------------------------------------------------------------------

export async function muxToMergeVideoFiles (options: {
  video: MVideoThumbnail
  videoFiles: MVideoFile[]
  output: Writable
}) {
  const { video, videoFiles, output } = options

  const inputs: (string | Readable)[] = []
  const tmpDestinations: string[] = []

  try {
    let maxResolution = 0

    for (const videoFile of videoFiles) {
      if (!videoFile) continue

      maxResolution = Math.max(maxResolution, videoFile.resolution)

      const { input, isTmpDestination } = await buildMuxInput(video, videoFile)

      inputs.push(input)

      if (isTmpDestination === true) tmpDestinations.push(input)
    }

    // Include cover to audio file?
    const { coverPath, isTmpDestination } = maxResolution === 0
      ? await buildCoverInput(video)
      : { coverPath: undefined, isTmpDestination: false }

    if (coverPath && isTmpDestination) tmpDestinations.push(coverPath)

    const inputsToLog = inputs.map(i => {
      if (typeof i === 'string') return i

      return 'ReadableStream'
    })

    logger.info(`Muxing files for video ${video.url}`, { inputs: inputsToLog, ...lTags(video.uuid) })

    try {
      await new FFmpegContainer(getFFmpegCommandWrapperOptions('vod')).mergeInputs({
        inputs,
        output,
        logError: true,

        // Include a cover if this is an audio file
        coverPath
      })

      logger.info(`Mux ended for video ${video.url}`, { inputs: inputsToLog, ...lTags(video.uuid) })
    } catch (err) {
      const message = err?.message || ''

      if (message.includes('Output stream closed')) {
        logger.info(`Client aborted mux for video ${video.url}`, lTags(video.uuid))
        return
      }

      logger.warn(`Cannot mux files of video ${video.url}`, { err, inputs: inputsToLog, ...lTags(video.uuid) })

      throw err
    }

  } finally {
    for (const destination of tmpDestinations) {
      await remove(destination)
    }
  }
}

async function buildMuxInput (
  video: MVideo,
  videoFile: MVideoFile
): Promise<{ input: Readable, isTmpDestination: false } | { input: string, isTmpDestination: boolean }> {

  // ---------------------------------------------------------------------------
  // Remote
  // ---------------------------------------------------------------------------

  if (video.remote === true) {
    const timeout = REQUEST_TIMEOUTS.VIDEO_FILE

    const videoSizeKB = videoFile.size / 1000
    const bodyKBLimit = videoSizeKB + 0.1 * videoSizeKB

    // FFmpeg doesn't support multiple input streams, so download the audio file on disk directly
    if (videoFile.isAudio()) {
      const destination = VideoPathManager.Instance.buildTMPDestination(videoFile.filename)

      // > 1GB
      if (bodyKBLimit > 1000 * 1000) {
        throw new Error('Cannot download remote video file > 1GB')
      }

      await doRequestAndSaveToFile(videoFile.fileUrl, destination, { timeout, bodyKBLimit })

      return { input: destination, isTmpDestination: true }
    }

    return { input: generateRequestStream(videoFile.fileUrl, { timeout, bodyKBLimit }), isTmpDestination: false }
  }

  // ---------------------------------------------------------------------------
  // Local on FS
  // ---------------------------------------------------------------------------

  if (videoFile.storage === FileStorage.FILE_SYSTEM) {
    return { input: VideoPathManager.Instance.getFSVideoFileOutputPath(video, videoFile), isTmpDestination: false }
  }

  // ---------------------------------------------------------------------------
  // Local on object storage
  // ---------------------------------------------------------------------------

  // FFmpeg doesn't support multiple input streams, so download the audio file on disk directly
  if (videoFile.hasAudio() && !videoFile.hasVideo()) {
    const destination = VideoPathManager.Instance.buildTMPDestination(videoFile.filename)

    if (videoFile.isHLS()) {
      await makeHLSFileAvailable(video.getHLSPlaylist(), videoFile.filename, destination)
    } else {
      await makeWebVideoFileAvailable(videoFile.filename, destination)
    }

    return { input: destination, isTmpDestination: true }
  }

  if (videoFile.isHLS()) {
    const { stream } = await getHLSFileReadStream({
      playlist: video.getHLSPlaylist().withVideo(video),
      filename: videoFile.filename,
      rangeHeader: undefined
    })

    return { input: stream, isTmpDestination: false }
  }

  // Web video
  const { stream } = await getWebVideoFileReadStream({
    filename: videoFile.filename,
    rangeHeader: undefined
  })

  return { input: stream, isTmpDestination: false }
}

async function buildCoverInput (video: MVideoThumbnail) {
  const preview = video.getPreview()

  if (video.isOwned()) return { coverPath: preview?.getPath() }

  if (preview.fileUrl) {
    const destination = VideoPathManager.Instance.buildTMPDestination(preview.filename)

    await doRequestAndSaveToFile(preview.fileUrl, destination)

    return { coverPath: destination, isTmpDestination: true }
  }

  return { coverPath: undefined }
}