import { AssetEntity, AssetType, TranscodeHWAccel, TranscodePolicy, VideoCodec } from '@app/infra/entities';
import { Inject, Injectable, Logger, UnsupportedMediaTypeException } from '@nestjs/common';
import { join } from 'path';
import { IAssetRepository, WithoutProperty } from '../asset';
import { usePagination } from '../domain.util';
import { IBaseJob, IEntityJob, IJobRepository, JobName, JOBS_ASSET_PAGINATION_SIZE } from '../job';
import { IStorageRepository, StorageCore, StorageFolder } from '../storage';
import { ISystemConfigRepository, SystemConfigFFmpegDto } from '../system-config';
import { SystemConfigCore } from '../system-config/system-config.core';
import { AudioStreamInfo, IMediaRepository, VideoCodecHWConfig, VideoStreamInfo } from './media.repository';
import { H264Config, HEVCConfig, NVENCConfig, QSVConfig, ThumbnailConfig, VAAPIConfig, VP9Config } from './media.util';

@Injectable()
export class MediaService {
  private logger = new Logger(MediaService.name);
  private storageCore = new StorageCore();
  private configCore: SystemConfigCore;

  constructor(
    @Inject(IAssetRepository) private assetRepository: IAssetRepository,
    @Inject(IJobRepository) private jobRepository: IJobRepository,
    @Inject(IMediaRepository) private mediaRepository: IMediaRepository,
    @Inject(IStorageRepository) private storageRepository: IStorageRepository,
    @Inject(ISystemConfigRepository) systemConfig: ISystemConfigRepository,
  ) {
    this.configCore = new SystemConfigCore(systemConfig);
  }

  async handleQueueGenerateThumbnails(job: IBaseJob) {
    const { force } = job;

    const assetPagination = usePagination(JOBS_ASSET_PAGINATION_SIZE, (pagination) => {
      return force
        ? this.assetRepository.getAll(pagination)
        : this.assetRepository.getWithout(pagination, WithoutProperty.THUMBNAIL);
    });

    for await (const assets of assetPagination) {
      for (const asset of assets) {
        if (!asset.resizePath || force) {
          await this.jobRepository.queue({ name: JobName.GENERATE_JPEG_THUMBNAIL, data: { id: asset.id } });
          continue;
        }
        if (!asset.webpPath) {
          await this.jobRepository.queue({ name: JobName.GENERATE_WEBP_THUMBNAIL, data: { id: asset.id } });
        }
        if (!asset.thumbhash) {
          await this.jobRepository.queue({ name: JobName.GENERATE_THUMBHASH_THUMBNAIL, data: { id: asset.id } });
        }
      }
    }

    return true;
  }

  async handleGenerateJpegThumbnail({ id }: IEntityJob) {
    const [asset] = await this.assetRepository.getByIds([id]);
    if (!asset) {
      return false;
    }

    const resizePath = this.storageCore.getFolderLocation(StorageFolder.THUMBNAILS, asset.ownerId);
    this.storageRepository.mkdirSync(resizePath);
    const jpegThumbnailPath = join(resizePath, `${asset.id}.jpeg`);
    const { thumbnail } = await this.configCore.getConfig();

    switch (asset.type) {
      case AssetType.IMAGE:
        await this.mediaRepository.resize(asset.originalPath, jpegThumbnailPath, {
          size: thumbnail.jpegSize,
          format: 'jpeg',
        });
        this.logger.log(`Successfully generated image thumbnail ${asset.id}`);
        break;
      case AssetType.VIDEO:
        const { videoStreams } = await this.mediaRepository.probe(asset.originalPath);
        const mainVideoStream = this.getMainVideoStream(videoStreams);
        if (!mainVideoStream) {
          this.logger.error(`Could not extract thumbnail for asset ${asset.id}: no video streams found`);
          return false;
        }
        const { ffmpeg } = await this.configCore.getConfig();
        const config = { ...ffmpeg, targetResolution: thumbnail.jpegSize.toString(), twoPass: false };
        const options = new ThumbnailConfig(config).getOptions(mainVideoStream);
        await this.mediaRepository.transcode(asset.originalPath, jpegThumbnailPath, options);
        this.logger.log(`Successfully generated video thumbnail ${asset.id}`);
        break;
    }

    await this.assetRepository.save({ id: asset.id, resizePath: jpegThumbnailPath });

    return true;
  }

  async handleGenerateWebpThumbnail({ id }: IEntityJob) {
    const [asset] = await this.assetRepository.getByIds([id]);
    if (!asset || !asset.resizePath) {
      return false;
    }

    const webpPath = asset.resizePath.replace('jpeg', 'webp').replace('jpg', 'webp');

    const { thumbnail } = await this.configCore.getConfig();
    await this.mediaRepository.resize(asset.resizePath, webpPath, { size: thumbnail.webpSize, format: 'webp' });
    await this.assetRepository.save({ id: asset.id, webpPath });

    return true;
  }

  async handleGenerateThumbhashThumbnail({ id }: IEntityJob): Promise<boolean> {
    const [asset] = await this.assetRepository.getByIds([id]);
    if (!asset?.resizePath) {
      return false;
    }

    const thumbhash = await this.mediaRepository.generateThumbhash(asset.resizePath);
    await this.assetRepository.save({ id: asset.id, thumbhash });

    return true;
  }

  async handleQueueVideoConversion(job: IBaseJob) {
    const { force } = job;

    const assetPagination = usePagination(JOBS_ASSET_PAGINATION_SIZE, (pagination) => {
      return force
        ? this.assetRepository.getAll(pagination, { type: AssetType.VIDEO })
        : this.assetRepository.getWithout(pagination, WithoutProperty.ENCODED_VIDEO);
    });

    for await (const assets of assetPagination) {
      for (const asset of assets) {
        await this.jobRepository.queue({ name: JobName.VIDEO_CONVERSION, data: { id: asset.id } });
      }
    }

    return true;
  }

  async handleVideoConversion({ id }: IEntityJob) {
    const [asset] = await this.assetRepository.getByIds([id]);
    if (!asset || asset.type !== AssetType.VIDEO) {
      return false;
    }

    const input = asset.originalPath;
    const outputFolder = this.storageCore.getFolderLocation(StorageFolder.ENCODED_VIDEO, asset.ownerId);
    const output = join(outputFolder, `${asset.id}.mp4`);
    this.storageRepository.mkdirSync(outputFolder);

    const { videoStreams, audioStreams, format } = await this.mediaRepository.probe(input);
    const mainVideoStream = this.getMainVideoStream(videoStreams);
    const mainAudioStream = this.getMainAudioStream(audioStreams);
    const containerExtension = format.formatName;
    if (!mainVideoStream || !containerExtension) {
      return false;
    }

    const { ffmpeg: config } = await this.configCore.getConfig();

    const required = this.isTranscodeRequired(asset, mainVideoStream, mainAudioStream, containerExtension, config);
    if (!required) {
      return false;
    }

    let transcodeOptions;
    try {
      transcodeOptions = await this.getCodecConfig(config).then((c) => c.getOptions(mainVideoStream));
    } catch (err) {
      this.logger.error(`An error occurred while configuring transcoding options: ${err}`);
      return false;
    }

    this.logger.log(`Start encoding video ${asset.id} ${JSON.stringify(transcodeOptions)}`);
    try {
      await this.mediaRepository.transcode(input, output, transcodeOptions);
    } catch (err) {
      this.logger.error(err);
      if (config.accel && config.accel !== TranscodeHWAccel.DISABLED) {
        this.logger.error(
          `Error occurred during transcoding. Retrying with ${config.accel.toUpperCase()} acceleration disabled.`,
        );
      }
      config.accel = TranscodeHWAccel.DISABLED;
      transcodeOptions = await this.getCodecConfig(config).then((c) => c.getOptions(mainVideoStream));
      await this.mediaRepository.transcode(input, output, transcodeOptions);
    }

    this.logger.log(`Encoding success ${asset.id}`);

    await this.assetRepository.save({ id: asset.id, encodedVideoPath: output });

    return true;
  }

  private getMainVideoStream(streams: VideoStreamInfo[]): VideoStreamInfo | null {
    return streams.sort((stream1, stream2) => stream2.frameCount - stream1.frameCount)[0];
  }

  private getMainAudioStream(streams: AudioStreamInfo[]): AudioStreamInfo | null {
    return streams[0];
  }

  private isTranscodeRequired(
    asset: AssetEntity,
    videoStream: VideoStreamInfo,
    audioStream: AudioStreamInfo | null,
    containerExtension: string,
    ffmpegConfig: SystemConfigFFmpegDto,
  ): boolean {
    if (!videoStream.height || !videoStream.width) {
      this.logger.error('Skipping transcode, height or width undefined for video stream');
      return false;
    }

    const isTargetVideoCodec = videoStream.codecName === ffmpegConfig.targetVideoCodec;
    const isTargetContainer = ['mov,mp4,m4a,3gp,3g2,mj2', 'mp4', 'mov'].includes(containerExtension);
    const isTargetAudioCodec = audioStream == null || audioStream.codecName === ffmpegConfig.targetAudioCodec;

    this.logger.verbose(
      `${asset.id}: AudioCodecName ${audioStream?.codecName ?? 'None'}, AudioStreamCodecType ${
        audioStream?.codecType ?? 'None'
      }, containerExtension ${containerExtension}`,
    );

    const allTargetsMatching = isTargetVideoCodec && isTargetAudioCodec && isTargetContainer;
    const scalingEnabled = ffmpegConfig.targetResolution !== 'original';
    const targetRes = Number.parseInt(ffmpegConfig.targetResolution);
    const isLargerThanTargetRes = scalingEnabled && Math.min(videoStream.height, videoStream.width) > targetRes;

    switch (ffmpegConfig.transcode) {
      case TranscodePolicy.DISABLED:
        return false;

      case TranscodePolicy.ALL:
        return true;

      case TranscodePolicy.REQUIRED:
        return !allTargetsMatching || videoStream.isHDR;

      case TranscodePolicy.OPTIMAL:
        return !allTargetsMatching || isLargerThanTargetRes || videoStream.isHDR;

      default:
        return false;
    }
  }

  async getCodecConfig(config: SystemConfigFFmpegDto) {
    if (config.accel === TranscodeHWAccel.DISABLED) {
      return this.getSWCodecConfig(config);
    }
    return this.getHWCodecConfig(config);
  }

  private getSWCodecConfig(config: SystemConfigFFmpegDto) {
    switch (config.targetVideoCodec) {
      case VideoCodec.H264:
        return new H264Config(config);
      case VideoCodec.HEVC:
        return new HEVCConfig(config);
      case VideoCodec.VP9:
        return new VP9Config(config);
      default:
        throw new UnsupportedMediaTypeException(`Codec '${config.targetVideoCodec}' is unsupported`);
    }
  }

  private async getHWCodecConfig(config: SystemConfigFFmpegDto) {
    let handler: VideoCodecHWConfig;
    let devices: string[];
    switch (config.accel) {
      case TranscodeHWAccel.NVENC:
        handler = new NVENCConfig(config);
        break;
      case TranscodeHWAccel.QSV:
        devices = await this.storageRepository.readdir('/dev/dri');
        handler = new QSVConfig(config, devices);
        break;
      case TranscodeHWAccel.VAAPI:
        devices = await this.storageRepository.readdir('/dev/dri');
        handler = new VAAPIConfig(config, devices);
        break;
      default:
        throw new UnsupportedMediaTypeException(`${config.accel.toUpperCase()} acceleration is unsupported`);
    }
    if (!handler.getSupportedCodecs().includes(config.targetVideoCodec)) {
      throw new UnsupportedMediaTypeException(
        `${config.accel.toUpperCase()} acceleration does not support codec '${config.targetVideoCodec.toUpperCase()}'. Supported codecs: ${handler.getSupportedCodecs()}`,
      );
    }

    return handler;
  }
}