import {Logger} from '../../Logger';
import {FfmpegCommand} from 'fluent-ffmpeg';
import {FFmpegFactory} from '../FFmpegFactory';


export interface VideoConverterInput {
  videoPath: string;
  output: {
    path: string,
    bitRate?: number,
    resolution?: 240 | 360 | 480 | 720 | 1080 | 1440 | 2160 | 4320,
    fps?: number,
    codec: string,
    format: string
  };
}

export class VideoConverterWorker {

  private static ffmpeg = FFmpegFactory.get();

  public static convert(input: VideoConverterInput): Promise<void> {

    if (this.ffmpeg == null) {
      this.ffmpeg = FFmpegFactory.get();
    }

    return new Promise((resolve, reject) => {

      Logger.silly('[FFmpeg] transcoding video: ' + input.videoPath);


      const command: FfmpegCommand = this.ffmpeg(input.videoPath);
      let executedCmd = '';
      command
        .on('start', (cmd: string) => {
          Logger.silly('[FFmpeg] running:' + cmd);
          executedCmd = cmd;
        })
        .on('end', () => {
          resolve();
        })
        .on('error', (e: any) => {
          reject('[FFmpeg] ' + e.toString() + ' executed: ' + executedCmd);
        });
      // set video bitrate
      if (input.output.bitRate) {
        command.videoBitrate((input.output.bitRate / 1024) + 'k');
      }
      // set target codec
      command.videoCodec(input.output.codec);
      if (input.output.resolution) {
        command.size('?x' + input.output.resolution);
      }

      // set fps
      if (input.output.fps) {
        command.fps(input.output.fps);
      }
      // set output format to force
      command.format(input.output.format)
        // save to file
        .save(input.output.path);

    });
  }

}