import 'dart:io';
import 'package:flutter/services.dart';
import 'package:path_provider/path_provider.dart';
import 'package:flutter/foundation.dart';
import 'package:process_run/process_run.dart';

class ConverterService {
  late Directory tempDir;
  late String assetName;
  late String ffmpegPath;

  ConverterService._();

  static Future<ConverterService> init() async {
    debugPrint('Initializing DLServices');
    var dlService = ConverterService._();
    await dlService._init();
    return dlService;
  }

  Future<void> _init() async {
    tempDir = await getTemporaryDirectory();
    assetName = 'ffmpeg.exe';
    await copyExecutable();
  }

  Future<void> copyExecutable() async {
    File tempFile = File('${tempDir.path}/$assetName');

    ByteData data = await rootBundle.load('assets/executable/$assetName');
    await tempFile.exists().then((value) {
      if (!value) {
        debugPrint('Copying $assetName to ${tempFile.path}');
        tempFile.writeAsBytes(
            data.buffer.asUint8List(data.offsetInBytes, data.lengthInBytes));
      }
    });

    ffmpegPath = tempFile.path;
  }

  Future<Stream> convertFile(String inputPath, String outputPath) async {
    debugPrint('Converting $inputPath to $outputPath');

    var command = ' -q --flat-playlist -J';

    var shellLinesController = ShellLinesController();
    var shell = Shell(stdout: shellLinesController.sink);
    await shell.run('''
      $ffmpegPath $command
    ''').then((result) {
      debugPrint('Analyse result: ${result}');
    });

    return shellLinesController.stream;
  }
}