import 'dart:async';
import 'dart:ffi' as ffi;
import 'dart:io';
import 'dart:typed_data';

import 'package:ffmpeg_kit_flutter/ffmpeg_kit.dart';
import 'package:ffmpeg_kit_flutter/return_code.dart';
import 'package:flutter/services.dart';
import 'package:path_provider/path_provider.dart';

class G711 {
  Future<List<int>> readAssetFile(String assetPath) async {
    ByteData data = await rootBundle.load(assetPath);
    List<int> bytes = data.buffer.asUint8List();
    return bytes;
  }

  int ALawToLinear(int aVal) {
    // 取反
    aVal = ~aVal;

    // 计算偏移
    int t = ((aVal & 0x0F) << 3) + 0x84;
    t <<= (aVal & 0x70) >> 4;

    // 根据符号位决定返回值的正负
    return (aVal & 0x80) != 0 ? 0x84 - t : t - 0x84;
  }

  List<int> convertList(List<int> aLawList) {
    // 将 ALawToLinear 函数应用于 List<int>
    List<int> linearList = aLawList.map(ALawToLinear).toList();
    return linearList;
  }

  Future<Uint8List?> decodeG711ToPCM(List<int> g711Data) async {
    // FlutterFFmpeg flutterFFmpeg = FlutterFFmpeg();

    // Save G.711 data to a temporary file
    Directory appDocDir = await getApplicationDocumentsDirectory();
    String g711FilePath = '${appDocDir.path}/input.g711';
    await File(g711FilePath).writeAsBytes(g711Data);

    // Replace with the desired output PCM file path
    String pcmFilePath = '${appDocDir.path}/output.pcm';

    // Run FFmpeg command to decode G.711 to PCM
    // String command =
    //     '-y -f u8 -ar 8000 -ac 1 -i $g711FilePath -f s16le -ar 8000 -ac 1 $pcmFilePath';
    try {
      final session = await FFmpegKit.execute(
        '-y -f u8 -ar 8000 -ac 1 -i $g711FilePath -f s16le -ar 8000 -ac 1 $pcmFilePath',
      );

      final returnCode = await session.getReturnCode();

      if (ReturnCode.isSuccess(returnCode)) {
        Uint8List pcmBytes = await File(pcmFilePath).readAsBytes();
        return pcmBytes;
      } else {
        print('FFmpeg execution failed with rc=$returnCode');
        // 处理执行失败的情况
      }
    } catch (e) {
      print('Error executing FFmpeg command: $e');
      // 处理异常情况
    }
    return null;
  }

  // Future<Uint8List?> encodePCMToG711(Uint8List pcmData) async {
  //   try {
  //     // FlutterFFmpeg flutterFFmpeg = FlutterFFmpeg();

  //     // Save PCM data to a temporary file
  //     Directory appDocDir = await getApplicationDocumentsDirectory();
  //     String pcmFilePath = '${appDocDir.path}/input.pcm';
  //     await File(pcmFilePath).writeAsBytes(pcmData);

  //     // Replace with the desired output G.711 file path
  //     String g711FilePath = '${appDocDir.path}/output.g711';

  //     // Run FFmpeg command to encode PCM to G.711
  //     String command =
  //         '-y -f s16le -ar 8000 -ac 1 -i $pcmFilePath -f g711 -ar 8000 -ac 1 $g711FilePath';
  //     int result = await flutterFFmpeg.execute(command);

  //     if (result == 0) {
  //       print(
  //           'PCM encoding to G.711 successful! G.711 file saved at: $g711FilePath');

  //       // Read G.711 data from file
  //       Uint8List g711Bytes = await File(g711FilePath).readAsBytes();

  //       // Delete the temporary PCM file
  //       await File(pcmFilePath).delete();

  //       // Delete the temporary G.711 file
  //       await File(g711FilePath).delete();

  //       return g711Bytes;
  //     } else {
  //       print('Error during PCM encoding to G.711: $result');
  //       return null;
  //     }
  //   } catch (e) {
  //     print('Error: $e');
  //     return null;
  //   }
  // }
}