AudioRecorderManager.m

//
//  AudioRecorderManager.m
//  AudioRecorderManager
//
//  Created by Joshua Sierles on 15/04/15.
//  Copyright (c) 2015 Joshua Sierles. All rights reserved.
//

#import "AudioRecorderManager.h"
#import "RCTConvert.h"
#import "RCTBridge.h"
#import "RCTEventDispatcher.h"
#import <AVFoundation/AVFoundation.h>

NSString *const AudioRecorderEventProgress = @"recordingProgress";
NSString *const AudioRecorderEventFinished = @"recordingFinished";

@implementation AudioRecorderManager {
  
  AVAudioRecorder *_audioRecorder;
  AVAudioPlayer *_audioPlayer;

  NSTimeInterval _currentTime;
  id _progressUpdateTimer;
  int _progressUpdateInterval;
  NSDate *_prevProgressUpdateTime;
  NSURL *_audioFileURL;
  AVAudioSession *_recordSession;
}

@synthesize bridge = _bridge;

RCT_EXPORT_MODULE();

- (void)sendProgressUpdate {
  if (_audioRecorder && _audioRecorder.recording) {
    _currentTime = _audioRecorder.currentTime;
  } else if (_audioPlayer && _audioPlayer.playing) {
    _currentTime = _audioPlayer.currentTime;
  } else {
    return;
  }
  NSString *time = [NSString stringWithFormat:@"%f", _currentTime];

  if (_prevProgressUpdateTime == nil ||
   (([_prevProgressUpdateTime timeIntervalSinceNow] * -1000.0) >= _progressUpdateInterval)) {
      [_bridge.eventDispatcher sendDeviceEventWithName:AudioRecorderEventProgress body:@{
      @"currentTime": [NSNumber numberWithFloat:_currentTime]
    }];

    _prevProgressUpdateTime = [NSDate date];
  }
}

- (void)stopProgressTimer {
  [_progressUpdateTimer invalidate];
}

- (void)startProgressTimer {
  _progressUpdateInterval = 250;
  _prevProgressUpdateTime = nil;

  [self stopProgressTimer];

  _progressUpdateTimer = [CADisplayLink displayLinkWithTarget:self selector:@selector(sendProgressUpdate)];
  [_progressUpdateTimer addToRunLoop:[NSRunLoop mainRunLoop] forMode:NSDefaultRunLoopMode];
}

- (void)audioRecorderDidFinishRecording:(AVAudioRecorder *)recorder successfully:(BOOL)flag {
  NSLog(flag ? @"FINISHED OK" : @"FINISH ERROR");
  [_bridge.eventDispatcher sendDeviceEventWithName:AudioRecorderEventFinished body:@{
      @"finished": @"test"
    }];
}

RCT_EXPORT_METHOD(prepareRecordingAtPath:(NSString *)path)
{

  _prevProgressUpdateTime = nil;
  [self stopProgressTimer];

  NSString *resourcePath = [[NSBundle mainBundle] resourcePath];
  NSString *audioFilePath = [resourcePath stringByAppendingPathComponent:path];

  _audioFileURL = [NSURL fileURLWithPath:audioFilePath];

  NSDictionary *recordSettings = [NSDictionary dictionaryWithObjectsAndKeys:
          [NSNumber numberWithInt:AVAudioQualityHigh], AVEncoderAudioQualityKey,
          [NSNumber numberWithInt:16], AVEncoderBitRateKey,
          [NSNumber numberWithInt: 2], AVNumberOfChannelsKey,
          [NSNumber numberWithFloat:44100.0], AVSampleRateKey,
          nil];

  NSError *error = nil;

  _recordSession = [AVAudioSession sharedInstance];
  [_recordSession setCategory:AVAudioSessionCategoryPlayAndRecord error:nil];

  _audioRecorder = [[AVAudioRecorder alloc]
                initWithURL:_audioFileURL
                settings:recordSettings
                error:&error];
  
  _audioRecorder.delegate = self;

  if (error) {
      NSLog(@"error: %@", [error localizedDescription]);
      // TODO: dispatch error over the bridge
    } else {
      [_audioRecorder prepareToRecord];
  }
}

RCT_EXPORT_METHOD(startRecording)
{
  if (!_audioRecorder.recording) {
    [self startProgressTimer];
    [_recordSession setActive:YES error:nil];
    [_audioRecorder record];

  }
}

RCT_EXPORT_METHOD(stopRecording)
{
  if (_audioRecorder.recording) {
    [_audioRecorder stop];
    [_recordSession setActive:NO error:nil];
    _prevProgressUpdateTime = nil;
  }
}

RCT_EXPORT_METHOD(pauseRecording)
{
  if (_audioRecorder.recording) {
    [self stopProgressTimer];
    [_audioRecorder pause];
  }
}

RCT_EXPORT_METHOD(playRecording)
{
  if (_audioRecorder.recording) {
    NSLog(@"stop the recording before playing");
    return;

  } else {

    NSError *error;

    if (!_audioPlayer.playing) {
      _audioPlayer = [[AVAudioPlayer alloc]
        initWithContentsOfURL:_audioRecorder.url
        error:&error];

      if (error) {
        [self stopProgressTimer];
        NSLog(@"audio playback loading error: %@", [error localizedDescription]);
        // TODO: dispatch error over the bridge
      } else {
        [self startProgressTimer];
        [_audioPlayer play];
      }
    }
  }
}

RCT_EXPORT_METHOD(pausePlaying)
{
  if (_audioPlayer.playing) {
    [_audioPlayer pause];
  }
}

RCT_EXPORT_METHOD(stopPlaying)
{
  if (_audioPlayer.playing) {
    [_audioPlayer stop];
  }
}

@end