//
// AudioController.m
// AudioCapture
//
// Created by CavanSu on 10/11/2017.
// Copyright © 2017 Agora. All rights reserved.
//

#import "AudioController.h"
#import "AudioWriteToFile.h"

#define InputBus 1
#define OutputBus 0

@interface AudioController ()
@property (nonatomic, assign) int sampleRate;
@property (nonatomic, assign) int channelCount;
@property (nonatomic, assign) AudioCRMode audioCRMode;
@property (nonatomic, assign) OSStatus error;

@property (nonatomic, assign) AudioUnit remoteIOUnit;
#if TARGET_OS_MAC
@property (nonatomic, assign) AudioUnit macPlayUnit;
#endif
@end

@implementation AudioController

#if TARGET_OS_IPHONE
static double preferredIOBufferDuration = 0.02;
#endif

+ (instancetype)audioController {
 AudioController *audioController = [[self alloc] init];
 return audioController;
}

#pragma mark - <Capture Call Back>
static OSStatus captureCallBack(void *inRefCon,
 AudioUnitRenderActionFlags *ioActionFlags,
 const AudioTimeStamp *inTimeStamp,
 UInt32 inBusNumber, // inputBus = 1
 UInt32 inNumberFrames,
 AudioBufferList *ioData)
{
 AudioController *audioController = (__bridge AudioController *)inRefCon;
 
 AudioUnit captureUnit = [audioController remoteIOUnit];
 
 if (!inRefCon) return 0;
 
 AudioBuffer buffer;
 buffer.mData = NULL;
 buffer.mDataByteSize = 0;
 buffer.mNumberChannels = audioController.channelCount;
 
 AudioBufferList bufferList;
 bufferList.mNumberBuffers = 1;
 bufferList.mBuffers[0] = buffer;
 
 OSStatus status = AudioUnitRender(captureUnit,
 ioActionFlags,
 inTimeStamp,
 inBusNumber,
 inNumberFrames,
 &bufferList);
 
 if (!status) {
 if ([audioController.delegate respondsToSelector:@selector(audioController:didCaptureData:bytesLength:)]) {
 [audioController.delegate audioController:audioController didCaptureData:(unsigned char *)bufferList.mBuffers[0].mData bytesLength:bufferList.mBuffers[0].mDataByteSize];
 }
 }
 else {
 [audioController error:status position:@"captureCallBack"];
 }
 
 return 0;
}

#pragma mark - <Render Call Back>
static OSStatus renderCallBack(void *inRefCon,
 AudioUnitRenderActionFlags *ioActionFlags,
 const AudioTimeStamp *inTimeStamp,
 UInt32 inBusNumber,
 UInt32 inNumberFrames,
 AudioBufferList *ioData)
{
 AudioController *audioController = (__bridge AudioController *)(inRefCon);
 
 if (*ioActionFlags == kAudioUnitRenderAction_OutputIsSilence) {
 return noErr;
 }
 
 int result = 0;

 if ([audioController.delegate respondsToSelector:@selector(audioController:didRenderData:bytesLength:)]) {
 result = [audioController.delegate audioController:audioController didRenderData:(uint8_t*)ioData->mBuffers[0].mData bytesLength:ioData->mBuffers[0].mDataByteSize];
 }
 
 if (result == 0) {
 *ioActionFlags = kAudioUnitRenderAction_OutputIsSilence;
 ioData->mBuffers[0].mDataByteSize = 0;
 }

 return noErr;
}


#pragma mark - <Step 1, Set Up Audio Session>
- (void)setUpAudioSessionWithSampleRate:(int)sampleRate channelCount:(int)channelCount audioCRMode:(AudioCRMode)audioCRMode IOType:(IOUnitType)ioType{
 if (_audioCRMode == AudioCRModeSDKCaptureSDKRender) {
 return;
 }
 
 self.audioCRMode = audioCRMode;
 self.sampleRate = sampleRate;
 self.channelCount = channelCount;
 
#if TARGET_OS_IPHONE
 AVAudioSession *audioSession = [AVAudioSession sharedInstance];
 NSUInteger sessionOption = AVAudioSessionCategoryOptionMixWithOthers;
 sessionOption |= AVAudioSessionCategoryOptionAllowBluetooth;
 
 [audioSession setCategory:AVAudioSessionCategoryPlayAndRecord withOptions:sessionOption error:nil];
 [audioSession setMode:AVAudioSessionModeDefault error:nil];
 [audioSession setPreferredIOBufferDuration:preferredIOBufferDuration error:nil];
 NSError *error;
 BOOL success = [audioSession setActive:YES error:&error];
 if (!success) {
 NSLog(@"<Error> audioSession setActive:YES error:nil");
 }
 if (error) {
 NSLog(@"<Error> setUpAudioSessionWithSampleRate : %@", error.localizedDescription);
 }
#endif
 
 [self setupRemoteIOWithIOType:ioType];
}

#pragma mark - <Step 2, Set Up Audio Unit>
- (void)setupRemoteIOWithIOType:(IOUnitType)ioType {
#if TARGET_OS_IPHONE
 // AudioComponentDescription
 AudioComponentDescription remoteIODesc;
 remoteIODesc.componentType = kAudioUnitType_Output;
 remoteIODesc.componentSubType = ioType == IOUnitTypeVPIO ? kAudioUnitSubType_VoiceProcessingIO : kAudioUnitSubType_RemoteIO;
 remoteIODesc.componentManufacturer = kAudioUnitManufacturer_Apple;
 remoteIODesc.componentFlags = 0;
 remoteIODesc.componentFlagsMask = 0;
 AudioComponent remoteIOComponent = AudioComponentFindNext(NULL, &remoteIODesc);
 _error = AudioComponentInstanceNew(remoteIOComponent, &_remoteIOUnit);
 [self error:_error position:@"AudioComponentInstanceNew"];
#endif
 
 if (_audioCRMode == AudioCRModeExterCaptureSDKRender || _audioCRMode == AudioCRModeExterCaptureExterRender) {
 
#if !TARGET_OS_IPHONE
 AudioComponentDescription remoteIODesc;
 remoteIODesc.componentType = kAudioUnitType_Output;
 remoteIODesc.componentSubType = kAudioUnitSubType_HALOutput;
 remoteIODesc.componentManufacturer = kAudioUnitManufacturer_Apple;
 remoteIODesc.componentFlags = 0;
 remoteIODesc.componentFlagsMask = 0;
 AudioComponent remoteIOComponent = AudioComponentFindNext(NULL, &remoteIODesc);
 _error = AudioComponentInstanceNew(remoteIOComponent, &_remoteIOUnit);
 [self error:_error position:@"AudioComponentInstanceNew"];
 _error = AudioUnitInitialize(_remoteIOUnit);
 [self error:_error position:@"AudioUnitInitialize"];
#endif
 [self setupCapture];
 }
 
 if (_audioCRMode == AudioCRModeSDKCaptureExterRender || _audioCRMode == AudioCRModeExterCaptureExterRender) {
 
#if !TARGET_OS_IPHONE
 AudioComponentDescription macPlayDesc;
 macPlayDesc.componentType = kAudioUnitType_Output;
 macPlayDesc.componentSubType = kAudioUnitSubType_DefaultOutput;
 macPlayDesc.componentManufacturer = kAudioUnitManufacturer_Apple;
 macPlayDesc.componentFlags = 0;
 macPlayDesc.componentFlagsMask = 0;
 AudioComponent macPlayComponent = AudioComponentFindNext(NULL, &macPlayDesc);
 _error = AudioComponentInstanceNew(macPlayComponent, &_macPlayUnit);
 [self error:_error position:@"AudioComponentInstanceNew"];
 _error = AudioUnitInitialize(_macPlayUnit);
 [self error:_error position:@"AudioUnitInitialize"];
#endif
 [self setupRender];
 }

}

- (void)setupCapture {
 // EnableIO
 UInt32 one = 1;
 _error = AudioUnitSetProperty(_remoteIOUnit,
 kAudioOutputUnitProperty_EnableIO,
 kAudioUnitScope_Input,
 InputBus,
 &one,
 sizeof(one));
 [self error:_error position:@"kAudioOutputUnitProperty_EnableIO, kAudioUnitScope_Input"];

#if !TARGET_OS_IPHONE
 UInt32 disableFlag = 0;
 
 // Attention! set kAudioOutputUnitProperty_EnableIO, kAudioUnitScope_Output, disable
 _error = AudioUnitSetProperty(_remoteIOUnit,
 kAudioOutputUnitProperty_EnableIO,
 kAudioUnitScope_Output,
 OutputBus,
 &disableFlag,
 sizeof(disableFlag));
 [self error:_error position:@"kAudioOutputUnitProperty_EnableIO, kAudioUnitScope_Output"];
 
 AudioDeviceID defaultDevice = kAudioDeviceUnknown;
 UInt32 propertySize = sizeof(defaultDevice);
 AudioObjectPropertyAddress defaultDeviceProperty = {
 .mSelector = kAudioHardwarePropertyDefaultInputDevice,
 .mScope = kAudioObjectPropertyScopeInput,
 .mElement = kAudioObjectPropertyElementMaster
 };
 
 _error = AudioObjectGetPropertyData(kAudioObjectSystemObject,
 &defaultDeviceProperty,
 0,
 NULL,
 &propertySize,
 &defaultDevice);
 [self error:_error position:@"AudioObjectGetPropertyData, kAudioObjectSystemObject"];
 
 // Set the sample rate of the input device to the output samplerate (if possible)
 Float64 temp = _sampleRate;
 defaultDeviceProperty.mSelector = kAudioDevicePropertyNominalSampleRate;
 
 _error = AudioObjectSetPropertyData(defaultDevice,
 &defaultDeviceProperty,
 0,
 NULL,
 sizeof(Float64),
 &temp);
 [self error:_error position:@"AudioObjectSetPropertyData, defaultDeviceProperty"];
 
 // Set the input device to the system's default input device
 _error = AudioUnitSetProperty(_remoteIOUnit,
 kAudioOutputUnitProperty_CurrentDevice,
 kAudioUnitScope_Global,
 InputBus,
 &defaultDevice,
 sizeof(defaultDevice));
 [self error:_error position:@"kAudioOutputUnitProperty_CurrentDevice, kAudioUnitScope_Global"];
 
#endif
 
 // AudioStreamBasicDescription
 AudioStreamBasicDescription streamFormatDesc = [self signedIntegerStreamFormatDesc];
 _error = AudioUnitSetProperty(_remoteIOUnit,
 kAudioUnitProperty_StreamFormat,
 kAudioUnitScope_Output,
 InputBus,
 &streamFormatDesc,
 sizeof(streamFormatDesc));
 [self error:_error position:@"kAudioUnitProperty_StreamFormat, kAudioUnitScope_Output"];
 
 // CallBack
 AURenderCallbackStruct captureCallBackStruck;
 captureCallBackStruck.inputProcRefCon = (__bridge void * _Nullable)(self);
 captureCallBackStruck.inputProc = captureCallBack;
 
 _error = AudioUnitSetProperty(_remoteIOUnit,
 kAudioOutputUnitProperty_SetInputCallback,
 kAudioUnitScope_Global,
 InputBus,
 &captureCallBackStruck,
 sizeof(captureCallBackStruck));
 [self error:_error position:@"kAudioOutputUnitProperty_SetInputCallback"];
}

- (void)setupRender {
 
#if TARGET_OS_IPHONE
 // EnableIO
 UInt32 one = 1;
 _error = AudioUnitSetProperty(_remoteIOUnit,
 kAudioOutputUnitProperty_EnableIO,
 kAudioUnitScope_Output,
 OutputBus,
 &one,
 sizeof(one));
 [self error:_error position:@"kAudioOutputUnitProperty_EnableIO, kAudioUnitScope_Output"];
 
 // AudioStreamBasicDescription
 AudioStreamBasicDescription streamFormatDesc = [self signedIntegerStreamFormatDesc];
 _error = AudioUnitSetProperty(_remoteIOUnit,
 kAudioUnitProperty_StreamFormat,
 kAudioUnitScope_Input,
 OutputBus,
 &streamFormatDesc,
 sizeof(streamFormatDesc));
 [self error:_error position:@"kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input"];
 
 // CallBack
 AURenderCallbackStruct renderCallback;
 renderCallback.inputProcRefCon = (__bridge void * _Nullable)(self);
 renderCallback.inputProc = renderCallBack;
 AudioUnitSetProperty(_remoteIOUnit,
 kAudioUnitProperty_SetRenderCallback,
 kAudioUnitScope_Input,
 OutputBus,
 &renderCallback,
 sizeof(renderCallback));
 [self error:_error position:@"kAudioUnitProperty_SetRenderCallback"];
 
#else

 // AudioStreamBasicDescription
 AudioStreamBasicDescription streamFormatDesc = [self signedIntegerStreamFormatDesc];
 _error = AudioUnitSetProperty(_macPlayUnit,
 kAudioUnitProperty_StreamFormat,
 kAudioUnitScope_Input,
 OutputBus,
 &streamFormatDesc,
 sizeof(streamFormatDesc));
 [self error:_error position:@"kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input"];
 
 // CallBack
 AURenderCallbackStruct renderCallback;
 renderCallback.inputProcRefCon = (__bridge void * _Nullable)(self);
 renderCallback.inputProc = renderCallBack;
 _error = AudioUnitSetProperty(_macPlayUnit,
 kAudioUnitProperty_SetRenderCallback,
 kAudioUnitScope_Input,
 OutputBus,
 &renderCallback,
 sizeof(renderCallback));
 [self error:_error position:@"kAudioUnitProperty_SetRenderCallback"];
#endif
 
}

- (void)startWork {
#if TARGET_OS_IPHONE
 _error = AudioOutputUnitStart(_remoteIOUnit);
 [self error:_error position:@"AudioOutputUnitStart"];
#else
 if (_audioCRMode == AudioCRModeExterCaptureSDKRender || _audioCRMode == AudioCRModeExterCaptureExterRender) {
 _error = AudioOutputUnitStart(_remoteIOUnit);
 if (_error != noErr) {
 [self error:_error position:@"AudioOutputUnitStart"];
 return;
 }
 }
 
 if (self.audioCRMode == AudioCRModeExterCaptureExterRender || self.audioCRMode == AudioCRModeSDKCaptureExterRender) {
 _error = AudioOutputUnitStart(_macPlayUnit);
 [self error:_error position:@"AudioOutputUnitStart"];
 }
#endif
}

- (void)stopWork {
#if TARGET_OS_IPHONE
 AudioOutputUnitStop(_remoteIOUnit);
#else
 if (_audioCRMode == AudioCRModeExterCaptureSDKRender || _audioCRMode == AudioCRModeExterCaptureExterRender) {
 AudioOutputUnitStop(_remoteIOUnit);
 }
 
 if (self.audioCRMode == AudioCRModeExterCaptureExterRender || self.audioCRMode == AudioCRModeSDKCaptureExterRender) {
 AudioOutputUnitStop(_macPlayUnit);
 }
#endif
}

- (void)error:(OSStatus)error position:(NSString *)position {
 if (error != noErr) {
 NSString *errorInfo = [NSString stringWithFormat:@"<ACLog> Error: %d, Position: %@", (int)error, position];
 if ([self.delegate respondsToSelector:@selector(audioController:error:info:)]) {
 [self.delegate audioController:self error:error info:position];
 }
 NSLog(@"<OSStatus> :%@", errorInfo);
 }
}

- (AudioStreamBasicDescription)signedIntegerStreamFormatDesc {
 AudioStreamBasicDescription streamFormatDesc;
 streamFormatDesc.mSampleRate = _sampleRate;
 streamFormatDesc.mFormatID = kAudioFormatLinearPCM;
 streamFormatDesc.mFormatFlags = (kAudioFormatFlagIsSignedInteger | kAudioFormatFlagsNativeEndian | kAudioFormatFlagIsPacked);
 streamFormatDesc.mChannelsPerFrame = _channelCount;
 streamFormatDesc.mFramesPerPacket = 1;
 streamFormatDesc.mBitsPerChannel = 16;
 streamFormatDesc.mBytesPerFrame = streamFormatDesc.mBitsPerChannel / 8 * streamFormatDesc.mChannelsPerFrame;
 streamFormatDesc.mBytesPerPacket = streamFormatDesc.mBytesPerFrame * streamFormatDesc.mFramesPerPacket;
 
 return streamFormatDesc;
}

- (void)dealloc {
 if (_remoteIOUnit) {
 AudioOutputUnitStop(_remoteIOUnit);
 AudioComponentInstanceDispose(_remoteIOUnit);
 _remoteIOUnit = nil;
 }
 
#if !TARGET_OS_IPHONE
 if (_macPlayUnit) {
 AudioOutputUnitStop(_macPlayUnit);
 AudioComponentInstanceDispose(_macPlayUnit);
 _macPlayUnit = nil;
 }
#endif
 
 NSLog(@"<ACLog> AudioController dealloc");
}

@end