/*
*	File:		StereoFX.cpp
*	
*	Version:	1.0
* 
*	Created:	5/21/07
*	
*	Copyright:  Copyright © 2007 Airwindows, Airwindows uses the MIT license
* 
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/*=============================================================================
	StereoFX.h
	
=============================================================================*/
#include "StereoFX.h"


//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

COMPONENT_ENTRY(StereoFX)


//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	StereoFX::StereoFX
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
StereoFX::StereoFX(AudioUnit component)
	: AUEffectBase(component)
{
	CreateElements();
	Globals()->UseIndexedParameters(kNumberOfParameters);
	SetParameter(kParam_One, kDefaultValue_ParamOne );
	SetParameter(kParam_Two, kDefaultValue_ParamTwo );
	SetParameter(kParam_Three, kDefaultValue_ParamThree );
        
#if AU_DEBUG_DISPATCHER
	mDebugDispatcher = new AUDebugDispatcher (this);
#endif
	
}


//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	StereoFX::GetParameterValueStrings
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ComponentResult		StereoFX::GetParameterValueStrings(AudioUnitScope		inScope,
                                                                AudioUnitParameterID	inParameterID,
                                                                CFArrayRef *		outStrings)
{
        
    return kAudioUnitErr_InvalidProperty;
}



//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	StereoFX::GetParameterInfo
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ComponentResult		StereoFX::GetParameterInfo(AudioUnitScope		inScope,
                                                        AudioUnitParameterID	inParameterID,
                                                        AudioUnitParameterInfo	&outParameterInfo )
{
	ComponentResult result = noErr;

	outParameterInfo.flags = 	kAudioUnitParameterFlag_IsWritable
						|		kAudioUnitParameterFlag_IsReadable;
    
    if (inScope == kAudioUnitScope_Global) {
        switch(inParameterID)
        {
             case kParam_One:
                AUBase::FillInParameterName (outParameterInfo, kParameterOneName, false);
                outParameterInfo.unit = kAudioUnitParameterUnit_Generic;
                outParameterInfo.minValue = 0.0;
                outParameterInfo.maxValue = 1.0;
                outParameterInfo.defaultValue = kDefaultValue_ParamOne;
                break;
            case kParam_Two:
                AUBase::FillInParameterName (outParameterInfo, kParameterTwoName, false);
                outParameterInfo.unit = kAudioUnitParameterUnit_Generic;
                outParameterInfo.minValue = 0.0;
                outParameterInfo.maxValue = 1.0;
                outParameterInfo.defaultValue = kDefaultValue_ParamTwo;
                break;
			case kParam_Three:
                AUBase::FillInParameterName (outParameterInfo, kParameterThreeName, false);
                outParameterInfo.unit = kAudioUnitParameterUnit_Generic;
                outParameterInfo.minValue = 0.0;
                outParameterInfo.maxValue = 1.0;
                outParameterInfo.defaultValue = kDefaultValue_ParamThree;
                break;
            default:
                result = kAudioUnitErr_InvalidParameter;
                break;
            }
	} else {
        result = kAudioUnitErr_InvalidParameter;
    }
    


	return result;
}

//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	StereoFX::GetPropertyInfo
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ComponentResult		StereoFX::GetPropertyInfo (AudioUnitPropertyID	inID,
                                                        AudioUnitScope		inScope,
                                                        AudioUnitElement	inElement,
                                                        UInt32 &		outDataSize,
                                                        Boolean &		outWritable)
{
	return AUEffectBase::GetPropertyInfo (inID, inScope, inElement, outDataSize, outWritable);
}

//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// state that plugin supports only stereo-in/stereo-out processing
UInt32 StereoFX::SupportedNumChannels(const AUChannelInfo ** outInfo)
{
	if (outInfo != NULL)
	{
		static AUChannelInfo info;
		info.inChannels = 2;
		info.outChannels = 2;
		*outInfo = &info;
	}

	return 1;
}

//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	StereoFX::GetProperty
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ComponentResult		StereoFX::GetProperty(	AudioUnitPropertyID inID,
                                                        AudioUnitScope 		inScope,
                                                        AudioUnitElement 	inElement,
                                                        void *			outData )
{
	return AUEffectBase::GetProperty (inID, inScope, inElement, outData);
}

//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	StereoFX::Initialize
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ComponentResult StereoFX::Initialize()
{
    ComponentResult result = AUEffectBase::Initialize();
    if (result == noErr)
        Reset(kAudioUnitScope_Global, 0);
    return result;
}

#pragma mark ____StereoFXEffectKernel

//-----------------------------------------------------------------------------------------
// this is called the reset the DSP state (clear buffers, reset counters, etc.)
ComponentResult		StereoFX::Reset(AudioUnitScope inScope, AudioUnitElement inElement)
{
	iirSampleA = 0.0;
	iirSampleB = 0.0;
	flip = false;
	fpdL = 1.0; while (fpdL < 16386) fpdL = rand()*UINT32_MAX;
	fpdR = 1.0; while (fpdR < 16386) fpdR = rand()*UINT32_MAX;
	return noErr;
}


//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	StereoFX::ProcessBufferLists
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
OSStatus		StereoFX::ProcessBufferLists(AudioUnitRenderActionFlags & ioActionFlags,
													const AudioBufferList & inBuffer,
                                                    AudioBufferList & outBuffer,
                                                    UInt32 			inFramesToProcess)
{

	Float32 * inputL = (Float32*)(inBuffer.mBuffers[0].mData);
	Float32 * inputR = (Float32*)(inBuffer.mBuffers[1].mData);
	Float32 * outputL = (Float32*)(outBuffer.mBuffers[0].mData);
	Float32 * outputR = (Float32*)(outBuffer.mBuffers[1].mData);
	UInt32 nSampleFrames = inFramesToProcess;
	Float64 overallscale = 1.0;
	overallscale /= 44100.0;
	overallscale *= GetSampleRate();
	double inputSampleL;
	double inputSampleR;
	double mid;
	double side;
	//High Impact section
	Float64 stereowide = GetParameter( kParam_One );
	Float64 centersquish = GetParameter( kParam_Three );
	Float64 density = stereowide * 2.4;
	Float64 sustain = 1.0 - (1.0/(1.0 + (density/7.0)));
	//this way, enhance increases up to 50% and then mid falls off beyond that
	Float64 bridgerectifier;
	Float64 count;
	//Highpass section
	Float64 iirAmount = pow(GetParameter( kParam_Two ),3)/overallscale;
	Float64 tight = -0.33333333333333;
	Float64 offset;
	//we are setting it up so that to either extreme we can get an audible sound,
	//but sort of scaled so small adjustments don't shift the cutoff frequency yet.
	
	while (nSampleFrames-- > 0) {
		inputSampleL = *inputL;
		inputSampleR = *inputR;
		if (fabs(inputSampleL)<1.18e-23) inputSampleL = fpdL * 1.18e-17;
		if (fabs(inputSampleR)<1.18e-23) inputSampleR = fpdR * 1.18e-17;
		//assign working variables		
		mid = inputSampleL + inputSampleR;
		side = inputSampleL - inputSampleR;
		//assign mid and side. Now, High Impact code
		count = density;
		while (count > 1.0)
			{
				bridgerectifier = fabs(side)*1.57079633;
				if (bridgerectifier > 1.57079633) bridgerectifier = 1.57079633;
				//max value for sine function
				bridgerectifier = sin(bridgerectifier);
				if (side > 0.0) side = bridgerectifier;
				else side = -bridgerectifier;
				count = count - 1.0;
			}
		//we have now accounted for any really high density settings.
		bridgerectifier = fabs(side)*1.57079633;
		if (bridgerectifier > 1.57079633) bridgerectifier = 1.57079633;
		//max value for sine function
		bridgerectifier = sin(bridgerectifier);
		if (side > 0) side = (side*(1-count))+(bridgerectifier*count);
		else side = (side*(1-count))-(bridgerectifier*count);
		//blend according to density control
		//done first density. Next, sustain-reducer
		bridgerectifier = fabs(side)*1.57079633;
		if (bridgerectifier > 1.57079633) bridgerectifier = 1.57079633;
		bridgerectifier = (1-cos(bridgerectifier))*3.141592653589793;
		if (side > 0) side = (side*(1-sustain))+(bridgerectifier*sustain);
		else side = (side*(1-sustain))-(bridgerectifier*sustain);
		//done with High Impact code
		
		//now, Highpass code
		offset = 0.666666666666666 + ((1-fabs(side))*tight);
		if (offset < 0) offset = 0;
		if (offset > 1) offset = 1;
		if (flip)
			{
			iirSampleA = (iirSampleA * (1 - (offset * iirAmount))) + (side * (offset * iirAmount));
			side = side - iirSampleA;
			}
		else
			{
			iirSampleB = (iirSampleB * (1 - (offset * iirAmount))) + (side * (offset * iirAmount));
			side = side - iirSampleB;
			}
		//done with Highpass code
		
		bridgerectifier = fabs(mid)/1.273239544735162;
		if (bridgerectifier > 1.57079633) bridgerectifier = 1.57079633;
		bridgerectifier = sin(bridgerectifier)*1.273239544735162;
		if (mid > 0) mid = (mid*(1-centersquish))+(bridgerectifier*centersquish);
		else mid = (mid*(1-centersquish))-(bridgerectifier*centersquish);
		//done with the mid saturating section.
		
		inputSampleL = (mid+side)/2.0;
		inputSampleR = (mid-side)/2.0;
		flip = !flip;
		
		//begin 32 bit stereo floating point dither
		int expon; frexpf((float)inputSampleL, &expon);
		fpdL ^= fpdL << 13; fpdL ^= fpdL >> 17; fpdL ^= fpdL << 5;
		inputSampleL += ((double(fpdL)-uint32_t(0x7fffffff)) * 5.5e-36l * pow(2,expon+62));
		frexpf((float)inputSampleR, &expon);
		fpdR ^= fpdR << 13; fpdR ^= fpdR >> 17; fpdR ^= fpdR << 5;
		inputSampleR += ((double(fpdR)-uint32_t(0x7fffffff)) * 5.5e-36l * pow(2,expon+62));
		//end 32 bit stereo floating point dither
		
		*outputL = inputSampleL;
		*outputR = inputSampleR;
		//don't know why we're getting a volume boost, cursed thing
		
		inputL += 1;
		inputR += 1;
		outputL += 1;
		outputR += 1;
	}
return noErr;
}

