/*
*	File:		Lowpass2.cpp
*	
*	Version:	1.0
* 
*	Created:	3/13/19
*	
*	Copyright:  Copyright © 2019 Airwindows, Airwindows uses the MIT license
* 
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/*=============================================================================
	Lowpass2.cpp
	
=============================================================================*/
#include "Lowpass2.h"


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

COMPONENT_ENTRY(Lowpass2)


//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	Lowpass2::Lowpass2
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Lowpass2::Lowpass2(AudioUnit component)
	: AUEffectBase(component)
{
	CreateElements();
	Globals()->UseIndexedParameters(kNumberOfParameters);
	SetParameter(kParam_One, kDefaultValue_ParamOne );
	SetParameter(kParam_Two, kDefaultValue_ParamTwo );
	SetParameter(kParam_Three, kDefaultValue_ParamThree );
	SetParameter(kParam_Four, kDefaultValue_ParamFour );
         
#if AU_DEBUG_DISPATCHER
	mDebugDispatcher = new AUDebugDispatcher (this);
#endif
	
}


//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	Lowpass2::GetParameterValueStrings
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ComponentResult			Lowpass2::GetParameterValueStrings(AudioUnitScope		inScope,
                                                                AudioUnitParameterID	inParameterID,
                                                                CFArrayRef *		outStrings)
{
        
    return kAudioUnitErr_InvalidProperty;
}



//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	Lowpass2::GetParameterInfo
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ComponentResult			Lowpass2::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 = -1.0;
                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 = 4.0;
                outParameterInfo.defaultValue = kDefaultValue_ParamThree;
                break;
           case kParam_Four:
                AUBase::FillInParameterName (outParameterInfo, kParameterFourName, false);
                outParameterInfo.unit = kAudioUnitParameterUnit_Generic;
                outParameterInfo.minValue = 0.0;
                outParameterInfo.maxValue = 1.0;
                outParameterInfo.defaultValue = kDefaultValue_ParamFour;
                break;
           default:
                result = kAudioUnitErr_InvalidParameter;
                break;
            }
	} else {
        result = kAudioUnitErr_InvalidParameter;
    }
    


	return result;
}

//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	Lowpass2::GetPropertyInfo
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ComponentResult			Lowpass2::GetPropertyInfo (AudioUnitPropertyID	inID,
                                                        AudioUnitScope		inScope,
                                                        AudioUnitElement	inElement,
                                                        UInt32 &		outDataSize,
                                                        Boolean &		outWritable)
{
	return AUEffectBase::GetPropertyInfo (inID, inScope, inElement, outDataSize, outWritable);
}

//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	Lowpass2::GetProperty
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ComponentResult			Lowpass2::GetProperty(	AudioUnitPropertyID inID,
                                                        AudioUnitScope 		inScope,
                                                        AudioUnitElement 	inElement,
                                                        void *			outData )
{
	return AUEffectBase::GetProperty (inID, inScope, inElement, outData);
}

//	Lowpass2::Initialize
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ComponentResult Lowpass2::Initialize()
{
    ComponentResult result = AUEffectBase::Initialize();
    if (result == noErr)
        Reset(kAudioUnitScope_Global, 0);
    return result;
}

#pragma mark ____Lowpass2EffectKernel



//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	Lowpass2::Lowpass2Kernel::Reset()
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
void		Lowpass2::Lowpass2Kernel::Reset()
{
	iirSampleA = 0.0;
	iirSampleB = 0.0;
	iirSampleC = 0.0;
	iirSampleD = 0.0;
	iirSampleE = 0.0;
	iirSampleF = 0.0;
	iirSampleG = 0.0;
	iirSampleH = 0.0;
	fpd = 1.0; while (fpd < 16386) fpd = rand()*UINT32_MAX;
	fpFlip = true;
}

//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//	Lowpass2::Lowpass2Kernel::Process
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
void		Lowpass2::Lowpass2Kernel::Process(	const Float32 	*inSourceP,
                                                    Float32		 	*inDestP,
                                                    UInt32 			inFramesToProcess,
                                                    UInt32			inNumChannels, 
                                                    bool			&ioSilence )
{
	UInt32 nSampleFrames = inFramesToProcess;
	const Float32 *sourceP = inSourceP;
	Float32 *destP = inDestP;
	Float64 iirAmount = GetParameter( kParam_One );
	Float64 tight = GetParameter( kParam_Two );
	if (iirAmount < 0.0000001) iirAmount = 0.0000001;
	if (iirAmount > 1) iirAmount = 1;
	if (tight < 0.0) tight *= 0.5;
	Float64 offset;
	Float64 aWet = 1.0;
	Float64 bWet = 1.0;
	Float64 cWet = 1.0;
	Float64 dWet = GetParameter( kParam_Three );
	//four-stage wet/dry control using progressive stages that bypass when not engaged
	if (dWet < 1.0) {aWet = dWet; bWet = 0.0; cWet = 0.0; dWet = 0.0;}
	else if (dWet < 2.0) {bWet = dWet - 1.0; cWet = 0.0; dWet = 0.0;}
	else if (dWet < 3.0) {cWet = dWet - 2.0; dWet = 0.0;}
	else {dWet -= 3.0;}
	//this is one way to make a little set of dry/wet stages that are successively added to the
	//output as the control is turned up. Each one independently goes from 0-1 and stays at 1
	//beyond that point: this is a way to progressively add a 'black box' sound processing
	//which lets you fall through to simpler processing at lower settings.
	Float64 wet = GetParameter( kParam_Four );
	
	while (nSampleFrames-- > 0) {
		double inputSample = *sourceP;

		if (fabs(inputSample)<1.18e-23) inputSample = fpd * 1.18e-17;
		double drySample = inputSample;
		
		if (tight > 0) offset = (1 - tight) + (fabs(inputSample)*tight);
		else offset = (1 + tight) + ((1-fabs(inputSample))*tight);
		if (offset < 0.0000001) offset = 0.0000001; if (offset > 1) offset = 1;

		if (fpFlip)
		{
			if (aWet > 0.0) {
				iirSampleA = (iirSampleA * (1 - (offset * iirAmount))) + (inputSample * (offset * iirAmount));
				inputSample = (iirSampleA * aWet) + (inputSample * (1.0-aWet));
			}
			if (bWet > 0.0) {
				iirSampleC = (iirSampleC * (1 - (offset * iirAmount))) + (inputSample * (offset * iirAmount));
				inputSample = (iirSampleC * bWet) + (inputSample * (1.0-bWet));
			}
			if (cWet > 0.0) {
				iirSampleE = (iirSampleE * (1 - (offset * iirAmount))) + (inputSample * (offset * iirAmount));
				inputSample = (iirSampleE * cWet) + (inputSample * (1.0-cWet));
			}
			if (dWet > 0.0) {
				iirSampleG = (iirSampleG * (1 - (offset * iirAmount))) + (inputSample * (offset * iirAmount));
				inputSample = (iirSampleG * dWet) + (inputSample * (1.0-dWet));
			}
		}
		else
		{
			if (aWet > 0.0) {
				iirSampleB = (iirSampleB * (1 - (offset * iirAmount))) + (inputSample * (offset * iirAmount));
				inputSample = (iirSampleB * aWet) + (inputSample * (1.0-aWet));
			}
			if (bWet > 0.0) {
				iirSampleD = (iirSampleD * (1 - (offset * iirAmount))) + (inputSample * (offset * iirAmount));
				inputSample = (iirSampleD * bWet) + (inputSample * (1.0-bWet));
			}
			if (cWet > 0.0) {
				iirSampleF = (iirSampleF * (1 - (offset * iirAmount))) + (inputSample * (offset * iirAmount));
				inputSample = (iirSampleF * cWet) + (inputSample * (1.0-cWet));
			}
			if (dWet > 0.0) {
				iirSampleH = (iirSampleH * (1 - (offset * iirAmount))) + (inputSample * (offset * iirAmount));
				inputSample = (iirSampleH * dWet) + (inputSample * (1.0-dWet));
			}
		}
		
		if (wet !=1.0) {
			inputSample = (inputSample * wet) + (drySample * (1.0-wet));
		}
		//Dry/Wet control, defaults to the last slider
		fpFlip = !fpFlip;

		//begin 32 bit floating point dither
		int expon; frexpf((float)inputSample, &expon);
		fpd ^= fpd << 13; fpd ^= fpd >> 17; fpd ^= fpd << 5;
		inputSample += ((double(fpd)-uint32_t(0x7fffffff)) * 5.5e-36l * pow(2,expon+62));
		//end 32 bit floating point dither
		
		*destP = inputSample;
		
		sourceP += inNumChannels; destP += inNumChannels;
	}
}

