/* ========================================
 *  DeBez - DeBez.h
 *  Copyright (c) airwindows, Airwindows uses the MIT license
 * ======================================== */

#ifndef __DeBez_H
#include "DeBez.h"
#endif

void DeBez::processReplacing(float **inputs, float **outputs, VstInt32 sampleFrames) 
{
    float* in1  =  inputs[0];
    float* in2  =  inputs[1];
    float* out1 = outputs[0];
    float* out2 = outputs[1];

	VstInt32 inFramesToProcess = sampleFrames; //vst doesn't give us this as a separate variable so we'll make it
	double overallscale = 1.0;
	overallscale /= 44100.0;
	overallscale *= getSampleRate();
	
	rezA = rezB; rezB = A*2.0;
	bitA = bitB; bitB = B*2.0;
	wetA = wetB; wetB = C*2.0;
	
	bool steppedFreq = true; // Revised Bezier Undersampling
	if (rezB > 1.0) {  // has full rez at center, stepped
		steppedFreq = false; // to left, continuous to right
		rezB = 1.0-(rezB-1.0);
	} //if it's set up like that it's the revised algorithm
	rezB = fmin(fmax(pow(rezB,3.0),0.0005),1.0); //note: no overallscale, already inside undersampling
	int bezFreqFraction = (int)(1.0/rezB);
	double bezFreqTrim = (double)bezFreqFraction/(bezFreqFraction+1.0);
	if (steppedFreq) { //this hard-locks derez to exact subdivisions of 1.0
		rezB = 1.0 / bezFreqFraction;
		bezFreqTrim = 1.0-(rezB*bezFreqTrim);
	} else { //this makes it match the 1.0 case using stepped
		bezFreqTrim = 1.0-pow(rezB*0.5,1.0/(rezB*0.5));
	} //the revision more accurately connects the bezier curves
	
    while (--sampleFrames >= 0)
    {
		double inputSampleL = *in1;
		double inputSampleR = *in2;
		if (fabs(inputSampleL)<1.18e-23) inputSampleL = fpdL * 1.18e-17;
		if (fabs(inputSampleR)<1.18e-23) inputSampleR = fpdR * 1.18e-17;
		double drySampleL = inputSampleL;
		double drySampleR = inputSampleR;
		double temp = (double)sampleFrames/inFramesToProcess;
		double rez = (rezA*temp)+(rezB*(1.0-temp));
		double bit = ((bitA*temp)+(bitB*(1.0-temp)))-1.0;
		double wet = ((wetA*temp)+(wetB*(1.0-temp)))-1.0;
		double dry = 1.0 - wet;
		if (wet > 1.0) wet = 1.0;
		if (wet < -1.0) wet = -1.0;
		if (dry > 1.0) dry = 1.0;
		if (dry < 0.0) dry = 0.0;
		//this bitcrush can be subtracted.
		
		bezF[bez_cycle] += rez;
		bezF[bez_SampL] += (inputSampleL * rez);
		bezF[bez_SampR] += (inputSampleR * rez);
		if (bezF[bez_cycle] > 1.0) {
			if (steppedFreq) bezF[bez_cycle] = 0.0;
			else bezF[bez_cycle] -= 1.0;
			
			inputSampleL = (bezF[bez_SampL]+bezF[bez_AvgInSampL])*0.5;
			bezF[bez_AvgInSampL] = bezF[bez_SampL];
			inputSampleR = (bezF[bez_SampR]+bezF[bez_AvgInSampR])*0.5;
			bezF[bez_AvgInSampR] = bezF[bez_SampR];

			bool crushGate = (bit < 0.0);
			bit = 1.0-fabs(bit);
			bit = fmin(fmax(bit*16.0,0.5),16.0);
			double bitFactor = pow(2.0,bit);
			inputSampleL *= bitFactor;		
			inputSampleL = floor(inputSampleL+(crushGate?0.5/bitFactor:0.0));
			inputSampleL /= bitFactor;
			inputSampleR *= bitFactor;		
			inputSampleR = floor(inputSampleR+(crushGate?0.5/bitFactor:0.0));
			inputSampleR /= bitFactor;
			//derez inside debez
			bezF[bez_CL] = bezF[bez_BL];
			bezF[bez_BL] = bezF[bez_AL];
			bezF[bez_AL] = inputSampleL;
			bezF[bez_SampL] = 0.0;
			bezF[bez_CR] = bezF[bez_BR];
			bezF[bez_BR] = bezF[bez_AR];
			bezF[bez_AR] = inputSampleR;
			bezF[bez_SampR] = 0.0;
		}
		double X = bezF[bez_cycle]*bezFreqTrim;
		double CBLfreq = (bezF[bez_CL]*(1.0-X))+(bezF[bez_BL]*X);
		double BALfreq = (bezF[bez_BL]*(1.0-X))+(bezF[bez_AL]*X);
		double CBALfreq = (bezF[bez_BL]+(CBLfreq*(1.0-X))+(BALfreq*X))*0.125;
		inputSampleL = CBALfreq+bezF[bez_AvgOutSampL]; bezF[bez_AvgOutSampL] = CBALfreq;
		
		double CBRfreq = (bezF[bez_CR]*(1.0-X))+(bezF[bez_BR]*X);
		double BARfreq = (bezF[bez_BR]*(1.0-X))+(bezF[bez_AR]*X);
		double CBARfreq = (bezF[bez_BR]+(CBRfreq*(1.0-X))+(BARfreq*X))*0.125;
		inputSampleR = CBARfreq+bezF[bez_AvgOutSampR]; bezF[bez_AvgOutSampR] = CBARfreq;
		
		inputSampleL = (wet*inputSampleL)+(dry*drySampleL);
		inputSampleR = (wet*inputSampleR)+(dry*drySampleR);
		
		//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
		
		*out1 = inputSampleL;
		*out2 = inputSampleR;

		in1++;
		in2++;
		out1++;
		out2++;
    }
}

void DeBez::processDoubleReplacing(double **inputs, double **outputs, VstInt32 sampleFrames) 
{
    double* in1  =  inputs[0];
    double* in2  =  inputs[1];
    double* out1 = outputs[0];
    double* out2 = outputs[1];

	VstInt32 inFramesToProcess = sampleFrames; //vst doesn't give us this as a separate variable so we'll make it
	double overallscale = 1.0;
	overallscale /= 44100.0;
	overallscale *= getSampleRate();
	
	rezA = rezB; rezB = A*2.0;
	bitA = bitB; bitB = B*2.0;
	wetA = wetB; wetB = C*2.0;
	
	bool steppedFreq = true; // Revised Bezier Undersampling
	if (rezB > 1.0) {  // has full rez at center, stepped
		steppedFreq = false; // to left, continuous to right
		rezB = 1.0-(rezB-1.0);
	} //if it's set up like that it's the revised algorithm
	rezB = fmin(fmax(pow(rezB,3.0),0.0005),1.0); //note: no overallscale, already inside undersampling
	int bezFreqFraction = (int)(1.0/rezB);
	double bezFreqTrim = (double)bezFreqFraction/(bezFreqFraction+1.0);
	if (steppedFreq) { //this hard-locks derez to exact subdivisions of 1.0
		rezB = 1.0 / bezFreqFraction;
		bezFreqTrim = 1.0-(rezB*bezFreqTrim);
	} else { //this makes it match the 1.0 case using stepped
		bezFreqTrim = 1.0-pow(rezB*0.5,1.0/(rezB*0.5));
	} //the revision more accurately connects the bezier curves
	
    while (--sampleFrames >= 0)
    {
		double inputSampleL = *in1;
		double inputSampleR = *in2;
		if (fabs(inputSampleL)<1.18e-23) inputSampleL = fpdL * 1.18e-17;
		if (fabs(inputSampleR)<1.18e-23) inputSampleR = fpdR * 1.18e-17;
		double drySampleL = inputSampleL;
		double drySampleR = inputSampleR;
		double temp = (double)sampleFrames/inFramesToProcess;
		double rez = (rezA*temp)+(rezB*(1.0-temp));
		double bit = ((bitA*temp)+(bitB*(1.0-temp)))-1.0;
		double wet = ((wetA*temp)+(wetB*(1.0-temp)))-1.0;
		double dry = 1.0 - wet;
		if (wet > 1.0) wet = 1.0;
		if (wet < -1.0) wet = -1.0;
		if (dry > 1.0) dry = 1.0;
		if (dry < 0.0) dry = 0.0;
		//this bitcrush can be subtracted.
		
		bezF[bez_cycle] += rez;
		bezF[bez_SampL] += (inputSampleL * rez);
		bezF[bez_SampR] += (inputSampleR * rez);
		if (bezF[bez_cycle] > 1.0) {
			if (steppedFreq) bezF[bez_cycle] = 0.0;
			else bezF[bez_cycle] -= 1.0;
			
			inputSampleL = (bezF[bez_SampL]+bezF[bez_AvgInSampL])*0.5;
			bezF[bez_AvgInSampL] = bezF[bez_SampL];
			inputSampleR = (bezF[bez_SampR]+bezF[bez_AvgInSampR])*0.5;
			bezF[bez_AvgInSampR] = bezF[bez_SampR];
			
			bool crushGate = (bit < 0.0);
			bit = 1.0-fabs(bit);
			bit = fmin(fmax(bit*16.0,0.5),16.0);
			double bitFactor = pow(2.0,bit);
			inputSampleL *= bitFactor;		
			inputSampleL = floor(inputSampleL+(crushGate?0.5/bitFactor:0.0));
			inputSampleL /= bitFactor;
			inputSampleR *= bitFactor;		
			inputSampleR = floor(inputSampleR+(crushGate?0.5/bitFactor:0.0));
			inputSampleR /= bitFactor;
			//derez inside debez
			bezF[bez_CL] = bezF[bez_BL];
			bezF[bez_BL] = bezF[bez_AL];
			bezF[bez_AL] = inputSampleL;
			bezF[bez_SampL] = 0.0;
			bezF[bez_CR] = bezF[bez_BR];
			bezF[bez_BR] = bezF[bez_AR];
			bezF[bez_AR] = inputSampleR;
			bezF[bez_SampR] = 0.0;
		}
		double X = bezF[bez_cycle]*bezFreqTrim;
		double CBLfreq = (bezF[bez_CL]*(1.0-X))+(bezF[bez_BL]*X);
		double BALfreq = (bezF[bez_BL]*(1.0-X))+(bezF[bez_AL]*X);
		double CBALfreq = (bezF[bez_BL]+(CBLfreq*(1.0-X))+(BALfreq*X))*0.125;
		inputSampleL = CBALfreq+bezF[bez_AvgOutSampL]; bezF[bez_AvgOutSampL] = CBALfreq;
		
		double CBRfreq = (bezF[bez_CR]*(1.0-X))+(bezF[bez_BR]*X);
		double BARfreq = (bezF[bez_BR]*(1.0-X))+(bezF[bez_AR]*X);
		double CBARfreq = (bezF[bez_BR]+(CBRfreq*(1.0-X))+(BARfreq*X))*0.125;
		inputSampleR = CBARfreq+bezF[bez_AvgOutSampR]; bezF[bez_AvgOutSampR] = CBARfreq;
				
		inputSampleL = (wet*inputSampleL)+(dry*drySampleL);
		inputSampleR = (wet*inputSampleR)+(dry*drySampleR);
		
		//begin 64 bit stereo floating point dither
		//int expon; frexp((double)inputSampleL, &expon);
		fpdL ^= fpdL << 13; fpdL ^= fpdL >> 17; fpdL ^= fpdL << 5;
		//inputSampleL += ((double(fpdL)-uint32_t(0x7fffffff)) * 1.1e-44l * pow(2,expon+62));
		//frexp((double)inputSampleR, &expon);
		fpdR ^= fpdR << 13; fpdR ^= fpdR >> 17; fpdR ^= fpdR << 5;
		//inputSampleR += ((double(fpdR)-uint32_t(0x7fffffff)) * 1.1e-44l * pow(2,expon+62));
		//end 64 bit stereo floating point dither
		
		*out1 = inputSampleL;
		*out2 = inputSampleR;

		in1++;
		in2++;
		out1++;
		out2++;
    }
}