/* ========================================
 *  ButterComp - ButterComp.h
 *  Copyright (c) 2016 airwindows, All rights reserved
 * ======================================== */

#ifndef __ButterComp_H
#include "ButterComp.h"
#endif

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

	double overallscale = 1.0;
	overallscale /= 44100.0;
	overallscale *= getSampleRate();

	double inputposL;
	double inputnegL;
	double calcposL;
	double calcnegL;
	double outputposL;
	double outputnegL;
	long double totalmultiplierL;
	long double inputSampleL;
	double drySampleL;

	double inputposR;
	double inputnegR;
	double calcposR;
	double calcnegR;
	double outputposR;
	double outputnegR;
	long double totalmultiplierR;
	long double inputSampleR;
	double drySampleR;

	double inputgain = pow(10.0,(A*14.0)/20.0);
	double wet = B;
	double dry = 1.0 - wet;
	double outputgain = inputgain;
	outputgain -= 1.0;
	outputgain /= 1.5;
	outputgain += 1.0;
	double divisor = 0.012 * (A / 135.0);
	divisor /= overallscale;
	double remainder = divisor;
	divisor = 1.0 - divisor;
    
    while (--sampleFrames >= 0)
    {
		inputSampleL = *in1;
		inputSampleR = *in2;
		if (inputSampleL<1.2e-38 && -inputSampleL<1.2e-38) {
			static int noisesource = 0;
			//this declares a variable before anything else is compiled. It won't keep assigning
			//it to 0 for every sample, it's as if the declaration doesn't exist in this context,
			//but it lets me add this denormalization fix in a single place rather than updating
			//it in three different locations. The variable isn't thread-safe but this is only
			//a random seed and we can share it with whatever.
			noisesource = noisesource % 1700021; noisesource++;
			int residue = noisesource * noisesource;
			residue = residue % 170003; residue *= residue;
			residue = residue % 17011; residue *= residue;
			residue = residue % 1709; residue *= residue;
			residue = residue % 173; residue *= residue;
			residue = residue % 17;
			double applyresidue = residue;
			applyresidue *= 0.00000001;
			applyresidue *= 0.00000001;
			inputSampleL = applyresidue;
		}
		if (inputSampleR<1.2e-38 && -inputSampleR<1.2e-38) {
			static int noisesource = 0;
			noisesource = noisesource % 1700021; noisesource++;
			int residue = noisesource * noisesource;
			residue = residue % 170003; residue *= residue;
			residue = residue % 17011; residue *= residue;
			residue = residue % 1709; residue *= residue;
			residue = residue % 173; residue *= residue;
			residue = residue % 17;
			double applyresidue = residue;
			applyresidue *= 0.00000001;
			applyresidue *= 0.00000001;
			inputSampleR = applyresidue;
			//this denormalization routine produces a white noise at -300 dB which the noise
			//shaping will interact with to produce a bipolar output, but the noise is actually
			//all positive. That should stop any variables from going denormal, and the routine
			//only kicks in if digital black is input. As a final touch, if you save to 24-bit
			//the silence will return to being digital black again.
		}
		drySampleL = inputSampleL;
		drySampleR = inputSampleR;
		
		inputSampleL *= inputgain;
		inputSampleR *= inputgain;
		
		inputposL = inputSampleL + 1.0;
		if (inputposL < 0.0) inputposL = 0.0;
		outputposL = inputposL / 2.0;
		if (outputposL > 1.0) outputposL = 1.0;		
		inputposL *= inputposL;
		targetposL *= divisor;
		targetposL += (inputposL * remainder);
		calcposL = pow((1.0/targetposL),2);
		
		inputnegL = (-inputSampleL) + 1.0;
		if (inputnegL < 0.0) inputnegL = 0.0;
		outputnegL = inputnegL / 2.0;
		if (outputnegL > 1.0) outputnegL = 1.0;		
		inputnegL *= inputnegL;
		targetnegL *= divisor;
		targetnegL += (inputnegL * remainder);
		calcnegL = pow((1.0/targetnegL),2);
		//now we have mirrored targets for comp
		//outputpos and outputneg go from 0 to 1
		
		inputposR = inputSampleR + 1.0;
		if (inputposR < 0.0) inputposR = 0.0;
		outputposR = inputposR / 2.0;
		if (outputposR > 1.0) outputposR = 1.0;		
		inputposR *= inputposR;
		targetposR *= divisor;
		targetposR += (inputposR * remainder);
		calcposR = pow((1.0/targetposR),2);
		
		inputnegR = (-inputSampleR) + 1.0;
		if (inputnegR < 0.0) inputnegR = 0.0;
		outputnegR = inputnegR / 2.0;
		if (outputnegR > 1.0) outputnegR = 1.0;		
		inputnegR *= inputnegR;
		targetnegR *= divisor;
		targetnegR += (inputnegR * remainder);
		calcnegR = pow((1.0/targetnegR),2);
		//now we have mirrored targets for comp
		//outputpos and outputneg go from 0 to 1
		
		
		if (inputSampleL > 0)
		{ //working on pos
			controlAposL *= divisor;
			controlAposL += (calcposL*remainder);
		}
		else
		{ //working on neg
			controlAnegL *= divisor;
			controlAnegL += (calcnegL*remainder);
		}
		//this causes each of the four to update only when active and in the correct 'flip'
		
		if (inputSampleR > 0)
		{ //working on pos
			controlAposR *= divisor;
			controlAposR += (calcposR*remainder);
		}
		else
		{ //working on neg
			controlAnegR *= divisor;
			controlAnegR += (calcnegR*remainder);
		}
		//this causes each of the four to update only when active and in the correct 'flip'
		
		totalmultiplierL = (controlAposL * outputposL) + (controlAnegL * outputnegL);
		totalmultiplierR = (controlAposR * outputposR) + (controlAnegR * outputnegR);
		//this combines the sides according to flip, blending relative to the input value
		
		inputSampleL *= totalmultiplierL;
		inputSampleL /= outputgain;
		
		inputSampleR *= totalmultiplierR;
		inputSampleR /= outputgain;
		
		if (wet !=1.0) {
			inputSampleL = (inputSampleL * wet) + (drySampleL * dry);
			inputSampleR = (inputSampleR * wet) + (drySampleR * dry);
		}
		
		//stereo 32 bit dither, made small and tidy.
		int expon; frexpf((float)inputSampleL, &expon);
		long double dither = (rand()/(RAND_MAX*7.737125245533627e+25))*pow(2,expon+62);
		inputSampleL += (dither-fpNShapeL); fpNShapeL = dither;
		frexpf((float)inputSampleR, &expon);
		dither = (rand()/(RAND_MAX*7.737125245533627e+25))*pow(2,expon+62);
		inputSampleR += (dither-fpNShapeR); fpNShapeR = dither;
		//end 32 bit dither

		*out1 = inputSampleL;
		*out2 = inputSampleR;

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

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

	double overallscale = 1.0;
	overallscale /= 44100.0;
	overallscale *= getSampleRate();
	
	double inputposL;
	double inputnegL;
	double calcposL;
	double calcnegL;
	double outputposL;
	double outputnegL;
	long double totalmultiplierL;
	long double inputSampleL;
	double drySampleL;
	
	double inputposR;
	double inputnegR;
	double calcposR;
	double calcnegR;
	double outputposR;
	double outputnegR;
	long double totalmultiplierR;
	long double inputSampleR;
	double drySampleR;
	
	double inputgain = pow(10.0,(A*14.0)/20.0);
	double wet = B;
	double dry = 1.0 - wet;
	double outputgain = inputgain;
	outputgain -= 1.0;
	outputgain /= 1.5;
	outputgain += 1.0;
	double divisor = 0.012 * (A / 135.0);
	divisor /= overallscale;
	double remainder = divisor;
	divisor = 1.0 - divisor;
    
    while (--sampleFrames >= 0)
    {
		inputSampleL = *in1;
		inputSampleR = *in2;
		if (inputSampleL<1.2e-38 && -inputSampleL<1.2e-38) {
			static int noisesource = 0;
			//this declares a variable before anything else is compiled. It won't keep assigning
			//it to 0 for every sample, it's as if the declaration doesn't exist in this context,
			//but it lets me add this denormalization fix in a single place rather than updating
			//it in three different locations. The variable isn't thread-safe but this is only
			//a random seed and we can share it with whatever.
			noisesource = noisesource % 1700021; noisesource++;
			int residue = noisesource * noisesource;
			residue = residue % 170003; residue *= residue;
			residue = residue % 17011; residue *= residue;
			residue = residue % 1709; residue *= residue;
			residue = residue % 173; residue *= residue;
			residue = residue % 17;
			double applyresidue = residue;
			applyresidue *= 0.00000001;
			applyresidue *= 0.00000001;
			inputSampleL = applyresidue;
		}
		if (inputSampleR<1.2e-38 && -inputSampleR<1.2e-38) {
			static int noisesource = 0;
			noisesource = noisesource % 1700021; noisesource++;
			int residue = noisesource * noisesource;
			residue = residue % 170003; residue *= residue;
			residue = residue % 17011; residue *= residue;
			residue = residue % 1709; residue *= residue;
			residue = residue % 173; residue *= residue;
			residue = residue % 17;
			double applyresidue = residue;
			applyresidue *= 0.00000001;
			applyresidue *= 0.00000001;
			inputSampleR = applyresidue;
			//this denormalization routine produces a white noise at -300 dB which the noise
			//shaping will interact with to produce a bipolar output, but the noise is actually
			//all positive. That should stop any variables from going denormal, and the routine
			//only kicks in if digital black is input. As a final touch, if you save to 24-bit
			//the silence will return to being digital black again.
		}
		drySampleL = inputSampleL;
		drySampleR = inputSampleR;
		
		inputSampleL *= inputgain;
		inputSampleR *= inputgain;
		
		inputposL = inputSampleL + 1.0;
		if (inputposL < 0.0) inputposL = 0.0;
		outputposL = inputposL / 2.0;
		if (outputposL > 1.0) outputposL = 1.0;		
		inputposL *= inputposL;
		targetposL *= divisor;
		targetposL += (inputposL * remainder);
		calcposL = pow((1.0/targetposL),2);
		
		inputnegL = (-inputSampleL) + 1.0;
		if (inputnegL < 0.0) inputnegL = 0.0;
		outputnegL = inputnegL / 2.0;
		if (outputnegL > 1.0) outputnegL = 1.0;		
		inputnegL *= inputnegL;
		targetnegL *= divisor;
		targetnegL += (inputnegL * remainder);
		calcnegL = pow((1.0/targetnegL),2);
		//now we have mirrored targets for comp
		//outputpos and outputneg go from 0 to 1
		
		inputposR = inputSampleR + 1.0;
		if (inputposR < 0.0) inputposR = 0.0;
		outputposR = inputposR / 2.0;
		if (outputposR > 1.0) outputposR = 1.0;		
		inputposR *= inputposR;
		targetposR *= divisor;
		targetposR += (inputposR * remainder);
		calcposR = pow((1.0/targetposR),2);
		
		inputnegR = (-inputSampleR) + 1.0;
		if (inputnegR < 0.0) inputnegR = 0.0;
		outputnegR = inputnegR / 2.0;
		if (outputnegR > 1.0) outputnegR = 1.0;		
		inputnegR *= inputnegR;
		targetnegR *= divisor;
		targetnegR += (inputnegR * remainder);
		calcnegR = pow((1.0/targetnegR),2);
		//now we have mirrored targets for comp
		//outputpos and outputneg go from 0 to 1
		
		
		if (inputSampleL > 0)
		{ //working on pos
			controlAposL *= divisor;
			controlAposL += (calcposL*remainder);
		}
		else
		{ //working on neg
			controlAnegL *= divisor;
			controlAnegL += (calcnegL*remainder);
		}
		//this causes each of the four to update only when active and in the correct 'flip'
		
		if (inputSampleR > 0)
		{ //working on pos
			controlAposR *= divisor;
			controlAposR += (calcposR*remainder);
		}
		else
		{ //working on neg
			controlAnegR *= divisor;
			controlAnegR += (calcnegR*remainder);
		}
		//this causes each of the four to update only when active and in the correct 'flip'
		
		totalmultiplierL = (controlAposL * outputposL) + (controlAnegL * outputnegL);
		totalmultiplierR = (controlAposR * outputposR) + (controlAnegR * outputnegR);
		//this combines the sides according to flip, blending relative to the input value
		
		inputSampleL *= totalmultiplierL;
		inputSampleL /= outputgain;
		
		inputSampleR *= totalmultiplierR;
		inputSampleR /= outputgain;
		
		if (wet !=1.0) {
			inputSampleL = (inputSampleL * wet) + (drySampleL * dry);
			inputSampleR = (inputSampleR * wet) + (drySampleR * dry);
		}
		
		//stereo 64 bit dither, made small and tidy.
		int expon; frexp((double)inputSampleL, &expon);
		long double dither = (rand()/(RAND_MAX*7.737125245533627e+25))*pow(2,expon+62);
		dither /= 536870912.0; //needs this to scale to 64 bit zone
		inputSampleL += (dither-fpNShapeL); fpNShapeL = dither;
		frexp((double)inputSampleR, &expon);
		dither = (rand()/(RAND_MAX*7.737125245533627e+25))*pow(2,expon+62);
		dither /= 536870912.0; //needs this to scale to 64 bit zone
		inputSampleR += (dither-fpNShapeR); fpNShapeR = dither;
		//end 64 bit dither
		
		*out1 = inputSampleL;
		*out2 = inputSampleR;

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