/* ========================================
 *  Desk4 - Desk4.h
 *  Copyright (c) 2016 airwindows, Airwindows uses the MIT license
 * ======================================== */

#include "Desk4.h"

#ifdef SHR3D_SFX_CORE_AIRWINDOWS

namespace airwinconsolidated::Desk4 {

void Desk4::processBlock(float **inputs, float **outputs, int 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 gain = (pow(A,2)*10)+0.0001;
	double gaintrim = (pow(A,2)*2)+1.0;
	double slewgain = (pow(B,3)*40)+0.0001;	
	double prevslew = 0.105;
	double intensity = (pow(C,6)*15)+0.0001;
	double depthA = (pow(D,4)*940)+0.00001;
	int offsetA = (int)(depthA * overallscale);
	if (offsetA < 1) offsetA = 1;
	if (offsetA > 4880) offsetA = 4880;
	double balanceB = 0.0001;	
	slewgain *= overallscale;
	prevslew *= overallscale;
	balanceB /= overallscale;
	double outputgain = E;
	double wet = F;
	//removed extra dry variable
	
	double clampL;
	double clampR;
	double thicknessL;
	double thicknessR;
	double out;
	double balanceA = 1.0 - balanceB;
	double bridgerectifier;
	double slewL;
	double slewR;
	double combSampleL;
	double combSampleR;
	double drySampleL;
	double drySampleR;
	double inputSampleL;
	double inputSampleR;

    while (--sampleFrames >= 0)
    {
		inputSampleL = *in1;
		inputSampleR = *in2;
		if (fabs(inputSampleL)<1.18e-23) inputSampleL = fpdL * 1.18e-17;
		if (fabs(inputSampleR)<1.18e-23) inputSampleR = fpdR * 1.18e-17;
		drySampleL = inputSampleL;
		drySampleR = inputSampleR;

		if (gcount < 0 || gcount > 4900) {gcount = 4900;}
		
		dL[gcount+4900] = dL[gcount] = fabs(inputSampleL)*intensity;
		controlL += (dL[gcount] / offsetA);
		controlL -= (dL[gcount+offsetA] / offsetA);
		controlL -= 0.000001;
		clampL = 1;
		if (controlL < 0) {controlL = 0;}
		if (controlL > 1) {clampL -= (controlL - 1); controlL = 1;}
		if (clampL < 0.5) {clampL = 0.5;}
		
		dR[gcount+4900] = dR[gcount] = fabs(inputSampleR)*intensity;
		controlR += (dR[gcount] / offsetA);
		controlR -= (dR[gcount+offsetA] / offsetA);
		controlR -= 0.000001;
		clampR = 1;
		if (controlR < 0) {controlR = 0;}
		if (controlR > 1) {clampR -= (controlR - 1); controlR = 1;}
		if (clampR < 0.5) {clampR = 0.5;}
		
		
		gcount--;
		//control = 0 to 1
		thicknessL = ((1.0 - controlL) * 2.0) - 1.0;
		thicknessR = ((1.0 - controlR) * 2.0) - 1.0;
		
		out = fabs(thicknessL);		
		bridgerectifier = fabs(inputSampleL);
		if (bridgerectifier > 1.57079633) bridgerectifier = 1.57079633;
		//max value for sine function
		if (thicknessL > 0) bridgerectifier = sin(bridgerectifier);
		else bridgerectifier = 1-cos(bridgerectifier);
		//produce either boosted or starved version
		if (inputSampleL > 0) inputSampleL = (inputSampleL*(1-out))+(bridgerectifier*out);
		else inputSampleL = (inputSampleL*(1-out))-(bridgerectifier*out);
		//blend according to density control
		
		out = fabs(thicknessR);		
		bridgerectifier = fabs(inputSampleR);
		if (bridgerectifier > 1.57079633) bridgerectifier = 1.57079633;
		//max value for sine function
		if (thicknessR > 0) bridgerectifier = sin(bridgerectifier);
		else bridgerectifier = 1-cos(bridgerectifier);
		//produce either boosted or starved version
		if (inputSampleR > 0) inputSampleR = (inputSampleR*(1-out))+(bridgerectifier*out);
		else inputSampleR = (inputSampleR*(1-out))-(bridgerectifier*out);
		//blend according to density control
		
		inputSampleL *= clampL;
		inputSampleR *= clampR;
		
		slewL = inputSampleL - lastSampleL;
		lastSampleL = inputSampleL;
		//Set up direct reference for slew
		
		slewR = inputSampleR - lastSampleR;
		lastSampleR = inputSampleR;
		//Set up direct reference for slew
		
		bridgerectifier = fabs(slewL*slewgain);
		if (bridgerectifier > 1.57079633) bridgerectifier = 1.0;
		else bridgerectifier = sin(bridgerectifier);
		if (slewL > 0) slewL = bridgerectifier/slewgain;
		else slewL = -(bridgerectifier/slewgain);
		
		bridgerectifier = fabs(slewR*slewgain);
		if (bridgerectifier > 1.57079633) bridgerectifier = 1.0;
		else bridgerectifier = sin(bridgerectifier);
		if (slewR > 0) slewR = bridgerectifier/slewgain;
		else slewR = -(bridgerectifier/slewgain);
		
		inputSampleL = (lastOutSampleL*balanceA) + (lastSampleL*balanceB) + slewL;
		//go from last slewed, but include some raw values
		lastOutSampleL = inputSampleL;
		//Set up slewed reference
		
		inputSampleR = (lastOutSampleR*balanceA) + (lastSampleR*balanceB) + slewR;
		//go from last slewed, but include some raw values
		lastOutSampleR = inputSampleR;
		//Set up slewed reference
		
		combSampleL = fabs(drySampleL*lastSampleL);
		if (combSampleL > 1.0) combSampleL = 1.0;
		//bailout for very high input gains
		
		combSampleR = fabs(drySampleR*lastSampleR);
		if (combSampleR > 1.0) combSampleR = 1.0;
		//bailout for very high input gains
		
		inputSampleL -= (lastSlewL * combSampleL * prevslew);
		lastSlewL = slewL;
		//slew interaction with previous slew
		
		inputSampleR -= (lastSlewR * combSampleR * prevslew);
		lastSlewR = slewR;
		//slew interaction with previous slew
		
		inputSampleL *= gain;
		bridgerectifier = fabs(inputSampleL);
		if (bridgerectifier > 1.57079633) bridgerectifier = 1.0;
		else bridgerectifier = sin(bridgerectifier);
		if (inputSampleL > 0) inputSampleL = bridgerectifier;
		else inputSampleL = -bridgerectifier;
		//drive section
		inputSampleL /= gain;
		inputSampleL *= gaintrim;
		//end of Desk section
		
		inputSampleR *= gain;
		bridgerectifier = fabs(inputSampleR);
		if (bridgerectifier > 1.57079633) bridgerectifier = 1.0;
		else bridgerectifier = sin(bridgerectifier);
		if (inputSampleR > 0) inputSampleR = bridgerectifier;
		else inputSampleR = -bridgerectifier;
		//drive section
		inputSampleR /= gain;
		inputSampleR *= gaintrim;
		//end of Desk section
		
		if (outputgain != 1.0) {
			inputSampleL *= outputgain;
			inputSampleR *= outputgain;
		}
		
		if (wet !=1.0) {
			inputSampleL = (inputSampleL * wet) + (drySampleL * (1.0-wet));
			inputSampleR = (inputSampleR * wet) + (drySampleR * (1.0-wet));
		}
		
		
		//begin 32 bit stereo floating point dither
		int expon; frexpf((float)inputSampleL, &expon);
		fpdL ^= fpdL << 13; fpdL ^= fpdL >> 17; fpdL ^= fpdL << 5;
		inputSampleL += double((double(fpdL)-uint32_t(0x7fffffff)) * 5.5e-36l * pow(2.0,expon+62.0));
		frexpf((float)inputSampleR, &expon);
		fpdR ^= fpdR << 13; fpdR ^= fpdR >> 17; fpdR ^= fpdR << 5;
		inputSampleR += double((double(fpdR)-uint32_t(0x7fffffff)) * 5.5e-36l * pow(2.0,expon+62.0));
		//end 32 bit stereo floating point dither

		*out1 = float(inputSampleL);
		*out2 = float(inputSampleR);

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

} // end namespace

#endif // SHR3D_SFX_CORE_AIRWINDOWS
