/* ========================================
 *  Srsly2 - Srsly2.h
 *  Copyright (c) 2016 airwindows, Airwindows uses the MIT license
 * ======================================== */

#include "Srsly2.h"

#ifdef SHR3D_SFX_CORE_AIRWINDOWS

namespace airwinconsolidated::Srsly2 {

void Srsly2::processBlock(float **inputs, float **outputs, int sampleFrames) 
{
    float* in1  =  inputs[0];
    float* in2  =  inputs[1];
    float* out1 = outputs[0];
    float* out2 = outputs[1];

	double sampleRate = getSampleRate();
	if (sampleRate < 22000) sampleRate = 22000; //keep biquads in range
	double tempSample;
	
	biquadM2[0] = 2000 / sampleRate; //up
	biquadM7[0] = 7000 / sampleRate; //down
	biquadM10[0] = 10000 / sampleRate; //down
	
	biquadL3[0] = 3000 / sampleRate; //up
	biquadL7[0] = 7000 / sampleRate; //way up
	biquadR3[0] = 3000 / sampleRate; //up
	biquadR7[0] = 7000 / sampleRate; //way up
	
	biquadS3[0] = 3000 / sampleRate; //up
	biquadS5[0] = 5000 / sampleRate; //way down
	
	double focusM = 15.0-(A*10.0);
	double focusS = 21.0-(B*15.0);
	double Q = D+0.25; //add Q control: from half to double intensity
	double gainM = A*2.0;
	double gainS = B*2.0;
	if (gainS > 1.0) gainM /= gainS;
	if (gainM > 1.0) gainM = 1.0;
	
	biquadM2[1] = focusM*0.25*Q; //Q, mid 2K boost is much broader
    biquadM7[1] = focusM*Q; //Q
    biquadM10[1] = focusM*Q; //Q
    biquadS3[1] = focusM*Q; //Q
    biquadS5[1] = focusM*Q; //Q
	
    biquadL3[1] = focusS*Q; //Q
    biquadL7[1] = focusS*Q; //Q
    biquadR3[1] = focusS*Q; //Q
    biquadR7[1] = focusS*Q; //Q
	
	double K = tan(M_PI * biquadM2[0]);
	double norm = 1.0 / (1.0 + K / biquadM2[1] + K * K);
	biquadM2[2] = K / biquadM2[1] * norm;
	biquadM2[4] = -biquadM2[2];
	biquadM2[5] = 2.0 * (K * K - 1.0) * norm;
	biquadM2[6] = (1.0 - K / biquadM2[1] + K * K) * norm;
	
	K = tan(M_PI * biquadM7[0]);
	norm = 1.0 / (1.0 + K / biquadM7[1] + K * K);
	biquadM7[2] = K / biquadM7[1] * norm;
	biquadM7[4] = -biquadM7[2];
	biquadM7[5] = 2.0 * (K * K - 1.0) * norm;
	biquadM7[6] = (1.0 - K / biquadM7[1] + K * K) * norm;
	
	K = tan(M_PI * biquadM10[0]);
	norm = 1.0 / (1.0 + K / biquadM10[1] + K * K);
	biquadM10[2] = K / biquadM10[1] * norm;
	biquadM10[4] = -biquadM10[2];
	biquadM10[5] = 2.0 * (K * K - 1.0) * norm;
	biquadM10[6] = (1.0 - K / biquadM10[1] + K * K) * norm;
	
	K = tan(M_PI * biquadL3[0]);
	norm = 1.0 / (1.0 + K / biquadL3[1] + K * K);
	biquadL3[2] = K / biquadL3[1] * norm;
	biquadL3[4] = -biquadL3[2];
	biquadL3[5] = 2.0 * (K * K - 1.0) * norm;
	biquadL3[6] = (1.0 - K / biquadL3[1] + K * K) * norm;
	
	K = tan(M_PI * biquadL7[0]);
	norm = 1.0 / (1.0 + K / biquadL7[1] + K * K);
	biquadL7[2] = K / biquadL7[1] * norm;
	biquadL7[4] = -biquadL7[2];
	biquadL7[5] = 2.0 * (K * K - 1.0) * norm;
	biquadL7[6] = (1.0 - K / biquadL7[1] + K * K) * norm;
	
	K = tan(M_PI * biquadR3[0]);
	norm = 1.0 / (1.0 + K / biquadR3[1] + K * K);
	biquadR3[2] = K / biquadR3[1] * norm;
	biquadR3[4] = -biquadR3[2];
	biquadR3[5] = 2.0 * (K * K - 1.0) * norm;
	biquadR3[6] = (1.0 - K / biquadR3[1] + K * K) * norm;
	
	K = tan(M_PI * biquadR7[0]);
	norm = 1.0 / (1.0 + K / biquadR7[1] + K * K);
	biquadR7[2] = K / biquadR7[1] * norm;
	biquadR7[4] = -biquadR7[2];
	biquadR7[5] = 2.0 * (K * K - 1.0) * norm;
	biquadR7[6] = (1.0 - K / biquadR7[1] + K * K) * norm;
	
	K = tan(M_PI * biquadS3[0]);
	norm = 1.0 / (1.0 + K / biquadS3[1] + K * K);
	biquadS3[2] = K / biquadS3[1] * norm;
	biquadS3[4] = -biquadS3[2];
	biquadS3[5] = 2.0 * (K * K - 1.0) * norm;
	biquadS3[6] = (1.0 - K / biquadS3[1] + K * K) * norm;
	
	K = tan(M_PI * biquadS5[0]);
	norm = 1.0 / (1.0 + K / biquadS5[1] + K * K);
	biquadS5[2] = K / biquadS5[1] * norm;
	biquadS5[4] = -biquadS5[2];
	biquadS5[5] = 2.0 * (K * K - 1.0) * norm;
	biquadS5[6] = (1.0 - K / biquadS5[1] + K * K) * norm;
	
	double depthM = pow(A,2)*2.0;; //proportion to mix in the filtered stuff
	double depthS = pow(B,2)*2.0;; //proportion to mix in the filtered stuff
	double level = C; //output pad
	double wet = E; //dry/wet
	
	//biquad contains these values:
	//[0] is frequency: 0.000001 to 0.499999 is near-zero to near-Nyquist
	//[1] is resonance, 0.7071 is Butterworth. Also can't be zero
	//[2] is a0 but you need distinct ones for additional biquad instances so it's here
	//[3] is a1 but you need distinct ones for additional biquad instances so it's here
	//[4] is a2 but you need distinct ones for additional biquad instances so it's here
	//[5] is b1 but you need distinct ones for additional biquad instances so it's here
	//[6] is b2 but you need distinct ones for additional biquad instances so it's here
	//[7] is LEFT stored delayed sample (freq and res are stored so you can move them sample by sample)
	//[8] is LEFT stored delayed sample (you have to include the coefficient making code if you do that)
	//[9] is RIGHT stored delayed sample (freq and res are stored so you can move them sample by sample)
	//[10] is RIGHT stored delayed sample (you have to include the coefficient making code if you do that)
	
    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;
		
		inputSampleL = sin(inputSampleL);
		inputSampleR = sin(inputSampleR);
		//encode Console5: good cleanness
		
		double mid = inputSampleL + inputSampleR;
		double rawmid = mid * 0.5; //we'll use this to isolate L&R a little
		double side = inputSampleL - inputSampleR;
		double boostside = side * depthS;
		//assign mid and side.Between these sections, you can do mid/side processing
		
		tempSample = (mid * biquadM2[2]) + biquadM2[7];
		biquadM2[7] = (-tempSample * biquadM2[5]) + biquadM2[8];
		biquadM2[8] = (mid * biquadM2[4]) - (tempSample * biquadM2[6]);
		double M2Sample = tempSample; //like mono AU, 7 and 8 store L channel
		
		tempSample = (mid * biquadM7[2]) + biquadM7[7];
		biquadM7[7] = (-tempSample * biquadM7[5]) + biquadM7[8];
		biquadM7[8] = (mid * biquadM7[4]) - (tempSample * biquadM7[6]);
		double M7Sample = -tempSample*2.0; //like mono AU, 7 and 8 store L channel
		
		tempSample = (mid * biquadM10[2]) + biquadM10[7];
		biquadM10[7] = (-tempSample * biquadM10[5]) + biquadM10[8];
		biquadM10[8] = (mid * biquadM10[4]) - (tempSample * biquadM10[6]);
		double M10Sample = -tempSample*2.0; //like mono AU, 7 and 8 store L channel
		//mid
		
		tempSample = (side * biquadS3[2]) + biquadS3[7];
		biquadS3[7] = (-tempSample * biquadS3[5]) + biquadS3[8];
		biquadS3[8] = (side * biquadS3[4]) - (tempSample * biquadS3[6]);
		double S3Sample = tempSample*2.0; //like mono AU, 7 and 8 store L channel
		
		tempSample = (side * biquadS5[2]) + biquadS5[7];
		biquadS5[7] = (-tempSample * biquadS5[5]) + biquadS5[8];
		biquadS5[8] = (side * biquadS5[4]) - (tempSample * biquadS5[6]);
		double S5Sample = -tempSample*5.0; //like mono AU, 7 and 8 store L channel
		
		mid = (M2Sample + M7Sample + M10Sample)*depthM;
		side = (S3Sample + S5Sample + boostside)*depthS;
		
		double msOutSampleL = (mid+side)/2.0;
		double msOutSampleR = (mid-side)/2.0;
		//unassign mid and side
		
		double isoSampleL = inputSampleL-rawmid;
		double isoSampleR = inputSampleR-rawmid; //trying to isolate L and R a little
		
		tempSample = (isoSampleL * biquadL3[2]) + biquadL3[7];
		biquadL3[7] = (-tempSample * biquadL3[5]) + biquadL3[8];
		biquadL3[8] = (isoSampleL * biquadL3[4]) - (tempSample * biquadL3[6]);
		double L3Sample = tempSample; //like mono AU, 7 and 8 store L channel
		
		tempSample = (isoSampleR * biquadR3[2]) + biquadR3[9];
		biquadR3[9] = (-tempSample * biquadR3[5]) + biquadR3[10];
		biquadR3[10] = (isoSampleR * biquadR3[4]) - (tempSample * biquadR3[6]);
		double R3Sample = tempSample; //note: 9 and 10 store the R channel
		
		tempSample = (isoSampleL * biquadL7[2]) + biquadL7[7];
		biquadL7[7] = (-tempSample * biquadL7[5]) + biquadL7[8];
		biquadL7[8] = (isoSampleL * biquadL7[4]) - (tempSample * biquadL7[6]);
		double L7Sample = tempSample*3.0; //like mono AU, 7 and 8 store L channel
		
		tempSample = (isoSampleR * biquadR7[2]) + biquadR7[9];
		biquadR7[9] = (-tempSample * biquadR7[5]) + biquadR7[10];
		biquadR7[10] = (isoSampleR * biquadR7[4]) - (tempSample * biquadR7[6]);
		double R7Sample = tempSample*3.0; //note: 9 and 10 store the R channel
		
		double processingL = msOutSampleL + ((L3Sample + L7Sample)*depthS);
		double processingR = msOutSampleR + ((R3Sample + R7Sample)*depthS);
		//done with making filters, now we apply them
		
		mid = inputSampleL + inputSampleR;
		side = inputSampleL - inputSampleR;
		//re-assign mid and side.Between these sections, you can do mid/side processing
		
		mid *= gainM;
		side *= gainS;
		//we crank things up more than a bit, or cut them in line with how the hardware box works
		if (side > 1.57079633) side = 1.57079633;
		if (side < -1.57079633) side = -1.57079633;
		side = sin(side);
		side *= gainS;
		
		
		inputSampleL = ((mid+side)/2.0)+processingL;
		inputSampleR = ((mid-side)/2.0)+processingR;
		//unassign mid and side
		
		if (level < 1.0) {
			inputSampleL *= level;
			inputSampleR *= level;
		}
		
		if (inputSampleL > 1.0) inputSampleL = 1.0;
		if (inputSampleL < -1.0) inputSampleL = -1.0;
		if (inputSampleR > 1.0) inputSampleR = 1.0;
		if (inputSampleR < -1.0) inputSampleR = -1.0;
		//without this, you can get a NaN condition where it spits out DC offset at full blast!
		inputSampleL = asin(inputSampleL);
		inputSampleR = asin(inputSampleR);
		//amplitude aspect
		
		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
