// --------------------------------------------------------------
// main.cpp
// Test Application
// 08.03.2003
// --------------------------------------------------------------

#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
#include <math.h>
#include "radio.h"
#include "cmp.h"

// --------------------------------------------------------------
void cmp_init(cmp_t *pObj, long fs, double rms_sec, double lookahead_sec, double det_attack_sec, double det_release_sec, double vca_attack_sec, double vca_release_sec)
{
	pObj->rms_size = (long)(rms_sec*fs);
	pObj->dly_size = (long)(lookahead_sec*fs);
	if (pObj->dly_size <= 0)
		pObj->dly_size = 1;	
	pObj->fs = fs;
	pObj->vca_gain = 1;
	pObj->vca_gain_db = 0;
	pObj->vca_gain_target = 1;
	pObj->det_gain = 0;
	pObj->det_gain_db = 0;
	pObj->peak_mode = 0;
	pObj->det_ar = 4.0/(det_attack_sec*pObj->fs); 
	pObj->det_af = 4.0/(det_release_sec*pObj->fs); 
	pObj->det_br = 1 - pObj->det_ar;
	pObj->det_bf = 1 - pObj->det_af;
	pObj->vca_ar = 4.0/(vca_attack_sec*pObj->fs); 
	pObj->vca_af = 4.0/(vca_release_sec*pObj->fs); 
	pObj->vca_br = 1 - pObj->vca_ar;
	pObj->vca_bf = 1 - pObj->vca_af;
	SlidingVarInit(&pObj->var, pObj->rms_size, fs/20);
	RBufInit(&pObj->dly, pObj->dly_size);
}

double cmp_process(cmp_t *pObj, double xi, cmp_curve_t *pCurve, int curve_len, int mode)
{
	int k;
	double px, py, x, y;
	double x0, x1;
	double y0, y1;
	RBufPut(&pObj->dly, xi);
	x = RBufGetAfter(&pObj->dly, pObj->dly_size-1);
	px = sqrt(SlidingVarProcess(&pObj->var, xi));
	
	if (px > pObj->det_gain)
		pObj->det_gain = pObj->det_ar*px + pObj->det_br*pObj->det_gain;
	else
		pObj->det_gain = pObj->det_af*px + pObj->det_bf*pObj->det_gain;

	if (pObj->peak_mode)
		pObj->det_gain = fabs(x);

	pObj->det_gain_db = 20*log10(pObj->det_gain);
	
	k=0;
	while(k < (curve_len-1))
	{
		pObj->do_compress = 1;
		if (pObj->det_gain == 0)
		{
			pObj->vca_gain_target = 1;
			break;
		}

		if (pObj->det_gain_db <= pCurve[k+1].kth)
		{
			x0 = pCurve[k].kth;
			x1 = pCurve[k+1].kth;
			y0 = pCurve[k].kc;
			y1 = pCurve[k+1].kc;
			py = y0 + (pObj->det_gain_db - x0)*(y1-y0)/(x1-x0);
			pObj->vca_gain_target = pow(10, 0.05*py);
//			if (py > 0)
//				pObj->do_compress = 0;

			break;
		}
		else
		{
			k++;
		}
	}

	if (pObj->do_compress)
	{
		if (pObj->vca_gain > pObj->vca_gain_target)
			pObj->vca_gain = pObj->vca_ar*pObj->vca_gain_target + pObj->vca_br*pObj->vca_gain;
		else
			pObj->vca_gain = pObj->vca_af*pObj->vca_gain_target + pObj->vca_bf*pObj->vca_gain;
	}
	else
	{
		if (pObj->vca_gain < pObj->vca_gain_target)
			pObj->vca_gain = pObj->vca_ar*pObj->vca_gain_target + pObj->vca_br*pObj->vca_gain;
		else
			pObj->vca_gain = pObj->vca_af*pObj->vca_gain_target + pObj->vca_bf*pObj->vca_gain;
	}


	pObj->vca_gain_db = 20*log10(pObj->vca_gain);

	if (mode == 0)
		y = x;
	if (mode == 1)
	{
		if (pObj->peak_mode)
			y = 0.5*x*pObj->vca_gain_target;
		else
			y = x*pObj->vca_gain;
	}
	if (mode == 2)
		y = pObj->det_gain*sqrt(12.0)*(0.5-(double)rand()/RAND_MAX);
	if (mode == 3)
		y = 0.01*pObj->vca_gain_db;
	if (mode == 4)
		y = 0.01*(pObj->det_gain_db+pObj->vca_gain_db);

	return y;
}