#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <gnome.h>
#include "stereo.h"

void stereo_init(struct _stereo *stereo)
{

	memset(stereo,0,sizeof(struct _stereo));
	    
	/* read from config file ... if fail, set default */
	gnome_config_push_prefix("/liteamp/stereo/");

	stereo->on = gnome_config_get_bool("on=FALSE");
	stereo->level = gnome_config_get_float("level=2.0");
					    
	gnome_config_pop_prefix();
}

void stereo_quit()
{

}

void stereo_apply_change(struct _stereo *stereo)
{
	/* get value from widget and write config file */
	stereo->on = gtk_toggle_button_get_active(GTK_TOGGLE_BUTTON(stereo->chk));
  	stereo->level = gtk_range_get_value(GTK_RANGE(stereo->hs_stereo_level));
	
	gnome_config_push_prefix("/liteamp/stereo/");

	gnome_config_set_bool("on",stereo->on);
	gnome_config_set_float("level",stereo->level);
					    
	gnome_config_pop_prefix();
}

gint stereo_play_it(gint16 **d, gint length,struct _stereo *stereo,gint nch,gint samplerate,gint bitrate)
{
	gint i;
	gfloat value = stereo->level;
	gdouble avg, ldiff, rdiff, tmp, mul;
	gint16  *data = (gint16 *)*d;

	mul = value;
	
	for (i = 0; i < length / 2; i += 2)
	{
		avg = (data[i] + data[i + 1]) / 2;
		ldiff = data[i] - avg;
		rdiff = data[i + 1] - avg;

		tmp = avg + ldiff * mul;
		if (tmp < -32768)
			tmp = -32768;
		if (tmp > 32767)
			tmp = 32767;
		data[i] = tmp;

		tmp = avg + rdiff * mul;
		if (tmp < -32768)
			tmp = -32768;
		if (tmp > 32767)
			tmp = 32767;
		data[i + 1] = tmp;
	}
	return length;
}