/*
  An LV2 plugin to calculate the ratio of two signals.
  Copyright 2011 David Robillard
  Copyright 2004 Mike Rawes

  This is free software: you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  This software is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this software.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <stdlib.h>
#include "lv2/lv2plug.in/ns/lv2core/lv2.h"
#include "math_func.h"
#include "common.h"

#define RATIO_NUMERATOR   0
#define RATIO_DENOMINATOR 1
#define RATIO_OUTPUT      2

typedef struct {
	float* numerator;
	float* denominator;
	float* output;
} Ratio;

static void
cleanup(LV2_Handle instance)
{
	free(instance);
}

static void
connect_port(LV2_Handle instance,
             uint32_t   port,
             void*      data)
{
	Ratio* plugin = (Ratio*)instance;

	switch (port) {
	case RATIO_NUMERATOR:
		plugin->numerator = data;
		break;
	case RATIO_DENOMINATOR:
		plugin->denominator = data;
		break;
	case RATIO_OUTPUT:
		plugin->output = data;
		break;
	}
}

static LV2_Handle
instantiate(const LV2_Descriptor*     descriptor,
            double                    sample_rate,
            const char*               bundle_path,
            const LV2_Feature* const* features)
{
	Ratio* plugin = (Ratio*)malloc(sizeof(Ratio));

	return (LV2_Handle)plugin;
}

static void
runRatio_nada_oa(LV2_Handle instance,
                 uint32_t   sample_count)
{
	Ratio* plugin = (Ratio*)instance;

	/* Numerator (array of floats of length sample_count) */
	const float* numerator = plugin->numerator;

	/* Denominator (array of floats of length sample_count) */
	float* denominator = plugin->denominator;

	/* Output (array of floats of length sample_count) */
	float* output = plugin->output;

	float n;
	float d;

	for (uint32_t s = 0; s < sample_count; ++s) {
		n = numerator[s];
		d = denominator[s];

		d = COPYSIGNF(f_max(FABSF(d), 1e-16f), d);

		output[s] = n / d;
	}
}

static void
runRatio_nadc_oa(LV2_Handle instance,
                 uint32_t   sample_count)
{
	Ratio* plugin = (Ratio*)instance;

	/* Numerator (array of floats of length sample_count) */
	const float* numerator = plugin->numerator;

	/* Denominator (float value) */
	float denominator = *(plugin->denominator);

	/* Output (array of floats of length sample_count) */
	float* output = plugin->output;

	float n;

	denominator = COPYSIGNF(f_max(FABSF(denominator), 1e-16f), denominator);

	for (uint32_t s = 0; s < sample_count; ++s) {
		n = numerator[s];

		output[s] = n / denominator;
	}
}

static void
runRatio_ncda_oa(LV2_Handle instance,
                 uint32_t   sample_count)
{
	Ratio* plugin = (Ratio*)instance;

	/* Numerator (float value) */
	const float numerator = *(plugin->numerator);

	/* Denominator (array of floats of length sample_count) */
	const float* denominator = plugin->denominator;

	/* Output (array of floats of length sample_count) */
	float* output = plugin->output;

	float d;

	for (uint32_t s = 0; s < sample_count; ++s) {
		d = denominator[s];
		d = COPYSIGNF(f_max(FABSF(d), 1e-16f), d);

		output[s] = numerator / d;
	}
}

static void
runRatio_ncdc_oc(LV2_Handle instance,
                 uint32_t   sample_count)
{
	Ratio* plugin = (Ratio*)instance;

	/* Numerator (float value) */
	const float numerator = *(plugin->numerator);

	/* Denominator (float value) */
	float denominator = *(plugin->denominator);

	/* Output Frequency (pointer to float value) */
	float* output = plugin->output;

	denominator = COPYSIGNF(f_max(FABSF(denominator), 1e-16f), denominator);

	output[0] = numerator / denominator;
}

static const LV2_Descriptor descriptor = {
	"http://drobilla.net/plugins/blip/ratio",
	instantiate,
	connect_port,
	NULL,
	runRatio_nada_oa,
	NULL,
	cleanup,
	NULL,
};

LV2_SYMBOL_EXPORT const LV2_Descriptor*
lv2_descriptor(uint32_t index)
{
	switch (index) {
	case 0:  return &descriptor;
	default: return NULL;
	}
}