/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
 *            chresampler.cc
 *
 *  Tue Sep 23 20:42:14 CEST 2014
 *  Copyright 2014 Bent Bisballe Nyeng
 *  deva@aasimon.org
 ****************************************************************************/

/*
 *  This file is part of DrumGizmo.
 *
 *  DrumGizmo is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU Lesser General Public License as published by
 *  the Free Software Foundation; either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  DrumGizmo 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 Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with DrumGizmo; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
 */
#include "chresampler.h"
#include "cpp11fix.h"

#include <config.h>
#include <hugin.hpp>
#include <stdio.h>

#ifdef WITH_RESAMPLER

#if defined(USE_ZITA)
#include <zita-resampler/resampler.h>
#elif defined(USE_SRC)
#include <samplerate.h>
#else
#error "No resampler selected"
#endif

class CHResampler::Prv
{
public:
#if defined(USE_ZITA)
	Resampler zita;
#elif defined(USE_SRC)
	SRC_STATE* state;
	SRC_DATA data;
#endif
};

CHResampler::CHResampler()
    : prv{std::make_unique<Prv>()}
    , input_fs{44100}
    , output_fs{44100}
{
#if defined(SRC)
	prv->state = nullptr;
#endif
}

void CHResampler::setup(double input_fs, double output_fs)
{
	int nchan = 1; // always mono

	this->input_fs = input_fs;
	this->output_fs = output_fs;

#if defined(USE_ZITA)
	DEBUG(resampler, "Using zita-resampler (%d -> %d)", (int)input_fs,
	    (int)output_fs);

	int hlen = 72; // 16 ≤ hlen ≤ 96
	// delay is 2 * hlen, 72 corresponds to delay introduced by SRC.
	prv->zita.setup(input_fs, output_fs, nchan, hlen);
#elif defined(USE_SRC)
	DEBUG(resampler, "Using libsamplerate (%d -> %d)", (int)input_fs,
	    (int)output_fs);

	int err;
	prv->state = src_new(SRC_SINC_BEST_QUALITY, nchan, &err);
	(void)err;
	//  printf("err: %d\n", err);
	src_set_ratio(prv->state, output_fs / input_fs);
	prv->data.src_ratio = output_fs / input_fs;
	prv->data.end_of_input = 0;
#endif
}

CHResampler::~CHResampler()
{
#if defined(USE_ZITA)
#elif defined(USE_SRC)
	if(prv->state)
	{
		src_delete(prv->state);
	}
#endif
}

void CHResampler::setInputSamples(float* samples, size_t count)
{
#if defined(USE_ZITA)
	prv->zita.inp_data = samples;
	prv->zita.inp_count = count;
#elif defined(USE_SRC)
	prv->data.data_in = samples;
	prv->data.input_frames = count;
#endif
}

void CHResampler::setOutputSamples(float* samples, size_t count)
{
#if defined(USE_ZITA)
	prv->zita.out_data = samples;
	prv->zita.out_count = count;
#elif defined(USE_SRC)
	prv->data.data_out = samples;
	prv->data.output_frames = count;
#endif
}

void CHResampler::process()
{
#if defined(USE_ZITA)
	prv->zita.process();
#elif defined(USE_SRC)
	src_process(prv->state, &prv->data);
	prv->data.output_frames -= prv->data.output_frames_gen;
	prv->data.data_out += prv->data.output_frames_gen;
	prv->data.input_frames -= prv->data.input_frames_used;
	prv->data.data_in += prv->data.input_frames_used;
#endif
}

size_t CHResampler::getInputSampleCount() const
{
#if defined(USE_ZITA)
	return prv->zita.inp_count;
#elif defined(USE_SRC)
	return prv->data.input_frames;
#endif
}

size_t CHResampler::getOutputSampleCount() const
{
#if defined(USE_ZITA)
	return prv->zita.out_count;
#elif defined(USE_SRC)
	return prv->data.output_frames;
#endif
}

double CHResampler::getRatio() const
{
	return input_fs / output_fs;
}

#else

// Dummy implementation
CHResampler::CHResampler() {} 
CHResampler::~CHResampler() {}
void CHResampler::setup(double, double) {}
void CHResampler::setInputSamples(float*, size_t) {}
void CHResampler::setOutputSamples(float*, size_t) {}
void CHResampler::process() {}

size_t CHResampler::getInputSampleCount() const
{
	return 0;
}

size_t CHResampler::getOutputSampleCount() const
{
	return 0;
}

double CHResampler::getRatio() const
{
	return 1;
}

#endif /*WITH_RESAMPLER*/