/***************************************************************************
 *   Copyright (C) 1999 by Johan Levin                                     *
 *                                                                         *
 *   Copyright (C) 2011-2015 by Ilya Kotov                                 *
 *   forkotov02@ya.ru                                                      *
 *                                                                         *
 *   This program 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 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program 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 program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.         *
 ***************************************************************************/

#include <QSettings>
#include <math.h>
#include <stdlib.h>
#include <qmmp/qmmp.h>
#include "stereoplugin.h"

StereoPlugin *StereoPlugin::m_instance = 0;

StereoPlugin::StereoPlugin() : Effect()
{
    m_instance = this;
    m_avg = 0;
    m_ldiff = 0;
    m_rdiff = 0;
    m_tmp = 0;
    m_mul = 2.0;
    m_chan = 0;
    QSettings settings(Qmmp::configFile(), QSettings::IniFormat);
    m_mul = settings.value("extra_stereo/intensity", 1.0).toDouble();
}

StereoPlugin::~StereoPlugin()
{
    m_instance = 0;
}

void StereoPlugin::applyEffect(Buffer *b)
{
    if(m_chan != 2)
        return;

    m_mutex.lock();
    float *data = b->data;

    for (uint i = 0; i < b->samples; i += 2)
    {
        m_avg = (data[i] + data[i + 1]) / 2;
        m_ldiff = data[i] - m_avg;
        m_rdiff = data[i + 1] - m_avg;

        m_tmp = m_avg + m_ldiff * m_mul;
        data[i] = qBound(-1.0, m_tmp, 1.0);
        m_tmp = m_avg + m_rdiff * m_mul;
        data[i + 1] = qBound(-1.0, m_tmp, 1.0);
    }

    m_mutex.unlock();
}

void StereoPlugin::configure(quint32 freq, ChannelMap map)
{
    m_chan = map.count();
    Effect::configure(freq, map);
}

void StereoPlugin::setIntensity(double level)
{
    m_mutex.lock();
    m_mul = level;
    m_mutex.unlock();
}

StereoPlugin* StereoPlugin::instance()
{
    return m_instance;
}