/***************************************************************************
 *   Copyright (C) 2006-2024 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 <QObject>
#include <QIODevice>
#include <QtGlobal>
#include <qmmp/buffer.h>
#include <qmmp/output.h>
#include "decoder_aac.h"
#include "aacfile.h"

#define AAC_BUFFER_SIZE 4096

// Decoder class

DecoderAAC::DecoderAAC(QIODevice *i) : Decoder(i)
{}

DecoderAAC::~DecoderAAC()
{
    if(data())
    {
        if(data()->handle)
            NeAACDecClose (data()->handle);
        delete data();
        m_data = nullptr;
    }

    delete [] m_input_buf;
    m_input_buf = nullptr;
    m_bitrate = 0;
}

bool DecoderAAC::initialize()
{
    m_bitrate = 0;
    m_totalTime = 0;

    if(!input())
    {
        qCWarning(plugin, "cannot initialize.  No input.");
        return false;
    }
    if(!m_input_buf)
        m_input_buf = new char[AAC_BUFFER_SIZE];
    m_input_at = 0;

    AACFile aac_file(input());
    if(!aac_file.isValid())
    {
        qCWarning(plugin, "unsupported AAC file");
        return false;
    }

    //skip id3 tag and partial frame
    if(aac_file.offset() > 0)
    {
        qCDebug(plugin, "header offset = %d bytes", aac_file.offset());

        char *data = new char[aac_file.offset()];
        input()->read(data, aac_file.offset());
        delete [] data;
    }

    m_totalTime = aac_file.duration();
    m_bitrate = aac_file.bitrate();

    if(!m_data)
        m_data = new aac_data;

    data()->handle = NeAACDecOpen();

    NeAACDecConfigurationPtr conf;
    conf = NeAACDecGetCurrentConfiguration(data()->handle);
    conf->downMatrix = 1;
    conf->defSampleRate = 44100;
    conf->dontUpSampleImplicitSBR = 0;
    conf->defObjectType = LC;
    conf->outputFormat = FAAD_FMT_16BIT;
    NeAACDecSetConfiguration(data()->handle, conf);

    m_input_at = input()->read((char *)m_input_buf, AAC_BUFFER_SIZE);
    unsigned long freq = 0;
    unsigned char chan = 0;
    int res = NeAACDecInit(data()->handle, (unsigned char*) m_input_buf, m_input_at, &freq, &chan);

    if(res < 0)
    {
        qCWarning(plugin, "NeAACDecInit() failed");
        return false;
    }
    if(!freq || !chan)
    {
        qCWarning(plugin, "invalid sound parameters");
        return false;
    }

    memmove(m_input_buf, m_input_buf + res, m_input_at - res);
    m_input_at -= res;
    setProperty(Qmmp::FORMAT_NAME, u"AAC"_s);
    configure(freq, chan, Qmmp::PCM_S16LE);
    qCDebug(plugin, "initialize succes");
    return true;
}

qint64 DecoderAAC::read(unsigned char *audio, qint64 maxSize)
{
    NeAACDecFrameInfo frame_info;
    qint64 size = 0, to_read, read;
    bool eof = false;

    while(m_sample_buf_size <= 0 && !eof)
    {
        m_sample_buf_at = 0;
        if(m_input_at < AAC_BUFFER_SIZE)
        {
            to_read = AAC_BUFFER_SIZE - m_input_at;
            read = input()->read((char *) (m_input_buf + m_input_at),  to_read);
            eof = (read != to_read);
            m_input_at += read;
        }

        if(m_input_at == 0)
            return 0;

        m_sample_buf = NeAACDecDecode(data()->handle, &frame_info, (uchar *)m_input_buf, m_input_at);
        memmove(m_input_buf, m_input_buf + frame_info.bytesconsumed,
                m_input_at - frame_info.bytesconsumed);

        m_input_at -= frame_info.bytesconsumed;

        if(eof && frame_info.error > 0) //ignore error on end of file
            return 0;

        if(frame_info.error > 0)
        {
            m_input_at = 0;
            qCDebug(plugin) << NeAACDecGetErrorMessage(frame_info.error);
            return -1;
        }
        if(frame_info.samples > 0)
            m_bitrate = frame_info.bytesconsumed * 8 * frame_info.samplerate * frame_info.channels
                    / frame_info.samples / 1000;

        m_sample_buf_size = frame_info.samples * 2;
    }

    if(m_sample_buf_size > 0)
    {
        size = qMin(m_sample_buf_size, maxSize);
        memcpy(audio, (char *)(m_sample_buf) + m_sample_buf_at, size);
        m_sample_buf_at += size;
        m_sample_buf_size -= size;
    }

    return size;
}

qint64 DecoderAAC::totalTime() const
{
    return m_totalTime;
}

int DecoderAAC::bitrate() const
{
    return m_bitrate;
}

void DecoderAAC::seek(qint64 pos)
{
    input()->seek(pos * input()->size() / m_totalTime);
    NeAACDecPostSeekReset (data()->handle, 0);
    m_input_at = 0;
}
