/*
  Copyright (C) 2005 Benjamin Meyer <ben at meyerhome dot net>
  Copyright (C) 2018 Yuri Chornoivan <yurchor@mageia.org>

  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 <config-audiocd.h>

#include "audiocd_kio_debug.h"
#include "audiocd_opus_encoder.h"
#include "encoderopus.h"

#include <QDir>
#include <QFileInfo>
#include <QStandardPaths>
#include <QTemporaryFile>

Q_LOGGING_CATEGORY(AUDIOCD_KIO_LOG, "kf.kio.workers.audiocd")

extern "C" {
AUDIOCDPLUGINS_EXPORT void create_audiocd_encoders(KIO::WorkerBase *worker, QList<AudioCDEncoder *> &encoders)
{
    encoders.append(new EncoderOpus(worker));
}
}

static const int bitrates[] = {6, 12, 24, 48, 64, 80, 96, 128, 160, 192, 256};

class EncoderOpus::Private
{
public:
    int bitrate;
    bool write_opus_comments;
    bool waitingForWrite;
    bool processHasExited;
    QString lastErrorMessage;
    uint lastSize;
    KProcess *currentEncodeProcess = nullptr;
    QTemporaryFile *tempFile = nullptr;
};

EncoderOpus::EncoderOpus(KIO::WorkerBase *worker)
    : QObject()
    , AudioCDEncoder(worker)
{
    d = new Private();
    d->waitingForWrite = false;
    d->processHasExited = false;
    d->lastSize = 0;
    loadSettings();
}

EncoderOpus::~EncoderOpus()
{
    delete d;
}

QWidget *EncoderOpus::getConfigureWidget(KConfigSkeleton **manager) const
{
    (*manager) = Settings::self();
    auto config = new EncoderOpusConfig();
    config->kcfg_opus_complexity->setRange(0, 10);
    config->kcfg_opus_complexity->setSingleStep(1);
    config->opus_bitrate_settings->hide();
    return config;
}

bool EncoderOpus::init()
{
    // Determine if opusenc is installed on the system or not.
    if (QStandardPaths::findExecutable(QStringLiteral("opusenc")).isEmpty())
        return false;

    return true;
}

void EncoderOpus::loadSettings()
{
    // Generate the command line arguments for the current settings
    args.clear();

    Settings *settings = Settings::self();

    if (settings->opus_enc_complexity()) {
        args.append(QStringLiteral("--comp"));
        args.append(QStringLiteral("%1").arg(settings->opus_complexity()));
    } else {
        // Constant Bitrate Encoding
        if (settings->set_opus_cbr()) {
            args.append(QStringLiteral("--bitrate"));
            args.append(QStringLiteral("%1").arg(bitrates[settings->opus_cbr()]));
            d->bitrate = settings->opus_cbr();
            args.append(QStringLiteral("--hard-cbr"));
        };
        // Constrained Variable Bitrate Encoding
        if (settings->set_opus_cvbr()) {
            args.append(QStringLiteral("--bitrate"));
            args.append(QStringLiteral("%1").arg(bitrates[settings->opus_cvbr()]));
            d->bitrate = bitrates[settings->opus_cvbr()];
            args.append(QStringLiteral("--cvbr"));
        };
        // Average Variable Bitrate Encoding
        if (settings->set_opus_vbr()) {
            args.append(QStringLiteral("--bitrate"));
            args.append(QStringLiteral("%1").arg(bitrates[settings->opus_vbr()]));
            d->bitrate = bitrates[settings->opus_vbr()];
            args.append(QStringLiteral("--vbr"));
        };
    };

    d->write_opus_comments = settings->opus_comments();
}

unsigned long EncoderOpus::size(long time_secs) const {
    return (time_secs * d->bitrate * 1000) / 8;
}

long EncoderOpus::readInit(long /*size*/)
{
    // Create KProcess
    d->currentEncodeProcess = new KProcess();
    d->tempFile = new QTemporaryFile(QDir::tempPath() + QLatin1String("/kaudiocd_XXXXXX") + QLatin1String(".opus"));
    d->tempFile->open();
    d->lastErrorMessage.clear();
    d->processHasExited = false;

    // --raw raw/pcm
    // --raw-rate 44100 (because it is raw you have to specify this)
    *(d->currentEncodeProcess) << QStringLiteral("opusenc") << QStringLiteral("--raw") << QStringLiteral("--raw-rate") << QStringLiteral("44100");
    *(d->currentEncodeProcess) << args;
    *d->currentEncodeProcess << trackInfo;

    // Read in stdin, output to the temp file
    *d->currentEncodeProcess << QStringLiteral("-") << d->tempFile->fileName();

    // qCDebug(AUDIOCD_KIO_LOG) << args;

    connect(d->currentEncodeProcess, &KProcess::readyReadStandardOutput, this, &EncoderOpus::receivedStdout);
    connect(d->currentEncodeProcess, &KProcess::readyReadStandardError, this, &EncoderOpus::receivedStderr);
    connect(d->currentEncodeProcess, QOverload<int, QProcess::ExitStatus>::of(&KProcess::finished), this, &EncoderOpus::processExited);

    // Launch!
    d->currentEncodeProcess->setOutputChannelMode(KProcess::SeparateChannels);
    d->currentEncodeProcess->start();
    return 0;
}

void EncoderOpus::processExited(int exitCode, QProcess::ExitStatus /*status*/)
{
    qCDebug(AUDIOCD_KIO_LOG) << "Opusenc Encoding process exited with: " << exitCode;
    d->processHasExited = true;
}

void EncoderOpus::receivedStderr()
{
    QByteArray error = d->currentEncodeProcess->readAllStandardError();
    qCDebug(AUDIOCD_KIO_LOG) << "Opusenc stderr: " << error;
    if (!d->lastErrorMessage.isEmpty())
        d->lastErrorMessage += QLatin1Char('\t');
    d->lastErrorMessage += QString::fromLocal8Bit(error);
}

void EncoderOpus::receivedStdout()
{
    QString output = QString::fromLocal8Bit(d->currentEncodeProcess->readAllStandardOutput());
    qCDebug(AUDIOCD_KIO_LOG) << "Opusenc stdout: " << output;
}

long EncoderOpus::read(qint16 *buf, int frames)
{
    if (!d->currentEncodeProcess)
        return 0;
    if (d->processHasExited)
        return -1;

    // Pipe the raw data to opusenc
    char *cbuf = reinterpret_cast<char *>(buf);
    d->currentEncodeProcess->write(cbuf, frames * 4);
    // We can't return until the buffer has been written
    d->currentEncodeProcess->waitForBytesWritten(-1);

    // Determine the file size increase
    QFileInfo file(d->tempFile->fileName());
    uint change = file.size() - d->lastSize;
    d->lastSize = file.size();
    return change;
}

long EncoderOpus::readCleanup()
{
    if (!d->currentEncodeProcess)
        return 0;

    // Let opusenc tag the first frame of the opus
    d->currentEncodeProcess->closeWriteChannel();
    d->currentEncodeProcess->waitForFinished(-1);

    // Now copy the file out of the temp into kio
    QFile file(d->tempFile->fileName());
    if (file.open(QIODevice::ReadOnly)) {
        char data[1024];
        while (!file.atEnd()) {
            uint read = file.read(data, 1024);
            QByteArray output(data, read);
            ioWorker->data(output);
        }
        file.close();
    }

    // cleanup the process and temp
    delete d->currentEncodeProcess;
    delete d->tempFile;
    d->lastSize = 0;

    return 0;
}

void EncoderOpus::fillSongInfo(KCDDB::CDInfo info, int track, const QString &comment)
{
    trackInfo.clear();

    if (!d->write_opus_comments)
        return;

    trackInfo.append(QStringLiteral("--album"));
    trackInfo.append(info.get(Title).toString());

    trackInfo.append(QStringLiteral("--artist"));
    trackInfo.append(info.track(track - 1).get(Artist).toString());

    trackInfo.append(QStringLiteral("--title"));
    trackInfo.append(info.track(track - 1).get(Title).toString());

    trackInfo.append(QStringLiteral("--date"));
    trackInfo.append(QDate(info.get(Year).toInt(), 1, 1).toString(Qt::ISODate));

    trackInfo.append(QStringLiteral("--comment"));
    trackInfo.append(QStringLiteral("DESCRIPTION=") + comment);

    trackInfo.append(QStringLiteral("--comment"));
    trackInfo.append(QStringLiteral("TRACKNUMBER=") + QString::number(track));

    trackInfo.append(QStringLiteral("--genre"));
    trackInfo.append(QStringLiteral("%1").arg(info.get(Genre).toString()));
}

QString EncoderOpus::lastErrorMessage() const
{
    return d->lastErrorMessage;
}
