/***************************************************************************
 *   Copyright (C) 2008-2018 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 <QFile>
#include <QDir>
#include <QDirIterator>
#include <QSettings>
#include <QTextStream>
#include <QTextCodec>
#include <qmmp/decoder.h>
#include <qmmp/metadatamanager.h>
#ifdef WITH_ENCA
#include <enca.h>
#endif
#include "cueparser.h"

CUEParser::CUEParser(const QString &path)
{
    QString fileName = path;
    if(path.contains("://"))
    {
        fileName.remove("cue://");
        fileName.remove(QRegExp("#\\d+$"));
    }
    QFile file(fileName);
    if (!file.open(QIODevice::ReadOnly))
    {
        qDebug("CUEParser: error: %s", qPrintable(file.errorString()));
        return;
    }
    QTextStream textStream (&file);
    QSettings settings(Qmmp::configFile(), QSettings::IniFormat);
    settings.beginGroup("CUE");
    m_dirty = settings.value("dirty_cue", false).toBool();
    QTextCodec *codec = 0;
#ifdef WITH_ENCA
    EncaAnalyser analyser = 0;
    if(settings.value("use_enca", false).toBool())
    {
        analyser = enca_analyser_alloc(settings.value("enca_lang").toByteArray ().constData());

        if(analyser)
        {
            enca_set_threshold(analyser, 1.38);
            EncaEncoding encoding = enca_analyse(analyser,
                                                 (uchar *)file.readAll().constData(),
                                                 file.size());
            file.reset();
            if(encoding.charset != ENCA_CS_UNKNOWN)
            {
                codec = QTextCodec::codecForName(enca_charset_name(encoding.charset,ENCA_NAME_STYLE_ENCA));
                //qDebug("CUEParser: detected charset: %s",
                  //     enca_charset_name(encoding.charset,ENCA_NAME_STYLE_ENCA));
            }
        }
    }
#endif
    if(!codec)
        codec = QTextCodec::codecForName(settings.value("encoding","UTF-8").toByteArray ());
    if(!codec)
        codec = QTextCodec::codecForName("UTF-8");
    settings.endGroup();
    //qDebug("CUEParser: using %s encoding", codec->name().constData());
    textStream.setCodec(codec);
    QString album, genre, date, comment, artist, file_path;
    double album_gain = 0.0, album_peak = 0.0;

    while (!textStream.atEnd())
    {
        QString line = textStream.readLine().trimmed();
        QStringList words = splitLine(line);
        if (words.size() < 2)
            continue;

        if (words[0] == "FILE")
        {
            file_path = getDirtyPath(fileName, QFileInfo(fileName).dir().filePath(words[1]));
        }
        else if (words[0] == "PERFORMER")
        {
            if(m_tracks.isEmpty())
                artist = words[1];
            else
                m_tracks.last()->info.setValue(Qmmp::ARTIST, words[1]);
        }
        else if (words[0] == "TITLE")
        {
            if(m_tracks.isEmpty())
                album = words[1];
            else
                m_tracks.last()->info.setValue(Qmmp::TITLE, words[1]);
        }
        else if (words[0] == "TRACK")
        {
            QString path = fileName;
            TrackInfo info("cue://" + path + QString("#%1").arg(words[1].toInt()));
            info.setValue(Qmmp::TRACK, words[1].toInt());
            info.setValue(Qmmp::ALBUM, album);
            info.setValue(Qmmp::GENRE, genre);
            info.setValue(Qmmp::YEAR, date);
            info.setValue(Qmmp::COMMENT, comment);
            info.setValue(Qmmp::ARTIST, artist);
            info.setValue(Qmmp::ALBUMARTIST, artist);
            info.setValue(Qmmp::REPLAYGAIN_ALBUM_GAIN, album_gain);
            info.setValue(Qmmp::REPLAYGAIN_ALBUM_PEAK, album_peak);

            m_tracks << new CUETrack;
            m_tracks.last()->info = info;
            m_tracks.last()->offset = 0;
        }
        else if (words[0] == "INDEX" && words[1] == "01")
        {
            if (m_tracks.isEmpty())
                continue;
            m_tracks.last()->offset = getLength(words[2]);
            m_tracks.last()->file = file_path;
        }
        else if (words[0] == "REM")
        {
            if (words.size() < 3)
                continue;
            if (words[1] == "GENRE")
                genre = words[2];
            else if (words[1] == "DATE")
                date = words[2];
            else if (words[1] == "COMMENT")
                comment = words[2];
            else if (words[1] == "REPLAYGAIN_ALBUM_GAIN")
                album_gain = words[2].toDouble();
            else if (words[1] == "REPLAYGAIN_ALBUM_PEAK")
                album_peak = words[2].toDouble();
            else if (words[1] == "REPLAYGAIN_TRACK_GAIN" && !m_tracks.isEmpty())
                m_tracks.last()->info.setValue(Qmmp::REPLAYGAIN_TRACK_GAIN, words[2].toDouble());
            else if (words[1] == "REPLAYGAIN_TRACK_PEAK" && !m_tracks.isEmpty())
                m_tracks.last()->info.setValue(Qmmp::REPLAYGAIN_TRACK_PEAK, words[2].toDouble());
        }
    }
    file.close();
#ifdef WITH_ENCA
    if(analyser)
        enca_analyser_free(analyser);
#endif
    if(m_tracks.isEmpty())
    {
        qWarning("CUEParser: invalid cue file");
        return;
    }
    //skip invalid cue sheet
    foreach(CUETrack *track, m_tracks)
    {
        if(!QFile::exists(track->file))
        {
            qDeleteAll(m_tracks);
            m_tracks.clear();
            break;
        }
    }
    //calculate lengths
    QList<TrackInfo *> f_list;
    for(int i = 0; i < m_tracks.count(); ++i)
    {
        if(i == 0 || m_tracks[i - 1]->file != m_tracks[i]->file)
        {
            qDeleteAll(f_list);
            f_list = MetaDataManager::instance()->createPlayList(m_tracks[i]->file, TrackInfo::Properties);
        }
        if(!f_list.isEmpty())
            m_tracks[i]->info.setValues(f_list.first()->properties());

        if((i < m_tracks.count() - 1) && (m_tracks[i]->file == m_tracks[i+1]->file))
            m_tracks[i]->info.setDuration(m_tracks[i+1]->offset - m_tracks[i]->offset);
        else if(!f_list.isEmpty())
            m_tracks[i]->info.setDuration(qMax(0LL, f_list.first()->duration() - m_tracks[i]->offset));
    }
    qDeleteAll(f_list);
    f_list.clear();
}

CUEParser::~CUEParser()
{
    qDeleteAll(m_tracks);
    m_tracks.clear();
}

QList<TrackInfo *> CUEParser::createPlayList()
{
    QList<TrackInfo*> list;
    foreach(CUETrack *track, m_tracks)
    {
        list << new TrackInfo(track->info);
    }
    return list;
}

const QString CUEParser::filePath(int track) const
{
    return (track <= m_tracks.count()) ? m_tracks[track - 1]->file : QString();
}

const QStringList CUEParser::dataFiles() const
{
    QStringList files;
    for(int i = 0; i < m_tracks.count(); ++i)
    {
        if(i == 0)
        {
            files << m_tracks[i]->file;
            continue;
        }

        if(files.last() != m_tracks[i]->file)
            files.append(m_tracks[i]->file);
    }
    return files;
}

qint64 CUEParser::offset(int track) const
{
    return m_tracks.at(track - 1)->offset;
}

qint64 CUEParser::duration(int track) const
{
    return m_tracks.at(track - 1)->info.duration();
}

int CUEParser::count() const
{
    return m_tracks.count();
}

TrackInfo *CUEParser::info(int track)
{
    return &m_tracks.at(track - 1)->info;
}

const QString CUEParser::trackURL(int track) const
{
    return m_tracks.at(track - 1)->info.path();
}

const QMap<Qmmp::ReplayGainKey, double>  CUEParser::replayGain(int track) const
{
    return m_tracks.at(track - 1)->info.replayGainInfo();
}

QStringList CUEParser::splitLine(const QString &line)
{
    //qDebug("raw string = %s",qPrintable(line));
    QStringList list;
    QString buf = line.trimmed();
    if (buf.isEmpty())
        return list;
    while (!buf.isEmpty())
    {
        //qDebug(qPrintable(buf));
        if (buf.startsWith('"'))
        {
            int end = buf.indexOf('"',1);
            if(end == -1) //ignore invalid line
            {
                list.clear();
                qWarning("CUEParser: unable to parse line: %s",qPrintable(line));
                return list;
            }
            list << buf.mid (1, end - 1);
            buf.remove (0, end+1);
        }
        else
        {
            int end = buf.indexOf(' ', 0);
            if (end < 0)
                end = buf.size();
            list << buf.mid (0, end);
            buf.remove (0, end);
        }
        buf = buf.trimmed();
    }
    return list;
}

qint64 CUEParser::getLength(const QString &str)
{
    QStringList list = str.split(":");
    if (list.size() == 2)
        return (qint64)list.at(0).toInt()*60000 + list.at(1).toInt()*1000;
    else if (list.size() == 3)
        return (qint64)list.at(0).toInt()*60000 + list.at(1).toInt()*1000 + list.at(2).toInt()*1000/75;
    return 0;
}

QString CUEParser::getDirtyPath(const QString &cue_path, const QString &path)
{
    if((QFile::exists(path) && Decoder::findByFilePath(path)) || !m_dirty)
        return path;

    QStringList candidates;
    QDirIterator it(QFileInfo(path).dir().path(), QDir::Files);
    while (it.hasNext())
    {
        it.next();
        QString f = it.filePath();
        if ((f != cue_path) && Decoder::findByFilePath(f))
            candidates.push_back(f);
    }

    if (candidates.empty())
        return path;
    else if (candidates.count() == 1)
        return candidates.first();

    int dot = cue_path.lastIndexOf('.');
    if (dot != -1)
    {
        QRegExp r(QRegExp::escape(cue_path.left(dot)) + "\\.[^\\.]+$");

        int index = candidates.indexOf(r);
        int rindex = candidates.lastIndexOf(r);

        if ((index != -1) && (index == rindex))
            return candidates[index];
    }
    dot = path.lastIndexOf('.');
    if (dot != -1)
    {
        QRegExp r(QRegExp::escape(path.left(dot)) + "\\.[^\\.]+$");

        int index = candidates.indexOf(r);
        int rindex = candidates.lastIndexOf(r);

        if ((index != -1) && (index == rindex))
            return candidates[index];
    }

    return path;
}