/***************************************************************************
 *   Copyright(C) 2006-2021 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 <QTextStream>
#include <algorithm>
#include <time.h>
#include <qmmp/metadatamanager.h>
#include "metadatahelper_p.h"
#include "playlistparser.h"
#include "playlistformat.h"
#include "playlistcontainer_p.h"
#include "groupedcontainer_p.h"
#include "normalcontainer_p.h"
#include "playlisttask_p.h"
#include "fileloader_p.h"
#include "playstate_p.h"
#include "detailsdialog.h"
#include "qmmpuisettings.h"
#include "playlistmodel.h"

#define INVALID_INDEX -1

PlayListModel::PlayListModel(const QString &name, QObject *parent)
    : QObject(parent) , m_name(name)
{
    qsrand(time(nullptr));
    m_ui_settings = QmmpUiSettings::instance();

    m_loader = new FileLoader(this);
    m_task = new PlayListTask(this);
    if(m_ui_settings->isGroupsEnabled())
        m_container = new GroupedContainer;
    else
        m_container = new NormalContainer;
    if(m_ui_settings->isShuffle())
        m_play_state = new ShufflePlayState(this);
    else
        m_play_state = new NormalPlayState(this);
    connect(m_ui_settings, SIGNAL(groupsChanged(bool)), SLOT(prepareGroups(bool)));
    connect(m_ui_settings, SIGNAL(shuffleChanged(bool)), SLOT(prepareForShufflePlaying(bool)));
    connect(m_loader, SIGNAL(newTracksToInsert(PlayListItem*, QList<PlayListTrack*>)),
            SLOT(insert(PlayListItem*, QList<PlayListTrack*>)), Qt::QueuedConnection);
    connect(m_loader, SIGNAL(finished()), SLOT(preparePlayState()));
    connect(m_loader, SIGNAL(finished()), SIGNAL(loaderFinished()));
    connect(m_task, SIGNAL(finished()), SLOT(onTaskFinished()));
}

PlayListModel::~PlayListModel()
{
    blockSignals(true);
    m_loader->finish();
    clear();
    delete m_play_state;
    delete m_container;
}

QString PlayListModel::name() const
{
    return m_name;
}

void PlayListModel::setName(const QString &name)
{
    if(m_name != name)
    {
        m_name = name;
        emit nameChanged(name);
    }
}

void PlayListModel::add(PlayListTrack *track)
{
    m_container->addTrack(track);
    m_total_duration += track->duration();
    int flags = 0;

    if(m_container->trackCount() == 1)
    {
        m_current_track = track;
        m_current = m_container->indexOf(track);
        flags |= CURRENT;
    }
    else if(m_ui_settings->isGroupsEnabled())
    {
        //update current index for grouped container only
        m_current = m_container->indexOf(m_current_track);
    }
    flags |= STRUCTURE;
    emit listChanged(flags);
}

void PlayListModel::add(const QList<PlayListTrack *> &tracks)
{
    if(tracks.isEmpty())
        return;

    int flags = 0;

    m_container->addTracks(tracks);

    if(m_container->trackCount() == tracks.count())
    {
        m_current_track = tracks.first();
        m_current = m_container->indexOf(m_current_track);
        flags |= CURRENT;
    }
    else if(m_ui_settings->isGroupsEnabled())
    {
        //update current index for grouped container only
        m_current = m_container->indexOf(m_current_track);
    }

    for(PlayListTrack *track : qAsConst(tracks))
    {
        m_total_duration += track->duration();
        emit trackAdded(track);
    }
    preparePlayState();
    flags |= STRUCTURE;
    emit listChanged(flags);
}

void PlayListModel::add(const QString &path)
{
    m_loader->add(path);
}

void PlayListModel::add(const QStringList &paths)
{
    m_loader->add(paths);
}

void PlayListModel::insert(int index, PlayListTrack *track)
{
    m_container->insertTrack(index, track);
    m_total_duration += track->duration();

    int flags = 0;

    if(m_container->trackCount() == 1)
    {
        m_current_track = track;
        m_current = m_container->indexOf(track);
        flags |= CURRENT;
    }
    else
    {
        //update current index
        m_current = m_container->indexOf(m_current_track);
    }
    emit trackAdded(track);
    flags |= STRUCTURE;
    emit listChanged(flags);
}

void PlayListModel::insert(PlayListItem *before, PlayListTrack *track)
{
     if(before)
         insert(m_container->indexOf(before), track);
     else
         add(track);
}

void PlayListModel::insert(int index, const QList<PlayListTrack *> &tracks)
{
    if(tracks.isEmpty())
        return;

    int flags = 0;

    for(PlayListTrack *track : qAsConst(tracks))
    {
        m_container->insertTrack(index, track);
        m_total_duration += track->duration();
        if(m_container->trackCount() == 1)
        {
            m_current_track = track;
            m_current = m_container->indexOf(track);
            flags |= CURRENT;
        }
        emit trackAdded(track);
    }
    //update current index
    m_current = m_container->indexOf(m_current_track);
    preparePlayState();
    flags |= STRUCTURE;
    emit listChanged(flags);
}

void PlayListModel::insert(int index, const QByteArray &json)
{
    insert(index, PlayListParser::deserialize(json));
}

void PlayListModel::insert(PlayListItem *before, const QList<PlayListTrack *> &tracks)
{
    if(before)
        insert(m_container->indexOf(before), tracks);
    else
        add(tracks);
}

void PlayListModel::insert(int index, const QString &path)
{
    insert(index, QStringList() << path);
}

void PlayListModel::insert(int index, const QStringList &paths)
{
    if(index < 0 || index >= m_container->count())
        add(paths);
    else
    {
        PlayListItem *before = m_container->item(index);
        m_loader->insert(before, paths);
    }
}

void PlayListModel::insert(int index, const QList<QUrl> &urls)
{
    QStringList paths;
    for(const QUrl &url : qAsConst(urls))
    {
        if(url.scheme() == "file")
            paths.append(QFileInfo(url.toLocalFile()).canonicalFilePath());
        else
            paths.append(url.toString());
    }
    insert(index, paths);
}

int PlayListModel::count() const
{
    return m_container->count();
}

int PlayListModel::trackCount() const
{
    return m_container->trackCount();
}

bool PlayListModel::isEmpty() const
{
    return m_container->isEmpty();
}

int PlayListModel::columnCount() const
{
    return MetaDataHelper::instance()->columnCount();
}

PlayListTrack* PlayListModel::currentTrack() const
{
    return m_container->isEmpty() ? nullptr : m_current_track;
}

PlayListTrack *PlayListModel::nextTrack() const
{
    if(m_container->isEmpty() || !m_play_state)
        return nullptr;
    if(m_stop_track && m_stop_track == currentTrack())
        return nullptr;
    if(!isEmptyQueue())
        return m_queued_songs.at(0);
    int index = m_play_state->nextIndex();
    if(index < 0 || (index + 1 > m_container->count()))
        return nullptr;
    return m_container->track(index);
}

int PlayListModel::indexOf(PlayListItem* item) const
{
    return m_container->indexOf(item);
}

PlayListItem* PlayListModel::item(int index) const
{
    return m_container->item(index);
}

PlayListTrack* PlayListModel::track(int index) const
{
    return m_container->track(index);
}

PlayListGroup* PlayListModel::group(int index) const
{
    return m_container->group(index);
}

int PlayListModel::currentIndex() const
{
    return m_current;
}

bool PlayListModel::setCurrent(int index)
{
    if(index > count()-1 || index < 0)
        return false;
    PlayListItem *item = m_container->item(index);
    if(item->isGroup())
    {
        index++;
        item = m_container->item(index);
    }
    m_current = index;
    m_current_track = dynamic_cast<PlayListTrack*> (item);
    emit listChanged(CURRENT);
    return true;
}

bool PlayListModel::setCurrent(PlayListTrack *track)
{
    if(!m_container->contains(track))
        return false;
    return setCurrent(m_container->indexOf(track));
}

bool PlayListModel::isTrack(int index) const
{
    if(index > count()-1 || index < 0)
        return false;
    return !m_container->item(index)->isGroup();
}

bool PlayListModel::isGroup(int index) const
{
    if(index > count()-1 || index < 0)
        return false;
    return m_container->item(index)->isGroup();
}

bool PlayListModel::next()
{
    if(m_stop_track == currentTrack())
    {
        m_stop_track = nullptr;
        emit listChanged(STOP_AFTER);
        return false;
    }
    if(!m_queued_songs.isEmpty())
    {
        m_current_track = m_queued_songs.dequeue();
        m_current = m_container->indexOf(m_current_track);
        emit listChanged(CURRENT | QUEUE);
        return true;
    }

    if(m_loader->isRunning())
        m_play_state->prepare();
    return m_play_state->next();
}

bool PlayListModel::previous()
{
    if(m_loader->isRunning())
        m_play_state->prepare();
    return m_play_state->previous();
}

void PlayListModel::clear()
{
    m_loader->finish();
    m_current = 0;
    m_stop_track = nullptr;
    m_container->clear();
    m_queued_songs.clear();
    m_total_duration = 0;
    m_play_state->resetState();
    emit listChanged(STRUCTURE | QUEUE | STOP_AFTER | CURRENT | SELECTION);
}

void PlayListModel::clearSelection()
{
    m_container->clearSelection();
    emit listChanged(SELECTION);
}

QList<PlayListItem *> PlayListModel::mid(int pos, int count) const
{
    return m_container->mid(pos, count);
}

bool PlayListModel::isSelected(int index) const
{
    return m_container->isSelected(index);
}

bool PlayListModel::contains(const QString &url)
{
    for(int i = 0; i < m_container->count(); ++i)
    {
        PlayListTrack *t = track(i);
        if(!t)
            continue;
        if(t->path() == url)
            return true;
    }
    return false;
}

int PlayListModel::indexOfTrack(int index) const
{
    return m_container->indexOfTrack(index);
}

PlayListTrack *PlayListModel::findTrack(int track_index) const
{
    return m_container->findTrack(track_index);
}

QList<PlayListItem *> PlayListModel::findTracks(const QString &str) const
{
    QList<PlayListItem *> items;
    PlayListItem *item = nullptr;
    if(str.isEmpty())
        return items;

    for(int i = 0; i < m_container->count(); ++i)
    {
        item = m_container->item(i);
        if(item->isGroup())
            continue;

        if(!item->formattedTitles().filter(str, Qt::CaseInsensitive).isEmpty())
            items.append(item);
    }
    return items;
}

void PlayListModel::setSelected(int index, bool selected)
{
    m_container->setSelected(index, selected);
    emit listChanged(SELECTION);
}

void PlayListModel::setSelected(const QList<PlayListTrack *> &tracks, bool selected)
{
    for(PlayListTrack *t : qAsConst(tracks))
        t->setSelected(selected);
    emit listChanged(SELECTION);
}

void PlayListModel::setSelected(const QList<PlayListItem *> &items, bool selected)
{
    for(PlayListItem *i : qAsConst(items))
        i->setSelected(selected);
    emit listChanged(SELECTION);
}

void PlayListModel::setSelected(int first, int last, bool selected)
{
    if(first > last)
    {
        setSelected(last, first, selected);
        return;
    }
    for(int index = first; index <= last; ++index)
    {
        PlayListItem *i = item(index);
        if(!i)
            continue;
        i->setSelected(selected);
    }
    emit listChanged(SELECTION);
}

void PlayListModel::setSelected(const QList<int> &indexes, bool selected)
{
    for(const int &idx : qAsConst(indexes))
        m_container->setSelected(idx, selected);
    emit listChanged(SELECTION);
}

void PlayListModel::removeSelected()
{
    removeSelection(false);
}

void PlayListModel::removeUnselected()
{
    removeSelection(true);
}

void PlayListModel::removeTrack (int i)
{
    int flags = removeTrackInternal(i);
    if(flags)
        emit listChanged(flags);
}

void PlayListModel::removeTrack (PlayListItem *track)
{
    if(m_container->contains(track))
        removeTrack (m_container->indexOf(track));
}

void PlayListModel::removeTracks(const QList<PlayListItem *> &items)
{
    int i = 0;
    int select_after_delete = -1;