/***************************************************************************
 *   Copyright (C) 2006-2019 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 <QPixmap>
#include <QResizeEvent>
#include <QPainter>
#include <QFont>
#include <QFontMetrics>
#include <QSettings>
#include <QMenu>
#include <QUrl>
#include <QApplication>
#include <QHelpEvent>
#include <QTimer>
#include <QMimeData>
#include <qmmpui/playlistitem.h>
#include <qmmpui/playlistmodel.h>
#include <qmmpui/qmmpuisettings.h>
#include <qmmpui/playlistmanager.h>
#include "listwidget.h"
#include "playlistheader.h"
#include "actionmanager.h"
#include "skin.h"
#include "popupwidget.h"
#include "horizontalslider.h"
#include "playlist.h"

#define INVALID_INDEX -1

ListWidget::ListWidget(QWidget *parent)
        : QWidget(parent)
{
    m_popupWidget = nullptr;

    m_skin = Skin::instance();
    m_ui_settings = QmmpUiSettings::instance();
    m_menu = new QMenu(this);
    m_timer = new QTimer(this);
    m_timer->setInterval(50);

    m_header = new PlayListHeader(this);
    m_hslider = new HorizontalSlider(this);
    m_update = false;
    m_drop_index = INVALID_INDEX;
    m_scroll_direction = NONE;
    m_prev_y = 0;
    m_anchor_index = INVALID_INDEX;
    m_pressed_index = INVALID_INDEX;
    m_first = 0;
    m_row_count = 0;
    m_count = 0;
    m_firstItem = nullptr;
    m_select_on_release = false;

    setAcceptDrops(true);
    setMouseTracking(true);

    readSettings();
    connect(m_skin, SIGNAL(skinChanged()), SLOT(updateSkin()));
    connect(m_ui_settings, SIGNAL(repeatableTrackChanged(bool)), SLOT(updateRepeatIndicator()));
    connect(m_timer, SIGNAL(timeout()), SLOT(autoscroll()));
    connect(m_hslider, SIGNAL(sliderMoved(int)), m_header, SLOT(scroll(int)));
    connect(m_hslider, SIGNAL(sliderMoved(int)), this, SLOT(update()));
    SET_ACTION(ActionManager::PL_SHOW_HEADER, this, SLOT(readSettings()));
}

ListWidget::~ListWidget()
{
    qDeleteAll(m_rows);
    m_rows.clear();
}

void ListWidget::readSettings()
{
    QSettings settings(Qmmp::configFile(), QSettings::IniFormat);
    settings.beginGroup("Skinned");
    m_show_protocol = settings.value ("pl_show_protocol", false).toBool();
    bool show_popup = settings.value("pl_show_popup", false).toBool();

    m_header->readSettings();
    m_header->setVisible(ACTION(ActionManager::PL_SHOW_HEADER)->isChecked());
    m_header->setGeometry(0,0,width(), m_header->requiredHeight());

    if (m_update)
    {
        m_drawer.readSettings();
        updateList(PlayListModel::STRUCTURE);
        if(m_popupWidget)
        {
            m_popupWidget->deleteLater();
            m_popupWidget = nullptr;
        }
    }
    else
    {
        m_update = true;
    }

    if(show_popup)
        m_popupWidget = new PlayListPopup::PopupWidget(this);
}

int ListWidget::visibleRows() const
{
    return m_row_count;
}

int ListWidget::firstVisibleIndex() const
{
    return m_first;
}

int ListWidget::anchorIndex() const
{
    return m_anchor_index;
}

void ListWidget::setAnchorIndex(int index)
{
    m_anchor_index = index;
    updateList(PlayListModel::SELECTION);
}

QMenu *ListWidget::menu()
{
    return m_menu;
}

PlayListModel *ListWidget::model()
{
    Q_ASSERT(m_model);
    return m_model;
}

void ListWidget::paintEvent(QPaintEvent *)
{
    QPainter painter(this);
    m_drawer.fillBackground(&painter, width(), height());
    painter.setLayoutDirection(Qt::LayoutDirectionAuto);
    bool rtl = (layoutDirection() == Qt::RightToLeft);

    painter.setClipRect(5,0,width() - 9, height());
    painter.translate(rtl ? m_header->offset() : -m_header->offset(), 0);

    for (int i = 0; i < m_rows.size(); ++i )
    {
        m_drawer.drawBackground(&painter, m_rows[i]);

        if(m_rows[i]->flags & ListWidgetRow::GROUP)
        {
            m_drawer.drawSeparator(&painter, m_rows[i], rtl);
            continue;
        }

        m_drawer.drawTrack(&painter, m_rows[i], rtl);
    }
    //draw drop line
    if(m_drop_index != INVALID_INDEX)
    {
        m_drawer.drawDropLine(&painter, m_drop_index - m_first, width(),
                              m_header->isVisible() ? m_header->height() : 0);
    }
}

void ListWidget::mouseDoubleClickEvent (QMouseEvent *e)
{
    int y = e->y();
    int index = indexAt(y);
    if (INVALID_INDEX != index)
    {
        m_model->setCurrent(index);
        emit doubleClicked();
        update();
    }
}

void ListWidget::mousePressEvent(QMouseEvent *e)
{
    if(m_popupWidget)
        m_popupWidget->hide();

    int index = indexAt(e->y());

    if (INVALID_INDEX != index && m_model->count() > index)
    {
        m_pressed_index = index;
        if(e->button() == Qt::RightButton)
        {
            if(!m_model->isSelected(index))
            {
                m_anchor_index = m_pressed_index;
                m_model->clearSelection();
                m_model->setSelected(index, true);
            }
            if(m_model->isGroup(index) && m_model->selectedTracks().isEmpty())
            {
                m_anchor_index = m_pressed_index;
                PlayListGroup *group = m_model->group(index);
                m_model->setSelected(group->tracks());
            }
            QWidget::mousePressEvent(e);
            return;
        }

        if (m_model->isSelected(index) && (e->modifiers() == Qt::NoModifier))
        {
            m_select_on_release = true;
            QWidget::mousePressEvent(e);
            return;
        }

        if ((Qt::ShiftModifier & e->modifiers()))
        {
            int prev_anchor_index = m_anchor_index;
            m_anchor_index = m_pressed_index;
            m_model->setSelected(m_pressed_index, prev_anchor_index, true);
        }
        else //ShiftModifier released
        {
            m_anchor_index = m_pressed_index;
            if ((Qt::ControlModifier & e->modifiers()))
            {
                m_model->setSelected(index, !m_model->isSelected(index));
            }
            else //ControlModifier released
            {
                m_model->clearSelection();
                m_model->setSelected(index, true);
            }

        }
        update();
    }
    QWidget::mousePressEvent(e);
}

void ListWidget::resizeEvent(QResizeEvent *e)
{
    m_header->setGeometry(0,0,width(), m_header->requiredHeight());
    m_hslider->setGeometry(5,height() - 7, width() - 10, 7);
    updateList(PlayListModel::STRUCTURE);
    QWidget::resizeEvent(e);
}

void ListWidget::wheelEvent (QWheelEvent *e)
{
    if (m_model->count() <= m_row_count)
        return;
    if ((m_first == 0 && e->delta() > 0) ||
            ((m_first == m_model->count() - m_row_count) && e->delta() < 0))
        return;
    m_first -= e->delta()/40;  //40*3 TODO: add step to config
    if (m_first < 0)
        m_first = 0;

    if (m_first > m_model->count() - m_row_count)
        m_first = m_model->count() - m_row_count;

    updateList(PlayListModel::STRUCTURE);
}

bool ListWidget::event (QEvent *e)
{
    if(m_popupWidget)
    {
        if(e->type() == QEvent::ToolTip)
        {
            QHelpEvent *helpEvent = (QHelpEvent *) e;
            int index = indexAt(helpEvent->y());
            if(index < 0 || !m_model->isTrack(index))
            {
                m_popupWidget->deactivate();
                return QWidget::event(e);
            }
            e->accept();