cantata/widgets/coverwidget.cpp

/*
 * Cantata
 *
 * Copyright (c) 2011-2017 Craig Drummond <craig.p.drummond@gmail.com>
 *
 * ----
 *
 * 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; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#include "coverwidget.h"
#include "gui/currentcover.h"
#include "gui/covers.h"
#include "gui/settings.h"
#include "mpd-interface/song.h"
#include "context/view.h"
#include "support/gtkstyle.h"
#include "support/utils.h"
#include "online/onlineservice.h"
#ifdef Q_OS_MAC
#include "support/osxstyle.h"
#endif
#include <QLinearGradient>
#include <QPen>
#include <QMouseEvent>
#include <QApplication>
#include <QPainter>
#include <QBoxLayout>
#include <QSpacerItem>

static const int constBorder=1;

CoverLabel::CoverLabel(QWidget *p)
    : QLabel(p)
    , pressed(false)
{
}

bool CoverLabel::event(QEvent *event)
{
    switch(event->type()) {
    case QEvent::ToolTip: {
        const Song &current=CurrentCover::self()->song();
        if (current.isEmpty() || (current.isStream() && !current.isCantataStream() && !current.isCdda()) || OnlineService::showLogoAsCover(current)) {
            setToolTip(QString());
            break;
        }
        QString toolTip=QLatin1String("<table>");
        const QImage &img=CurrentCover::self()->image();

        if (!current.composer().isEmpty()) {
            toolTip+=tr("<tr><td align=\"right\"><b>Composer:</b></td><td>%1</td></tr>").arg(current.composer());
        }
        if (!current.performer().isEmpty() && current.performer()!=current.albumArtist()) {
            toolTip+=tr("<tr><td align=\"right\"><b>Performer:</b></td><td>%1</td></tr>").arg(current.performer());
        }
        toolTip+=tr("<tr><td align=\"right\"><b>Artist:</b></td><td>%1</td></tr>"
                    "<tr><td align=\"right\"><b>Album:</b></td><td>%2</td></tr>"
                    "<tr><td align=\"right\"><b>Year:</b></td><td>%3</td></tr>").arg(current.albumArtist()).arg(current.album).arg(QString::number(current.year));
        toolTip+="</table>";
        if (!img.isNull()) {
            if (img.size().width()>Covers::constMaxSize.width() || img.size().height()>Covers::constMaxSize.height()) {
                toolTip+=QString("<br/>%1").arg(View::encode(img.scaled(Covers::constMaxSize, Qt::KeepAspectRatio, Qt::SmoothTransformation)));
            } else if (CurrentCover::self()->fileName().isEmpty() || !QFile::exists(CurrentCover::self()->fileName())) {
                toolTip+=QString("<br/>%1").arg(View::encode(img));
            } else {
                toolTip+=QString("<br/><img src=\"%1\"/>").arg(CurrentCover::self()->fileName());
            }
        }
        setToolTip(toolTip);
        break;
    }
    case QEvent::MouseButtonPress:
        if (Qt::LeftButton==static_cast<QMouseEvent *>(event)->button() && Qt::NoModifier==static_cast<QMouseEvent *>(event)->modifiers()) {
            pressed=true;
        }
        break;
    case QEvent::MouseButtonRelease:
        if (pressed && Qt::LeftButton==static_cast<QMouseEvent *>(event)->button() && !QApplication::overrideCursor()) {
            static_cast<CoverWidget*>(parentWidget())->emitClicked();
        }
        pressed=false;
        break;
    default:
        break;
    }
    return QLabel::event(event);
}

void CoverLabel::paintEvent(QPaintEvent *)
{
    if (pix.isNull()) {
        return;
    }
    QPainter p(this);
    QSize layoutSize = pix.size() / pix.DEVICE_PIXEL_RATIO();
    QRect r((width()-layoutSize.width())/2, (height()-layoutSize.height())/2, layoutSize.width(), layoutSize.height());

    p.drawPixmap(r, pix);
    if (underMouse()) {
        #ifdef Q_OS_MAC
        QPen pen(OSXStyle::self()->viewPalette().color(QPalette::Highlight), 2);
        #else
        QPen pen(palette().color(QPalette::Highlight), 2);
        #endif
        pen.setJoinStyle(Qt::MiterJoin);
        p.setPen(pen);
        p.drawRect(r.adjusted(1, 1, -1, -1));
    }
}

void CoverLabel::updatePix()
{
    QImage img=CurrentCover::self()->image();
    if (img.isNull()) {
        return;
    }
    int size=height();
    double pixRatio=qApp->devicePixelRatio();
    size*=pixRatio;
    img=img.scaled(size, size, Qt::KeepAspectRatio, Qt::SmoothTransformation);
    img.setDevicePixelRatio(pixRatio);
    if (pix.isNull() || pix.size()!=img.size()) {
        pix=QPixmap(img.size());
        pix.setDevicePixelRatio(pixRatio);
    }
    pix.fill(Qt::transparent);
    QPainter painter(&pix);
    painter.drawImage(0, 0, img);
    repaint();
}

void CoverLabel::deletePix()
{
    if (!pix.isNull()) {
        pix=QPixmap();
    }
}

CoverWidget::CoverWidget(QWidget *parent)
    : QWidget(parent)
{
    QBoxLayout *l=new QBoxLayout(QBoxLayout::LeftToRight, this);
    l->setMargin(0);
    l->setSpacing(0);
    l->addItem(new QSpacerItem(qMax(8, Utils::layoutSpacing(this)), 4, QSizePolicy::Fixed, QSizePolicy::Fixed));
    label=new CoverLabel(this);
    l->addWidget(label);
    label->setStyleSheet(QString("QLabel {border: %1px solid transparent} QToolTip {background-color:#111111; color: #DDDDDD}").arg(constBorder));
    label->setAttribute(Qt::WA_Hover, true);
}

CoverWidget::~CoverWidget()
{
}

void CoverWidget::setSize(int min)
{
    label->setFixedSize(min, min);
}

void CoverWidget::setEnabled(bool e)
{
    if (e) {
        connect(CurrentCover::self(), SIGNAL(coverImage(QImage)), this, SLOT(coverImage(QImage)));
        coverImage(QImage());
    } else {
        label->deletePix();
        disconnect(CurrentCover::self(), SIGNAL(coverImage(QImage)), this, SLOT(coverImage(QImage)));
    }
    setVisible(e);
    label->setEnabled(e);
}

void CoverWidget::coverImage(const QImage &)
{
    label->updatePix();
}