File indexing completed on 2024-04-28 04:20:03

 /*
     SPDX-FileCopyrightText: 2022 Friedrich W. H. Kossebau <kossebau@kde.org>
 
     SPDX-License-Identifier: LGPL-2.1-or-later
 */
 
 #include "imageview.hpp"
 
 // Qt
 #include <QLabel>
 #include <QPalette>
 #include <QPixmap>
 #include <QScrollArea>
 #include <QVBoxLayout>
 
 namespace Kodaskanna
 {
 namespace ImageSource
 {
 
 // work-around for QLabel not having native proportional scaling of pixmaps
 class ProportionalImageLabel : public QLabel
 {
 public:
     ProportionalImageLabel() = default;
 
     /// Reinvent setter original method
     void setPixmap(const QPixmap &pixmap)
     {
         m_originalPixmapWidth = pixmap.width();
         m_originalPixmapHeight = pixmap.height();
 
         adjustContentsMargins();
         QLabel::setPixmap(pixmap);
     }
 
 public: // QWidget API
     void resizeEvent(QResizeEvent *event) override
     {
         adjustContentsMargins();
         QLabel::resizeEvent(event);
     }
 
 private:
     void adjustContentsMargins()
     {
         if ((m_originalPixmapWidth <= 0) || (m_originalPixmapHeight <= 0)) {
             return;
         }
 
         const int width = this->width();
         const int height = this->height();
 
         if ((width <= 0) || (height <= 0)) {
             return;
         }
 
         if (width * m_originalPixmapHeight > height * m_originalPixmapWidth) {
             const int horizontalMargin = (width - (m_originalPixmapWidth * height / m_originalPixmapHeight)) / 2;
             setContentsMargins({horizontalMargin, 0, horizontalMargin, 0});
         } else {
             const int verticalMargin = (height - (m_originalPixmapHeight * width / m_originalPixmapWidth)) / 2;
             setContentsMargins({0, verticalMargin, 0, verticalMargin});
         }
     }
 
 private:
     int m_originalPixmapWidth = 0;
     int m_originalPixmapHeight = 0;
 };
 
 ImageView::ImageView(QWidget *parent)
     : QWidget(parent)
     , m_scrollArea(new QScrollArea)
     , m_imageLabel(new ProportionalImageLabel)
 {
     m_imageLabel->setSizePolicy(QSizePolicy::Ignored, QSizePolicy::Ignored);
     m_imageLabel->setScaledContents(true);
 
     m_scrollArea->setBackgroundRole(QPalette::Dark);
     m_scrollArea->setAlignment(Qt::AlignCenter);
     m_scrollArea->setWidget(m_imageLabel);
     m_scrollArea->setWidgetResizable(true);
 
     auto *layout = new QVBoxLayout;
     layout->setContentsMargins({});
     layout->addWidget(m_scrollArea);
     setLayout(layout);
 }
 
 ImageView::~ImageView() = default;
 
 void ImageView::setImage(const QImage &image)
 {
     m_image = image;
     m_imageLabel->setPixmap(QPixmap::fromImage(image));
 }
 
 }
 }