feat: auto long image mode

app/graphicsview.cpp

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: 2022 Gary Wang <wzc782970009@gmail.com>
+// SPDX-FileCopyrightText: 2025 Gary Wang <git@blumia.net>
 //
 // SPDX-License-Identifier: MIT
 
@@ -124,6 +124,7 @@ void GraphicsView::resetTransform()
 void GraphicsView::zoomView(qreal scaleFactor)
 {
     m_enableFitInView = false;
+    m_longImageMode = false;
     scale(scaleFactor, scaleFactor);
     applyTransformationModeByScaleFactor();
     emit navigatorViewRequired(!isThingSmallerThanWindowWith(transform()), transform());
@@ -140,6 +141,10 @@ void GraphicsView::rotateView(bool clockwise)
                   0,                  0,                  1);
     tf = transform() * tf;
     setTransform(tf);
+    
+    // Apply transformation mode but don't emit navigator signal here
+    // Let displayScene() handle the navigator visibility correctly
+    applyTransformationModeByScaleFactor();
 }
 
 void GraphicsView::flipView(bool horizontal)
@@ -261,6 +266,69 @@ void GraphicsView::fitByOrientation(Qt::Orientation ori, bool scaleDownOnly)
     emit navigatorViewRequired(!isThingSmallerThanWindowWith(transform()), transform());
 }
 
+bool GraphicsView::isLongImage() const
+{
+    // Get the transformed image size (considering rotation and other transforms)
+    QRectF transformedRect = transform().mapRect(sceneRect());
+    QSizeF imageSize = transformedRect.size();
+    
+    if (imageSize.isEmpty()) return false;
+    
+    qreal aspectRatio = imageSize.width() / imageSize.height();
+    
+    // Check if aspect ratio exceeds 5:2 (wide) or 2:5 (tall)
+    return aspectRatio > 2.5 || aspectRatio < 0.4;
+}
+
+bool GraphicsView::shouldEnterLongImageMode() const
+{
+    // Check if long image mode is enabled in settings
+    if (!Settings::instance()->autoLongImageMode()) return false;
+    
+    // Check if image is a long image
+    if (!isLongImage()) return false;
+    
+    // Check if transformed image size is larger than the size of the view
+    QSizeF imageSize = transform().mapRect(sceneRect()).size();
+    QSizeF viewSize = viewport()->size();
+    
+    return imageSize.width() > viewSize.width() || imageSize.height() > viewSize.height();
+}
+
+void GraphicsView::applyLongImageMode()
+{
+    if (!shouldEnterLongImageMode()) {
+        m_longImageMode = false;
+        return;
+    }
+    
+    m_longImageMode = true;
+    applyLongImageModeDirect();
+}
+
+void GraphicsView::applyLongImageModeDirect()
+{
+    // Determine image orientation based on current transform
+    QRectF transformedRect = transform().mapRect(sceneRect());
+    qreal aspectRatio = transformedRect.width() / transformedRect.height();
+    bool isTallImage = aspectRatio < 0.4;
+    bool isWideImage = aspectRatio > 2.5;
+    
+    // Use fitByOrientation with the migrated logic
+    if (isTallImage) {
+        // Tall image (height >> width): fit by width
+        fitByOrientation(Qt::Horizontal, true);  // scaleDownOnly = true
+    } else if (isWideImage) {
+        // Wide image (width >> height): fit by height
+        fitByOrientation(Qt::Vertical, true);    // scaleDownOnly = true
+    }
+}
+
+bool GraphicsView::isInLongImageMode() const
+{
+    return m_longImageMode;
+}
+
 void GraphicsView::displayScene()
 {
     if (shouldAvoidTransform()) {
@@ -268,8 +336,23 @@ void GraphicsView::displayScene()
         return;
     }
 
+    // Check if should apply long image mode
+    if (shouldEnterLongImageMode()) {
+        applyLongImageMode();
+        m_firstUserMediaLoaded = true;
+        return;
+    }
+
+    // Not in long image mode
+    m_longImageMode = false;
+
     if (isSceneBiggerThanView()) {
         fitInView(sceneRect(), Qt::KeepAspectRatio);
+        // After fitInView, the image should fit the window, so hide navigator
+        emit navigatorViewRequired(false, transform());
+    } else {
+        // Image is already smaller than window, no navigator needed
+        emit navigatorViewRequired(false, transform());
     }
 
     m_enableFitInView = true;
@@ -291,6 +374,11 @@ void GraphicsView::setEnableAutoFitInView(bool enable)
     m_enableFitInView = enable;
 }
 
+void GraphicsView::setLongImageMode(bool enable)
+{
+    m_longImageMode = enable;
+}
+
 bool GraphicsView::avoidResetTransform() const
 {
     return m_avoidResetTransform;
@@ -363,7 +451,12 @@ void GraphicsView::wheelEvent(QWheelEvent *event)
 
 void GraphicsView::resizeEvent(QResizeEvent *event)
 {
-    if (m_enableFitInView) {
+    if (m_longImageMode) {
+        // In long image mode, reapply long image logic on resize
+        // We directly apply the long image mode logic without rechecking
+        // if we should enter long image mode, as the mode is already active
+        applyLongImageModeDirect();
+    } else if (m_enableFitInView) {
         bool originalSizeSmallerThanWindow = isThingSmallerThanWindowWith(resetScale(transform()));
         if (originalSizeSmallerThanWindow && scaleFactor() >= 1) {
             // no longer need to do fitInView()