picture viewer fixes

src/main/java/cz/kamma/kfmanager/ui/FileEditor.java

@@ -18,6 +18,8 @@ public class FileEditor extends JDialog {
     private JTextArea textArea;
     private JScrollPane scrollPane;
     private File file;
+    private java.util.List<File> imageFiles = new java.util.ArrayList<>();
+    private int currentImageIndex = -1;
     private AppConfig config;
     private boolean modified = false;
     private boolean readOnly;
@@ -54,6 +56,10 @@ public class FileEditor extends JDialog {
         this.config = config;
         this.readOnly = readOnly;
         
+        if (isImageFile(file)) {
+            initImageList();
+        }
+        
         initComponents();
         loadFile();
         
@@ -580,6 +586,19 @@ public class FileEditor extends JDialog {
             if (undoManager.canRedo()) undoManager.redo();
         }, KeyStroke.getKeyStroke(KeyEvent.VK_Y, InputEvent.CTRL_DOWN_MASK), JComponent.WHEN_IN_FOCUSED_WINDOW);
 
+        // Doprava/Doleva a Mezerník pro listování obrázků
+        rootPane.registerKeyboardAction(e -> {
+            if (isImageFile(file)) nextImage();
+        }, KeyStroke.getKeyStroke(KeyEvent.VK_RIGHT, 0), JComponent.WHEN_IN_FOCUSED_WINDOW);
+
+        rootPane.registerKeyboardAction(e -> {
+            if (isImageFile(file)) prevImage();
+        }, KeyStroke.getKeyStroke(KeyEvent.VK_LEFT, 0), JComponent.WHEN_IN_FOCUSED_WINDOW);
+
+        rootPane.registerKeyboardAction(e -> {
+            if (isImageFile(file)) nextImage();
+        }, KeyStroke.getKeyStroke(KeyEvent.VK_SPACE, 0), JComponent.WHEN_IN_FOCUSED_WINDOW);
+
         // Ctrl+Shift+Z - Redo (alternative shortcut)
         rootPane.registerKeyboardAction(e -> {
             if (undoManager.canRedo()) undoManager.redo();
@@ -867,16 +886,45 @@ public class FileEditor extends JDialog {
         try {
             ImageIcon icon = new ImageIcon(file.getAbsolutePath());
             if (icon.getImageLoadStatus() == MediaTracker.COMPLETE) {
+                // Get image dimensions
+                int imgW = icon.getIconWidth();
+                int imgH = icon.getIconHeight();
+
+                // Get screen size constraints
+                GraphicsConfiguration gc = getGraphicsConfiguration();
+                Rectangle screenBounds = gc.getBounds();
+                Insets screenInsets = Toolkit.getDefaultToolkit().getScreenInsets(gc);
+                int maxW = screenBounds.width - screenInsets.left - screenInsets.right - 40;
+                int maxH = screenBounds.height - screenInsets.top - screenInsets.bottom - 100;
+
+                // Scale image if it's too large
+                Image scaledImage = icon.getImage();
+                boolean scaled = false;
+                if (imgW > maxW || imgH > maxH) {
+                    double ratio = Math.min((double) maxW / imgW, (double) maxH / imgH);
+                    imgW = (int) (imgW * ratio);
+                    imgH = (int) (imgH * ratio);
+                    scaledImage = scaledImage.getScaledInstance(imgW, imgH, Image.SCALE_SMOOTH);
+                    icon = new ImageIcon(scaledImage);
+                    scaled = true;
+                }
+
                 JLabel label = new JLabel(icon);
                 label.setHorizontalAlignment(JLabel.CENTER);
                 scrollPane.setViewportView(label);
                 
-                statusPosLabel.setText(String.format("Obraz: %d x %d px", 
+                String statusText = String.format("Obraz: %d x %d px", imgW, imgH);
-                    icon.getIconWidth(), icon.getIconHeight()));
+                if (scaled) statusText += " (zmenšeno)";
-                statusSelLabel.setText(String.format("Velikost: %s", formatSize(file.length())));
+                statusPosLabel.setText(statusText);
                 
-                // Adjust window size based on image size
+                String labelText = String.format("Velikost: %s", formatSize(file.length()));
-                adjustWindowSizeForImage(icon.getIconWidth(), icon.getIconHeight());
+                if (imageFiles.size() > 1) {
+                    labelText += String.format("  [%d / %d]", currentImageIndex + 1, imageFiles.size());
+                }
+                statusSelLabel.setText(labelText);
+                
+                // Adjust window size based on (possibly scaled) image size
+                adjustWindowSizeForImage(imgW, imgH);
                 
                 // Disable search and hex for images
                 if (northPanel != null) {
@@ -928,6 +976,46 @@ public class FileEditor extends JDialog {
         String pre = "KMGTPE".charAt(exp-1) + "";
         return String.format("%.1f %sB", size / Math.pow(1024, exp), pre);
     }
+
+    private void initImageList() {
+        File parent = file.getParentFile();
+        if (parent != null && parent.isDirectory()) {
+            File[] files = parent.listFiles();
+            if (files != null) {
+                java.util.Arrays.sort(files);
+                for (File f : files) {
+                    if (f.isFile() && isImageFile(f)) {
+                        imageFiles.add(f);
+                        if (f.equals(file)) {
+                            currentImageIndex = imageFiles.size() - 1;
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    private void nextImage() {
+        if (imageFiles.size() > 1) {
+            currentImageIndex = (currentImageIndex + 1) % imageFiles.size();
+            file = imageFiles.get(currentImageIndex);
+            updateTitle();
+            loadImage();
+        }
+    }
+
+    private void prevImage() {
+        if (imageFiles.size() > 1) {
+            currentImageIndex = (currentImageIndex - 1 + imageFiles.size()) % imageFiles.size();
+            file = imageFiles.get(currentImageIndex);
+            updateTitle();
+            loadImage();
+        }
+    }
+
+    private void updateTitle() {
+        setTitle((readOnly ? "Prohlížeč - " : "Editor - ") + file.getName() + (modified ? " *" : ""));
+    }
     
     private void saveFile() {
         try {
@@ -969,14 +1057,6 @@ public class FileEditor extends JDialog {
         updateTitle();
     }
     
-    private void updateTitle() {
-        String title = (readOnly ? "Prohlížeč - " : "Editor - ") + file.getName();
-        if (!readOnly && modified) {
-            title += " *";
-        }
-        setTitle(title);
-    }
-    
     private void changeFont() {
         Font newFont = FontChooserDialog.showDialog(this, textArea.getFont());
         if (newFont != null) {