dark theme support

diylc/diylc-swing/src/main/java/org/diylc/DIYLCStarter.java

@@ -33,6 +33,7 @@ import org.diylc.appframework.miscutils.PropertyInjector;
 import org.diylc.appframework.miscutils.Utils;
 import org.diylc.swingframework.export.DrawingExporter;
 import org.diylc.swingframework.fonts.FontOptimizer;
+import org.diylc.utils.ThemeUtils;
 import com.thoughtworks.xstream.XStream;
 import org.diylc.common.IPlugInPort;
 import org.diylc.core.IView;
@@ -71,6 +72,9 @@ public class DIYLCStarter {
 	}
 
 	public static void runDIYLC(String[] args) {
+		// Apply OS dark theme settings before creating any UI components
+		ThemeUtils.applyOSDarkTheme();
+		
 		// Initialize splash screen
 		DIYLCSplash splash = null;
 		Exception splashException = null;
@@ -137,6 +141,8 @@ public class DIYLCStarter {
 
 		try {
 			UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
+			// Apply dark theme colors if dark mode is detected
+			ThemeUtils.applyDarkThemeColors();
 		} catch (Exception e) {
 			LOG.error("Could not set Look&Feel", e);
 		}

diylc/diylc-swing/src/main/java/org/diylc/utils/ThemeUtils.java

@@ -0,0 +1,381 @@
+/*
+ * 
+ * DIY Layout Creator (DIYLC). Copyright (c) 2009-2025 held jointly by the individual authors.
+ * 
+ * This file is part of DIYLC.
+ * 
+ * DIYLC 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 3 of the
+ * License, or (at your option) any later version.
+ * 
+ * DIYLC 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 DIYLC. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+package org.diylc.utils;
+
+import java.awt.Color;
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import javax.swing.UIManager;
+import org.apache.log4j.Logger;
+import org.diylc.appframework.miscutils.Utils;
+
+/**
+ * Utility class for detecting and applying OS dark theme settings.
+ * 
+ * Note: Modern Java (11+) with system Look and Feel should automatically
+ * respect OS dark theme settings, but this utility provides explicit detection
+ * and ensures compatibility with older Java versions.
+ * 
+ * @author Branislav Stojkovic
+ */
+public class ThemeUtils {
+
+  private static final Logger LOG = Logger.getLogger(ThemeUtils.class);
+
+  /**
+   * Detects and applies OS dark theme settings.
+   * This must be called before creating any AWT/Swing components.
+   */
+  public static void applyOSDarkTheme() {
+    try {
+      if (Utils.isMac()) {
+        applyMacOSDarkTheme();
+      } else if (Utils.isWindows()) {
+        detectWindowsDarkTheme();
+      } else {
+        detectLinuxDarkTheme();
+      }
+    } catch (Exception e) {
+      LOG.warn("Error detecting OS dark theme: " + e.getMessage(), e);
+    }
+  }
+
+  /**
+   * Applies dark theme colors to UIManager after the Look and Feel is set.
+   * This should be called after UIManager.setLookAndFeel().
+   * 
+   * @return true if dark mode was detected and colors were applied, false otherwise
+   */
+  public static boolean applyDarkThemeColors() {
+    try {
+      if (Utils.isMac()) {
+        return applyMacOSDarkThemeColors();
+      } else if (Utils.isWindows()) {
+        return applyWindowsDarkThemeColors();
+      } else {
+        return applyLinuxDarkThemeColors();
+      }
+    } catch (Exception e) {
+      LOG.warn("Error applying dark theme colors: " + e.getMessage(), e);
+      return false;
+    }
+  }
+
+  /**
+   * Detects and applies macOS dark theme settings.
+   */
+  private static void applyMacOSDarkTheme() {
+    // macOS: Check if dark mode is enabled
+    // Modern Java (11+) should automatically detect this, but we'll check explicitly
+    String appearance = System.getProperty("apple.awt.application.appearance");
+    if (appearance == null) {
+      // Try to detect dark mode via system command (for older Java versions)
+      try {
+        Process process = Runtime.getRuntime().exec(
+            new String[]{"defaults", "read", "-g", "AppleInterfaceStyle"});
+        BufferedReader reader = new BufferedReader(
+            new InputStreamReader(process.getInputStream()));
+        String result = reader.readLine();
+        if ("Dark".equals(result)) {
+          // Note: Setting this property after JVM start may not always work,
+          // but it's worth trying for older Java versions
+          System.setProperty("apple.awt.application.appearance", "NSAppearanceNameDarkAqua");
+          LOG.info("Detected macOS dark mode - attempting to apply dark theme");
+        } else {
+          LOG.debug("macOS light mode detected");
+        }
+      } catch (Exception e) {
+        // If detection fails, that's okay - modern Java will handle it automatically
+        LOG.debug("Could not detect macOS theme via defaults command: " + e.getMessage());
+      }
+    } else if ("NSAppearanceNameDarkAqua".equals(appearance)) {
+      LOG.info("macOS dark mode already detected by JVM");
+    } else {
+      LOG.debug("macOS appearance: " + appearance);
+    }
+  }
+
+  /**
+   * Detects Windows dark theme settings.
+   */
+  private static void detectWindowsDarkTheme() {
+    // Windows: Try to detect dark theme via registry
+    try {
+      Process process = Runtime.getRuntime().exec(
+          new String[]{"reg", "query", 
+              "HKCU\\Software\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize", 
+              "/v", "AppsUseLightTheme"});
+      BufferedReader reader = new BufferedReader(
+          new InputStreamReader(process.getInputStream()));
+      String line;
+      while ((line = reader.readLine()) != null) {
+        if (line.contains("AppsUseLightTheme")) {
+          // If value is 0, dark theme is enabled
+          if (line.contains("0x0") || line.endsWith("0")) {
+            // For Windows, the system Look and Feel should automatically respect dark mode
+            // in Java 11+, but we can log it for debugging
+            LOG.info("Detected Windows dark mode");
+          }
+          break;
+        }
+      }
+    } catch (Exception e) {
+      LOG.debug("Could not detect Windows theme via registry: " + e.getMessage());
+    }
+  }
+
+  /**
+   * Detects Linux dark theme settings.
+   */
+  private static void detectLinuxDarkTheme() {
+    // Linux: Check GTK theme or environment variables
+    try {
+      String gtkTheme = System.getenv("GTK_THEME");
+      if (gtkTheme != null && (gtkTheme.toLowerCase().contains("dark") || 
+          gtkTheme.toLowerCase().contains("Dark"))) {
+        LOG.info("Detected Linux dark theme: " + gtkTheme);
+      }
+      // Also check COLORFGBG environment variable (used by some terminals/desktops)
+      String colorFgBg = System.getenv("COLORFGBG");
+      if (colorFgBg != null) {
+        // Format is typically "15;0" where second number < 8 indicates dark background
+        String[] parts = colorFgBg.split(";");
+        if (parts.length > 1) {
+          try {
+            int bgColor = Integer.parseInt(parts[parts.length - 1]);
+            if (bgColor < 8) {
+              LOG.info("Detected Linux dark background via COLORFGBG");
+            }
+          } catch (NumberFormatException e) {
+            // Ignore
+          }
+        }
+      }
+    } catch (Exception e) {
+      LOG.debug("Could not detect Linux theme: " + e.getMessage());
+    }
+  }
+
+  /**
+   * Applies macOS dark theme colors to UIManager.
+   * @return true if dark mode is active
+   */
+  private static boolean applyMacOSDarkThemeColors() {
+    boolean isDarkMode = false;
+    
+    // Check if dark mode is active
+    String appearance = System.getProperty("apple.awt.application.appearance");
+    if (appearance == null) {
+      try {
+        Process process = Runtime.getRuntime().exec(
+            new String[]{"defaults", "read", "-g", "AppleInterfaceStyle"});
+        BufferedReader reader = new BufferedReader(
+            new InputStreamReader(process.getInputStream()));
+        String result = reader.readLine();
+        isDarkMode = "Dark".equals(result);
+      } catch (Exception e) {
+        LOG.debug("Could not detect macOS theme: " + e.getMessage());
+        // Try to infer from current UI colors
+        Color menuBarBg = UIManager.getColor("MenuBar.background");
+        if (menuBarBg != null && isDarkColor(menuBarBg)) {
+          isDarkMode = true;
+        }
+      }
+    } else {
+      isDarkMode = "NSAppearanceNameDarkAqua".equals(appearance);
+    }
+
+    if (isDarkMode) {
+      LOG.info("Applying macOS dark theme colors");
+      applyDarkColors();
+      return true;
+    }
+    return false;
+  }
+
+  /**
+   * Applies Windows dark theme colors to UIManager.
+   * @return true if dark mode is active
+   */
+  private static boolean applyWindowsDarkThemeColors() {
+    boolean isDarkMode = false;
+    
+    try {
+      Process process = Runtime.getRuntime().exec(
+          new String[]{"reg", "query", 
+              "HKCU\\Software\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize", 
+              "/v", "AppsUseLightTheme"});
+      BufferedReader reader = new BufferedReader(
+          new InputStreamReader(process.getInputStream()));
+      String line;
+      while ((line = reader.readLine()) != null) {
+        if (line.contains("AppsUseLightTheme")) {
+          // If value is 0, dark theme is enabled
+          if (line.contains("0x0") || line.endsWith("0")) {
+            isDarkMode = true;
+          }
+          break;
+        }
+      }
+    } catch (Exception e) {
+      LOG.debug("Could not detect Windows theme: " + e.getMessage());
+      // Try to infer from current UI colors
+      Color menuBarBg = UIManager.getColor("MenuBar.background");
+      if (menuBarBg != null && isDarkColor(menuBarBg)) {
+        isDarkMode = true;
+      }
+    }
+
+    if (isDarkMode) {
+      LOG.info("Applying Windows dark theme colors");
+      applyDarkColors();
+      return true;
+    }
+    return false;
+  }
+
+  /**
+   * Applies Linux dark theme colors to UIManager.
+   * @return true if dark mode is active
+   */
+  private static boolean applyLinuxDarkThemeColors() {
+    boolean isDarkMode = false;
+    
+    try {
+      String gtkTheme = System.getenv("GTK_THEME");
+      if (gtkTheme != null && (gtkTheme.toLowerCase().contains("dark") || 
+          gtkTheme.toLowerCase().contains("Dark"))) {
+        isDarkMode = true;
+      }
+      
+      // Also check COLORFGBG
+      if (!isDarkMode) {
+        String colorFgBg = System.getenv("COLORFGBG");
+        if (colorFgBg != null) {
+          String[] parts = colorFgBg.split(";");
+          if (parts.length > 1) {
+            try {
+              int bgColor = Integer.parseInt(parts[parts.length - 1]);
+              if (bgColor < 8) {
+                isDarkMode = true;
+              }
+            } catch (NumberFormatException e) {
+              // Ignore
+            }
+          }
+        }
+      }
+      
+      // Try to infer from current UI colors
+      if (!isDarkMode) {
+        Color menuBarBg = UIManager.getColor("MenuBar.background");
+        if (menuBarBg != null && isDarkColor(menuBarBg)) {
+          isDarkMode = true;
+        }
+      }
+    } catch (Exception e) {
+      LOG.debug("Could not detect Linux theme: " + e.getMessage());
+    }
+
+    if (isDarkMode) {
+      LOG.info("Applying Linux dark theme colors");
+      applyDarkColors();
+      return true;
+    }
+    return false;
+  }
+
+  /**
+   * Applies dark theme colors to common UI components.
+   * Only overrides colors that would cause visibility issues (e.g., dark text on dark background).
+   */
+  private static void applyDarkColors() {
+    // Menu bar and menu colors - fix text colors if background is dark
+    Color menuBarBg = UIManager.getColor("MenuBar.background");
+    Color menuBarFg = UIManager.getColor("MenuBar.foreground");
+    
+    if (menuBarBg != null && isDarkColor(menuBarBg)) {
+      // Background is dark, ensure text is light
+      if (menuBarFg == null || isDarkColor(menuBarFg)) {
+        UIManager.put("MenuBar.foreground", Color.WHITE);
+      }
+      
+      // Fix menu colors
+      Color menuBg = UIManager.getColor("Menu.background");
+      Color menuFg = UIManager.getColor("Menu.foreground");
+      if (menuBg == null || isDarkColor(menuBg)) {
+        UIManager.put("Menu.background", new Color(50, 50, 50));
+      }
+      if (menuFg == null || (menuBg != null && isDarkColor(menuBg) && isDarkColor(menuFg))) {
+        UIManager.put("Menu.foreground", Color.WHITE);
+      }
+      UIManager.put("Menu.selectionBackground", new Color(60, 60, 60));
+      UIManager.put("Menu.selectionForeground", Color.WHITE);
+      
+      // Fix menu item colors
+      Color menuItemBg = UIManager.getColor("MenuItem.background");
+      Color menuItemFg = UIManager.getColor("MenuItem.foreground");
+      if (menuItemBg == null || isDarkColor(menuItemBg)) {
+        UIManager.put("MenuItem.background", new Color(50, 50, 50));
+      }
+      if (menuItemFg == null || (menuItemBg != null && isDarkColor(menuItemBg) && isDarkColor(menuItemFg))) {
+        UIManager.put("MenuItem.foreground", Color.WHITE);
+      }
+      UIManager.put("MenuItem.selectionBackground", new Color(60, 60, 60));
+      UIManager.put("MenuItem.selectionForeground", Color.WHITE);
+    }
+    
+    // Popup menu colors
+    Color popupBg = UIManager.getColor("PopupMenu.background");
+    if (popupBg == null || isDarkColor(popupBg)) {
+      UIManager.put("PopupMenu.background", new Color(50, 50, 50));
+      UIManager.put("PopupMenu.foreground", Color.WHITE);
+      UIManager.put("PopupMenu.borderColor", new Color(70, 70, 70));
+    }
+    
+    // Checkbox and radio button menu items
+    Color checkBoxMenuItemBg = UIManager.getColor("CheckBoxMenuItem.background");
+    if (checkBoxMenuItemBg == null || isDarkColor(checkBoxMenuItemBg)) {
+      UIManager.put("CheckBoxMenuItem.background", new Color(50, 50, 50));
+      UIManager.put("CheckBoxMenuItem.foreground", Color.WHITE);
+      UIManager.put("CheckBoxMenuItem.selectionBackground", new Color(60, 60, 60));
+      UIManager.put("CheckBoxMenuItem.selectionForeground", Color.WHITE);
+    }
+    
+    Color radioMenuItemBg = UIManager.getColor("RadioButtonMenuItem.background");
+    if (radioMenuItemBg == null || isDarkColor(radioMenuItemBg)) {
+      UIManager.put("RadioButtonMenuItem.background", new Color(50, 50, 50));
+      UIManager.put("RadioButtonMenuItem.foreground", Color.WHITE);
+      UIManager.put("RadioButtonMenuItem.selectionBackground", new Color(60, 60, 60));
+      UIManager.put("RadioButtonMenuItem.selectionForeground", Color.WHITE);
+    }
+  }
+
+  /**
+   * Checks if a color is dark (suitable for dark theme).
+   */
+  private static boolean isDarkColor(Color color) {
+    if (color == null) {
+      return false;
+    }
+    // Calculate luminance
+    double luminance = (0.299 * color.getRed() + 0.587 * color.getGreen() + 0.114 * color.getBlue()) / 255;
+    return luminance < 0.5;
+  }
+}
+