[ThemeManager] Extract system theme dir path resolution to helper, use it in default palette fetching

Took 8 minutes

cockatrice/src/interface/palette_editor/palette_editor_dialog.cpp

@@ -176,8 +176,8 @@ void PaletteEditorDialog::retranslateUi()
     titleLabel->setText(tr("<b>Palette Editor</b> &nbsp;·&nbsp; %1").arg(themeName));
 
     // Revert button only makes sense when the theme ships default palette files
-    const bool hasDefault = PaletteConfig::fromDefault(themeDirPath, "Light").hasPalette() ||
+    const bool hasDefault = ThemeManager::loadDefaultPaletteConfig(themeDirPath, themeName, "Light").hasPalette() ||
-                            PaletteConfig::fromDefault(themeDirPath, "Dark").hasPalette();
+                            ThemeManager::loadDefaultPaletteConfig(themeDirPath, themeName, "Dark").hasPalette();
     revertButton->setEnabled(hasDefault);
     if (!hasDefault) {
         revertButton->setToolTip(tr("This theme ships no default palette files"));
@@ -211,7 +211,7 @@ void PaletteEditorDialog::loadSchemes()
         PaletteConfig cfg = PaletteConfig::fromScheme(themeDirPath, scheme);
 
         if (!cfg.hasPalette()) {
-            cfg = PaletteConfig::fromDefault(themeDirPath, scheme);
+            cfg = ThemeManager::loadDefaultPaletteConfig(themeDirPath, themeName, scheme);
         }
 
         if (!cfg.hasPalette()) {
@@ -309,7 +309,7 @@ void PaletteEditorDialog::onReset()
 
 void PaletteEditorDialog::onRevertToDefault()
 {
-    PaletteConfig def = PaletteConfig::fromDefault(themeDirPath, loadedScheme);
+    PaletteConfig def = ThemeManager::loadDefaultPaletteConfig(themeDirPath, themeName, loadedScheme);
     if (!def.hasPalette()) {
         QMessageBox::information(this, tr("No default found"),
                                  tr("No default palette file found for the \"%1\" scheme.").arg(loadedScheme));

cockatrice/src/interface/theme_manager.cpp

@@ -137,6 +137,20 @@ bool ThemeManager::isBuiltInTheme()
     return themeName == NONE_THEME_NAME || themeName == FUSION_THEME_NAME;
 }
 
+// System (read-only) themes location, relative to the application binary.
+static QString systemThemesBasePath()
+{
+    QString base = qApp->applicationDirPath();
+#ifdef Q_OS_MAC
+    base += "/../Resources/themes";
+#elif defined(Q_OS_WIN)
+    base += "/themes";
+#else // linux
+    base += "/../share/cockatrice/themes";
+#endif
+    return base;
+}
+
 QStringMap &ThemeManager::getAvailableThemes()
 {
     QDir dir;
@@ -157,15 +171,7 @@ QStringMap &ThemeManager::getAvailableThemes()
     }
 
     // load themes from cockatrice system dir
-    dir.setPath(qApp->applicationDirPath() +
+    dir.setPath(systemThemesBasePath());
-#ifdef Q_OS_MAC
-                "/../Resources/themes"
-#elif defined(Q_OS_WIN)
-                "/themes"
-#else // linux
-                "/../share/cockatrice/themes"
-#endif
-    );
 
     for (QString themeName : dir.entryList(QDir::AllDirs | QDir::NoDotAndDotDot, QDir::Name)) {
         if (!availableThemes.contains(themeName)) {
@@ -242,6 +248,20 @@ bool ThemeManager::savePaletteConfig(const QString &themeDirPath, const QString
     return true;
 }
 
+PaletteConfig ThemeManager::loadDefaultPaletteConfig(const QString &themeDirPath,
+                                                     const QString &themeName,
+                                                     const QString &colorScheme)
+{
+    PaletteConfig cfg = PaletteConfig::fromDefault(themeDirPath, colorScheme);
+    if (!cfg.hasPalette()) {
+        // The shipped default may live in the system theme directory rather
+        // than the resolved (user) theme directory, so built-in themes still
+        // get their curated defaults.
+        cfg = PaletteConfig::fromDefault(QDir(systemThemesBasePath()).absoluteFilePath(themeName), colorScheme);
+    }
+    return cfg;
+}
+
 void ThemeManager::setColorScheme(const QString &scheme)
 {
     const QString dirPath = getAvailableThemes().value(SettingsCache::instance().getThemeName());
@@ -353,7 +373,7 @@ void ThemeManager::themeChangedSlot()
     // ── Load palette: custom first, then theme default ────────────────────
     PaletteConfig palette = PaletteConfig::fromScheme(dirPath, activeScheme);
     if (!palette.hasPalette()) {
-        palette = PaletteConfig::fromDefault(dirPath, activeScheme);
+        palette = ThemeManager::loadDefaultPaletteConfig(dirPath, themeName, activeScheme);
     }
 
     applyStyleAndPalette(themeName, themeCfg, palette, activeScheme);

cockatrice/src/interface/theme_manager.h

@@ -76,6 +76,10 @@ public:
     // Load/save per-scheme palette colors
     static PaletteConfig loadPaletteConfig(const QString &themeDirPath, const QString &colorScheme);
     static bool savePaletteConfig(const QString &themeDirPath, const QString &colorScheme, const PaletteConfig &cfg);
+    // Load the theme's shipped default palette, falling back to the system
+    // theme directory when it is absent from the resolved (user) directory.
+    static PaletteConfig
+    loadDefaultPaletteConfig(const QString &themeDirPath, const QString &themeName, const QString &colorScheme);
     void setColorScheme(const QString &scheme);
 
     void reloadCurrentTheme();