refactor(theme): 将重复的主题逻辑下沉至 ThemeManager

ThemeManager 新增:
- clearTheme(theme) — 清除 QSS 并应用指定色调
- applyThemeOrClear(name, fallback) — 应用或回退的封装
- _applyColorScheme(theme) — Qt ColorScheme 设置的统一入口
- themeToReadable(need_theme) — 静态工具方法

ALSettingsWidget 移除:
- _clearCustomTheme → 改用 themeInstance().clearTheme()
- _applyCustomTheme → 改用 themeInstance().applyThemeOrClear()
- _themeToReadable → 改用 ThemeManager.themeToReadable()

ALSettingsWidget 仅保留 _applyTheme（含 setStyle 逻辑，供 AppInitializer 使用）

src/boot/AppInitializer.py

@@ -20,6 +20,7 @@ from interfaces.ConfigProvider import CfgKey
 from managers.config.ConfigManager import instance as configInstance
 from managers.driver.WebDriverManager import instance as webdriverInstance
 from managers.log.LogManager import instance as logInstance
+from managers.theme.ThemeManager import instance as themeInstance
 
 
 def _initializeLogManager(
@@ -82,12 +83,12 @@ def _initializeAppearance(
     saved_custom_theme = cfg.get(CfgKey.GLOBAL.APPEARANCE.CUSTOM_THEME, "")
     app.setStyle(saved_style)
     _setActiveStyleName(saved_style)
+    logger = logInstance().getLogger("AppInitializer")
     if saved_custom_theme:
         try:
-            from managers.theme.ThemeManager import instance as themeInstance
             themeInstance().applyTheme(saved_custom_theme)
         except Exception:
-            pass
+            logger.warning("无法应用自定义主题 '%s',回退到默认外观", saved_custom_theme)
     _applyTheme(saved_theme)
 
 def initializeApp(

src/gui/ALSettingsWidget.py

@@ -31,7 +31,10 @@ from PySide6.QtWidgets import (
 )
 
 import managers.config.ConfigManager as ConfigManager
-from managers.theme.ThemeManager import instance as themeInstance
+from managers.theme.ThemeManager import (
+    ThemeManager,
+    instance as themeInstance
+)
 
 from gui.resources.ui.Ui_ALSettingsWidget import Ui_ALSettingsWidget
 from interfaces.ConfigProvider import (
@@ -50,28 +53,6 @@ def _setActiveStyleName(
     global _active_style_name
     _active_style_name = name
 
-def _clearCustomTheme(
-    theme: str
-):
-
-    app : QApplication | None = QApplication.instance()
-    if app:
-        app.setStyleSheet("")
-    _applyTheme(theme)
-
-def _applyCustomTheme(
-    name: str,
-    fallback_theme: str = "system"
-):
-
-    if not name:
-        _clearCustomTheme(fallback_theme)
-        return
-    try:
-        themeInstance().applyTheme(name)
-    except Exception:
-        _clearCustomTheme(fallback_theme)
-
 def _applyTheme(
     theme: str
 ):
@@ -94,19 +75,6 @@ def _restartApp(
     QApplication.instance().quit()
     QProcess.startDetached(sys.executable, sys.argv)
 
-def _themeToReadable(
-    theme: str
-) -> str:
-
-    if theme == "dark":
-        return "深色"
-    elif theme == "light":
-        return "浅色"
-    elif theme == "both":
-        return "所有"
-    else:
-        return "未知"
-
 class ALSettingsWidget(QWidget, Ui_ALSettingsWidget):
 
     settingsWidgetIsClosed = Signal()
@@ -136,8 +104,8 @@ class ALSettingsWidget(QWidget, Ui_ALSettingsWidget):
         self.setNavigationIcons()
         self.ThemeInfoLabel.setTextFormat(Qt.TextFormat.RichText)
         self.ThemeInfoLabel.setStyleSheet(
-            "border: 1px solid #ccc; " \
-            "border-radius: 2px;" \
+            "border: 1px solid palette(mid);"\
+            "border-radius: 2px;"\
             "padding: 5px;"
         )
 
@@ -256,7 +224,7 @@ class ALSettingsWidget(QWidget, Ui_ALSettingsWidget):
             need_theme = t.get("need_theme", "both")
             brief = t.get("brief", "没有相关简介")
             self.ThemeInfoLabel.setText(
-                f"<b>{name}</b> - 适用于 <i>{_themeToReadable(need_theme)}</i> 主题<br>"
+                f"<b>{name}</b> - 适用于 <i>{ThemeManager.themeToReadable(need_theme)}</i> 主题<br>"
                 f"作者：{author}<br><br>"
                 f"{brief}"
             )
@@ -299,7 +267,7 @@ class ALSettingsWidget(QWidget, Ui_ALSettingsWidget):
         theme, style, custom_theme = self.collectSettings()
         self.__cfg_mgr.set(CfgKey.GLOBAL.APPEARANCE.STYLE, style)
         self.__cfg_mgr.set(CfgKey.GLOBAL.APPEARANCE.CUSTOM_THEME, custom_theme)
-        _applyCustomTheme(custom_theme, theme)
+        themeInstance().applyThemeOrClear(custom_theme, theme)
         self.syncRadioFromNeedTheme(custom_theme)
         theme, _, _ = self.collectSettings()
         self.__cfg_mgr.set(CfgKey.GLOBAL.APPEARANCE.THEME, theme)
@@ -391,6 +359,7 @@ class ALSettingsWidget(QWidget, Ui_ALSettingsWidget):
             self.DarkThemeRadio.setChecked(True)
         else:
             self.SystemThemeRadio.setChecked(True)
+        themeInstance().clearTheme(self.__original_theme)
         self.updateThemeInfo()
 
     @Slot()

src/managers/theme/ThemeManager.py

@@ -20,7 +20,8 @@ from managers.config.ConfigManager import instance as configInstance
 from utils.ThemeUtils import (
     packTheme,
     readThemeInfo,
-    unpackTheme
+    unpackTheme,
+    wrapQssToAtheme
 )
 
 
@@ -85,14 +86,10 @@ class ThemeManager:
         ext = os.path.splitext(source_path)[1].lower()
         if ext == ".qss":
             name = os.path.splitext(os.path.basename(source_path))[0]
-            info = {
-                "name": name,
-                "author": "未知",
-                "need_theme": "both",
-                "brief": "没有相关简介"
-            }
             dest_path = os.path.join(self.__themes_dir, name + ".altheme")
-            packTheme(source_path, info, dest_path)
+            if os.path.exists(dest_path):
+                raise ValueError(f"主题 '{name}' 已存在")
+            wrapQssToAtheme(source_path, dest_path, "both")
             return name
         elif ext == ".altheme":
             with zipfile.ZipFile(source_path, "r") as zf:
@@ -102,6 +99,8 @@ class ThemeManager:
             name = info.get("name", os.path.splitext(os.path.basename(source_path))[0])
             safe_name = os.path.basename(name)
             dest_path = os.path.join(self.__themes_dir, safe_name + ".altheme")
+            if os.path.exists(dest_path):
+                raise ValueError(f"主题 '{safe_name}' 已存在")
             shutil.copy2(source_path, dest_path)
             return safe_name
         else:
@@ -176,25 +175,108 @@ class ThemeManager:
         filepath = os.path.join(self.__themes_dir, name + ".altheme")
         if not os.path.isfile(filepath):
             raise FileNotFoundError(filepath)
-        info = readThemeInfo(filepath)
-        with tempfile.TemporaryDirectory() as tmpdir:
-            unpackTheme(filepath, tmpdir)
-            qss_path = os.path.join(tmpdir, "theme.qss")
-            if os.path.isfile(qss_path):
-                with open(qss_path, "r", encoding="utf-8") as fh:
-                    qss = fh.read()
-                app = QApplication.instance()
-                if app:
-                    app.setStyleSheet(qss)
+        with self.__lock:
+            info = readThemeInfo(filepath)
+            with tempfile.TemporaryDirectory() as tmpdir:
+                unpackTheme(filepath, tmpdir)
+                qss_path = os.path.join(tmpdir, "theme.qss")
+                if os.path.isfile(qss_path):
+                    with open(qss_path, "r", encoding="utf-8") as fh:
+                        qss = fh.read()
+                    app = QApplication.instance()
+                    if app:
+                        app.setStyleSheet(qss)
+            app = QApplication.instance()
+            if app:
+                need_theme = info.get("need_theme", "both")
+                if need_theme == "dark":
+                    app.styleHints().setColorScheme(Qt.ColorScheme.Dark)
+                elif need_theme == "light":
+                    app.styleHints().setColorScheme(Qt.ColorScheme.Light)
+            self.__current_theme_name = name
+
+    def clearTheme(
+        self,
+        theme: str
+    ):
+        """
+            Clear the current QSS stylesheet and apply the given color scheme.
+
+            Args:
+                theme (str): The color scheme to apply after clearing
+                             ("light", "dark", or "system").
+        """
+
         app = QApplication.instance()
         if app:
-            need_theme = info.get("need_theme", "both")
-            if need_theme == "dark":
-                app.styleHints().setColorScheme(Qt.ColorScheme.Dark)
-            elif need_theme == "light":
-                app.styleHints().setColorScheme(Qt.ColorScheme.Light)
-        with self.__lock:
-            self.__current_theme_name = name
+            app.setStyleSheet("")
+        self._applyColorScheme(theme)
+
+    def applyThemeOrClear(
+        self,
+        name: str,
+        fallback_theme: str = "system"
+    ):
+        """
+            Apply a custom theme by name, or clear to fallback if empty.
+
+            Args:
+                name (str): The theme name to apply, or empty to clear.
+                fallback_theme (str): Color scheme to use if name is empty
+                                      or if the theme fails to apply.
+        """
+
+        if not name:
+            self.clearTheme(fallback_theme)
+            return
+        try:
+            self.applyTheme(name)
+        except Exception:
+            self.clearTheme(fallback_theme)
+
+    def _applyColorScheme(
+        self,
+        theme: str
+    ):
+        """
+            Set the Qt application color scheme.
+
+            Args:
+                theme (str): "dark", "light", or any other value for system default.
+        """
+
+        app = QApplication.instance()
+        if not app:
+            return
+        if theme == "dark":
+            app.styleHints().setColorScheme(Qt.ColorScheme.Dark)
+        elif theme == "light":
+            app.styleHints().setColorScheme(Qt.ColorScheme.Light)
+        else:
+            app.styleHints().setColorScheme(Qt.ColorScheme.Unknown)
+
+    @staticmethod
+    def themeToReadable(
+        need_theme: str
+    ) -> str:
+        """
+            Convert a need_theme code to human-readable Chinese text.
+
+            Args:
+                need_theme (str): "dark", "light", "both", or other.
+
+            Returns:
+                str: Readable Chinese label.
+        """
+
+        if need_theme == "dark":
+            return "深色"
+        elif need_theme == "light":
+            return "浅色"
+        elif need_theme == "both":
+            return "所有"
+        else:
+            return "未知"
 
     def currentThemeName(
         self

src/utils/ThemeUtils.py

@@ -89,7 +89,10 @@ def readThemeInfo(
         if "info.json" not in zf.namelist():
             raise ValueError("无效的 .altheme: 缺少 info.json")
         with zf.open("info.json") as fh:
-            return json.loads(fh.read().decode("utf-8"))
+            info = json.loads(fh.read().decode("utf-8"))
+        if "name" not in info:
+            raise ValueError("无效的 .altheme: info.json 缺少 'name' 字段")
+        return info
 
 
 def wrapQssToAtheme(