refactor(theme): 将重复的主题逻辑下沉至 ThemeUtils，消除 validateTheme 职责过重

src/managers/theme/ThemeManager.py

@@ -21,6 +21,7 @@ from interfaces.ConfigProvider import CfgKey
 from managers.config.ConfigManager import instance as configInstance
 from managers.log.LogManager import instance as logInstance
 from utils.ThemeUtils import (
+    readThemeInfo,
     readThemeQss,
     validateTheme,
     wrapQssToAtheme
@@ -79,17 +80,21 @@ class ThemeManager:
         else:
             return Qt.ColorScheme.Unknown
 
-    def themesDir(
-        self
-    ) -> str:
+    def _deleteThemeFile(
+        self,
+        name: str
+    ):
         """
-            Get the themes directory path.
+            Delete a theme file in the themes storage directory.
 
-            Returns:
-                str: The absolute path to the themes storage directory.
+            The caller must hold self.__lock before invoking this method.
+
+            **This method ONLY deletes the file**.
         """
 
-        return self.__themes_dir
+        filepath = os.path.join(self.__themes_dir, name + ".altheme")
+        if os.path.isfile(filepath):
+            os.remove(filepath)
 
     def _resolveDestPath(
         self,
@@ -121,7 +126,7 @@ class ThemeManager:
             existing_info = validateTheme(default_path)
             existing_author = existing_info.get("author", "")
         except Exception:
-            self._removeThemeFile(theme_name)  # caller holds the lock
+            self._deleteThemeFile(theme_name)  # caller holds the lock
             raise ValueError(
                 f"主题 '{theme_name}' 已存在但无法通过验证, 已清理该主题文件"
             )
@@ -139,6 +144,18 @@ class ThemeManager:
             )
         return alt_path
 
+    def themesDir(
+        self
+    ) -> str:
+        """
+            Get the themes directory path.
+
+            Returns:
+                str: The absolute path to the themes storage directory.
+        """
+
+        return self.__themes_dir
+
     def importTheme(
         self,
         source_path: str
@@ -164,16 +181,16 @@ class ThemeManager:
 
         if not os.path.isfile(source_path):
             raise FileNotFoundError(source_path)
-        ext = os.path.splitext(source_path)[1].lower()
+        base_name, ext = os.path.splitext(os.path.basename(source_path))
+        ext = ext.lower()
         with self.__lock:
             if ext == ".qss":
-                name = os.path.splitext(os.path.basename(source_path))[0]
-                dest_path = self._resolveDestPath(name, "未知作者")
+                dest_path = self._resolveDestPath(base_name, "未知作者")
                 wrapQssToAtheme(source_path, dest_path, "both")
                 return os.path.splitext(os.path.basename(dest_path))[0]
             elif ext == ".altheme":
                 info = validateTheme(source_path)
-                name = info.get("name", os.path.splitext(os.path.basename(source_path))[0])
+                name = info.get("name", base_name)
                 safe_name = os.path.basename(name)
                 new_author = info.get("author", "")
                 dest_path = self._resolveDestPath(safe_name, new_author)
@@ -203,7 +220,7 @@ class ThemeManager:
             if filename.endswith(".altheme"):
                 filepath = os.path.join(self.__themes_dir, filename)
                 try:
-                    info = validateTheme(filepath, check_qss=False)  # skip QSS read for list scan
+                    info = validateTheme(filepath)
                     name = info.get("name", "")
                     author = info.get("author", "")
                     key = (name, author)
@@ -225,26 +242,6 @@ class ThemeManager:
                 )
         return themes
 
-    def _removeThemeFile(
-        self,
-        name: str
-    ):
-        """
-            Remove a theme file without locking.
-
-            The caller must hold self.__lock before invoking this method.
-        """
-
-        filepath = os.path.join(self.__themes_dir, name + ".altheme")
-        if os.path.isfile(filepath):
-            os.remove(filepath)
-            if self.__current_theme_name == name:
-                self.__current_theme_name = ""
-                saved_theme = configInstance().get(
-                    CfgKey.GLOBAL.APPEARANCE.THEME, "system"
-                )
-                self.clearTheme(saved_theme)
-
     def removeTheme(
         self,
         name: str
@@ -253,14 +250,21 @@ class ThemeManager:
             Remove a theme by name.
 
             If the removed theme is currently active, clears the QSS
-            stylesheet from the application.
+            stylesheet from the application and reverts to the saved
+            colour scheme.
 
             Args:
                 name (str): The theme name to remove.
         """
 
         with self.__lock:
-            self._removeThemeFile(name)
+            self._deleteThemeFile(name)
+            if self.__current_theme_name == name:
+                self.__current_theme_name = ""
+                saved_theme = configInstance().get(
+                    CfgKey.GLOBAL.APPEARANCE.THEME, "system"
+                )
+                self.clearTheme(saved_theme)
 
     def applyTheme(
         self,
@@ -284,7 +288,7 @@ class ThemeManager:
         if not os.path.isfile(filepath):
             raise FileNotFoundError(filepath)
         with self.__lock:
-            info = validateTheme(filepath)
+            info = readThemeInfo(filepath)
             qss = readThemeQss(filepath)
             app = QApplication.instance()
             if app:

src/utils/ThemeUtils.py

@@ -68,17 +68,20 @@ def readThemeInfo(
     altheme_path: str
 ) -> dict:
     """
-        Read only the info.json metadata from a .altheme file.
+        Read and validate the info.json metadata from a .altheme file.
+
+        Verifies that all required fields (name, author, need_theme, brief)
+        are present with valid values.
 
         Args:
             altheme_path (str): Path to the .altheme file.
 
         Returns:
-            dict: The theme metadata dictionary.
+            dict: The validated theme metadata dictionary.
 
         Raises:
             FileNotFoundError: If altheme_path does not exist.
-            ValueError: If the .altheme does not contain info.json.
+            ValueError: If info.json is missing or any field is invalid.
     """
 
     if not os.path.isfile(altheme_path):
@@ -87,76 +90,14 @@ 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:
-            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 readThemeQss(
-    altheme_path: str
-) -> str:
-    """
-        Read the theme.qss content directly from a .altheme archive.
-
-        Args:
-            altheme_path (str): Path to the .altheme file.
-
-        Returns:
-            str: The QSS stylesheet content.
-
-        Raises:
-            FileNotFoundError: If altheme_path does not exist.
-            ValueError: If theme.qss is missing from the archive.
-    """
-
-    if not os.path.isfile(altheme_path):
-        raise FileNotFoundError(altheme_path)
-    with zipfile.ZipFile(altheme_path, "r") as zf:
-        if "theme.qss" not in zf.namelist():
-            raise ValueError("无效的 .altheme: 缺少 theme.qss")
-        return zf.read("theme.qss").decode("utf-8")
-
-def validateTheme(
-    altheme_path: str,
-    check_qss: bool = True
-) -> dict:
-    """
-        Validate a .altheme file and return its metadata.
-
-        Checks that info.json and theme.qss both exist, info.json
-        contains all required fields with valid values, and theme.qss
-        is a non-empty entry in the archive.
-
-        Args:
-            altheme_path (str): Path to the .altheme file.
-            check_qss (bool): If False, skip theme.qss existence and
-                              content checks (for list-only operations).
-
-        Returns:
-            dict: The validated theme metadata dictionary.
-
-        Raises:
-            FileNotFoundError: If altheme_path does not exist.
-            ValueError: If validation fails for any reason.
-    """
-
-    if not os.path.isfile(altheme_path):
-        raise FileNotFoundError(altheme_path)
-    with zipfile.ZipFile(altheme_path, "r") as zf:
-        names = zf.namelist()
-        if "info.json" not in names:
-            raise ValueError("无效的 .altheme: 缺少 info.json")
-        if "theme.qss" not in names:
-            raise ValueError("无效的 .altheme: 缺少 theme.qss")
-        info_bytes = zf.read("info.json")
-        qss_bytes = zf.read("theme.qss") if check_qss else None  # skip QSS read when only listing
-    try:
-        info = json.loads(info_bytes.decode("utf-8"))
-    except (json.JSONDecodeError, UnicodeDecodeError) as e:
-        raise ValueError(f"无效的 .altheme: info.json 解析失败 — {e}")
+            try:
+                info = json.loads(fh.read().decode("utf-8"))
+            except (json.JSONDecodeError, UnicodeDecodeError) as e:
+                raise ValueError(f"无效的 .altheme: info.json 解析失败 — {e}")
     if "name" not in info or not isinstance(info.get("name"), str) or not info["name"].strip():
         raise ValueError("无效的 .altheme: info.json 缺少有效的 'name' 字段")
-    # reject blank author so info.json does not drift from the "未知作者" filename fallback
+    # reject blank author so that info.json does not drift from the
+    # "未知作者" filename fallback used by wrapQssToAtheme
     if ("author" not in info or not isinstance(info.get("author"), str)
             or not info["author"].strip()):
         raise ValueError("无效的 .altheme: info.json 缺少有效的 'author' 字段")
@@ -168,8 +109,58 @@ def validateTheme(
         )
     if "brief" not in info or not isinstance(info.get("brief"), str):
         raise ValueError("无效的 .altheme: info.json 缺少有效的 'brief' 字段")
-    if check_qss and not qss_bytes.strip():
+    return info
+
+def readThemeQss(
+    altheme_path: str
+) -> str:
+    """
+        Read the theme.qss content from a .altheme archive.
+
+        Args:
+            altheme_path (str): Path to the .altheme file.
+
+        Returns:
+            str: The non-empty QSS stylesheet content.
+
+        Raises:
+            FileNotFoundError: If altheme_path does not exist.
+            ValueError: If theme.qss is missing or empty.
+    """
+
+    if not os.path.isfile(altheme_path):
+        raise FileNotFoundError(altheme_path)
+    with zipfile.ZipFile(altheme_path, "r") as zf:
+        if "theme.qss" not in zf.namelist():
+            raise ValueError("无效的 .altheme: 缺少 theme.qss")
+        qss = zf.read("theme.qss").decode("utf-8")
+    if not qss.strip():
         raise ValueError("无效的 .altheme: theme.qss 为空")
+    return qss
+
+def validateTheme(
+    altheme_path: str
+) -> dict:
+    """
+        Fully validate a .altheme file and return its metadata.
+
+        Delegates info validation to readThemeInfo and QSS validation
+        to readThemeQss, then additionally checks that theme.qss is
+        non-empty.
+
+        Args:
+            altheme_path (str): Path to the .altheme file.
+
+        Returns:
+            dict: The validated theme metadata dictionary.
+
+        Raises:
+            FileNotFoundError: If altheme_path does not exist.
+            ValueError: If validation fails for any reason.
+    """
+
+    info = readThemeInfo(altheme_path)
+    readThemeQss(altheme_path)  # validates existence and non-empty
     return info
 
 def wrapQssToAtheme(