refactor: ui-theme: improve theme switching and persistence

Remove unnecessary comments and whitespace, streamline theme
switching logic, and update keybinding function for theme switching.
Add eval-when-compile for org-dir variable. Improve error messaging
and conditional checks for theme persistence.

1 files changed, 10 insertions, 17 deletions

diff --git a/modules/ui-theme.el b/modules/ui-theme.el
index d6eaf404..1575257a 100644
--- a/modules/ui-theme.el
+++ b/modules/ui-theme.el
@@ -17,7 +17,9 @@
 
 ;;; Code:
 
-(require 'user-constants)  ;; For org-dir
+(require 'user-constants)
+
+(eval-when-compile (defvar org-dir))
 
 ;; ----------------------------------- Themes ----------------------------------
 ;; theme choices and settings
@@ -32,35 +34,30 @@
 
 (defun cj/switch-themes ()
   "Function to switch themes and save chosen theme name for persistence.
-
 Unloads any other applied themes before applying the chosen theme."
   (interactive)
-  (let ((chosentheme ""))
-    (setq chosentheme
-          (completing-read "Load custom theme: "
-                           (mapcar #'symbol-name
-                                   (custom-available-themes))))
+  (let ((chosentheme (completing-read "Load custom theme: "
+                                      (mapcar #'symbol-name
+                                              (custom-available-themes)))))
     (mapc #'disable-theme custom-enabled-themes)
     (load-theme (intern chosentheme) t))
   (cj/save-theme-to-file))
 
-(global-set-key (kbd "M-L") 'cj/switch-themes)
+(keymap-global-set "M-L" #'cj/switch-themes)
 
 ;; ----------------------------- Theme Persistence -----------------------------
 ;; persistence utility functions used by switch themes.
 
 (defvar theme-file (concat org-dir "emacs-theme.persist")
   "The location of the file to persist the theme name.
-
 If you want your theme change to persist across instances, put this in a
 directory that is sync'd across machines with this configuration.")
 
 (defvar fallback-theme-name "modus-vivendi"
   "The name of the theme to fallback on.
-
-This is used then there's no file, or the theme name doesn't match
+This is used when there's no file, or the theme name doesn't match
 any of the installed themes. This should be a built-in theme. If theme name is
-'nil', there will be no theme.")
+`nil', there will be no theme.")
 
 (defun cj/read-file-contents (filename)
   "Read FILENAME and return its content as a string.
@@ -73,7 +70,6 @@ If FILENAME isn't readable, return nil."
 
 (defun cj/write-file-contents (content filename)
   "Write CONTENT to FILENAME.
-
 If FILENAME isn't writeable, return nil. If successful, return t."
   (when (file-writable-p filename)
     (condition-case err
@@ -88,7 +84,6 @@ If FILENAME isn't writeable, return nil. If successful, return t."
 
 (defun cj/get-active-theme-name ()
   "Return the name of the active UI theme as a string.
-
 Returns fallback-theme-name if no theme is active."
   (if custom-enabled-themes
       (symbol-name (car custom-enabled-themes))
@@ -96,20 +91,18 @@ Returns fallback-theme-name if no theme is active."
 
 (defun cj/save-theme-to-file ()
   "Save the string representing the current theme to the theme-file."
-  (if (equal (cj/write-file-contents (cj/get-active-theme-name) theme-file) nil)
+  (if (not (cj/write-file-contents (cj/get-active-theme-name) theme-file))
       (message "Cannot save theme: %s is unwriteable" theme-file)
     (message "%s theme saved to %s" (cj/get-active-theme-name) theme-file)))
 
 (defun cj/load-fallback-theme (msg)
   "Display MSG and load ui-theme fallback-theme-name.
-
 Used to handle errors with loading persisted theme."
   (message "%s Loading fallback theme %s" msg fallback-theme-name)
   (load-theme (intern fallback-theme-name) t))
 
 (defun cj/load-theme-from-file ()
   "Apply the theme name contained in theme-file as the active UI theme.
-
 If the theme is nil, it disables all current themes. If an error occurs
 loading the file name, the fallback-theme-name is applied and saved."
   (let ((theme-name (cj/read-file-contents theme-file)))