[nongnu] elpa/auto-dim-other-buffers c9fe23d03c 79/82: Allow configuring which faces to alter; not just the ‘default’

[ELPA Syncer]

branch: elpa/auto-dim-other-buffers
commit c9fe23d03ccb21713395429bd554689b61973b49
Author: Michal Nazarewicz <mina86@mina86.com>
Commit: Michal Nazarewicz <mina86@mina86.com>

    Allow configuring which faces to alter; not just the ‘default’
    
    Introduce ‘auto-dim-other-buffers-affected-faces’ list which specifies
    which faces should have relative remapping added and what that
    remapping should be.  Previously, adob would only affect the ‘default’
    face adding ‘auto-dim-other-buffers-face’ remapping to it.  With this
    new variable, other faces can be configured to be changed as well.
    
    For example, ‘org-block’ in Leuven theme uses light yellow background
    which previously would stay yellow in dimmed windows.  Now, since
    ‘org-block’ is included in ‘auto-dim-other-buffers-affected-faces’,
    it’s dimmed just like the rest of the window.
    
    Note that no other faces are not affected by default so depending on
    mode and colour theme various parts of the buffer may remain undimmed.
    If that’s not desired, faces responsible for those colours need to be
    manually added to the ‘auto-dim-other-buffers-affected-faces’ list.
    
    Furthermore, since the list allows to set different remappings for
    different faces, how each face is dimmed can be configured separately
    as well by creating dimmed faces for each such face.
    
    Fixes: https://github.com/mina86/auto-dim-other-buffers.el/issues/24
---
 auto-dim-other-buffers.el | 127 ++++++++++++++++++++++++++++++++++------------
 1 file changed, 94 insertions(+), 33 deletions(-)

diff --git a/auto-dim-other-buffers.el b/auto-dim-other-buffers.el
index f7fc4a5036..0cf17f2a30 100644
--- a/auto-dim-other-buffers.el
+++ b/auto-dim-other-buffers.el
@@ -70,9 +70,16 @@
 
 (defface auto-dim-other-buffers-face
   '((((background light)) :background "#eff") (t :background "#122"))
-  "Face (presumably dimmed somehow) for non-selected window."
+  "Face with a (presumably) dimmed background for non-selected window.
+
+By default the face is applied to, among others, the ‘default’
+face and is intended to affect the background of the non-selected
+windows.  Which faces are actually modified is configured by the
+‘auto-dim-other-buffers-affected-faces’ variable."
   :group 'auto-dim-other-buffers)
 
+(defvar auto-dim-other-buffers-affected-faces) ; Forward declaration.
+
 (defcustom auto-dim-other-buffers-dim-on-focus-out t
   "Whether to dim all windows when frame looses focus."
   :type 'boolean
@@ -91,14 +98,6 @@ If t, the code will run in ‘auto dim other window’ mode 
(hence
 operate on windows, Emacs must support :filtered face predicate
 which has been added in Emacs 27.")
 
-(defconst adob--remap-face
-  (if adob--adow-mode
-      '(:filtered (:window adob--dim t) auto-dim-other-buffers-face)
-    'auto-dim-other-buffers-face)
-  "Face to use when adding relative face remapping.
-Depending on whether Emacs supports :filtered predicate, this
-will or will not use it.  See ‘adob--adow-mode’.")
-
 (defvar adob--last-buffer nil
   "Last selected buffer, i.e. buffer which is currently not dimmed.")
 (defvar adob--last-window nil
@@ -114,32 +113,76 @@ dimmed.  In addition to that, outside of adow-mode (see
       (run-hook-with-args-until-success
        'auto-dim-other-buffers-never-dim-buffer-functions buffer)))
 
+
 (defvar-local adob--face-mode-remapping nil
   "Current face remapping cookie for `auto-dim-other-buffers-mode'.")
 (put 'adob--face-mode-remapping 'permanent-local nil)
 
-(defun adob--remap-face (buffer object)
-  "Make sure face remapping is active in BUFFER unless its never-dim.
+(defun adob--remap-add-relative ()
+  "Adds all necessary relative face mappings.
+Updates ‘adob--face-mode-remapping’ variable accordingly."
+  (let ((make-face (if adob--adow-mode
+                       (lambda (face) `(:filtered (:window adob--dim t) ,face))
+                     #'identity)))
+    (setq adob--face-mode-remapping
+          (mapcar (lambda (spec)
+                    (face-remap-add-relative (car spec)
+                                             (funcall make-face (cdr spec))))
+                  auto-dim-other-buffers-affected-faces))))
+
+(defun adob--remap-remove-relative ()
+  "Remove all relative mappings that we’ve added.
+List of existing mappings is taken from ‘adob--face-mode-remapping’
+variable which is set to nil afterwards."
+  (mapc #'face-remap-remove-relative adob--face-mode-remapping)
+  (setq adob--face-mode-remapping nil))
+
+(defun adob--remap-cycle-all ()
+  "Removes and re-adds face remappings in all buffers when they exist.
+If ‘auto-dim-other-buffers-mode’ is enabled, this function needs
+to be called after ‘auto-dim-other-buffers-affected-faces’
+variable is changed to update state of all affected buffers.
+Note that it is called automatically as necessary when setting
+than variable via Customise."
+  (save-current-buffer
+    (mapc (lambda (buffer)
+            ;; It’s tempting to read the value of the variable and not bother
+            ;; with the buffer if the value is nil since in that case the
+            ;; buffer is presumably never-dim and thus we won’t remap any
+            ;; faces in it.  There is one corner case when this is not true
+            ;; however.  If at one point user set list of faces to affect to
+            ;; nil the list of remapping will be nil as well and when user
+            ;; changes the variable we’ll need to add remappings.
+            (when (local-variable-p 'adob--face-mode-remapping buffer)
+              (set-buffer buffer)
+              (let ((had-none (not adob--face-mode-remapping)))
+                (adob--remap-remove-relative)
+                (unless (adob--never-dim-p buffer)
+                  (adob--remap-add-relative))
+                (unless (eq had-none (not adob--face-mode-remapping))
+                  (force-window-update buffer)))))
+          (buffer-list))))
+
+(defun adob--remap-faces (buffer object)
+  "Make sure face remappings are active in BUFFER unless its never-dim.
 
 Does not preserve current buffer.
 
 If BUFFER is never-dim (as determined by ‘adob--never-dim-p’),
-remove adob face remapping (if present) from BUFFER.  Otherwise,
-make sure the remapping is active by adding it if it’s missing.
+remove adob face remappings from it.  Otherwise, make sure the
+remappings are active by adding them if it’s missing.
 
 If face remapping had to be changed, force update of OBJECT,
 which can be a window or a buffer.
 
-Return non-nil if remapping has been added to BUFFER."
+Return non-nil if remappings have been added to BUFFER."
   (let ((wants (not (adob--never-dim-p buffer)))
         (has (buffer-local-value 'adob--face-mode-remapping buffer)))
     (when (eq wants (not has))
       (set-buffer buffer)
-      (setq adob--face-mode-remapping
-            (if wants
-                (face-remap-add-relative 'default adob--remap-face)
-              (face-remap-remove-relative adob--face-mode-remapping)
-              nil))
+      (if wants
+          (adob--remap-add-relative)
+        (adob--remap-remove-relative))
       (force-window-update object)
       wants)))
 
@@ -148,10 +191,8 @@ Return non-nil if remapping has been added to BUFFER."
 This is intended as an advice around ‘kill-all-local-variables’
 function which removes all buffer face remapping which is
 something we don’t want."
-  (unless (prog1 (not adob--face-mode-remapping)
-          (funcall kill))
-    (setq adob--face-mode-remapping
-          (face-remap-add-relative 'default adob--remap-face))
+  (when (prog1 adob--face-mode-remapping (funcall kill))
+    (adob--remap-add-relative)
     nil))
 
 (defun adob--unmap-face (buffer object)
@@ -163,8 +204,7 @@ If face remapping had to be changed, force update of OBJECT 
which
 can be a window or a buffer."
   (when (buffer-local-value 'adob--face-mode-remapping buffer)
     (set-buffer buffer)
-    (face-remap-remove-relative adob--face-mode-remapping)
-    (setq adob--face-mode-remapping nil)
+    (adob--remap-remove-relative)
     (force-window-update object)))
 
 (defun adob--dim-buffer (buffer &optional except-in)
@@ -175,7 +215,7 @@ Does not preserve current buffer.
 EXCEPT-IN only works if the code is running in adow mode (see
 ‘adob--adow-mode’) and it works by deactivating the dimmed face
 in specified window."
-  (when (adob--remap-face buffer buffer)
+  (when (adob--remap-faces buffer buffer)
     (dolist (wnd (and adob--adow-mode
                       (get-buffer-window-list buffer 'n 'visible)))
       (set-window-parameter wnd 'adob--dim (not (eq wnd except-in))))))
@@ -224,7 +264,7 @@ Dim previously selected window if selection has changed."
             (adob--dim-buffer adob--last-buffer wnd))
           (setq adob--last-buffer buf)
           (if adob--adow-mode
-              (adob--remap-face buf buf)
+              (adob--remap-faces buf buf)
             (adob--unmap-face buf buf)))))))
 
 (defun adob--rescan-windows ()
@@ -242,12 +282,12 @@ Dim previously selected window if selection has changed."
                      (set-window-parameter wnd 'adob--dim new)
                      (force-window-update wnd)))
                  ;; In adow-mode, make sure that the buffer has remapped faces.
-                 (adob--remap-face buf wnd))
+                 (adob--remap-faces buf wnd))
                 ;; Outside of adow-mode, add or remove face remapping depending
                 ;; on whether current buffer selected buffer or not.
                 ((eq buf selected-buffer)
                  (adob--unmap-face buf wnd))
-                ((adob--remap-face buf wnd))))))))
+                ((adob--remap-faces buf wnd))))))))
 
 (defun adob--buffer-list-update-hook ()
   "React to buffer list changes.
@@ -340,10 +380,10 @@ and frame’s doesn’t have focus."
   "Visually makes windows without focus less prominent.
 
 Windows without input focus are made to look less prominent by
-applying ‘auto-dim-other-buffers-face’ to them.  With many
-windows in a frame, the idea is that this mode helps recognise
-which is the selected window by providing a non-intrusive but
-still noticeable visual indicator.
+applying ‘auto-dim-other-buffers-face’ to them.  With many windows
+in a frame, the idea is that this mode helps recognise which is
+the selected window by providing a non-intrusive but still
+noticeable visual indicator.
 
 Note that despite it’s name, since Emacs 27 this mode operates
 on *windows* rather than buffers.  In older versions of Emacs, if
@@ -422,6 +462,27 @@ update display state of all affected buffers."
              (adob--initialize)))
          value))
 
+(defcustom auto-dim-other-buffers-affected-faces
+  '((default   . auto-dim-other-buffers-face)
+    (org-block . auto-dim-other-buffers-face))
+  "A list of faces affected when dimming a window.
+
+The list consists of (FACE . REMAP-FACE) pairs where FACE is an
+existing face which should be affected when dimming a window and
+REMAP-FACE is remapping which should be added to it.
+
+Typically, REMAP-FACE is ‘auto-dim-other-buffers-face’.  It is
+used when the background of a FACE needs to be dimmed.
+
+Changing this variable outside of customize does not update
+display state of affected buffers."
+  :type '(list (cons face face))
+  :group 'auto-dim-other-buffers
+  :set (lambda (symbol value)
+         (set-default symbol value)
+         (when auto-dim-other-buffers-mode
+           (adob--remap-cycle-all))))
+
 
 (provide 'auto-dim-other-buffers)