X-Git-Url: https://code.delx.au/gnu-emacs-elpa/blobdiff_plain/894174003d99e06c3206001945dbca40e4830b06..fbcf9fca51b52cc848164c0dd072b2aec77a165f:/beacon.el

diff --git a/beacon.el b/beacon.el
index 34dba38ac..8a997a1c5 100644
--- a/beacon.el
+++ b/beacon.el
@@ -6,7 +6,7 @@
 ;; URL: https://github.com/Malabarba/beacon
 ;; Keywords: convenience
 ;; Version: 0.1
-;; Package-Requires: ((cl-lib "0.5"))
+;; Package-Requires: ((seq "1.9"))
 
 ;; This program is free software; you can redistribute it and/or modify
 ;; it under the terms of the GNU General Public License as published by
@@ -28,7 +28,7 @@
 
 ;;; Code:
 
-(require 'cl-lib)
+(require 'seq)
 
 (defgroup beacon nil
   "Customization group for beacon."
@@ -71,9 +71,17 @@ movement distance (in lines) that triggers a beacon blink."
   "Size of the beacon in characters."
   :type 'number)
 
-(defcustom beacon-brightness 0.4
-  "Brightness as a float between 0 and 1."
-  :type 'number)
+(defcustom beacon-color 0.5
+  "Color of the beacon.
+This can be a string or a number.
+
+If it is a number, the color is taken to be white or
+black (depending on the current theme's background) and this
+number is a float between 0 and 1 specifing the brightness.
+
+If it is a string, it is a color name or specification,
+e.g. \"#666600\"."
+  :type '(choice number color))
 
 
 ;;; Overlays
@@ -86,9 +94,39 @@ movement distance (in lines) that triggers a beacon blink."
     (overlay-put ov 'beacon t)
     (push ov beacon--ovs)))
 
+(defun beacon--ov-put-after-string (overlay colors)
+  "Add an after-string property to OVERLAY.
+The property's value is a string of spaces with background
+COLORS applied to each one."
+  (if (not colors)
+      (delete-overlay overlay)
+    (overlay-put overlay 'beacon-colors colors)
+    (overlay-put overlay 'after-string
+                 (propertize
+                  (mapconcat (lambda (c) (propertize " " 'face (list :background c)))
+                             colors
+                             "")
+                  'cursor 1000))))
+
+(defun beacon--after-string-overlay (colors)
+  "Put an overlay at point with an after-string property.
+The property's value is a string of spaces with background
+COLORS applied to each one."
+  (let ((ov (make-overlay (point) (point)))
+        ;; The after-string must not be longer than the remaining columns from
+        ;; point to right window-end else it will be wrapped around (assuming
+        ;; truncate-lines is nil) introducing an ugly wrap-around for a
+        ;; fraction of a second.
+        (colors (seq-take colors (- (window-width) (current-column)))))
+    (beacon--ov-put-after-string ov colors)
+    (overlay-put ov 'beacon t)
+    (push ov beacon--ovs)))
+
 (defun beacon--ov-at-point ()
-  (car (cl-member-if (lambda (o) (overlay-get o 'beacon))
-                     (overlays-at (point)))))
+  (car (or (seq-filter (lambda (o) (overlay-get o 'beacon))
+                     (overlays-in (point) (point)))
+           (seq-filter (lambda (o) (overlay-get o 'beacon))
+                     (overlays-at (point))))))
 
 (defun beacon--vanish ()
   "Turn off the beacon."
@@ -110,12 +148,16 @@ Only returns `beacon-size' elements."
 
 (defun beacon--color-range ()
   "Return a list of background colors for the beacon."
-  (let ((bg (color-values (face-attribute 'default :background))))
-    (apply #'cl-mapcar (lambda (r g b) (format "#%04x%04x%04x" r g b))
-           (if (< (color-distance "black" bg)
+  (let* ((bg (color-values (face-attribute 'default :background)))
+         (fg (cond
+              ((stringp beacon-color) (color-values beacon-color))
+              ((< (color-distance "black" bg)
                   (color-distance "white" bg))
-               (mapcar (lambda (n) (butlast (beacon--int-range (* beacon-brightness 65535) n))) bg)
-             (mapcar (lambda (n) (cdr (beacon--int-range (* (- 1 beacon-brightness) 65535) n))) bg)))))
+               (make-list 3 (* beacon-color 65535)))
+              (t (make-list 3 (* (- 1 beacon-color) 65535))))))
+    (apply #'cl-mapcar (lambda (r g b) (format "#%04x%04x%04x" r g b))
+           (mapcar (lambda (n) (butlast (beacon--int-range (elt fg n) (elt bg n))))
+                   [0 1 2]))))
 
 
 ;;; Blinking
@@ -126,21 +168,29 @@ Only returns `beacon-size' elements."
       (while colors
         (if (looking-at "$")
             (progn
-              ;; (beacon--after-string)
+              (beacon--after-string-overlay colors)
               (setq colors nil))
           (beacon--colored-overlay (pop colors))
           (forward-char 1))))))
 
 (defun beacon--dec ()
   "Decrease the beacon brightness by one."
-  (let ((o (beacon--ov-at-point)))
-    (if (not o)
-        (beacon--vanish)
-      (delete-overlay o)
-      (save-excursion
-        (while (progn (forward-char 1)
-                      (setq o (beacon--ov-at-point)))
-          (move-overlay o (1- (point)) (point)))))))
+  (pcase (beacon--ov-at-point)
+    (`nil (beacon--vanish))
+    ((and o (let c (overlay-get o 'beacon-colors)) (guard c))
+     (beacon--ov-put-after-string o (cdr c)))
+    (o
+     (delete-overlay o)
+     (save-excursion
+       (while (progn (forward-char 1)
+                     (setq o (beacon--ov-at-point)))
+         (let ((colors (overlay-get o 'beacon-colors)))
+           (if (not colors)
+               (move-overlay o (1- (point)) (point))
+             (forward-char -1)
+             (beacon--colored-overlay (pop colors))
+             (beacon--ov-put-after-string o colors)
+             (forward-char 1))))))))
 
 (defun beacon-blink ()
   "Blink the beacon at the position of the cursor."
@@ -158,10 +208,23 @@ Only returns `beacon-size' elements."
 (defvar beacon--previous-window-start nil)
 (defvar beacon--previous-mark-head nil)
 
+(defun beacon--movement-> (delta)
+  "Return non-nil if latest point movement is > DELTA.
+If DELTA is nil, return nil."
+  (and delta
+       (markerp beacon--previous-place)
+       (equal (marker-buffer beacon--previous-place)
+              (current-buffer))
+       (> (abs (- (point) beacon--previous-place))
+          delta)
+       (> (count-screen-lines (min (point) beacon--previous-place)
+                              (max (point) beacon--previous-place))
+          delta)))
+
 (defun beacon--maybe-push-mark ()
   "Push mark if it seems to be safe."
-  (when (and beacon-push-mark
-             (not mark-active))
+  (when (and (not mark-active)
+             (beacon--movement-> beacon-push-mark))
     (let ((head (car mark-ring)))
       (when (and (eq beacon--previous-mark-head head)
                  (not (equal head beacon--previous-place)))
@@ -182,18 +245,13 @@ Only returns `beacon-size' elements."
    ((and beacon-blink-when-window-scrolls
          (progn (redisplay)
                 (not (equal beacon--previous-window-start (window-start)))))
-    (beacon--maybe-push-mark)
     (beacon-blink))
    ;; Blink for movement
-   ((and beacon-blink-when-point-moves
-         (> (abs (- (point) beacon--previous-place))
-            beacon-blink-when-point-moves)
-         (> (count-screen-lines (min (point) beacon--previous-place)
-                                (max (point) beacon--previous-place))))
-    (beacon--maybe-push-mark)
+   ((beacon--movement-> beacon-blink-when-point-moves)
     (beacon-blink))
    ;; Even if we don't blink, vanish any previous beacon.
    (t (beacon--vanish)))
+  (beacon--maybe-push-mark)
   (unless (window-minibuffer-p)
     (setq beacon--previous-window-start (window-start))
     (setq beacon--previous-mark-head (car mark-ring))
@@ -202,9 +260,9 @@ Only returns `beacon-size' elements."
 
 ;;; Minor-mode
 (defcustom beacon-lighter (cond
-                     ((char-displayable-p ?💡) "💡")
-                     ((char-displayable-p ?Λ) "Λ")
-                     (t "*"))
+                     ((char-displayable-p ?💡) " 💡")
+                     ((char-displayable-p ?Λ) " Λ")
+                     (t " *"))
   "Lighter string used on the mode-line."
   :type 'string)