From 364beec6d1470712415a36f5810e4f7d320c6b0f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Peter=20M=C3=BCnster?= <pm@a16n.net>
Date: Wed, 18 Aug 2021 11:21:51 +0200
Subject: [PATCH 6/6] Add support for history of image tags and completion in
 the minibuffer

* lisp/image-dired.el (image-dired-tag-history): New variable holding the
tag history.
(image-dired-tag-files, image-dired-tag-thumbnail, image-dired-delete-tag)
(image-dired-tag-thumbnail-remove): Use it for the user input.
---
 lisp/image-dired.el | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/lisp/image-dired.el b/lisp/image-dired.el
index 5ee66b0e90..5a332964d5 100644
--- a/lisp/image-dired.el
+++ b/lisp/image-dired.el
@@ -652,6 +652,8 @@ image-dired-queue-active-limit
   "Maximum number of concurrent jobs permitted for generating images.
 Increase at own risk.")
 
+(defvar image-dired-tag-history nil "Variable holding the tag history.")
+
 (defun image-dired-pngnq-thumb (spec)
   "Quantize thumbnail described by format SPEC with pngnq(1)."
   (let ((process
@@ -1146,7 +1148,9 @@ image-dired-list-tags
 (defun image-dired-tag-files (arg)
   "Tag marked file(s) in dired.  With prefix ARG, tag file at point."
   (interactive "P")
-  (let ((tag (read-string "Tags to add (separate tags with a semicolon): "))
+  (let ((tag (completing-read
+              "Tags to add (separate tags with a semicolon): "
+              image-dired-tag-history nil nil nil 'image-dired-tag-history))
         files)
     (if arg
         (setq files (list (dired-get-filename)))
@@ -1160,7 +1164,9 @@ image-dired-tag-files
 (defun image-dired-tag-thumbnail ()
   "Tag current or marked thumbnails."
   (interactive)
-  (let ((tag (read-string "Tags to add (separate tags with a semicolon): ")))
+  (let ((tag (completing-read
+              "Tags to add (separate tags with a semicolon): "
+              image-dired-tag-history nil nil nil 'image-dired-tag-history)))
     (image-dired--with-marked
      (image-dired-write-tags
       (list (cons (image-dired-original-file-name) tag)))
@@ -1172,7 +1178,8 @@ image-dired-delete-tag
   "Remove tag for selected file(s).
 With prefix argument ARG, remove tag from file at point."
   (interactive "P")
-  (let ((tag (read-string "Tag to remove: "))
+  (let ((tag (completing-read "Tag to remove: " image-dired-tag-history
+                              nil nil nil 'image-dired-tag-history))
         files)
     (if arg
         (setq files (list (dired-get-filename)))
@@ -1182,7 +1189,8 @@ image-dired-delete-tag
 (defun image-dired-tag-thumbnail-remove ()
   "Remove tag from current or marked thumbnails."
   (interactive)
-  (let ((tag (read-string "Tag to remove: ")))
+  (let ((tag (completing-read "Tag to remove: " image-dired-tag-history
+                              nil nil nil 'image-dired-tag-history)))
     (image-dired--with-marked
      (image-dired-remove-tag (image-dired-original-file-name) tag)
      (image-dired-update-property
-- 
2.26.2