mu4e-bookmarks: show favorite bookmark info

mu4e/mu4e-bookmarks.el

@@ -1,6 +1,6 @@
 ;;; mu4e-bookmarks.el -- part of mu4e -*- lexical-binding: t -*-
 
-;; Copyright (C) 2011-2022 Dirk-Jan C. Binnema
+;; Copyright (C) 2011-2023 Dirk-Jan C. Binnema
 
 ;; Author: Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
 ;; Maintainer: Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
@@ -24,6 +24,8 @@
 
 ;;; Code:
 (require 'mu4e-helpers)
+(require 'mu4e-server)
+(require 'mu4e-modeline)
 
 
 ;;; Configuration
@@ -50,19 +52,24 @@
 
 Each of the list elements is a plist with at least:
 `:name'  - the name of the query
-`:query' - the query expression or function
+`:query' - the query expression string (not a function)
-`:key'   - the shortcut key.
+`:key'   - the shortcut key (single character)
 
 Note that the :query parameter can be a function/lambda.
 
-Optionally, you can add the following: `:hide' - if t, the
+Optionally, you can add the following:
-bookmark is hidden from the main-view and speedbar.
-`:hide-unread' - do not show the counts of unread/total number of
-matches for the query in the main-view. This can be useful if a
-bookmark uses a very slow query.
 
-`:hide-unread' is implied from `:hide'. Furthermore, it is
+- `:favorite' - if t, monitor the results of this query, and make
-implied when `:query' is a function.
+it eligible for showing its status in the emacs modeline. At mose
+one bookmark should have this set to t (otherwise the _first_
+bookmark is the implicit favorite)
+- `:hide' - if t, the bookmark is hidden from the main-view and
+speedbar.
+- `:hide-unread' - do not show the counts of
+unread/total number of matches for the query in the main-view.
+This can be useful if a bookmark uses a very slow query.
+
+`:hide-unread' is implied from `:hide'.
 
 Note: for efficiency, queries used to determine the unread/all
 counts do not discard duplicate or unreadable messages. Thus, the
@@ -88,23 +95,32 @@ query."
          (kar (read-char (concat prompt bmarks))))
     (mu4e-get-bookmark-query kar)))
 
+
+(defun mu4e--bookmark-query (bm)
+  "Get query string for some bookmark."
+  (when bm
+    (let* ((query (or (plist-get bm :query)
+                      (mu4e-warn "No query in %S" bm)))
+           ;; queries being functions is deprecated.
+           (query (if (functionp query) (funcall query) query)))
+      ;; earlier, we allowed for the queries being fucntions
+      (unless (stringp query)
+        (mu4e-warn "Could not get query string from %s" bm))
+      ;; apparently, non-UTF8 queries exist, i.e.,
+      ;; with maild dir names.
+      (decode-coding-string query 'utf-8 t))))
+
+
 (defun mu4e-get-bookmark-query (kar)
   "Get the corresponding bookmarked query for shortcut KAR.
 Raise an error if none is found."
-  (let* ((chosen-bm
+  (let ((chosen-bm
          (or (seq-find
               (lambda (bm)
                 (= kar (plist-get bm :key)))
               (mu4e-bookmarks))
-              (mu4e-warn "Unknown shortcut '%c'" kar)))
+             (mu4e-warn "Unknown shortcut '%c'" kar))))
-         (expr (plist-get chosen-bm :query))
+    (mu4e--bookmark-query chosen-bm)))
-         (expr (if (not (functionp expr)) expr
-                 (funcall expr)))
-         (query (eval expr)))
-    (if (stringp query)
-        query
-      (mu4e-warn "Expression must evaluate to query string ('%S')" expr))))
-
 
 (defun mu4e-bookmark-define (query name key)
   "Define a bookmark for QUERY with NAME and shortcut KEY.
@@ -127,7 +143,157 @@ Convert from the old format if needed."
              (if (and (listp item) (= (length item) 3))
                `(:name  ,(nth 1 item) :query ,(nth 0 item)
                         :key   ,(nth 2 item))
-               item)) mu4e-bookmarks))
+               item))
+           mu4e-bookmarks))
+
+(defun mu4e-favorite-bookmark ()
+  "Find the favorite bookmark.
+The favorit bookmark is the first one that has a non-nil
+':favorite' property, or the first if there is none."
+  (let ((bookmarks (mu4e-bookmarks)))
+    (or (seq-find (lambda (bm) (plist-get bm :favorite))
+                  (mu4e-bookmarks))
+        (car-safe bookmarks))))
+
+;;; Last & baseline query results for bookmarks.
+
+(defvar mu4e--baseline nil
+  "Some previous version of the query-results.
+This is used as the baseline to track updates by comparing it to
+the latest query-results.")
+(defvar mu4e--baseline-tstamp nil
+  "Timestamp for when the query-results baseline was updated.")
+
+(defun mu4e--reset-baseline ()
+  (setq mu4e--baseline (mu4e-server-query-results)
+        mu4e--baseline-tstamp (current-time))
+  (mu4e-last-query-results 'force)) ; for side-effects
+
+
+(defvar mu4e--last-query-results-cached nil)
+(defun mu4e-last-query-results(&optional force)
+  "Get the results (counts) of the latest queries.
+
+Either read form the cache or update them when oudated or FORCE
+is non-nil.
+
+The queries are the bookmark / maildir queries that are used to
+populate the read/unread counts in the main view and modeline.
+They are refreshed when calling `(mu4e)', i.e., when going to the
+main view.
+
+When available, the baseline results are added as well.
+
+The results are a list of elements of the form
+   (:query \"query string\"
+      :count  <total number matching count>
+      :unread <number of unread messages in count>
+      [:favorite t]
+      :baseline ( ;; baseline results
+         :count  <total number matching count>
+         :unread <number of unread messages in count>)) The
+baseline part is optional (see `mu4e-reset-query-results') for
+more details).
+
+Uses a cached string unless its nil or FORCE is non-nil."
+  (if (and mu4e--last-query-results-cached (not force))
+      mu4e--last-query-results-cached ;; use cache
+    ;; otherwise, recalculate.
+    (let* ((favorite (mu4e-favorite-bookmark))
+           (favorite-query
+            (and favorite (mu4e--bookmark-query favorite))))
+      (setq mu4e--last-query-results-cached ;; walk over the remembered queries
+            ;; and augment them with the baseline data and ':favorite' flag, if
+            ;; any.
+            (seq-map
+             (lambda (qres)
+               ;; note: queries can be _functions_ too; use their
+               ;; string value.
+               (let* ((query (mu4e--bookmark-query qres))
+                      (bres (seq-find ;; find the corresponding baseline entry
+                             (lambda (bq)
+                               (string= query (mu4e--bookmark-query bq)))
+                             mu4e--baseline)))
+                 (when (string= query (or favorite-query ""))
+                   (plist-put qres :favorite t))
+                 (when bres
+                   (plist-put qres :baseline
+                              `(:count ,(plist-get bres :count)
+                                :unread ,(plist-get bres :unread))))
+                 qres)) (mu4e-server-query-results))))))
+
+(defun mu4e-last-query-result (query)
+  "Get the last result for some QUERY or nil if not found.
+See `mu4e-last-query-results' for the format."
+  (seq-find
+   (lambda (elm) (string= query (mu4e--bookmark-query elm)))
+   (mu4e-last-query-results)))
+
+;; for Zero-Inbox afficionados
+(defvar mu4e-modeline-all-clear                   '("C:" . "🌀")
+  "No more messages at all for this query.")
+(defvar mu4e-modeline-all-read                    '("R:" . "✅")
+  "No unread messages left.")
+(defvar mu4e-modeline-unread-items                '("U:" . "📫")
+  "There are some unread items.")
+(defvar mu4e-modeline-new-items                   '("N:" . "🔥")
+  "There are some new items after the baseline.
+I.e., very new messages.")
+
+(declare-function mu4e-search-bookmark "mu4e-search")
+(defun mu4e-jump-to-favorite ()
+  "Jump to to the favorite bookmark, if any."
+  (interactive)
+  (when-let ((fav (mu4e--bookmark-query (mu4e-favorite-bookmark))))
+    (mu4e-search-bookmark fav)))
+
+(defvar mu4e--bookmarks-modeline-cached nil)
+
+(defun mu4e--bookmarks-modeline-item ()
+  "Modeline item showing message counts for the favorite bookmark.
+
+This uses the one special ':favorite' bookmark, and if there is
+one, creates a propertized string for display in the modeline."
+  (or mu4e--bookmarks-modeline-cached
+      (setq mu4e--bookmarks-modeline-cached
+            (when-let ((fav ;; any results for the favorite bookmark item?
+                        (seq-find (lambda (bm) (plist-get bm :favorite))
+                                  (mu4e-last-query-results))))
+              (let* ((unread (plist-get   fav :unread))
+                     (count  (plist-get   fav :count))
+                     (baseline (plist-get fav :baseline))
+                     (baseline-unread
+                      (or (when baseline (plist-get baseline :unread)) unread))
+                     (delta (- unread baseline-unread)))
+                (propertize
+                 (format "%s%s%s/%s "
+                         (funcall (if mu4e-use-fancy-chars 'cdr 'car)
+                                  (cond
+                                   ((> delta 0)  mu4e-modeline-new-items)
+                                   ((> unread 0) mu4e-modeline-unread-items)
+                                   ((> count 0) mu4e-modeline-all-read)
+                                   (t mu4e-modeline-all-clear)))
+                         (propertize (number-to-string unread) 'face 'mu4e-header-key-face)
+                         (if (<= delta 0) ""
+                           (propertize (format "(%+d)" delta)
+                                       'face 'mu4e-unread-face))
+                         (number-to-string count))
+                 'help-echo (format "mu4e query: '%s'" (mu4e--bookmark-query fav))
+                 'mouse-face 'mode-line-highlight
+                 'keymap '(mode-line keymap
+                                     (mouse-1   . mu4e-jump-to-favorite)
+                                     (mouse-2   . mu4e-jump-to-favorite)
+                                     (mouse-3   . mu4e-jump-to-favorite))))))))
+
+
+(defun mu4e--modeline-update()
+  "Update the modeline and redisplay if mu4e-modeline-mode is
+active."
+  (when mu4e-modeline-mode
+    (setq mu4e--bookmarks-modeline-cached nil) ;; force recalculation
+    (force-mode-line-update)))
+
+
 
 (provide 'mu4e-bookmarks)
 ;;; mu4e-bookmarks.el ends here