* calendar/todos.el: Further comment revision and code

rearrangement.
(todos-item-end): Revert last change.
(todos-key-bindings, todos-menu, todos-archive-mode-map)
(todos-filter-items-mode-map): Use renamed commands.
(todos-hide-show-date-time): Rename from
todos-toggle-display-date-time.
(todos-mark-unmark-item): Rename from todos-toggle-mark-item and
adjust caller.
(todos-backward-item): Exempt special handling only from
todos-regexp-items-buffer instead of todos-filter-items-mode.
(todos-raise-item-priority): Don't allow item reprioritizing in
Todos filter items mode except for top priority items.

2 files changed, 139 insertions, 116 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 1675c86684d..6f41ead73ee 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,5 +1,21 @@
 2012-09-21  Stephen Berman  <stephen.berman@gmx.net>
 
+        * calendar/todos.el: Further comment revision and code
+        rearrangement.
+        (todos-item-end): Revert last change.
+        (todos-key-bindings, todos-menu, todos-archive-mode-map)
+        (todos-filter-items-mode-map): Use renamed commands.
+        (todos-hide-show-date-time): Rename from
+        todos-toggle-display-date-time.
+        (todos-mark-unmark-item): Rename from todos-toggle-mark-item and
+        adjust caller.
+        (todos-backward-item): Exempt special handling only from
+        todos-regexp-items-buffer instead of todos-filter-items-mode.
+        (todos-raise-item-priority): Don't allow item reprioritizing in
+        Todos filter items mode except for top priority items.
+
+2012-09-21  Stephen Berman  <stephen.berman@gmx.net>
+
         * calendar/todos.el: Add and revise further doc strings and
         comments.
         (todos-filter-function, todos-custom-items)
diff --git a/lisp/calendar/todos.el b/lisp/calendar/todos.el
index 88a19b60a57..266e87c47b5 100644
--- a/lisp/calendar/todos.el
+++ b/lisp/calendar/todos.el
@@ -779,6 +779,88 @@ categories display according to priority."
   :group 'todos-faces)
 (defvar todos-done-sep-face 'todos-done-sep)
 
+(defun todos-date-string-matcher (lim)
+  "Search for Todos date string within LIM for font-locking."
+  (re-search-forward
+   (concat todos-date-string-start "\\(?1:" todos-date-pattern "\\)") lim t))
+
+(defun todos-time-string-matcher (lim)
+  "Search for Todos time string within LIM for font-locking."
+  (re-search-forward (concat todos-date-string-start todos-date-pattern
+                             " \\(?1:" diary-time-regexp "\\)") lim t))
+
+(defun todos-nondiary-marker-matcher (lim)
+  "Search for Todos nondiary markers within LIM for font-locking."
+  (re-search-forward (concat "^\\(?1:" (regexp-quote todos-nondiary-start) "\\)"
+                             todos-date-pattern "\\(?: " diary-time-regexp
+                             "\\)?\\(?2:" (regexp-quote todos-nondiary-end) "\\)")
+                     lim t))
+
+(defun todos-diary-nonmarking-matcher (lim)
+  "Search for diary nonmarking symbol within LIM for font-locking."
+  (re-search-forward (concat "^\\(?1:" (regexp-quote diary-nonmarking-symbol)
+                             "\\)" todos-date-pattern) lim t))
+
+(defun todos-diary-expired-matcher (lim)
+  "Search for expired diary item date within LIM for font-locking."
+  (when (re-search-forward (concat "^\\(?:"
+                                   (regexp-quote diary-nonmarking-symbol)
+                                   "\\)?\\(?1:" todos-date-pattern "\\) \\(?2:"
+                                   diary-time-regexp "\\)?") lim t)
+    (let* ((date (match-string-no-properties 1))
+           (time (match-string-no-properties 2))
+           ;; days-between needs a non-empty time string.
+           (date-time (concat date " " (or time "00:00"))))
+      (or (and (not (string-match ".+day\\|\\*" date))
+               (< (days-between date-time (current-time-string)) 0))
+          (todos-diary-expired-matcher lim)))))
+
+(defun todos-done-string-matcher (lim)
+  "Search for Todos done header within LIM for font-locking."
+  (re-search-forward (concat todos-done-string-start
+                      "[^][]+]")
+                     lim t))
+
+(defun todos-comment-string-matcher (lim)
+  "Search for Todos done comment within LIM for font-locking."
+  (re-search-forward (concat "\\[\\(?1:" todos-comment-string "\\):")
+                     lim t))
+
+;; (defun todos-category-string-matcher (lim)
+;;   "Search for Todos category name within LIM for font-locking.
+;; This is for fontifying category names appearing in Todos filter
+;; mode."
+;;   (if (eq major-mode 'todos-filter-items-mode)
+;;       (re-search-forward
+;;        (concat "^\\(?:" todos-date-string-start "\\)?" todos-date-pattern
+;;                     "\\(?: " diary-time-regexp "\\)?\\(?:"
+;;                     (regexp-quote todos-nondiary-end) "\\)? \\(?1:\\[.+\\]\\)")
+;;        lim t)))
+
+(defun todos-category-string-matcher-1 (lim)
+  "Search for Todos category name within LIM for font-locking.
+This is for fontifying category names appearing in Todos filter
+mode following done items."
+  (if (eq major-mode 'todos-filter-items-mode)
+      (re-search-forward (concat todos-done-string-start todos-date-pattern
+                                 "\\(?: " diary-time-regexp
+                                 ;; Use non-greedy operator to prevent
+                                 ;; capturing possible following non-diary
+                                 ;; date string.
+                                 "\\)?] \\(?1:\\[.+?\\]\\)")
+                         lim t)))
+
+(defun todos-category-string-matcher-2 (lim)
+  "Search for Todos category name within LIM for font-locking.
+This is for fontifying category names appearing in Todos filter
+mode following todo (not done) items."
+  (if (eq major-mode 'todos-filter-items-mode)
+      (re-search-forward (concat todos-date-string-start todos-date-pattern
+                                 "\\(?: " diary-time-regexp "\\)?\\(?:"
+                                 (regexp-quote todos-nondiary-end)
+                                 "\\)? \\(?1:\\[.+\\]\\)")
+                         lim t)))
+
 (defvar todos-font-lock-keywords
   (list
    '(todos-nondiary-marker-matcher 1 todos-done-sep-face t)
@@ -933,88 +1015,6 @@ users option `todos-show-current-file' is non-nil).")
   (concat "^\\[" (regexp-quote todos-done-string))
   "Regular expression matching start of done item.")
 
-(defun todos-date-string-matcher (lim)
-  "Search for Todos date string within LIM for font-locking."
-  (re-search-forward
-   (concat todos-date-string-start "\\(?1:" todos-date-pattern "\\)") lim t))
-
-(defun todos-time-string-matcher (lim)
-  "Search for Todos time string within LIM for font-locking."
-  (re-search-forward (concat todos-date-string-start todos-date-pattern
-                             " \\(?1:" diary-time-regexp "\\)") lim t))
-
-(defun todos-nondiary-marker-matcher (lim)
-  "Search for Todos nondiary markers within LIM for font-locking."
-  (re-search-forward (concat "^\\(?1:" (regexp-quote todos-nondiary-start) "\\)"
-                             todos-date-pattern "\\(?: " diary-time-regexp
-                             "\\)?\\(?2:" (regexp-quote todos-nondiary-end) "\\)")
-                     lim t))
-
-(defun todos-diary-nonmarking-matcher (lim)
-  "Search for diary nonmarking symbol within LIM for font-locking."
-  (re-search-forward (concat "^\\(?1:" (regexp-quote diary-nonmarking-symbol)
-                             "\\)" todos-date-pattern) lim t))
-
-(defun todos-diary-expired-matcher (lim)
-  "Search for expired diary item date within LIM for font-locking."
-  (when (re-search-forward (concat "^\\(?:"
-                                   (regexp-quote diary-nonmarking-symbol)
-                                   "\\)?\\(?1:" todos-date-pattern "\\) \\(?2:"
-                                   diary-time-regexp "\\)?") lim t)
-    (let* ((date (match-string-no-properties 1))
-           (time (match-string-no-properties 2))
-           ;; days-between needs a non-empty time string.
-           (date-time (concat date " " (or time "00:00"))))
-      (or (and (not (string-match ".+day\\|\\*" date))
-               (< (days-between date-time (current-time-string)) 0))
-          (todos-diary-expired-matcher lim)))))
-
-(defun todos-done-string-matcher (lim)
-  "Search for Todos done header within LIM for font-locking."
-  (re-search-forward (concat todos-done-string-start
-                      "[^][]+]")
-                     lim t))
-
-(defun todos-comment-string-matcher (lim)
-  "Search for Todos done comment within LIM for font-locking."
-  (re-search-forward (concat "\\[\\(?1:" todos-comment-string "\\):")
-                     lim t))
-
-;; (defun todos-category-string-matcher (lim)
-;;   "Search for Todos category name within LIM for font-locking.
-;; This is for fontifying category names appearing in Todos filter
-;; mode."
-;;   (if (eq major-mode 'todos-filter-items-mode)
-;;       (re-search-forward
-;;        (concat "^\\(?:" todos-date-string-start "\\)?" todos-date-pattern
-;;                     "\\(?: " diary-time-regexp "\\)?\\(?:"
-;;                     (regexp-quote todos-nondiary-end) "\\)? \\(?1:\\[.+\\]\\)")
-;;        lim t)))
-
-(defun todos-category-string-matcher-1 (lim)
-  "Search for Todos category name within LIM for font-locking.
-This is for fontifying category names appearing in Todos filter
-mode following done items."
-  (if (eq major-mode 'todos-filter-items-mode)
-      (re-search-forward (concat todos-done-string-start todos-date-pattern
-                                 "\\(?: " diary-time-regexp
-                                 ;; Use non-greedy operator to prevent
-                                 ;; capturing possible following non-diary
-                                 ;; date string.
-                                 "\\)?] \\(?1:\\[.+?\\]\\)")
-                         lim t)))
-
-(defun todos-category-string-matcher-2 (lim)
-  "Search for Todos category name within LIM for font-locking.
-This is for fontifying category names appearing in Todos filter
-mode following todo (not done) items."
-  (if (eq major-mode 'todos-filter-items-mode)
-      (re-search-forward (concat todos-date-string-start todos-date-pattern
-                                 "\\(?: " diary-time-regexp "\\)?\\(?:"
-                                 (regexp-quote todos-nondiary-end)
-                                 "\\)? \\(?1:\\[.+\\]\\)")
-                         lim t)))
-
 (defun todos-category-number (cat)
   "Return the number of category CAT in this Todos file.
 The buffer-local variable `todos-category-number' holds this
@@ -1282,11 +1282,10 @@ editing or a bug in todos.el."
   (unless (looking-at "^$")
     (let ((done (todos-done-item-p)))
       (todos-forward-item)
-      (unless (eq major-mode 'todos-filter-items-mode)
-        ;; Adjust if item is last unfinished one before displayed done items.
-        (when (and (not done) (todos-done-item-p))
-          (forward-line -1))
-        (backward-char)))
+      ;; Adjust if item is last unfinished one before displayed done items.
+      (when (and (not done) (todos-done-item-p))
+        (forward-line -1))
+      (backward-char))
     (point)))
 
 (defun todos-item-string ()
@@ -2238,8 +2237,8 @@ which is the value of the user option
     ;(""             . todos-display-categories-alphabetically)
     ("H"             . todos-highlight-item)
     ("N"             . todos-toggle-item-numbering)
-    ("D"             . todos-toggle-display-date-time)
-    ("*"             . todos-toggle-mark-item)
+    ("D"             . todos-hide-show-date-time)
+    ("*"             . todos-mark-unmark-item)
     ("C*"            . todos-mark-category)
     ("Cu"            . todos-unmark-category)
     ("PP"            . todos-print)
@@ -2254,7 +2253,7 @@ which is the value of the user option
     ("Fe"            . todos-edit-multiline)
     ("Fh"            . todos-highlight-item)
     ("Fn"            . todos-toggle-item-numbering)
-    ("Fd"            . todos-toggle-display-date-time)
+    ("Fd"            . todos-hide-show-date-time)
     ("Ftt"           . todos-top-priorities)
     ("Ftm"           . todos-top-priorities-multifile)
     ("Fts"           . todos-set-top-priorities-in-file)
@@ -2345,7 +2344,7 @@ which is the value of the user option
      ;; ["List Categories Alphabetically" todos-display-categories-alphabetically t]
      ["Turn Item Highlighting on/off" todos-highlight-item t]
      ["Turn Item Numbering on/off" todos-toggle-item-numbering t]
-     ["Turn Item Time Stamp on/off" todos-toggle-display-date-time t]
+     ["Turn Item Time Stamp on/off" todos-hide-show-date-time t]
      ["View/Hide Done Items" todos-toggle-view-done-items t]
      "---"
      ["View Diary Items" todos-diary-items t]
@@ -2399,7 +2398,7 @@ which is the value of the user option
     (define-key map "C" 'todos-display-categories)
     (define-key map "H" 'todos-highlight-item)
     (define-key map "N" 'todos-toggle-item-numbering)
-    ;; (define-key map "" 'todos-toggle-display-date-time)
+    ;; (define-key map "" 'todos-hide-show-date-time)
     (define-key map "P" 'todos-print)
     (define-key map "q" 'todos-quit)
     (define-key map "s" 'todos-save)
@@ -2447,7 +2446,7 @@ which is the value of the user option
     (define-key map "p" 'todos-backward-item)
     (define-key map "H" 'todos-highlight-item)
     (define-key map "N" 'todos-toggle-item-numbering)
-    (define-key map "D" 'todos-toggle-display-date-time)
+    (define-key map "D" 'todos-hide-show-date-time)
     (define-key map "P" 'todos-print)
     (define-key map "q" 'todos-quit)
     (define-key map "s" 'todos-save)
@@ -2637,6 +2636,10 @@ and done items are always shown on visiting a category."
                      (concat (file-name-sans-extension todos-current-todos-file)
                              ".todo"))
                     (t
+                     ;; FIXME: If an archive is value of
+                     ;; todos-current-todos-file, todos-show will revisit
+                     ;; rather than the corresponding todo file -- ok or make
+                     ;; it customizable?
                      (or todos-current-todos-file
                          (and todos-show-current-file
                               todos-global-current-todos-file)
@@ -2775,7 +2778,7 @@ last category displayed."
       (hl-line-mode -1)
     (hl-line-mode 1)))
 
-(defun todos-toggle-display-date-time () ;(&optional all)
+(defun todos-hide-show-date-time () ;(&optional all)
   "Hide or show date-time header of todo items.";; in current category.
 ;; With non-nil prefix argument ALL do this in the whole file."
   (interactive "P")
@@ -2804,7 +2807,7 @@ last category displayed."
                 (overlay-put ov 'display "")))
             (todos-forward-item)))))))
 
-(defun todos-toggle-mark-item (&optional n all)
+(defun todos-mark-unmark-item (&optional n all)
   "Mark item at point if unmarked, or unmark it if marked.
 
 With a positive numerical prefix argument N, change the
@@ -2845,7 +2848,7 @@ is \"*\", then the mark is \"@\"."
   "Put the \"*\" mark on all items in this category.
 \(If `todos-prefix' is \"*\", then the mark is \"@\".)"
   (interactive)
-  (todos-toggle-mark-item 0 t))
+  (todos-mark-unmark-item 0 t))
 
 (defun todos-unmark-category ()
   "Remove the \"*\" mark from all items in this category.
@@ -3292,15 +3295,15 @@ With numerical prefix COUNT, move point COUNT items upward,"
     (todos-item-start)
     (unless (bobp)
       (re-search-backward todos-item-start nil t (or count 1)))
-    (unless (eq major-mode 'todos-filter-items-mode)
-      ;; If points advances by one from a done to a todo item, go back to the
-      ;; space above todos-done-separator, since that is a legitimate place to
-      ;; insert an item.  But skip this space if count > 1, since that should
-      ;; only stop on an item (FIXME: or not?)
-      (when (and done (not (todos-done-item-p))
-                 (or (not count) (= count 1)))
-        (re-search-forward (concat "^" (regexp-quote todos-category-done)) nil t)
-        (forward-line -1)))))
+    ;; Unless this is a regexp filtered items buffer (which can contain
+    ;; intermixed todo and done items), if points advances by one from a done
+    ;; to a todo item, go back to the space above todos-done-separator, since
+    ;; that is a legitimate place to insert an item.  But skip this space if
+    ;; count > 1, since that should only stop on an item (FIXME: or not?)
+    (when (and done (not (todos-done-item-p)) (or (not count) (= count 1))
+               (not (equal (buffer-name) todos-regexp-items-buffer)))
+      (re-search-forward (concat "^" (regexp-quote todos-category-done)) nil t)
+      (forward-line -1))))
 
 ;; FIXME: (i) Extend search to other Todos files. (ii) Allow navigating among
 ;; hits.
@@ -3823,16 +3826,16 @@ the new item:
 
 To facilitate using these arguments when inserting a new todo
 item, convenience commands have been defined for all admissible
-combinations (96 in all!) together with mnenomic key bindings
-based on on the name of the arguments and their order in the
-command's argument list: diar_y_ - nonmar_k_ing - _c_alendar or
-_d_ate or day_n_ame - _t_ime - _r_egion or _h_ere.  These key
-combinations are appended to the basic insertion key (i) and keys
-that allow a following key must be doubled when used finally.
-For example, `iyh' will insert a new item with today's date,
-marked according to the DIARY argument described above, and with
-priority according to the HERE argument; while `iyy' does the
-same except the priority is not given by HERE but by prompting."
+combinations together with mnenomic key bindings based on on the
+name of the arguments and their order in the command's argument
+list: diar_y_ - nonmar_k_ing - _c_alendar or _d_ate or day_n_ame
+- _t_ime - _r_egion or _h_ere.  These key combinations are
+appended to the basic insertion key (i) and keys that allow a
+following key must be doubled when used finally.  For example,
+`iyh' will insert a new item with today's date, marked according
+to the DIARY argument described above, and with priority
+according to the HERE argument; while `iyy' does the same except
+the priority is not given by HERE but by prompting."
 ;;   An alternative interface for customizing key
 ;; binding is also provided with the function
 ;; `todos-insertion-bindings'."         ;FIXME
@@ -4269,6 +4272,10 @@ items in this category."
 With non-nil argument LOWER lower item's priority."
   (interactive)
   (unless (or (todos-done-item-p)
+              (and (eq major-mode 'todos-filter-items-mode)
+                   ;; Items in Top Priorities buffer can be reprioritized.
+                   (not (string-match (regexp-quote todos-top-priorities-buffer)
+                                      (buffer-name))))
               ;; Point is between todo and done items.
               (looking-at "^$"))
     (let (buffer-read-only)
@@ -4282,7 +4289,7 @@ With non-nil argument LOWER lower item's priority."
               (> (count-lines (point-min) (point)) 0))
           (let ((item (todos-item-string))
                 (marked (todos-marked-item-p)))
-            ;; In Todos Top Priorities mode, an item's priority can be changed
+            ;; In Top Priorities buffer, an item's priority can be changed
             ;; wrt items in another category, but not wrt items in the same
             ;; category.
             (when (eq major-mode 'todos-filter-items-mode)