X-Git-Url: http://cgit.sxemacs.org/?a=blobdiff_plain;f=lisp%2Fgnus-topic.el;h=cf4f601e599ab53e3bae67b16a92a4f6438d9d3c;hb=6565967e150bf77c301b9a10dc5d3db3fa7dc385;hp=f30c26c0650e7f39f1605b12902d21a06e984860;hpb=44a2a6a79d7681974e94c543c591f6ff8fdda799;p=gnus

diff --git a/lisp/gnus-topic.el b/lisp/gnus-topic.el
index f30c26c06..cf4f601e5 100644
--- a/lisp/gnus-topic.el
+++ b/lisp/gnus-topic.el
@@ -27,7 +27,8 @@
 ;;; Code:
 
 (require 'gnus)
-(eval-when-compile (require 'cl))
+(require 'gnus-group)
+(require 'gnus-start)
 
 (defvar gnus-topic-mode nil
   "Minor mode for Gnus group buffers.")
@@ -48,17 +49,20 @@ with some simple extensions.
 %A  Number of unread articles in the groups in the topic and its subtopics.
 ")
 
-(defvar gnus-topic-unique t
-  "*If non-nil, each group will only belong to one topic.")
-
 (defvar gnus-topic-indent-level 2
   "*How much each subtopic should be indented.")
 
+(defvar gnus-topic-display-empty-topics t
+  "*If non-nil, display the topic lines even of topics that have no unread articles.")
+
 ;; Internal variables.
 
 (defvar gnus-topic-active-topology nil)
 (defvar gnus-topic-active-alist nil)
 
+(defvar gnus-topology-checked-p nil
+  "Whether the topology has been checked in this session.")
+
 (defvar gnus-topic-killed-topics nil)
 (defvar gnus-topic-inhibit-change-level nil)
 (defvar gnus-topic-tallied-groups nil)
@@ -74,7 +78,7 @@ with some simple extensions.
 
 (defvar gnus-topic-line-format-spec nil)
 
-;; Functions.
+;;; Utility functions
 
 (defun gnus-group-topic-name ()
   "The name of the topic on the current line."
@@ -89,19 +93,237 @@ with some simple extensions.
   "The number of unread articles in topic on the current line."
   (get-text-property (gnus-point-at-bol) 'gnus-topic-unread))
 
-(defun gnus-topic-init-alist ()
-  "Initialize the topic structures."
-  (setq gnus-topic-topology
-	(cons (list "Gnus" 'visible)
-	      (mapcar (lambda (topic)
-			(list (list (car topic) 'visible)))
-		      '(("misc")))))
-  (setq gnus-topic-alist
-	(list (cons "misc"
-		    (mapcar (lambda (info) (gnus-info-group info))
-			    (cdr gnus-newsrc-alist)))
-	      (list "Gnus")))
-  (gnus-topic-enter-dribble))
+(defun gnus-topic-unread (topic)
+  "Return the number of unread articles in TOPIC."
+  (or (save-excursion
+	(and (gnus-topic-goto-topic topic)
+	     (gnus-group-topic-unread)))
+      0))
+
+(defun gnus-group-topic-p ()
+  "Return non-nil if the current line is a topic."
+  (gnus-group-topic-name))
+
+(defun gnus-topic-visible-p ()
+  "Return non-nil if the current topic is visible."
+  (get-text-property (gnus-point-at-bol) 'gnus-topic-visible))
+
+(defun gnus-topic-articles-in-topic (entries)
+  (let ((total 0)
+	number)
+    (while entries
+      (when (numberp (setq number (car (pop entries))))
+	(incf total number)))
+    total))
+
+(defun gnus-group-topic (group)
+  "Return the topic GROUP is a member of."
+  (let ((alist gnus-topic-alist)
+	out)
+    (while alist
+      (when (member group (cdar alist))
+	(setq out (caar alist)
+	      alist nil))
+      (setq alist (cdr alist)))
+    out))
+
+(defun gnus-group-parent-topic (group)
+  "Return the topic GROUP is member of by looking at the group buffer."
+  (save-excursion
+    (set-buffer gnus-group-buffer)
+    (if (gnus-group-goto-group group)
+	(gnus-current-topic)
+      (gnus-group-topic group))))
+
+(defun gnus-topic-goto-topic (topic)
+  "Go to TOPIC."
+  (when topic
+    (gnus-goto-char (text-property-any (point-min) (point-max)
+				       'gnus-topic (intern topic)))))
+
+(defun gnus-current-topic ()
+  "Return the name of the current topic."
+  (let ((result
+	 (or (get-text-property (point) 'gnus-topic)
+	     (save-excursion
+	       (and (gnus-goto-char (previous-single-property-change
+				     (point) 'gnus-topic))
+		    (get-text-property (max (1- (point)) (point-min))
+				       'gnus-topic))))))
+    (when result
+      (symbol-name result))))
+
+(defun gnus-current-topics ()
+  "Return a list of all current topics, lowest in hierarchy first."
+  (let ((topic (gnus-current-topic))
+	topics)
+    (while topic
+      (push topic topics)
+      (setq topic (gnus-topic-parent-topic topic)))
+    (nreverse topics)))
+
+(defun gnus-group-active-topic-p ()
+  "Say whether the current topic comes from the active topics."
+  (save-excursion
+    (beginning-of-line)
+    (get-text-property (point) 'gnus-active)))
+
+(defun gnus-topic-find-groups (topic &optional level all)
+  "Return entries for all visible groups in TOPIC."
+  (let ((groups (cdr (assoc topic gnus-topic-alist)))
+        info clevel unread group lowest params visible-groups entry active)
+    (setq lowest (or lowest 1))
+    (setq level (or level 7))
+    ;; We go through the newsrc to look for matches.
+    (while groups
+      (setq entry (gnus-gethash (setq group (pop groups)) gnus-newsrc-hashtb)
+	    info (nth 2 entry)
+	    params (gnus-info-params info)
+	    active (gnus-active group)
+            unread (or (car entry)
+		       (and (not (equal group "dummy.group"))
+			    active
+			    (- (1+ (cdr active)) (car active))))
+	    clevel (or (gnus-info-level info)
+		       (if (member group gnus-zombie-list) 8 9)))
+      (and 
+       unread				; nil means that the group is dead.
+       (<= clevel level)
+       (>= clevel lowest)		; Is inside the level we want.
+       (or all
+	   (if (eq unread t)
+	       gnus-group-list-inactive-groups
+	     (> unread 0))
+	   (and gnus-list-groups-with-ticked-articles
+		(cdr (assq 'tick (gnus-info-marks info))))
+					; Has right readedness.
+	   ;; Check for permanent visibility.
+	   (and gnus-permanently-visible-groups
+		(string-match gnus-permanently-visible-groups group))
+	   (memq 'visible params)
+	   (cdr (assq 'visible params)))
+       ;; Add this group to the list of visible groups.
+       (push (or entry group) visible-groups)))
+    (nreverse visible-groups)))
+
+(defun gnus-topic-previous-topic (topic)
+  "Return the previous topic on the same level as TOPIC."
+  (let ((top (cddr (gnus-topic-find-topology
+		    (gnus-topic-parent-topic topic)))))
+    (unless (equal topic (caaar top))
+      (while (and top (not (equal (caaadr top) topic)))
+	(setq top (cdr top)))
+      (caaar top))))
+
+(defun gnus-topic-parent-topic (topic &optional topology)
+  "Return the parent of TOPIC."
+  (unless topology
+    (setq topology gnus-topic-topology))
+  (let ((parent (car (pop topology)))
+	result found)
+    (while (and topology
+		(not (setq found (equal (caaar topology) topic)))
+		(not (setq result (gnus-topic-parent-topic topic 
+							   (car topology)))))
+      (setq topology (cdr topology)))
+    (or result (and found parent))))
+
+(defun gnus-topic-next-topic (topic &optional previous)
+  "Return the next sibling of TOPIC."
+  (let ((parentt (cddr (gnus-topic-find-topology 
+			(gnus-topic-parent-topic topic))))
+	prev)
+    (while (and parentt
+		(not (equal (caaar parentt) topic)))
+      (setq prev (caaar parentt)
+	    parentt (cdr parentt)))
+    (if previous
+	prev
+      (caaadr parentt))))
+
+(defun gnus-topic-find-topology (topic &optional topology level remove)
+  "Return the topology of TOPIC."
+  (unless topology
+    (setq topology gnus-topic-topology)
+    (setq level 0))
+  (let ((top topology)
+	result)
+    (if (equal (caar topology) topic)
+	(progn
+	  (when remove
+	    (delq topology remove))
+	  (cons level topology))
+      (setq topology (cdr topology))
+      (while (and topology
+		  (not (setq result (gnus-topic-find-topology
+				     topic (car topology) (1+ level)
+				     (and remove top)))))
+	(setq topology (cdr topology)))
+      result)))
+
+(defvar gnus-tmp-topics nil)
+(defun gnus-topic-list (&optional topology)
+  "Return a list of all topics in the topology."
+  (unless topology
+    (setq topology gnus-topic-topology 
+	  gnus-tmp-topics nil))
+  (push (caar topology) gnus-tmp-topics)
+  (mapcar 'gnus-topic-list (cdr topology))
+  gnus-tmp-topics)
+
+;;; Topic parameter jazz
+
+(defun gnus-topic-parameters (topic)
+  "Return the parameters for TOPIC."
+  (let ((top (gnus-topic-find-topology topic)))
+    (unless top
+      (error "No such topic: %s" topic))
+    (nth 3 (cadr top))))
+
+(defun gnus-topic-set-parameters (topic parameters)
+  "Set the topic parameters of TOPIC to PARAMETERS."
+  (let ((top (gnus-topic-find-topology topic)))
+    (unless top
+      (error "No such topic: %s" topic))
+    ;; We may have to extend if there is no parameters here
+    ;; to begin with.
+    (unless (nthcdr 2 (cadr top))
+      (nconc (cadr top) (list nil)))
+    (unless (nthcdr 3 (cadr top))
+      (nconc (cadr top) (list nil)))
+    (setcar (nthcdr 3 (cadr top)) parameters)))
+
+(defun gnus-group-topic-parameters (group)
+  "Compute the group parameters for GROUP taking into account inheritance from topics."
+  (let ((params-list (list (gnus-group-get-parameter group)))
+	topics params param out)
+    (save-excursion
+      (gnus-group-goto-group group)
+      (setq topics (gnus-current-topics))
+      (while topics
+	(push (gnus-topic-parameters (pop topics)) params-list))
+      ;; We probably have lots of nil elements here, so
+      ;; we remove them.  Probably faster than doing this "properly".
+      (setq params-list (delq nil params-list))
+      ;; Now we have all the parameters, so we go through them
+      ;; and do inheritance in the obvious way.
+      (while (setq params (pop params-list))
+	(while (setq param (pop params))
+	  (when (atom param)
+	    (setq param (cons param t)))
+	  ;; Override any old versions of this param.
+	  (setq out (delq (assq (car param) out) out))
+	  (push param out)))
+      ;; Return the resulting parameter list.
+      out)))
+
+;;; General utility functions
+
+(defun gnus-topic-enter-dribble ()
+  (gnus-dribble-enter
+   (format "(setq gnus-topic-topology '%S)" gnus-topic-topology)))
+
+;;; Generating group buffers
 
 (defun gnus-group-prepare-topics (level &optional all lowest regexp list-topic topic-level)
   "List all newsgroups with unread articles of level LEVEL or lower, and
@@ -114,7 +336,8 @@ If LOWEST is non-nil, list all newsgroups of level LOWEST or higher."
 
     (setq gnus-topic-tallied-groups nil)
 
-    (unless gnus-topic-alist
+    (when (or (not gnus-topic-alist)
+	      (not gnus-topology-checked-p))
       (gnus-topic-check-topology))
 
     (unless list-topic 
@@ -123,7 +346,7 @@ If LOWEST is non-nil, list all newsgroups of level LOWEST or higher."
     ;; List dead groups?
     (when (and (>= level gnus-level-zombie) (<= lowest gnus-level-zombie))
       (gnus-group-prepare-flat-list-dead 
-       (setq gnus-zombie-list (sort gnus-zombie-list 'string<)) 
+       (setq gnus-zombie-list (sort gnus-zombie-list 'string<))
        gnus-level-zombie ?Z
        regexp))
     
@@ -177,12 +400,13 @@ articles in the topic and its subtopics."
 	    (gnus-group-insert-group-line
 	     entry (if (member entry gnus-zombie-list) 8 9)
 	     nil (- (1+ (cdr (setq active (gnus-active entry))))
-		    (car active)) nil)
+		    (car active))
+	     nil)
 	  ;; Living groups.
 	  (when (setq info (nth 2 entry))
 	    (gnus-group-insert-group-line 
 	     (gnus-info-group info)
-	     (gnus-info-level info) (gnus-info-marks info) 
+	     (gnus-info-level info) (gnus-info-marks info)
 	     (car entry) (gnus-info-method info)))))
       (when (and (listp entry)
 		 (numberp (car entry))
@@ -192,7 +416,9 @@ articles in the topic and its subtopics."
 	(incf unread (car entry))))
     (goto-char beg)
     ;; Insert the topic line.
-    (unless silent
+    (when (and (not silent)
+	       (or gnus-topic-display-empty-topics
+		   (not (zerop unread))))
       (gnus-extent-start-open (point))
       (gnus-topic-insert-topic-line 
        (car type) visiblep
@@ -201,44 +427,6 @@ articles in the topic and its subtopics."
     (goto-char end)
     unread))
 
-(defun gnus-topic-find-groups (topic &optional level all)
-  "Return entries for all visible groups in TOPIC."
-  (let ((groups (cdr (assoc topic gnus-topic-alist)))
-        info clevel unread group lowest params visible-groups entry active)
-    (setq lowest (or lowest 1))
-    (setq level (or level 7))
-    ;; We go through the newsrc to look for matches.
-    (while groups
-      (setq entry (gnus-gethash (setq group (pop groups)) gnus-newsrc-hashtb)
-	    info (nth 2 entry)
-	    params (gnus-info-params info)
-	    active (gnus-active group)
-            unread (or (car entry)
-		       (and (not (equal group "dummy.group"))
-			    active
-			    (- (1+ (cdr active)) (car active))))
-	    clevel (or (gnus-info-level info)
-		       (if (member group gnus-zombie-list) 8 9)))
-      (and 
-       unread				; nil means that the group is dead.
-       (<= clevel level) 
-       (>= clevel lowest)		; Is inside the level we want.
-       (or all
-	   (if (eq unread t)
-	       gnus-group-list-inactive-groups
-	     (> unread 0))
-	   (and gnus-list-groups-with-ticked-articles
-		(cdr (assq 'tick (gnus-info-marks info))))
-					; Has right readedness.
-	   ;; Check for permanent visibility.
-	   (and gnus-permanently-visible-groups
-		(string-match gnus-permanently-visible-groups group))
-	   (memq 'visible params)
-	   (cdr (assq 'visible params)))
-       ;; Add this group to the list of visible groups.
-       (push (or entry group) visible-groups)))
-    (nreverse visible-groups)))
-
 (defun gnus-topic-remove-topic (&optional insert total-remove hide in-level)
   "Remove the current topic."
   (let ((topic (gnus-group-topic-name))
@@ -249,12 +437,18 @@ articles in the topic and its subtopics."
       (while (and (zerop (forward-line 1))
 		  (> (or (gnus-group-topic-level) (1+ level)) level)))
       (delete-region beg (point))
-      (setcar (cdadr (gnus-topic-find-topology topic))
-	      (if insert 'visible 'invisible))
-      (when hide
-	(setcdr (cdadr (gnus-topic-find-topology topic))
-		(list hide)))
-      (unless total-remove
+      ;; Do the change in this rather odd manner because it has been
+      ;; reported that some topics share parts of some lists, for some
+      ;; reason.  I have been unable to determine why this is the
+      ;; case, but this hack seems to take care of things.
+      (let ((data (cadr (gnus-topic-find-topology topic))))
+	(setcdr data
+		(list (if insert 'visible 'invisible)
+		      (if hide 'hide nil)
+		      (cadddr data))))
+      (if total-remove
+	  (setq gnus-topic-alist
+		(delq (assoc topic gnus-topic-alist) gnus-topic-alist))
 	(gnus-topic-insert-topic topic in-level)))))
 
 (defun gnus-topic-insert-topic (topic &optional level)
@@ -265,7 +459,7 @@ articles in the topic and its subtopics."
   
 (defun gnus-topic-fold (&optional insert)
   "Remove/insert the current topic."
-  (let ((topic (gnus-group-topic-name))) 
+  (let ((topic (gnus-group-topic-name)))
     (when topic
       (save-excursion
 	(if (not (gnus-group-active-topic-p))
@@ -277,14 +471,6 @@ articles in the topic and its subtopics."
 	    (gnus-topic-remove-topic
 	     (or insert (not (gnus-topic-visible-p))) nil nil 9)))))))
 
-(defun gnus-group-topic-p ()
-  "Return non-nil if the current line is a topic."
-  (gnus-group-topic-name))
-
-(defun gnus-topic-visible-p ()
-  "Return non-nil if the current topic is visible."
-  (get-text-property (gnus-point-at-bol) 'gnus-topic-visible))
-
 (defun gnus-topic-insert-topic-line (name visiblep shownp level entries 
 					  &optional unread)
   (let* ((visible (if visiblep "" "..."))
@@ -296,7 +482,7 @@ articles in the topic and its subtopics."
     ;; Insert the text.
     (gnus-add-text-properties 
      (point)
-     (prog1 (1+ (point)) 
+     (prog1 (1+ (point))
        (eval gnus-topic-line-format-spec)
        (gnus-topic-remove-excess-properties)1)
      (list 'gnus-topic (intern name)
@@ -305,166 +491,49 @@ articles in the topic and its subtopics."
 	   'gnus-active active-topic
 	   'gnus-topic-visible visiblep))))
 
-(defun gnus-topic-previous-topic (topic)
-  "Return the previous topic on the same level as TOPIC."
-  (let ((top (cddr (gnus-topic-find-topology
-		    (gnus-topic-parent-topic topic)))))
-    (unless (equal topic (caaar top))
-      (while (and top (not (equal (caaadr top) topic)))
-	(setq top (cdr top)))
-      (caaar top))))
-
-(defun gnus-topic-parent-topic (topic &optional topology)
-  "Return the parent of TOPIC."
-  (unless topology
-    (setq topology gnus-topic-topology))
-  (let ((parent (car (pop topology)))
-	result found)
-    (while (and topology
-		(not (setq found (equal (caaar topology) topic)))
-		(not (setq result (gnus-topic-parent-topic topic 
-							   (car topology)))))
-      (setq topology (cdr topology)))
-    (or result (and found parent))))
-
-(defun gnus-topic-next-topic (topic &optional previous)
-  "Return the next sibling of TOPIC."
-  (let ((topology gnus-topic-topology)
-	(parentt (cddr (gnus-topic-find-topology 
-			(gnus-topic-parent-topic topic))))
-	prev)
-    (while (and parentt
-		(not (equal (caaar parentt) topic)))
-      (setq prev (caaar parentt)
-	    parentt (cdr parentt)))
-    (if previous
-	prev
-      (caaadr parentt))))
-
-(defun gnus-topic-find-topology (topic &optional topology level remove)
-  "Return the topology of TOPIC."
-  (unless topology
-    (setq topology gnus-topic-topology)
-    (setq level 0))
-  (let ((top topology)
-	result)
-    (if (equal (caar topology) topic)
-	(progn
-	  (when remove
-	    (delq topology remove))
-	  (cons level topology))
-      (setq topology (cdr topology))
-      (while (and topology
-		  (not (setq result (gnus-topic-find-topology
-				     topic (car topology) (1+ level)
-				     (and remove top)))))
-	(setq topology (cdr topology)))
-      result)))
-
-(gnus-add-shutdown 'gnus-topic-close 'gnus)
-
-(defun gnus-topic-close ()
-  (setq gnus-topic-active-topology nil
-	gnus-topic-active-alist nil
-	gnus-topic-killed-topics nil
-	gnus-topic-tallied-groups nil))
-
-(defun gnus-topic-check-topology ()  
-  ;; The first time we set the topology to whatever we have
-  ;; gotten here, which can be rather random.
-  (unless gnus-topic-alist
-    (gnus-topic-init-alist))
-
-  (let ((topics (gnus-topic-list))
-	(alist gnus-topic-alist)
-	changed)
-    (while alist
-      (unless (member (caar alist) topics)
-	(nconc gnus-topic-topology
-	       (list (list (list (caar alist) 'visible))))
-	(setq changed t))
-      (setq alist (cdr alist)))
-    (when changed
-      (gnus-topic-enter-dribble)))
-  (let* ((tgroups (apply 'append (mapcar (lambda (entry) (cdr entry))
-					 gnus-topic-alist)))
-	 (entry (assoc (caar gnus-topic-topology) gnus-topic-alist))
-	 (newsrc gnus-newsrc-alist)
-	 group)
-    (while newsrc
-      (unless (member (setq group (gnus-info-group (pop newsrc))) tgroups)
-	(setcdr entry (cons group (cdr entry)))))))
-
-(defvar gnus-tmp-topics nil)
-(defun gnus-topic-list (&optional topology)
-  (unless topology
-    (setq topology gnus-topic-topology 
-	  gnus-tmp-topics nil))
-  (push (caar topology) gnus-tmp-topics)
-  (mapcar 'gnus-topic-list (cdr topology))
-  gnus-tmp-topics)
-
-(defun gnus-topic-enter-dribble ()
-  (gnus-dribble-enter
-   (format "(setq gnus-topic-topology '%S)" gnus-topic-topology)))
-
-(defun gnus-topic-articles-in-topic (entries)
-  (let ((total 0)
-	number)
-    (while entries
-      (when (numberp (setq number (car (pop entries))))
-	(incf total number)))
-    total))
-
-(defun gnus-group-parent-topic ()
-  "Return the topic the current group belongs in."
-  (let ((group (gnus-group-group-name)))
-    (if group
-	(gnus-group-topic group)
-      (gnus-group-topic-name))))
-
-(defun gnus-group-topic (group)
-  "Return the topic GROUP is a member of."
-  (let ((alist gnus-topic-alist)
-	out)
-    (while alist
-      (when (member group (cdar alist))
-	(setq out (caar alist)
-	      alist nil))
-      (setq alist (cdr alist)))
-    out))
+(defun gnus-topic-update-topics-containing-group (group)
+  "Update all topics that have GROUP as a member."
+  (when (and (eq major-mode 'gnus-group-mode)
+	     gnus-topic-mode)
+    (save-excursion
+      (let ((alist gnus-topic-alist))
+	;; This is probably not entirely correct.  If a topic
+	;; isn't shown, then it's not updated.  But the updating
+	;; should be performed in any case, since the topic's
+	;; parent should be updated.  Pfft.
+	(while alist
+	  (when (and (member group (cdar alist))
+		     (gnus-topic-goto-topic (caar alist)))
+	    (gnus-topic-update-topic-line (caar alist)))
+	  (pop alist))))))
 
-(defun gnus-topic-goto-topic (topic)
-  (when topic
-    (gnus-goto-char (text-property-any (point-min) (point-max)
-				       'gnus-topic (intern topic)))))
-  
 (defun gnus-topic-update-topic ()
   "Update all parent topics to the current group."
   (when (and (eq major-mode 'gnus-group-mode)
 	     gnus-topic-mode)
     (let ((group (gnus-group-group-name))
 	  (buffer-read-only nil))
-      (when (and group (gnus-get-info group)
-		 (gnus-topic-goto-topic (gnus-group-parent-topic)))
+      (when (and group 
+		 (gnus-get-info group)
+		 (gnus-topic-goto-topic (gnus-current-topic)))
 	(gnus-topic-update-topic-line (gnus-group-topic-name))
 	(gnus-group-goto-group group)
 	(gnus-group-position-point)))))
 
-(defun gnus-topic-goto-missing-group (group) 
+(defun gnus-topic-goto-missing-group (group)
   "Place point where GROUP is supposed to be inserted."
   (let* ((topic (gnus-group-topic group))
 	 (groups (cdr (assoc topic gnus-topic-alist)))
 	 (g (cdr (member group groups)))
 	 (unfound t))
-    (while (and g unfound)
-      (when (gnus-group-goto-group (pop g))
-	(beginning-of-line)
-	(setq unfound nil)))
-    (when unfound
+    ;; Try to jump to a visible group.
+    (while (and g (not (gnus-group-goto-group (car g) t)))
+      (pop g))
+    ;; It wasn't visible, so we try to see where to insert it.
+    (when (not g)
       (setq g (cdr (member group (reverse groups))))
       (while (and g unfound)
-	(when (gnus-group-goto-group (pop g))
+	(when (gnus-group-goto-group (pop g) t)
 	  (forward-line 1)
 	  (setq unfound nil)))
       (when unfound
@@ -472,7 +541,9 @@ articles in the topic and its subtopics."
 	(forward-line 1)))))
 
 (defun gnus-topic-update-topic-line (topic-name &optional reads)
-  (let* ((type (cadr (gnus-topic-find-topology topic-name)))
+  (let* ((top (gnus-topic-find-topology topic-name))
+	 (type (cadr top))
+	 (children (cddr top))
 	 (entries (gnus-topic-find-groups 
 		   (car type) (car gnus-group-list-mode)
 		   (cdr gnus-group-list-mode)))
@@ -484,6 +555,8 @@ articles in the topic and its subtopics."
       ;; Tally all the groups that belong in this topic.
       (if reads
 	  (setq unread (- (gnus-group-topic-unread) reads))
+	(while children
+	  (incf unread (gnus-topic-unread (caar (pop children)))))
 	(while (setq entry (pop entries))
 	  (when (numberp (car entry))
 	    (incf unread (car entry)))))
@@ -500,6 +573,185 @@ articles in the topic and its subtopics."
        parent (- old-unread (gnus-group-topic-unread))))
     unread))
 
+(defun gnus-topic-group-indentation ()
+  (make-string 
+   (* gnus-topic-indent-level
+      (or (save-excursion
+	    (forward-line -1)
+	    (gnus-topic-goto-topic (gnus-current-topic))
+	    (gnus-group-topic-level))
+	  0))
+   ? ))
+
+;;; Initialization
+
+(gnus-add-shutdown 'gnus-topic-close 'gnus)
+
+(defun gnus-topic-close ()
+  (setq gnus-topic-active-topology nil
+	gnus-topic-active-alist nil
+	gnus-topic-killed-topics nil
+	gnus-topic-tallied-groups nil
+	gnus-topology-checked-p nil))
+
+(defun gnus-topic-check-topology ()
+  ;; The first time we set the topology to whatever we have
+  ;; gotten here, which can be rather random.
+  (unless gnus-topic-alist
+    (gnus-topic-init-alist))
+
+  (setq gnus-topology-checked-p t)
+  ;; Go through the topic alist and make sure that all topics
+  ;; are in the topic topology.
+  (let ((topics (gnus-topic-list))
+	(alist gnus-topic-alist)
+	changed)
+    (while alist
+      (unless (member (caar alist) topics)
+	(nconc gnus-topic-topology
+	       (list (list (list (caar alist) 'visible))))
+	(setq changed t))
+      (setq alist (cdr alist)))
+    (when changed
+      (gnus-topic-enter-dribble))
+    ;; Conversely, go through the topology and make sure that all
+    ;; topologies have alists.
+    (while topics
+      (unless (assoc (car topics) gnus-topic-alist)
+	(push (list (car topics)) gnus-topic-alist))
+      (pop topics)))
+  ;; Go through all living groups and make sure that
+  ;; they belong to some topic.
+  (let* ((tgroups (apply 'append (mapcar (lambda (entry) (cdr entry))
+					 gnus-topic-alist)))
+	 (entry (assoc (caar gnus-topic-topology) gnus-topic-alist))
+	 (newsrc gnus-newsrc-alist)
+	 group)
+    (while newsrc
+      (unless (member (setq group (gnus-info-group (pop newsrc))) tgroups)
+	(setcdr entry (cons group (cdr entry))))))
+  ;; Go through all topics and make sure they contain only living groups.
+  (let ((alist gnus-topic-alist)
+	topic)
+    (while (setq topic (pop alist))
+      (while (cdr topic)
+	(if (gnus-gethash (cadr topic) gnus-newsrc-hashtb)
+	    (setq topic (cdr topic))
+	  (setcdr topic (cddr topic)))))))
+
+(defun gnus-topic-init-alist ()
+  "Initialize the topic structures."
+  (setq gnus-topic-topology
+	(cons (list "Gnus" 'visible)
+	      (mapcar (lambda (topic)
+			(list (list (car topic) 'visible)))
+		      '(("misc")))))
+  (setq gnus-topic-alist
+	(list (cons "misc"
+		    (mapcar (lambda (info) (gnus-info-group info))
+			    (cdr gnus-newsrc-alist)))
+	      (list "Gnus")))
+  (gnus-topic-enter-dribble))
+
+;;; Maintenance
+
+(defun gnus-topic-clean-alist ()
+  "Remove bogus groups from the topic alist."
+  (let ((topic-alist gnus-topic-alist)
+	result topic)
+    (unless gnus-killed-hashtb
+      (gnus-make-hashtable-from-killed))
+    (while (setq topic (pop topic-alist))
+      (let ((topic-name (pop topic))
+	    group filtered-topic)
+	(while (setq group (pop topic))
+	  (when (and (or (gnus-gethash group gnus-active-hashtb)
+			 (gnus-info-method (gnus-get-info group)))
+		     (not (gnus-gethash group gnus-killed-hashtb)))
+	    (push group filtered-topic)))
+	(push (cons topic-name (nreverse filtered-topic)) result)))
+    (setq gnus-topic-alist (nreverse result))))
+
+(defun gnus-topic-change-level (group level oldlevel)
+  "Run when changing levels to enter/remove groups from topics."
+  (save-excursion
+    (set-buffer gnus-group-buffer)
+    (when (and gnus-topic-mode 
+	       gnus-topic-alist
+	       (not gnus-topic-inhibit-change-level))
+      ;; Remove the group from the topics.
+      (when (and (< oldlevel gnus-level-zombie)
+		 (>= level gnus-level-zombie))
+	(let (alist)
+	  (forward-line -1)
+	  (when (setq alist (assoc (gnus-current-topic) gnus-topic-alist))
+	    (setcdr alist (gnus-delete-first group (cdr alist))))))
+      ;; If the group is subscribed.  then we enter it into the topics.
+      (when (and (< level gnus-level-zombie)
+		 (>= oldlevel gnus-level-zombie))
+	(let* ((prev (gnus-group-group-name))
+	       (gnus-topic-inhibit-change-level t)
+	       (gnus-group-indentation
+		(make-string 
+		 (* gnus-topic-indent-level
+		    (or (save-excursion
+			  (gnus-topic-goto-topic (gnus-current-topic))
+			  (gnus-group-topic-level))
+			0))
+		 ? ))
+	       (yanked (list group))
+	       alist talist end)
+	  ;; Then we enter the yanked groups into the topics they belong
+	  ;; to. 
+	  (when (setq alist (assoc (save-excursion
+				     (forward-line -1)
+				     (or
+				      (gnus-current-topic)
+				      (caar gnus-topic-topology)))
+				   gnus-topic-alist))
+	    (setq talist alist)
+	    (when (stringp yanked)
+	      (setq yanked (list yanked)))
+	    (if (not prev)
+		(nconc alist yanked)
+	      (if (not (cdr alist))
+		  (setcdr alist (nconc yanked (cdr alist)))
+		(while (and (not end) (cdr alist))
+		  (when (equal (cadr alist) prev)
+		    (setcdr alist (nconc yanked (cdr alist)))
+		    (setq end t))
+		  (setq alist (cdr alist)))
+		(unless end
+		  (nconc talist yanked))))))
+	(gnus-topic-update-topic)))))
+
+(defun gnus-topic-goto-next-group (group props)
+  "Go to group or the next group after group."
+  (if (null group)
+      (gnus-topic-goto-topic (symbol-name (cadr (memq 'gnus-topic props))))
+    (if (gnus-group-goto-group group)
+	t
+      ;; The group is no longer visible.
+      (let* ((list (assoc (gnus-group-topic group) gnus-topic-alist))
+	     (after (cdr (member group (cdr list)))))
+	;; First try to put point on a group after the current one.
+	(while (and after
+		    (not (gnus-group-goto-group (car after))))
+	  (setq after (cdr after)))
+	;; Then try to put point on a group before point.
+	(unless after
+	  (setq after (cdr (member group (reverse (cdr list)))))
+	  (while (and after 
+		      (not (gnus-group-goto-group (car after))))
+	    (setq after (cdr after))))
+	;; Finally, just put point on the topic.
+	(unless after
+	  (gnus-topic-goto-topic (car list))
+	  (setq after nil))
+	t))))
+
+;;; Topic-active functions
+
 (defun gnus-topic-grok-active (&optional force)
   "Parse all active groups and create topic structures for them."
   ;; First we make sure that we have really read the active file. 
@@ -512,7 +764,7 @@ articles in the topic and its subtopics."
 		gnus-active-hashtb)
       (setq groups (sort groups 'string<))
       ;; Init the variables.
-      (setq gnus-topic-active-topology '(("" visible)))
+      (setq gnus-topic-active-topology (list (list "" 'visible)))
       (setq gnus-topic-active-alist nil)
       ;; Descend the top-level hierarchy.
       (gnus-topic-grok-active-1 gnus-topic-active-topology groups)
@@ -550,12 +802,6 @@ articles in the topic and its subtopics."
     ;; to this topic.
     groups))
 
-(defun gnus-group-active-topic-p ()
-  "Return whether the current active comes from the active topics."
-  (save-excursion
-    (beginning-of-line)
-    (get-text-property (point) 'gnus-active)))
-
 ;;; Topic mode, commands and keymap.
 
 (defvar gnus-topic-mode-map nil)
@@ -565,34 +811,42 @@ articles in the topic and its subtopics."
   (setq gnus-topic-mode-map (make-sparse-keymap))
 
   ;; Override certain group mode keys.
-  (gnus-define-keys
-   gnus-topic-mode-map
-   "=" gnus-topic-select-group
-   "\r" gnus-topic-select-group
-   " " gnus-topic-read-group
-   "\C-k" gnus-topic-kill-group
-   "\C-y" gnus-topic-yank-group
-   "\M-g" gnus-topic-get-new-news-this-topic
-   "AT" gnus-topic-list-active
-   gnus-mouse-2 gnus-mouse-pick-topic)
+  (gnus-define-keys gnus-topic-mode-map
+    "=" gnus-topic-select-group
+    "\r" gnus-topic-select-group
+    " " gnus-topic-read-group
+    "\C-k" gnus-topic-kill-group
+    "\C-y" gnus-topic-yank-group
+    "\M-g" gnus-topic-get-new-news-this-topic
+    "AT" gnus-topic-list-active
+    "Gp" gnus-topic-edit-parameters
+    gnus-mouse-2 gnus-mouse-pick-topic)
 
   ;; Define a new submap.
-  (gnus-define-keys
-   (gnus-group-topic-map "T" gnus-group-mode-map)
-   "#" gnus-topic-mark-topic
-   "\M-#" gnus-topic-unmark-topic
-   "n" gnus-topic-create-topic
-   "m" gnus-topic-move-group
-   "D" gnus-topic-remove-group
-   "c" gnus-topic-copy-group
-   "h" gnus-topic-hide-topic
-   "s" gnus-topic-show-topic
-   "M" gnus-topic-move-matching
-   "C" gnus-topic-copy-matching
-   "\C-i" gnus-topic-indent
-   [tab] gnus-topic-indent
-   "r" gnus-topic-rename
-   "\177" gnus-topic-delete))
+  (gnus-define-keys (gnus-group-topic-map "T" gnus-group-mode-map)
+    "#" gnus-topic-mark-topic
+    "\M-#" gnus-topic-unmark-topic
+    "n" gnus-topic-create-topic
+    "m" gnus-topic-move-group
+    "D" gnus-topic-remove-group
+    "c" gnus-topic-copy-group
+    "h" gnus-topic-hide-topic
+    "s" gnus-topic-show-topic
+    "M" gnus-topic-move-matching
+    "C" gnus-topic-copy-matching
+    "\C-i" gnus-topic-indent
+    [tab] gnus-topic-indent
+    "r" gnus-topic-rename
+    "\177" gnus-topic-delete)
+
+  (gnus-define-keys (gnus-topic-sort-map "S" gnus-group-topic-map)
+    "s" gnus-topic-sort-groups
+    "a" gnus-topic-sort-groups-by-alphabet
+    "u" gnus-topic-sort-groups-by-unread
+    "l" gnus-topic-sort-groups-by-level
+    "v" gnus-topic-sort-groups-by-score
+    "r" gnus-topic-sort-groups-by-rank
+    "m" gnus-topic-sort-groups-by-method))
 
 (defun gnus-topic-make-menu-bar ()
   (unless (boundp 'gnus-topic-menu)
@@ -639,25 +893,35 @@ articles in the topic and its subtopics."
 	      minor-mode-map-alist))
       (add-hook 'gnus-summary-exit-hook 'gnus-topic-update-topic)
       (add-hook 'gnus-group-catchup-group-hook 'gnus-topic-update-topic)
-      (make-local-variable 'gnus-group-prepare-function)
-      (setq gnus-group-prepare-function 'gnus-group-prepare-topics)
-      (make-local-variable 'gnus-group-goto-next-group-function)
-      (setq gnus-group-goto-next-group-function 
-	    'gnus-topic-goto-next-group)
+      (set (make-local-variable 'gnus-group-prepare-function)
+	   'gnus-group-prepare-topics)
+      (set (make-local-variable 'gnus-group-get-parameter-function)
+	   'gnus-group-topic-parameters)
+      (set (make-local-variable 'gnus-group-goto-next-group-function)
+	   'gnus-topic-goto-next-group)
+      (set (make-local-variable 'gnus-group-indentation-function)
+	   'gnus-topic-group-indentation)
+      (set (make-local-variable 'gnus-group-update-group-function)
+	   'gnus-topic-update-topics-containing-group)
+      (set (make-local-variable 'gnus-group-sort-alist-function)
+	   'gnus-group-sort-topic)
       (setq gnus-group-change-level-function 'gnus-topic-change-level)
       (setq gnus-goto-missing-group-function 'gnus-topic-goto-missing-group)
-      (make-local-variable 'gnus-group-indentation-function)
-      (setq gnus-group-indentation-function
-	    'gnus-topic-group-indentation)
+      (gnus-make-local-hook 'gnus-check-bogus-groups-hook)
+      (add-hook 'gnus-check-bogus-groups-hook 'gnus-topic-clean-alist)
+      (setq gnus-topology-checked-p nil)
       ;; We check the topology.
-      (gnus-topic-check-topology)
+      (when gnus-newsrc-alist
+	(gnus-topic-check-topology))
       (run-hooks 'gnus-topic-mode-hook))
     ;; Remove topic infestation.
     (unless gnus-topic-mode
       (remove-hook 'gnus-summary-exit-hook 'gnus-topic-update-topic)
       (remove-hook 'gnus-group-change-level-function 
 		   'gnus-topic-change-level)
-      (setq gnus-group-prepare-function 'gnus-group-prepare-flat))
+      (remove-hook 'gnus-check-bogus-groups-hook 'gnus-topic-clean-alist)
+      (setq gnus-group-prepare-function 'gnus-group-prepare-flat)
+      (setq gnus-group-sort-alist-function 'gnus-group-sort-flat))
     (when redisplay
       (gnus-group-list-groups))))
     
@@ -665,7 +929,9 @@ articles in the topic and its subtopics."
   "Select this newsgroup.
 No article is selected automatically.
 If ALL is non-nil, already read articles become readable.
-If ALL is a number, fetch this number of articles."
+If ALL is a number, fetch this number of articles.
+
+If performed over a topic line, toggle folding the topic."
   (interactive "P")
   (if (gnus-group-topic-p)
       (let ((gnus-group-list-mode 
@@ -685,7 +951,9 @@ If the prefix argument ALL is non-nil, already read articles become
 readable.  IF ALL is a number, fetch this number of articles.  If the
 optional argument NO-ARTICLE is non-nil, no article will be
 auto-selected upon group entry.  If GROUP is non-nil, fetch that
-group."
+group.
+
+If performed over a topic line, toggle folding the topic."
   (interactive "P")
   (if (gnus-group-topic-p)
       (let ((gnus-group-list-mode 
@@ -697,10 +965,10 @@ group."
   (interactive 
    (list
     (read-string "New topic: ")
-    (gnus-group-parent-topic)))
+    (gnus-current-topic)))
   ;; Check whether this topic already exists.
   (when (gnus-topic-find-topology topic)
-    (error "Topic aleady exists"))
+    (error "Topic already exists"))
   (unless parent
     (setq parent (caar gnus-topic-topology)))
   (let ((top (cdr (gnus-topic-find-topology parent)))
@@ -721,36 +989,43 @@ group."
   (gnus-topic-goto-topic topic))
 
 (defun gnus-topic-move-group (n topic &optional copyp)
-  "Move the current group to a topic."
+  "Move the next N groups to TOPIC.
+If COPYP, copy the groups instead."
   (interactive
    (list current-prefix-arg
 	 (completing-read "Move to topic: " gnus-topic-alist nil t)))
   (let ((groups (gnus-group-process-prefix n))
 	(topicl (assoc topic gnus-topic-alist))
+	(start-group (progn (forward-line 1) (gnus-group-group-name)))
+	(start-topic (gnus-group-topic-name))
 	entry)
-    (mapcar (lambda (g) 
-	      (gnus-group-remove-mark g)
-	      (when (and
-		     (setq entry (assoc (gnus-group-topic g) gnus-topic-alist))
-		     (not copyp))
-		(setcdr entry (delete g (cdr entry))))
-	      (when topicl
-		(nconc topicl (list g))))
-	    groups)
-    (gnus-group-position-point))
-  (gnus-topic-enter-dribble)
-  (gnus-group-list-groups))
+    (mapcar 
+     (lambda (g)
+       (gnus-group-remove-mark g)
+       (when (and
+	      (setq entry (assoc (gnus-current-topic) gnus-topic-alist))
+	      (not copyp))
+	 (setcdr entry (gnus-delete-first g (cdr entry))))
+       (nconc topicl (list g)))
+     groups)
+    (gnus-topic-enter-dribble)
+    (if start-group
+	(gnus-group-goto-group start-group)
+      (gnus-topic-goto-topic start-topic))
+    (gnus-group-list-groups)))
 
-(defun gnus-topic-remove-group ()
+(defun gnus-topic-remove-group (&optional arg)
   "Remove the current group from the topic."
-  (interactive)
-  (let ((topicl (assoc (gnus-group-parent-topic) gnus-topic-alist))
-	(group (gnus-group-group-name))
-	(buffer-read-only nil))
-    (when (and topicl group)
-      (gnus-delete-line)
-      (delq (gnus-group-group-name) topicl))
-    (gnus-group-position-point)))
+  (interactive "P")
+  (gnus-group-iterate arg 
+    (lambda (group)
+      (let ((topicl (assoc (gnus-current-topic) gnus-topic-alist))
+	    (buffer-read-only nil))
+	(when (and topicl group)
+	  (gnus-delete-line)
+	  (gnus-delete-first group topicl))
+	(gnus-topic-update-topic)
+	(gnus-group-position-point)))))
 
 (defun gnus-topic-copy-group (n topic)
   "Copy the current group to a topic."
@@ -759,86 +1034,6 @@ group."
 	 (completing-read "Copy to topic: " gnus-topic-alist nil t)))
   (gnus-topic-move-group n topic t))
 
-(defun gnus-topic-group-indentation ()
-  (make-string 
-   (* gnus-topic-indent-level
-      (or (save-excursion
-	    (gnus-topic-goto-topic (gnus-group-parent-topic))
-	    (gnus-group-topic-level)) 0)) ? ))
-
-(defun gnus-topic-change-level (group level oldlevel)
-  "Run when changing levels to enter/remove groups from topics."
-  (when (and gnus-topic-mode 
-	     gnus-topic-alist
-	     (not gnus-topic-inhibit-change-level))
-    ;; Remove the group from the topics.
-    (when (and (< oldlevel gnus-level-zombie)
-	       (>= level gnus-level-zombie))
-      (let (alist)
-	(when (setq alist (assoc (gnus-group-topic group) gnus-topic-alist))
-	  (setcdr alist (delete group (cdr alist))))))
-    ;; If the group is subscribed. then we enter it into the topics.
-    (when (and (< level gnus-level-zombie)
-	       (>= oldlevel gnus-level-zombie))
-      (let* ((prev (gnus-group-group-name))
-	     (gnus-topic-inhibit-change-level t)
-	     (gnus-group-indentation
-	      (make-string 
-	       (* gnus-topic-indent-level
-		  (or (save-excursion
-			(gnus-topic-goto-topic (gnus-group-parent-topic))
-			(gnus-group-topic-level)) 0)) ? ))
-	     (yanked (list group))
-	     alist talist end)
-	;; Then we enter the yanked groups into the topics they belong
-	;; to. 
-	(when (setq alist (assoc (save-excursion
-				   (forward-line -1)
-				   (or
-				    (gnus-group-parent-topic)
-				    (caar gnus-topic-topology)))
-				 gnus-topic-alist))
-	  (setq talist alist)
-	  (when (stringp yanked)
-	    (setq yanked (list yanked)))
-	  (if (not prev)
-	      (nconc alist yanked)
-	    (if (not (cdr alist))
-		(setcdr alist (nconc yanked (cdr alist)))
-	      (while (and (not end) (cdr alist))
-		(when (equal (cadr alist) prev)
-		  (setcdr alist (nconc yanked (cdr alist)))
-		  (setq end t))
-		(setq alist (cdr alist)))
-	      (unless end
-		(nconc talist yanked))))))
-      (gnus-topic-update-topic))))
-
-(defun gnus-topic-goto-next-group (group props)
-  "Go to group or the next group after group."
-  (if (null group)
-      (gnus-topic-goto-topic (symbol-name (cadr (memq 'gnus-topic props))))
-    (if (gnus-group-goto-group group)
-	t
-      ;; The group is no longer visible.
-      (let* ((list (assoc (gnus-group-topic group) gnus-topic-alist))
-	     (after (cdr (member group (cdr list)))))
-	;; First try to put point on a group after the current one.
-	(while (and after
-		    (not (gnus-group-goto-group (car after))))
-	  (setq after (cdr after)))
-	;; Then try to put point on a group before point.
-	(unless after
-	  (setq after (cdr (member group (reverse (cdr list)))))
-	  (while (and after 
-		      (not (gnus-group-goto-group (car after))))
-	    (setq after (cdr after))))
-	;; Finally, just put point on the topic.
-	(unless after
-	  (gnus-topic-goto-topic (car list))
-	  (setq after nil))
-	t))))
-
 (defun gnus-topic-kill-group (&optional n discard)
   "Kill the next N groups."
   (interactive "P")
@@ -846,7 +1041,8 @@ group."
       (let ((topic (gnus-group-topic-name)))
 	(gnus-topic-remove-topic nil t)
 	(push (gnus-topic-find-topology topic nil nil gnus-topic-topology)
-	      gnus-topic-killed-topics))
+	      gnus-topic-killed-topics)
+	(gnus-topic-enter-dribble))
     (gnus-group-kill-group n discard)
     (gnus-topic-update-topic)))
   
@@ -854,11 +1050,14 @@ group."
   "Yank the last topic."
   (interactive "p")
   (if gnus-topic-killed-topics
-      (let ((previous (gnus-group-parent-topic))
+      (let ((previous 
+	     (or (gnus-group-topic-name)
+		 (gnus-topic-next-topic (gnus-current-topic))))
 	    (item (cdr (pop gnus-topic-killed-topics))))
 	(gnus-topic-create-topic
 	 (caar item) (gnus-topic-parent-topic previous) previous
 	 item)
+	(gnus-topic-enter-dribble)
 	(gnus-topic-goto-topic (caar item)))
     (let* ((prev (gnus-group-group-name))
 	   (gnus-topic-inhibit-change-level t)
@@ -866,8 +1065,10 @@ group."
 	    (make-string 
 	     (* gnus-topic-indent-level
 		(or (save-excursion
-		      (gnus-topic-goto-topic (gnus-group-parent-topic))
-		      (gnus-group-topic-level)) 0)) ? ))
+		      (gnus-topic-goto-topic (gnus-current-topic))
+		      (gnus-group-topic-level))
+		    0))
+	     ? ))
 	   yanked alist)
       ;; We first yank the groups the normal way...
       (setq yanked (gnus-group-yank-group arg))
@@ -875,7 +1076,7 @@ group."
       ;; to. 
       (setq alist (assoc (save-excursion
 			   (forward-line -1)
-			   (gnus-group-parent-topic))
+			   (gnus-current-topic))
 			 gnus-topic-alist))
       (when (stringp yanked)
 	(setq yanked (list yanked)))
@@ -891,10 +1092,10 @@ group."
     (gnus-topic-update-topic)))
 
 (defun gnus-topic-hide-topic ()
-  "Hide all subtopics under the current topic."
+  "Hide the current topic."
   (interactive)
-  (when (gnus-group-parent-topic)
-    (gnus-topic-goto-topic (gnus-group-parent-topic))
+  (when (gnus-current-topic)
+    (gnus-topic-goto-topic (gnus-current-topic))
     (gnus-topic-remove-topic nil nil 'hidden)))
 
 (defun gnus-topic-show-topic ()
@@ -905,7 +1106,7 @@ group."
 
 (defun gnus-topic-mark-topic (topic &optional unmark)
   "Mark all groups in the topic with the process mark."
-  (interactive (list (gnus-group-parent-topic)))
+  (interactive (list (gnus-current-topic)))
   (save-excursion
     (let ((groups (gnus-topic-find-groups topic 9 t)))
       (while groups
@@ -914,7 +1115,7 @@ group."
 
 (defun gnus-topic-unmark-topic (topic &optional unmark)
   "Remove the process mark from all groups in the topic."
-  (interactive (list (gnus-group-parent-topic)))
+  (interactive (list (gnus-current-topic)))
   (gnus-topic-mark-topic topic t))
 
 (defun gnus-topic-get-new-news-this-topic (&optional n)
@@ -966,7 +1167,7 @@ group."
 (defun gnus-topic-rename (old-name new-name)
   "Rename a topic."
   (interactive
-   (let ((topic (gnus-group-parent-topic)))
+   (let ((topic (gnus-current-topic)))
      (list topic
 	   (read-string (format "Rename %s to: " topic)))))
   (let ((top (gnus-topic-find-topology old-name))
@@ -975,6 +1176,7 @@ group."
       (setcar (cadr top) new-name))
     (when entry 
       (setcar entry new-name))
+    (forward-line -1)
     (gnus-group-list-groups)))
 
 (defun gnus-topic-indent (&optional unindent)
@@ -983,7 +1185,7 @@ If UNINDENT, remove an indentation."
   (interactive "P")
   (if unindent
       (gnus-topic-unindent)
-    (let* ((topic (gnus-group-parent-topic))
+    (let* ((topic (gnus-current-topic))
 	   (parent (gnus-topic-previous-topic topic)))
       (unless parent
 	(error "Nothing to indent %s into" topic))
@@ -998,7 +1200,7 @@ If UNINDENT, remove an indentation."
 (defun gnus-topic-unindent ()
   "Unindent a topic."
   (interactive)
-  (let* ((topic (gnus-group-parent-topic))
+  (let* ((topic (gnus-current-topic))
 	 (parent (gnus-topic-parent-topic topic))
 	 (grandparent (gnus-topic-parent-topic parent)))
     (unless grandparent
@@ -1023,6 +1225,92 @@ If FORCE, always re-read the active file."
 	gnus-killed-list gnus-zombie-list)
     (gnus-group-list-groups 9 nil 1)))
 
+;;; Topic sorting functions
+
+(defun gnus-topic-edit-parameters (group)
+  "Edit the group parameters of GROUP.
+If performed on a topic, edit the topic parameters instead."
+  (interactive (list (gnus-group-group-name)))
+  (if group
+      (gnus-group-edit-group-parameters group)
+    (if (not (gnus-group-topic-p))
+	(error "Nothing to edit on the current line.")
+      (let ((topic (gnus-group-topic-name)))
+	(gnus-edit-form
+	 (gnus-topic-parameters topic)
+	 "Editing the topic parameters."
+	 `(lambda (form)
+	    (gnus-topic-set-parameters ,topic form)))))))
+
+(defun gnus-group-sort-topic (func reverse)
+  "Sort groups in the topics according to FUNC and REVERSE."
+  (let ((alist gnus-topic-alist))
+    (while alist
+      (gnus-topic-sort-topic (pop alist) func reverse))))
+
+(defun gnus-topic-sort-topic (topic func reverse)
+  ;; Each topic only lists the name of the group, while
+  ;; the sort predicates expect group infos as inputs.
+  ;; So we first transform the group names into infos,
+  ;; then sort, and then transform back into group names.
+  (setcdr
+   topic
+   (mapcar
+    (lambda (info) (gnus-info-group info))
+    (sort
+     (mapcar
+      (lambda (group) (gnus-get-info group))
+      (cdr topic))
+     func)))
+  ;; Do the reversal, if necessary.
+  (when reverse
+    (setcdr topic (nreverse (cdr topic)))))
+
+(defun gnus-topic-sort-groups (func &optional reverse)
+  "Sort the current topic according to FUNC.
+If REVERSE, reverse the sorting order."
+  (interactive (list gnus-group-sort-function current-prefix-arg))
+  (let ((topic (assoc (gnus-current-topic) gnus-topic-alist)))
+    (gnus-topic-sort-topic
+     topic (gnus-make-sort-function func) reverse)
+    (gnus-group-list-groups)))
+
+(defun gnus-topic-sort-groups-by-alphabet (&optional reverse)
+  "Sort the current topic alphabetically by group name.
+If REVERSE, sort in reverse order."
+  (interactive "P")
+  (gnus-topic-sort-groups 'gnus-group-sort-by-alphabet reverse))
+
+(defun gnus-topic-sort-groups-by-unread (&optional reverse)
+  "Sort the current topic by number of unread articles.
+If REVERSE, sort in reverse order."
+  (interactive "P")
+  (gnus-topic-sort-groups 'gnus-group-sort-by-unread reverse))
+
+(defun gnus-topic-sort-groups-by-level (&optional reverse)
+  "Sort the current topic by group level.
+If REVERSE, sort in reverse order."
+  (interactive "P")
+  (gnus-topic-sort-groups 'gnus-group-sort-by-level reverse))
+
+(defun gnus-topic-sort-groups-by-score (&optional reverse)
+  "Sort the current topic by group score.
+If REVERSE, sort in reverse order."
+  (interactive "P")
+  (gnus-topic-sort-groups 'gnus-group-sort-by-score reverse))
+
+(defun gnus-topic-sort-groups-by-rank (&optional reverse)
+  "Sort the current topic by group rank.
+If REVERSE, sort in reverse order."
+  (interactive "P")
+  (gnus-topic-sort-groups 'gnus-group-sort-by-rank reverse))
+
+(defun gnus-topic-sort-groups-by-method (&optional reverse)
+  "Sort the current topic alphabetically by backend name.
+If REVERSE, sort in reverse order."
+  (interactive "P")
+  (gnus-topic-sort-groups 'gnus-group-sort-by-method reverse))
+
 (provide 'gnus-topic)
 
 ;;; gnus-topic.el ends here