lyskom-rest.el

;;;;;
;;;;; $Id$
;;;;; Copyright (C) 1991, 1996  Lysator Academic Computer Association.
;;;;;
;;;;; This file is part of the LysKOM server.
;;;;; 
;;;;; LysKOM is free software; you can redistribute it and/or modify it
;;;;; under the terms of the GNU General Public License as published by 
;;;;; the Free Software Foundation; either version 2, or (at your option) 
;;;;; any later version.
;;;;; 
;;;;; LysKOM is distributed in the hope that it will be useful, but WITHOUT
;;;;; ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
;;;;; FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
;;;;; for more details.
;;;;; 
;;;;; You should have received a copy of the GNU General Public License
;;;;; along with LysKOM; see the file COPYING.  If not, write to
;;;;; Lysator, c/o ISY, Linkoping University, S-581 83 Linkoping, SWEDEN,
;;;;; or the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, 
;;;;; MA 02139, USA.
;;;;;
;;;;; Please mail bug reports to bug-lyskom@lysator.liu.se. 
;;;;;
;;;; ================================================================
;;;; ================================================================
;;;;
;;;; File: lyskom-rest.el
;;;;
;;;; This is the rest of what was once the entire source code of the
;;;; client. Now most of the source resides in other files. Eventually
;;;; the functions in here will be distributed out to other files.
;;;; Below follows the original header of the LysKOM elisp client:
;;;;
;;;; ================================================================
;;;;
;;;; Simple LysKOM elisp client.
;;;;
;;;; Originally written by Per Cederqvist.
;;;;
;;;; Heavily hacked by:
;;;;    Thomas Bellman
;;;;    Linus Tolke
;;;;    Inge Wallin
;;;;    David K}gedal
;;;;    David Byers
;;;;   and others.
;;;;
;;;; Some ideas stolen from lpmud.el written by Lars Willf|r and Thomas Bellman
;;;;
;;;; Conventions:
;;;;
;;;;    All functions, variables etc follow one of these conventions:
;;;;		lyskom-		general functions.
;;;;		cache-		cache-routines.
;;;;		initiate-	call a service. (Might look up in cache)
;;;;		kom-		user kommands.
;;;;		lyskom-parse-	parse (part of) a reply from the server.
;;;;				these are found in parse.el
;;;;		lyskom-edit-	Things related to the editing of texts.
;;;;		{lyskom,kom}-edit-options-
;;;;				things related to editing options
;;;;				(found in flags.el)
;;;;		{lyskom,kom}-prioritize-
;;;;				things related to the prioritize
;;;;				buffer. The file is prioritize.el
;;;;		{lyskom,kom}-{completing-read,completing,complete}-
;;;;				things related to
;;;;				lyskom-completing-read. Found in
;;;;				completing-read.el 
;;;;		lyskom-*-hook   hooks.
;;;;
;;;;    Three plus-signs (+++) in the code marks a place where more
;;;;    work is needed.
;;;;

(require 'lyskom-menus "menus")


(setq lyskom-clientversion-long 
      (concat lyskom-clientversion-long
	      "$Id$\n"))


;;;; ================================================================
;;;;                             New errors.


(put 'lyskom-protocol-error 'error-conditions
     '(error lyskom-error lyskom-protocol-error))
(put 'lyskom-protocol-error 'error-message
     "LysKOM protocol error:")

(put 'lyskom-internal-error 'error-conditions
     '(error lyskom-error lyskom-internal-error))
(put 'lyskom-internal-error 'error-message
     "Internal LysKOM error.")

(put 'lyskom-format-error 'error-conditions
     '(error lyskom-error lyskom-format-error))
(put 'lyskom-internal-error 'error-message
     "Internal LysKOM format error.")


;;; ================================================================
;;;             Global variables
;;;

(defvar lyskom-unread-mode-line nil)

;;; ================================================================
;;;             Error reporting from a number of commands.
;;;

;;; Author: Inge Wallin



(defun lyskom-get-error-text (errno)
  "Get a string which is the error ERRNO in plain text."
  (or
   (lyskom-get-string-internal (intern (concat "error-"
					       (number-to-string errno)))
			       'lyskom-error-texts)
   (lyskom-format 'error-not-found errno)))

(defun lyskom-report-command-answer (answer)
  "Handles a void return from call to the server."
  (if answer 
      (lyskom-insert-string 'done)
    (lyskom-insert-string 'nope)
    (lyskom-format-insert 'error-code
			  (lyskom-get-error-text lyskom-errno)
			  lyskom-errno)))


;;; ----------------------------------------------------------------
;;; Author: Aronsson

(defsubst lyskom-tell-string (key)
  "Retrieve the phrase indexed by the key from the kom-tell-phrases
assoc list."
  (lyskom-get-string key 'kom-tell-phrases))


(defun lyskom-tell-internat (key)
  "Same as lyskom-tell-server, but use a key to a list of phrases."
  ;; The server at Lysator produces a lot of network traffic. The
  ;; solution should to be less verbose. This is very interesting
  ;; anymore, anyway.
  (lyskom-tell-server (lyskom-tell-string key)))



;;; Resume operation after a crash.

(defun kom-recover (&optional refetch)
  "Try to recover from an error.
If the optional argument REFETCH is non-nil, `lyskom-refetch' is called."
  (interactive "p")
  (lyskom-init-parse lyskom-buffer)
  (setq lyskom-call-data nil)
  (setq lyskom-pending-calls nil)
  (setq lyskom-output-queues (make-vector 10 nil))
  (let ((i 0))
    (while (< i 10)
      (aset lyskom-output-queues i (lyskom-queue-create))
      (++ i)))
  (setq lyskom-number-of-pending-calls 0)
  (setq lyskom-is-parsing nil)
  (if refetch (lyskom-refetch))
  (lyskom-tell-internat 'kom-tell-recover)
  (lyskom-end-of-command))


;;; ================================================================
;;;                      Run default command.


;;; Author: Tommy Persson

(defun kom-page-next-command ()
  "Scroll the bottom to the top and run the next command if it should be run"
  (interactive)
  (if (pos-visible-in-window-p (point-max))
      (progn
	(goto-char (point-max))
	(recenter 0)
	(lyskom-next-command))
    (recenter 0)
    (move-to-window-line -1)
    (lyskom-set-last-viewed)))


;;; Author: Lars Willf|r

(defun kom-next-command ()
  "Run next command or scroll one page."
  (interactive)
  (if (pos-visible-in-window-p (point-max))
      (lyskom-next-command)
    (move-to-window-line -1)
    (lyskom-set-last-viewed)
    (lyskom-scroll)))

  
(defun kom-line-next-command ()
  "Run next command or scroll one line."
  (interactive)
  (if (pos-visible-in-window-p (point-max))
      (lyskom-next-command)
    (move-to-window-line 1)
    (lyskom-set-last-viewed)
    (lyskom-scroll)))


;;; Author: Per Cederqvist

(defun lyskom-next-command ()
  "Run next command."
  (let ((lyskom-doing-default-command t))
    (cond
     ((eq lyskom-command-to-do 'next-pri-text)
      (lyskom-view-priority-text))
     ((eq lyskom-command-to-do 'next-text)
      (kom-view-next-text))
     ((eq lyskom-command-to-do 'next-conf)
      (kom-go-to-next-conf))
     ((eq lyskom-command-to-do 'next-pri-conf)
      (lyskom-go-to-pri-conf))
     ((eq lyskom-command-to-do 'when-done)
      (let ((command (lyskom-what-to-do-when-done)))
	(cond
	 ((or (stringp command)
              (vectorp command))
	  (execute-kbd-macro command))
	 (t (call-interactively command)))))
     ((eq lyskom-command-to-do 'unknown)
      (lyskom-insert
       (lyskom-get-string 'wait-for-server)))
     (t (signal 'lyskom-internal-error '(kom-next-command))))))


;;; ================================================================
;;;                              View text.


(defun kom-initial-digit-view ()
  (interactive)
  (setq unread-command-events (cons last-command-event
                                    unread-command-events))
  (call-interactively 'kom-view nil))


(defun kom-view (text-no)
  "View text number TEXT-NO."
  (interactive "P")
  (unwind-protect
      (progn
	(let ((kom-page-before-command nil))
	  (lyskom-start-of-command 'kom-view)
	  (lyskom-tell-internat 'kom-tell-review)
	  )
	(if (setq text-no (cond ((null text-no) nil)
				((listp text-no) (car text-no))
				(t text-no)))
	    nil
	  (setq text-no (lyskom-read-number (lyskom-get-string 'review-text-q)
					    lyskom-current-text)))
	(if (or (not (listp kom-page-before-command))
		(memq 'kom-view kom-page-before-command))
	    (recenter 1))
	(lyskom-tell-internat 'kom-tell-review)
	(lyskom-format-insert 'review-text-no text-no)
	(lyskom-view-text text-no))
    (lyskom-end-of-command)))


;;;; ================================================================
;;;;                         View next text.


(defun kom-view-next-new-text ()
  "Display next new text (putting all review constructs at the end of this conf)."
  (interactive)
  (let ((len (read-list-length lyskom-reading-list))
	(finished nil))
    (while (and (not finished)
		(> len 1))
      (let ((type (read-info->type (read-list->first lyskom-reading-list))))
	(cond 
	 ((or (eq type 'REVIEW)
	      (eq type 'REVIEW-TREE)
	      (eq type 'REVIEW-MARK))
	  (read-list-rotate lyskom-reading-list))
	 ((or (eq type 'COMM-IN)
	      (eq type 'FOOTN-IN))
	  (set-read-list-del-first lyskom-reading-list))
	 (t 
	  (setq finished t))))
      (-- len)))
  (kom-view-next-text))


;;; Modified to handle filters

(def-kom-command kom-view-next-text ()
  "Display next text (from lyskom-reading-list)."
  (interactive)
  (lyskom-tell-internat 'kom-tell-read)
  (let ((action 'next-text))
    (while (eq action 'next-text)
      (if (read-list-isempty lyskom-reading-list)
	  (progn
	    (if (/= 0 lyskom-current-conf)
		(lyskom-insert-string 'completely-read-conf)
	      (lyskom-insert-string 'not-in-any-conf))
	    (setq action nil))
	      
	(progn
	  (let* ((tri (read-list->first lyskom-reading-list))
		 (text-no (car (cdr (read-info->text-list tri))))
		 (type (read-info->type tri))
		 (priority (read-info->priority
			    (read-list->first lyskom-reading-list)))
		 (is-review-tree (eq type 'REVIEW-TREE))
		 (is-review (or (eq type 'REVIEW)
				(eq type 'REVIEW-MARK)
				is-review-tree))
		 (mark-as-read (not is-review)))
	    (if is-review
		(delq text-no 
		      (read-info->text-list tri))) ;First entry only
	    (setq action
		  (lyskom-view-text text-no mark-as-read 
				    (and kom-read-depth-first
					 (not is-review))
				    (read-info->conf-stat
				     (read-list->first
				      lyskom-reading-list))
				    priority
				    is-review-tree
				    (not is-review)))
	    (if mark-as-read
		(lyskom-is-read text-no)
	      (read-list-delete-text nil lyskom-reading-list)
	      (read-list-delete-text nil lyskom-to-do-list))))))))
  

;;; Modified to handle filters

;; This is horribly ugly. It acts like a user command, but it isn't.
(defun lyskom-view-priority-text ()
  "Display the first text from the next conference on the lyskom-to-do-list."
  (lyskom-start-of-command 'kom-view-next-text)
  (unwind-protect
      (progn
	(lyskom-tell-internat 'kom-tell-read)
	(let* ((tri (read-list->first lyskom-to-do-list))
	       (priority (read-info->priority
			  (read-list->first lyskom-reading-list)))
	       (text-no (car (text-list->texts (read-info->text-list tri)))))
	  (lyskom-is-read text-no)
	  (lyskom-view-text text-no t nil (read-info->conf-stat tri) 
			    priority nil t))
	(lyskom-wait-queue 'main))
    (lyskom-end-of-command)))


(defun lyskom-is-read (text-no)
  "Remove TEXT-NO from the list of texts to read.
Deletes TEXT-NO from lyskom-reading-list and lyskom-to-do-list.
Adds info in lyskom-membership.

This function only modifies the internal state of the client. It does
not mark the text as read in the server. That function is performed by
lyskom-mark-as-read."
  (read-list-delete-text text-no lyskom-reading-list)
  (read-list-delete-text text-no lyskom-to-do-list)
  (initiate-get-text-stat 'main 'lyskom-is-read-handler text-no)
  (setq lyskom-normally-read-texts (cons text-no lyskom-normally-read-texts)))


(defun lyskom-is-read-handler (text-stat)
  "Update lyskom-membership for all recipients to TEXT-STAT."
  (lyskom-traverse
      misc (text-stat->misc-info-list text-stat)
    (if (or (eq 'RECPT (misc-info->type misc))
	    (eq 'CC-RECPT (misc-info->type misc)))
	(let ((membership (lyskom-try-get-membership
			   (misc-info->recipient-no misc))))
	  (if membership
	      (set-membership->read-texts
	       membership
	       (vconcat (vector (misc-info->local-no misc))
			(membership->read-texts membership))))))))


;;; ================================================================
;;;                        Go to next conf.


(def-kom-command kom-go-to-next-conf ()
  "Go to next conf.
Take first conf from lyskom-to-do-list and copy it to lyskom-reading-list.
Tell server what the user is doing. If the user is reading a conf it is
moved last on lyskom-to-do-list, with priority 0."
  (interactive)
  (lyskom-maybe-move-unread t)
  (lyskom-go-to-next-conf))


(defun lyskom-go-to-pri-conf ()
  "Go to the conf with higher priority.
This differs from kom-go-to-next-conf only in the place where the yet unread 
in the current conf is placed."
  (lyskom-start-of-command 'kom-go-to-next-conf)
  (lyskom-maybe-move-unread nil)
  (lyskom-go-to-next-conf)
  (lyskom-end-of-command))


(defun lyskom-go-to-next-conf ()
  "Actually go to the next conference on the lyskom-to-do-list"
  ;; Copy first element on lyskom-to-do-list to lyskom-reading-list.
  (if (not (read-list-isempty lyskom-to-do-list))
      (progn
	(read-list-enter-first
	   (read-list->first lyskom-to-do-list)
	   lyskom-reading-list)

	;; Tell server which conf the user is reading.
	(let ((conf-stat (read-info->conf-stat
			  (read-list->first lyskom-reading-list))))
	  (when conf-stat
	    (lyskom-enter-conf
	     conf-stat 
	     (read-list->first lyskom-reading-list))
	    (lyskom-set-mode-line conf-stat))))
    (lyskom-insert-string 'all-conf-unread-r)
    (lyskom-set-mode-line (lyskom-get-string 'all-conf-unread-s))))


(defun lyskom-maybe-move-unread (bury)
  "Empty the reading list.
If the argument BURY is non-nil and there are unread artilces left in the
reading list then the conf is inserted last in the to do list."
  (if (not (read-list-isempty lyskom-reading-list))
      (progn
	(if bury
	    (let ((conf-no nil)
		  (r 0))
	      (while (and (not conf-no)
			  (< r (read-list-length lyskom-reading-list)))
		(if (eq (read-info->type (read-list->nth lyskom-reading-list 
							 r))
			'CONF)
		    (setq conf-no (conf-stat->conf-no 
				   (read-info->conf-stat
				    (read-list->nth lyskom-reading-list r))))
		  (++ r)))
	      (if conf-no
		  (progn
		    (read-list-delete-read-info conf-no lyskom-to-do-list)
		    (read-list-enter-first (read-list->nth lyskom-reading-list
							   r)
					   lyskom-to-do-list)
		    (read-list-rotate lyskom-to-do-list)))))
	(set-read-list-empty lyskom-reading-list))))


(defun lyskom-enter-conf (conf-stat read-info)
  "Tell server which conf the user is reading.
Prints the name and amount of unread in the conference we just went to 
according to the value of kom-print-number-of-unread-on-entrance.
Args: CONF-STAT READ-INFO"
  (initiate-pepsi 'main nil (conf-stat->conf-no conf-stat))
  (setq lyskom-current-conf (conf-stat->conf-no conf-stat))
  (let ((num-unread (length (text-list->texts
			     (read-info->text-list
			      read-info)))))
    (lyskom-format-insert (if (not kom-print-number-of-unread-on-entrance)
			      'enter-conf
			    (if (= num-unread 1)
				'one-unread
			      'several-unread))
			  conf-stat
			  num-unread)))
  



;;;================================================================

;;; in vars.el:
;(defvar lyskom-sessions-with-unread nil
;  "Global variable. List of lyskom-sessions with unread articles.")
;;;Must be called after lyskom-get-string is defined. Also after running 
;;;load hooks.
;;;(or (assq 'lyskom-sessions-with-unread minor-mode-alist)
;;;    (setq minor-mode-alist (cons (list 'lyskom-sessions-with-unread 
;;;			       		  (lyskom-get-string 'mode-line-unread))
;;;				 minor-mode-alist)))


(defun lyskom-set-mode-line (&optional conf)
  "Sets mode-line-conf-name to the name of the optional argument conf CONF.
CONF can be a a conf-stat or a string."
  (let ((name (cond
	       ((null conf) 
		(if (zerop lyskom-current-conf)
		    (lyskom-get-string 'not-present-anywhere)
		  (initiate-get-conf-stat 'modeline 'lyskom-set-mode-line
					  lyskom-current-conf)
		  nil))
	       ((stringp conf) conf)
	       ((lyskom-conf-stat-p conf)
		(conf-stat->name conf))
	       (t "")))
	(unread -1)
	(total-unread 0)
	(letters 0)
	(len 0)
	(read-info-list nil))

    (if (null name)
	nil				; We didn't have the name.

      ;; Set unread to the number of unread texts in CONF.
      (if (lyskom-conf-stat-p conf)
	  (progn
	    (setq read-info-list 
		  (read-list->all-entries lyskom-to-do-list))

	    ;; This was weird. Someone had begun to write an if, but
	    ;; this was all there was: (if 
	    (while read-info-list
	      (if (read-info->conf-stat (car read-info-list))
		  (progn
		    (setq len (length (text-list->texts 
				       (read-info->text-list 
					(car read-info-list)))))
		    (if (= (conf-stat->conf-no conf)
			   (conf-stat->conf-no 
			    (read-info->conf-stat (car read-info-list))))
			(setq unread len))
		    (if (= lyskom-pers-no
			   (conf-stat->conf-no 
			    (read-info->conf-stat (car read-info-list))))
			(setq letters len))
		    (setq total-unread (+ total-unread len))))
	      (setq read-info-list (cdr read-info-list)))))
      (if (= unread -1)
	  (setq unread 0))
      
      (if (null name)
	  nil
	(setq mode-line-conf-name 
	      (substring (concat
			  (if (lyskom-conf-stat-p conf)
			      (if (> lyskom-session-priority 0)
				  (format "(%d/%d:%d) "
					  unread total-unread
					  lyskom-session-priority)
				(format "(%d/%d) " unread total-unread))
			    "")
			  name
			  (make-string 27 ? ))
			 0 27)))
      
      (if (zerop total-unread)
	  (setq lyskom-sessions-with-unread
		(delq lyskom-buffer lyskom-sessions-with-unread))
	(or (memq lyskom-buffer lyskom-sessions-with-unread)
	    (setq lyskom-sessions-with-unread
		  (cons lyskom-buffer lyskom-sessions-with-unread))))
      (if (zerop letters)
	  (setq lyskom-sessions-with-unread-letters
		(delq lyskom-buffer lyskom-sessions-with-unread-letters))
	(or (memq lyskom-buffer lyskom-sessions-with-unread-letters)
	    (setq lyskom-sessions-with-unread-letters
		  (cons lyskom-buffer lyskom-sessions-with-unread-letters)))))
    (force-mode-line-update)))


;;; ================================================================

;;; +++Where should this be moved???


(defun lyskom-try-get-membership (conf-no)
  "Returns non-nil if conference CONF-NO is present on lyskom-membership.
The value is actually the membership for the conference.

For foreground functions, lyskom-get-membership should probably be used
instead.

This function does not use blocking-do."
  (let ((list lyskom-membership)
	(found nil))
    (while (and (not found) (not (null list)))
      (if (= conf-no (membership->conf-no (car list)))
	  (setq found (car list)))
      (setq list (cdr list)))
    found))


(defun lyskom-get-membership (conf-no)
  "Get the membership for CONF-NO, or nil if the user is not a member of
CONF-NO.

If the membership list is not fully prefetched and the membership can't be
found inlyskom-membership, a blocking call to the server is made."
  (or (lyskom-try-get-membership conf-no)
      (and (not (lyskom-membership-is-read))
	   (let ((membership
		  (blocking-do 'query-read-texts lyskom-pers-no conf-no)))
	     (if (and membership (lyskom-visible-membership membership))
		 (lyskom-add-membership membership conf-no))
	     membership))))


;;;; ================================================================
;;;;                   Scrolling and text insertion.


(defun lyskom-trim-buffer ()
  "Trim the size of a lyskom buffer to lyskom-max-buffer-size"
  (save-excursion
    (if (and kom-max-buffer-size
	     (> (buffer-size) kom-max-buffer-size))
	(let ((delchars (- (buffer-size) kom-max-buffer-size))
	      (inhibit-read-only t))
	  (goto-char (point-min))
	  (while (< (point) delchars)
	    (forward-line 1))
	  (delete-region (point-min) (point))))))

(defun lyskom-scroll ()
  "Scroll screen if necessary.
The position lyskom-last-viewed will always remain visible."
  ;; Find a window to scroll. Scroll the selected window if that shows LysKOM.
  ;; Otherwise scroll any window currently showing LysKOM.
  (let ((win
	 (cond
	  ((eq (window-buffer (selected-window)) (current-buffer))
	   (selected-window))
	  (t				;(get-buffer-window (current-buffer))
	   nil))))
    (if (and win			;Do nothing if no window showed LysKOM.
	     (not (pos-visible-in-window-p (point-max))))
	(progn
	  (goto-char (point-max))
	  (recenter -1)
	  (if (not (pos-visible-in-window-p lyskom-last-viewed))
	      (progn
		(set-window-start win lyskom-last-viewed)
		(move-to-window-line -1)
		(vertical-motion 1)
		(if (not (pos-visible-in-window-p))
		    (forward-char -1))))))))
	

(defun lyskom-insert (string)
  "Insert STRING last in current buffer.
Leaves the point at the end of the buffer if possible without
scrolling past lyskom-last-viewed (generally the most recent prompt.)
Leaves the point at the end of the window if not possible. If buffer
is not on screen then doesn't move point.
The text is converted according to the value of kom-emacs-knows-iso-8859-1."
  (let ((was-at-max (= (save-excursion (end-of-line) (point)) (point-max))))
    (save-excursion
      (goto-char (point-max))
      (let ((inhibit-read-only t))
	(insert string))
      (lyskom-trim-buffer))
    (let ((window (get-buffer-window (current-buffer))))
      (if (and window was-at-max)
	  (if (pos-visible-in-window-p (point-max) window)
	      (goto-char (point-max))
	    (and kom-continuous-scrolling (lyskom-scroll)))))))


(defun lyskom-insert-at-point (string)
  "Insert STRING in the current buffer at point.
The text is converted according to the value of
kom-emacs-knows-iso-8859-1."
  (let ((buffer-read-only nil))
    (insert string))
  (lyskom-trim-buffer))  


(defun lyskom-insert-before-prompt (string)
  "Insert STRING just before the prompt of if no prompt then just buffers.
If prompt on screen then do the scroll if necessary.
The strings buffered are printed before the prompt by lyskom-update-prompt."
  ;;
  ;; This is the policy for moving point:
  ;;
  ;; old-point-max is the point-max before the text is inserted
  ;; new-point-max is the point-max after the text is inserted
  ;;
  ;; If point /= old-point-max, leave the point where it is, and don't
  ;; scroll the window.
  ;;
  ;; If point = old-point-max, set it to new-point-max, and if the
  ;; buffer is in a window, make sure that point is visible.
  ;;
  (cond
   ((and lyskom-executing-command
         (not (eq lyskom-is-waiting t)))
    ;; Don't insert the string until the current command is finished.
    (if (null lyskom-to-be-printed-before-prompt)
        (setq lyskom-to-be-printed-before-prompt (lyskom-queue-create)))
    (lyskom-queue-enter lyskom-to-be-printed-before-prompt 
                        (list string)))
   (t
    ;; For some reaseon save-excursion doesn't work as expected
    (let ((oldpoint (point-marker)))
      (goto-char (point-max))
      (beginning-of-line)
      (let ((inhibit-read-only t))
	(insert string))
      (goto-char oldpoint))
    (let ((window (get-buffer-window (current-buffer))))
      (if (and window
	       (not (pos-visible-in-window-p (point) window)))
	  ;; This mease that the prompt has been pushed off the bottom
	  (save-selected-window
	    (select-window window)
	    (recenter -1)))))))
      

(defun lyskom-message (format-string &rest args)
  "Like message, but converts iso-8859/1 texts to swascii if necessary.
Args: FORMAT-STRING &rest ARGS"
  (let ((str (apply 'format format-string args)))
    (message "%s" str)))


(defun lyskom-error (format-string &rest args)
  "Like error, but converts iso-8859/1 texts to swascii if necessary.
Args: FORMAT-STRING &rest ARGS"
  (let ((str (apply 'format format-string args)))
    (error "%s" str)))


(defun lyskom-set-last-viewed ()
  (save-excursion
    (vertical-motion 0)
    (setq lyskom-last-viewed (point))))


;;; ================================================================
;;;                  Extended string formatting

;;; Author: David Byers
;;; Original code: Inge Wallin


(defvar lyskom-format-format
  "%\\(=\\)?\\(-?[0-9]+\\)?\\(#\\([0-9]+\\)\\)?\\(:\\)?\\([][@MmPpnrtsdoxc]\\)"
  "regexp matching format string parts.")

(defun lyskom-insert-string (atom)
 "Find the string corresponding to ATOM and insert it into the LysKOM buffer." 
  (lyskom-insert (lyskom-get-string atom)))

;;(defun lyskom-get-string (atom &optional assoc-list)
;;  "Get the string corresponding to ATOM and return it."
;;  (if (stringp atom)
;;	atom
;;    (let ((format-pair (assoc atom (or assoc-list lyskom-strings))))
;;	(if (null format-pair)
;;	    (signal 'lyskom-internal-error 
;;		    (list 'lyskom-get-string
;;			  (list atom ": string not found")))
;;	  (cdr format-pair)))))


(defun lyskom-format (format-string &rest argl)
  (format-state->result (lyskom-do-format format-string argl)))

(defun lyskom-format-insert (format-string &rest argl)
  "Format and insert a string according to FORMAT-STRING.
The string is inserted at the end of the buffer with `lyskom-insert'."
  (let* ((state (lyskom-do-format format-string argl t))
	 ;; We have to use a marker, because lyskom-insert may trim
	 ;; the buffer size.
	 (start (point-max-marker))
	 (deferred (format-state->delayed-content state)))
    (lyskom-insert (format-state->result state))
    (while deferred
      (let ((defer-info (car deferred))
	    (m (make-marker)))
	(set-marker m (+ start (defer-info->pos defer-info)))
	(set-defer-info->pos defer-info m)			     
	(lyskom-defer-insertion defer-info)
	(setq deferred (cdr deferred))))
    (set-marker start nil)))

(defun lyskom-format-insert-at-point (format-string &rest argl)
  "Format and insert a string according to FORMAT-STRING.
The string is inserted at point."
  (let* ((state (lyskom-do-format format-string argl t))
	 (start (point))
	 (deferred (format-state->delayed-content state)))
    (lyskom-insert-at-point (format-state->result state))
    (while deferred
      (let ((defer-info (car deferred))
	    (m (make-marker)))
	(set-marker m (+ start (defer-info->pos defer-info)))
	(set-defer-info->pos defer-info m)			     
	(lyskom-defer-insertion defer-info)
	(setq deferred (cdr deferred))))))

(defun lyskom-format-insert-before-prompt (format-string &rest argl)
  "Format and insert a string according to FORMAT-STRING.
The string is inserted just before the prompt, and if the prompt is not
currently visible the text is queued to be inserted when the prompt
reappears.

Note that it is not allowed to use deferred insertions in the text."
  (lyskom-insert-before-prompt
   (format-state->result (lyskom-do-format format-string argl))))


(defun lyskom-do-format (format-string &optional argl allow-defer)
  "Do the actual formatting and return the resulting format-state."
  (let ((fmt (cond ((stringp format-string) format-string)
		   ((symbolp format-string) (lyskom-get-string 
					     format-string))))
	(state nil))
    (if (null fmt)
        (signal 'lyskom-internal-error (list 'lyskom-format-insert
                                             ": bad format string"))
      (save-excursion
        (if (and (boundp 'lyskom-buffer)
		 lyskom-buffer)
            (set-buffer lyskom-buffer))
	(condition-case error
	    (setq state (lyskom-format-aux (make-format-state
					    fmt
					    0
					    argl
					    "")
					   allow-defer))
	  (lyskom-format-error
	   (error "LysKOM internal error formatting %s: %s%s"
		  format-string (nth 1 error) (nth 2 error))))))
    state))





(defun lyskom-format-aux (format-state allow-defer)
  (let ((format-length (length (format-state->format-string format-state)))
        (arg-no nil)
        (pad-length nil)
        (format-letter nil)
        (colon-flag nil)
        (equals-flag nil)
        (abort-format nil))

    ;;
    ;;  Eat the format string bit by bit
    ;;

    (while (and (not abort-format)
                (< (format-state->start format-state)
                   format-length))

      ;;
      ;;    Look for a format letter. If there is none, finish up,
      ;;    otherwise handle each letter separately
      ;;

      (if (null (string-match lyskom-format-format
                              (format-state->format-string format-state)
                              (format-state->start format-state)))
          (progn
            (set-format-state->result 
             format-state
             (concat (format-state->result format-state)
                     (substring (format-state->format-string format-state)
                                (format-state->start format-state))))
            (set-format-state->start format-state
                                     (length (format-state->format-string
                                              format-state))))

        ;;
        ;; A format letter has been found
        ;;

        (set-format-state->result 
         format-state
         (concat (format-state->result format-state)
                 (substring (format-state->format-string format-state)
                            (format-state->start format-state)
                            (match-beginning 0))))

        (set-format-state->start format-state
                                 (match-end 0))

	(setq equals-flag (match-beginning 1)
	      pad-length (if (match-beginning 2)
			     (string-to-int (substring 
					     (format-state->format-string
					      format-state)
					     (match-beginning 2)
					     (match-end 2)))
			   nil)
	      arg-no (if (match-beginning 4)
			 (string-to-int (substring (format-state->format-string
						    format-state)
						   (match-beginning 4)
						   (match-end 4)))
		       nil)
	      colon-flag (match-beginning 5)
	      format-letter (if (match-beginning 6)
				(aref (format-state->format-string 
				       format-state)
				      (match-beginning 6))
			      (signal 'lyskom-internal-error
				      (list 'lyskom-format-aux 
					    (format-state->format-string
					     format-state)))))

    ;;
    ;;  If the format letter is an end-of-group letter, abort
    ;;  formatting and return to the caller.
    ;;

	(if (= ?\] format-letter)
	    (progn 
	      (setq abort-format t)
	      (set-format-state->start format-state (match-end 0)))

	  (setq format-state 
            (lyskom-format-aux-help 
             format-state
             pad-length
             arg-no
             format-letter
             equals-flag
             colon-flag
             (if (and (match-beginning 2)
                      (eq (aref (format-state->format-string format-state)
                                (match-beginning 2))
                          ?0))
                 ?0
               ? )
	     allow-defer))))))
  (lyskom-tweak-format-state format-state))


(defun lyskom-format-aux-help (format-state
                               pad-length
                               arg-no
                               format-letter
                               equals-flag
                               colon-flag
                               pad-letter
			       allow-defer)
  (let ((arg nil)
        (result nil)
        (propl nil)
        (prop-adjust-start 0)
        (prop-adjust-end 0)
        (oldpos (length (format-state->result format-state)))
        (abs-length (cond ((null pad-length) nil)
                          ((< pad-length 0) (- 0 pad-length))
                          (t pad-length))))
    (if (and arg-no 
             (< (format-state->args-length format-state) arg-no))
        (signal 'lyskom-format-error (list 'lyskom-format
                                             ": too few arguments")))
    (if arg-no
        (setq arg (nth (1- arg-no) (format-state->args format-state))))
    
    (if (format-props-p arg)        
        (setq propl (format-props->propl arg)
              arg (format-props->arg arg)))
    
    
    (cond
     ;;
     ;;  Format a string or symbol by simply inserting it into the
     ;;  result list
     ;;
     ((= format-letter ?s)
      (setq result (cond ((stringp arg) arg)
                         ((symbolp arg) (symbol-name arg))
                         (t (signal 'lyskom-format-error
                                    (list 'lyskom-format
                                          ": argument error"))))))
     ;;
     ;;  Format a number by conferting it to a string and inserting
     ;;  it into the result list
     ;;
     ((or (= format-letter ?d)
          (= format-letter ?o)
          (= format-letter ?x))
      (setq result (if (integerp arg)
                       (format (format "%%%c" format-letter)
                               arg)
                     (signal 'lyskom-internal-error
                             (list 'lyskom-format
                                   ": argument error")))))
     ;;
     ;;  Format a character by converting it to a string and inserting
     ;;  it into the result list
     ;;
     ((= format-letter ?c)
      (setq result (if (integerp arg)
                       (char-to-string arg)
                     (signal 'lyskom-internal-error
                             (list 'lyskom-format
                                   ": argument error")))))
     ;;
     ;;  Format a literal percent character by inserting a string
     ;;  containing it into the result list
     ;;
     ((= format-letter ?%)
      (setq result "%")) 
     
     ;;
     ;;  Format a command name somewhat specially
     ;;
     ((= format-letter ?C)
      (setq result (cond ((stringp arg) arg)
                         ((vectorp arg) 
                          (mapconcat 'single-key-description
                                     (append arg nil) " "))
                         ((symbolp arg)
                          (if (memq arg lyskom-commands)
			      (lyskom-get-string arg)
			    (princ arg)))
                         (t (format "%S" arg)))))

     ;;
     ;;  Format a sexp by princing it. Sort of.
     ;;
     ((= format-letter ?S)
      (setq result (format "%S" arg)))

     ;;
     ;;  Format a text property array indicator by retreiving the
     ;;  properties from the argument list and adding a start of 
     ;;  new properties to the format state
     ;;
     ((= format-letter ?@)
      (set-format-state->delayed-propl
       format-state
       (cons (cons (length (format-state->result format-state))
                   arg)
             (format-state->delayed-propl format-state))))
     ;;
     ;;  Format a subformat list by recursively formatting the contents
     ;;  of the list, augmenting the result and format state
     ;;
     ;;  Idea: If this code used lyskom-do-format instead, we could
     ;;  use it to truncate a complex format by using a format string
     ;;  such as:  "%17[ %#1s will be truncated %]"
     ;;
     ;;  This could be useful for faster response when deferring
     ;;  printing. But this function would become more complex and
     ;;  slower.
     ;;
     ((= format-letter ?\[)
      (setq format-state (lyskom-format-aux format-state allow-defer)
            result nil))
     ;;
     ;;  Format a conference or person name by retreiving information
     ;;  about the conference or person and inserting it as a button
     ;;  (unless the colon flag is set)
     ;;
     ((or (= format-letter ?M)
          (= format-letter ?P))
      (setq result
            (cond
             ;; The string is already supplied
             ((stringp arg) arg)

             ;; Conference 0 does not exist, and person 0 means anonymous
             ((and (integerp arg)
                   (zerop arg))
	      (setq colon-flag t)
              (lyskom-format (cond (lyskom-default-conf-string
				    lyskom-default-conf-string)
				   ((= format-letter ?P) 'person-is-anonymous)
				   (t 'conference-does-not-exist))
			     arg)
	      )

             ;; Delay the printing
             ((and allow-defer
                   kom-deferred-printing
                   (integerp arg))
              (let ((tmp (cache-get-conf-stat arg)))
                (if (null tmp)
                    (let* ((format-element
			    (concat "%#2@%"
				    (if equals-flag "=" "")
				    (if pad-length (int-to-string pad-length))
				    "#1"
				    (if colon-flag ":" "")
				    (char-to-string format-letter)))
			   (defer-info (lyskom-create-defer-info
					'get-conf-stat
					arg
					'lyskom-deferred-insert-conf
					oldpos
					(if pad-length
					    (if equals-flag
						(abs pad-length)
					      (max (length
						    lyskom-defer-indicator)
						   (abs pad-length)))
					  (length lyskom-defer-indicator))
					format-element
					lyskom-default-conf-string)))
		      (set-format-state->delayed-content
                       format-state
                       (cons defer-info
                             (format-state->delayed-content
                              format-state)))
                      lyskom-defer-indicator)
                  (setq arg tmp)
                  (conf-stat->name arg))))
	     
             ;; Find the name and return it
             ((integerp arg)
              (let ((conf-stat (blocking-do 'get-conf-stat arg)))
                (if (null conf-stat)
                    (lyskom-format (if (= format-letter ?P)
                                       'person-does-not-exist
                                     'conference-does-not-exist)
                                   arg)
                  (conf-stat->name conf-stat))))
	     
             ;; We got a conf-stat, and can use it directly
             ((lyskom-conf-stat-p arg) (conf-stat->name arg))

             ;; Something went wrong
             (t (signal 'lyskom-internal-error
                        (list 'lyskom-format
                              ": argument error")))))
      (if (and (not colon-flag)
               (or (lyskom-conf-stat-p arg)
                   (numberp arg)))
          (setq propl 
                (append
                 (lyskom-default-button (if (= format-letter ?P) 'pers 'conf)
                                        arg)
                 propl))))
     ;;
     ;;  Format a conference or person number the same way as names,
     ;;  but insert the number rather than the name
     ;;
     ((or (= format-letter ?m)
          (= format-letter ?p))
      (setq result
            (cond ((integerp arg) 
		   (int-to-string arg))
                  ((lyskom-conf-stat-p arg) 
                   (int-to-string (conf-stat->conf-no arg)))
                  (t (signal 'lyskom-internal-error
                             (list 'lyskom-format
                                   ": argument error")))))
      (if (not colon-flag)
          (setq propl 
                (append 
                 (lyskom-default-button (if (= format-letter ?p) 'pers 'conf)
                                        arg)
                 propl))))
     ;;
     ;;  Format an integer or text-stat as a text number by adding the
     ;;  by inserting a button (unless the colon flag is set)
     ;;
     ((= format-letter ?n)
      (setq result
            (cond ((integerp arg) (int-to-string arg))
                  ((lyskom-text-stat-p arg) (int-to-string
                                             (text-stat->text-no arg)))
                  (t (signal 'lyskom-internal-error
                             (list 'lyskom-format
                                   ": argument error")))))
      (if (not colon-flag)
          (setq propl
                (append (lyskom-default-button 'text arg) propl))))
     ;;
     ;;  Format a subject line by adding the subject face to the text
     ;;  properties and the subject to the result list
     ;;
     ((= format-letter ?r)
      (setq result (cond ((stringp arg) (lyskom-button-transform-text arg))
                         (t (signal 'lyskom-internal-error
                                    (list 'lyskom-format
                                          ": argument error")))))
      (if (and (not colon-flag)
               (not (lyskom-face-default-p 'kom-subject-face)))
          (setq propl (append (list 'face 'kom-subject-face) propl))))
     ;;
     ;;  Format a LysKOM text body. Currently this does nothing. It
     ;;  should parse the text for buttons
     ;;
     ((= format-letter ?t)

      ;; +++ One would want to do this before or after, but then
      ;; buttons will not be visible and other highlighting will
      ;; disappear.

      ;; (if (not colon-flag)
      ;;     (setq propl (append (list 'face 'kom-text-face) propl)))

      (setq result
            (cond ((stringp arg) (lyskom-format-text-body arg))
                  ((lyskom-text-p arg) 
                   (lyskom-format-text-body (text->text-mass arg)))
                  (t (signal 'lyskom-internal-error
                             (list 'lyskom-format
                                   ": argument error"))))))


     ;;
     ;; Insert some deferred text
     ;;
     ((= format-letter ?D)
      (setq result
	    (cond
	     ((stringp arg) arg)
	     (t
	      (let ((format-element
		     (concat "%"
			     (if equals-flag "=" "")
			     (if pad-length (int-to-string pad-length))
			     "#1"
			     (if colon-flag ":" "")
			     "s")))
		(set-defer-info->pos arg oldpos)
		(set-defer-info->del-chars
		 arg (if pad-length
			 (if equals-flag
			     (abs pad-length)
			   (max (length
				 lyskom-defer-indicator)
				(abs pad-length)))
		       (length lyskom-defer-indicator)))
		(set-defer-info->format arg format-element))
	      (set-format-state->delayed-content
	       format-state
	       (cons arg
		     (format-state->delayed-content
		      format-state)))
	      lyskom-defer-indicator))))

     ;;
     ;; The format letter was unknown
     ;;
     
     (t (signal 'lyskom-internal-error
		(list 'lyskom-format-help format-letter))))
    
    ;;
    ;; Pad the result to the appropriate length
    ;; Fix flags so text props go in the right places anyway
    ;;
    
    (cond ((or (null pad-length)
               (null result)) nil)
          ((> abs-length (length result))
           (let ((padstring (make-string (- abs-length (length result))
                                         pad-letter)))
             (if (< pad-length 0)       ; LEFT justify
                 (progn
                   (setq prop-adjust-end (- (- abs-length (length result))))
                   (setq result (concat result padstring)))
               (progn
                 (setq prop-adjust-start (- abs-length (length result)))
                 (setq result (concat padstring result))))))
          ((and equals-flag
                (< abs-length (length result)))
           (setq result (substring result 0 abs-length))))
    
    (if result
        (progn
          (set-format-state->result 
           format-state
           (concat (format-state->result format-state)
                   result))))
    (if (and propl kom-text-properties)
        (add-text-properties
         (+ oldpos prop-adjust-start)
         (+ (length (format-state->result format-state)) prop-adjust-end)
         propl
         (format-state->result format-state))))
  format-state)




(defun lyskom-tweak-format-state (format-state) 
  (let ((dp (format-state->delayed-propl format-state)))
    (while dp
      (add-text-properties (car (car dp))
                           (length (format-state->result format-state))
                           (cdr (car dp))
                           (format-state->result format-state))
      (setq dp (cdr dp)))
    (set-format-state->delayed-propl format-state nil))
  format-state)


;;; ================================================================
;;;			 Text body formatting

;;; Author: David K}gedal
;;; This should be considered an experiment

(defvar lyskom-format-experimental nil)

(lyskom-external-function w3-fetch)
(lyskom-external-function w3-preview-this-buffer)

(defun lyskom-format-text-body (text)
  "Format a text for insertion. Does parsing of special markers in the text."
  ;; This function is probably not written as it should
  (if lyskom-format-experimental
      (cond
       ((and (string-match "\\`html:" text)
             (condition-case e (require 'w3) (error nil)))
        (let ((tmpbuf (generate-new-buffer "lyskom-html")))
          (unwind-protect
              (save-excursion
                (set-buffer tmpbuf)
                (insert (substring text 5))
                (w3-preview-this-buffer))
            (kill-buffer tmpbuf))))
       ((and (fboundp 'format-decode-buffer)
             (string-match "\\`enriched:" text))
        (let ((tmpbuf (generate-new-buffer "lyskom-enriched")))
          (unwind-protect
              (save-excursion
                (set-buffer tmpbuf)
                (insert (substring text 10))
                (format-decode-buffer)
                (lyskom-button-transform-text (buffer-string))
                ;; (substring (buffer-string) 0 -1) ; Remove the \n
                )
            (kill-buffer tmpbuf))))
       (t (lyskom-button-transform-text text)
	))
    (if kom-text-properties
	(lyskom-button-transform-text text)
      text)))
    


;;; ============================================================
;;;                     Beeping and feeping
;;;                     Faces and colors
;;;

(defun lyskom-beep (arg)
  "Beep. ARG is how to beep. 
nil means don't beep.
t means beep once.
A number means beep that number of times (.1 second delay between beeps).
A string means start the command kom-audio-player with the string as argument.
A symbol other than t means call it as a function."
  (cond ((null arg))
        ((eq t arg) (ding t))
        ((numberp arg) (while (> arg 0)
                         (ding t)
                         (sit-for 0.1)
                         (setq arg (1- arg))))
        ((stringp arg)
         (start-process "audio"
                        nil
                        kom-audio-player
                        arg))
        ((and (symbolp arg)
              (fboundp arg))
         (condition-case nil
             (funcall arg)
           (error (message "Error in beep function")
                  (beep))))
        (t (beep))))

(defun lyskom-face-default-p (f1)
  "Return t if f1 is undefined or the default face."
  (or (not (facep f1))
      (face-equal f1 'default)))
		  

;;;; ================================================================
;;;;                         Running in buffer 

;;; Author: Linus


(defun backward-text (&optional arg)
  "Searches backwards for a text start and recenters with that text at the top."
  (interactive "p")
  (let ((paragraph-start lyskom-text-start))
    (backward-paragraph arg))
  (beginning-of-line))


(defun forward-text (&optional arg)
  "Searches forward for a text start and recenters with that text at the top."
  (interactive "p")
  (let ((paragraph-start lyskom-text-start))
    (forward-paragraph arg)))


(defun kom-save-text (&optional arg)
  "Saves/appends the article before point to a file.
The article is determined by a search-backward the same as backward-text 
and then a forward-text.
With an argument ARG the search is done over that number of texts.
The name of the file is read using the minibuffer and the default is kom-text."
  (interactive "p")
  (save-excursion
    (backward-text arg)
    (let ((p1 (point))
	  (p2 (progn
		(forward-text arg)
		(beginning-of-line)
		(point)))
	  (name (read-file-name
		 (lyskom-format 'save-on-file-q
				    (file-name-nondirectory
				     lyskom-saved-file-name))
		 (file-name-directory lyskom-saved-file-name)
		 lyskom-saved-file-name
		 nil)))
      (if (file-directory-p name)
	  (setq name (concat (file-name-as-directory name)
			     (file-name-nondirectory lyskom-saved-file-name))))
      (append-to-file p1 p2
		      (expand-file-name name))
      (setq lyskom-saved-file-name name))))


;;; ================================================================
;;;                Some useful abstractions

(defsubst lyskom-membership-highest-index ()
  "Return the number of conferences the user is a member of minus 1.
This is the highest index in lyskom-membership that contains data, if
positions are counted from 0, as they are."
  (1- (length lyskom-membership)))


;;; ================================================================
;;;                             To-do


(defun lyskom-update-prompt ()
  "Print prompt if the client knows which command will be default.
Set lyskom-current-prompt accordingly. Tell server what I am doing."
  (if (or lyskom-executing-command
	  (and lyskom-current-prompt
	       lyskom-dont-change-prompt))
      nil
    (let ((to-do (lyskom-what-to-do))
	  (prompt nil))
      (setq lyskom-command-to-do to-do)
      (cond
     
       ((eq to-do 'next-pri-conf)
	(setq prompt 'go-to-pri-conf-prompt)
	(or (eq lyskom-current-prompt prompt)
	    (lyskom-beep kom-ding-on-priority-break)))

       ((eq to-do 'next-pri-text)
	(setq prompt 'read-pri-text-conf)
	(or (eq lyskom-current-prompt promp