[config.git] / djavu-asus / elpa / jabber-20230715.456 / jabber-rtt.el

;;; jabber-rtt.el --- XEP-0301: In-Band Real Time Text  -*- lexical-binding: t; -*-

;; Copyright (C) 2013  Magnus Henoch

;; Author: Magnus Henoch <magnus.henoch@gmail.com>

;; This program 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 3 of the License, or
;; (at your option) any later version.

;; This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:

;;

;;; Code:

(eval-when-compile (require 'cl-lib))

;;;; Handling incoming events

;;;###autoload
(eval-after-load "jabber-disco"
  '(jabber-disco-advertise-feature "urn:xmpp:rtt:0"))

(defvar jabber-rtt-ewoc-node nil)
(make-variable-buffer-local 'jabber-rtt-ewoc-node)

(defvar jabber-rtt-last-seq nil)
(make-variable-buffer-local 'jabber-rtt-last-seq)

(defvar jabber-rtt-message nil)
(make-variable-buffer-local 'jabber-rtt-message)

(defvar jabber-rtt-pending-events nil)
(make-variable-buffer-local 'jabber-rtt-pending-events)

(defvar jabber-rtt-timer nil)
(make-variable-buffer-local 'jabber-rtt-timer)

;; Add function last in chain, so a chat buffer is already created.
;;;###autoload
(eval-after-load "jabber-core"
  '(add-to-list 'jabber-message-chain #'jabber-rtt-handle-message t))

;;;###autoload
(defun jabber-rtt-handle-message (jc xml-data)
  ;; We could support this for MUC as well, if useful.
  (when (and (not (jabber-muc-message-p xml-data))
	     (get-buffer (jabber-chat-get-buffer (jabber-xml-get-attribute xml-data 'from))))
    (with-current-buffer (jabber-chat-get-buffer (jabber-xml-get-attribute xml-data 'from))
      (let* ((rtt (jabber-xml-path xml-data '(("urn:xmpp:rtt:0" . "rtt"))))
	     (body (jabber-xml-path xml-data '(body)))
	     (seq (when rtt (jabber-xml-get-attribute rtt 'seq)))
	     (event (when rtt (or (jabber-xml-get-attribute rtt 'event) "edit")))
	     (actions (when rtt (jabber-xml-node-children rtt)))
	     (inhibit-read-only t))
	(cond
	 ((or body (string= event "cancel"))
	  ;; A <body/> element supersedes real time text.
	  (jabber-rtt--reset))
	 ((member event '("new" "reset"))
	  (jabber-rtt--reset)
	  (setq jabber-rtt-ewoc-node
		(ewoc-enter-last jabber-chat-ewoc (list :notice "[typing...]"))
		jabber-rtt-last-seq (string-to-number seq)
		jabber-rtt-message ""
		jabber-rtt-pending-events nil)
	  (jabber-rtt--enqueue-actions actions))
	 ((string= event "edit")
	  ;; TODO: check whether this works properly in 32-bit Emacs
	  (cond
	   ((and jabber-rtt-last-seq
		 (equal (1+ jabber-rtt-last-seq)
			(string-to-number seq)))
	    ;; We are in sync.
	    (setq jabber-rtt-last-seq (string-to-number seq))
	    (jabber-rtt--enqueue-actions actions))
	   (t
	    ;; TODO: show warning when not in sync
	    (message "out of sync! %s vs %s"
		     seq jabber-rtt-last-seq))))
	 ;; TODO: handle event="init"
	 )))))

(defun jabber-rtt--reset ()
  (when jabber-rtt-ewoc-node
    (ewoc-delete jabber-chat-ewoc jabber-rtt-ewoc-node))
  (when (timerp jabber-rtt-timer)
    (cancel-timer jabber-rtt-timer))
  (setq jabber-rtt-ewoc-node nil
	jabber-rtt-last-seq nil
	jabber-rtt-message nil
	jabber-rtt-pending-events nil
	jabber-rtt-timer nil))

(defun jabber-rtt--enqueue-actions (new-actions)
  (setq jabber-rtt-pending-events
	;; Ensure that the queue never contains more than 700 ms worth
	;; of wait events.
	(jabber-rtt--fix-waits (append jabber-rtt-pending-events new-actions)))
  (unless jabber-rtt-timer
    (jabber-rtt--process-actions (current-buffer))))

(defun jabber-rtt--process-actions (buffer)
  (with-current-buffer buffer
    (setq jabber-rtt-timer nil)
    (catch 'wait
      (while jabber-rtt-pending-events
	(let ((action (pop jabber-rtt-pending-events)))
	  (cl-case (jabber-xml-node-name action)
	    ((t)
	     ;; insert text
	     (let* ((p (jabber-xml-get-attribute action 'p))
		    (position (if p (string-to-number p) (length jabber-rtt-message))))
	       (setq position (max position 0))
	       (setq position (min position (length jabber-rtt-message)))
	       (setf (substring jabber-rtt-message position position)
		     (car (jabber-xml-node-children action)))

	       (ewoc-set-data jabber-rtt-ewoc-node (list :notice (concat "[typing...] " jabber-rtt-message)))
	       (let ((inhibit-read-only t))
		 (ewoc-invalidate jabber-chat-ewoc jabber-rtt-ewoc-node))))
	    ((e)
	     ;; erase text
	     (let* ((p (jabber-xml-get-attribute action 'p))
		    (position (if p (string-to-number p) (length jabber-rtt-message)))
		    (n (jabber-xml-get-attribute action 'n))
		    (number (if n (string-to-number n) 1)))
	       (setq position (max position 0))
	       (setq position (min position (length jabber-rtt-message)))
	       (setq number (max number 0))
	       (setq number (min number position))
	       ;; Now erase the NUMBER characters before POSITION.
	       (setf (substring jabber-rtt-message (- position number) position)
		     "")

	       (ewoc-set-data jabber-rtt-ewoc-node (list :notice (concat "[typing...] " jabber-rtt-message)))
	       (let ((inhibit-read-only t))
		 (ewoc-invalidate jabber-chat-ewoc jabber-rtt-ewoc-node))))
	    ((w)
	     (setq jabber-rtt-timer
		   (run-with-timer
		    (/ (string-to-number (jabber-xml-get-attribute action 'n)) 1000.0)
		    nil
		    #'jabber-rtt--process-actions
		    buffer))
	     (throw 'wait nil))))))))

(defun jabber-rtt--fix-waits (actions)
  ;; Ensure that the sum of all wait events is no more than 700 ms.
  (let ((sum 0))
    (dolist (action actions)
      (when (eq (jabber-xml-node-name action) 'w)
	(let ((n (jabber-xml-get-attribute action 'n)))
	  (setq n (string-to-number n))
	  (when (>= n 0)
	    (setq sum (+ sum n))))))

    (if (<= sum 700)
	actions
      (let ((scale (/ 700.0 sum)))
	(mapcar
	 (lambda (action)
	   (if (eq (jabber-xml-node-name action) 'w)
	       (let ((n (jabber-xml-get-attribute action 'n)))
		 (setq n (string-to-number n))
		 (setq n (max n 0))
		 `(w ((n . ,(number-to-string (* scale n)))) nil))
	     action))
	 actions)))))

;;;; Sending events

(defvar jabber-rtt-send-timer nil)
(make-variable-buffer-local 'jabber-rtt-send-timer)

(defvar jabber-rtt-send-seq nil)
(make-variable-buffer-local 'jabber-rtt-send-seq)

(defvar jabber-rtt-outgoing-events nil)
(make-variable-buffer-local 'jabber-rtt-outgoing-events)

(defvar jabber-rtt-send-last-timestamp nil)
(make-variable-buffer-local 'jabber-rtt-send-last-timestamp)

;;;###autoload
(define-minor-mode jabber-rtt-send-mode
  "Show text to recipient as it is being typed.
This lets the recipient see every change made to the message up
until it's sent.  The recipient's client needs to implement
XEP-0301, In-Band Real Time Text."
  nil " Real-Time" nil
  (if (null jabber-rtt-send-mode)
      (progn
	(remove-hook 'after-change-functions #'jabber-rtt--queue-update t)
	(remove-hook 'jabber-chat-send-hooks #'jabber-rtt--message-sent t)
	(jabber-rtt--cancel-send))
    (unless (derived-mode-p 'jabber-chat-mode)
      (error "Real Time Text only makes sense in chat buffers"))
    (when (timerp jabber-rtt-send-timer)
      (cancel-timer jabber-rtt-send-timer))
    (setq jabber-rtt-send-timer nil
	  jabber-rtt-send-seq nil
	  jabber-rtt-outgoing-events nil
	  jabber-rtt-send-last-timestamp nil)
    (jabber-rtt--send-current-text nil)
    (add-hook 'after-change-functions #'jabber-rtt--queue-update nil t)
    (add-hook 'jabber-chat-send-hooks #'jabber-rtt--message-sent nil t)))

(defun jabber-rtt--cancel-send ()
  (when (timerp jabber-rtt-send-timer)
    (cancel-timer jabber-rtt-send-timer))
  (setq jabber-rtt-send-seq (1+ jabber-rtt-send-seq))
  (jabber-send-sexp jabber-buffer-connection
		    `(message ((to . ,jabber-chatting-with)
			       (type . "chat"))
			      (rtt ((xmlns . "urn:xmpp:rtt:0")
				    (seq . ,(number-to-string jabber-rtt-send-seq))
				    (event . "cancel"))
				   nil)))
  (setq jabber-rtt-send-timer nil
	jabber-rtt-send-seq nil
	jabber-rtt-outgoing-events nil
	jabber-rtt-send-last-timestamp nil))

(defun jabber-rtt--send-current-text (resetp)
  (let ((text (buffer-substring-no-properties jabber-point-insert (point-max))))
    ;; This should give us enough room to avoid wrap-arounds, even
    ;; with just 28 bits...
    (setq jabber-rtt-send-seq (random 100000))
    (jabber-send-sexp jabber-buffer-connection
		      `(message ((to . ,jabber-chatting-with)
				 (type . "chat"))
				(rtt ((xmlns . "urn:xmpp:rtt:0")
				      (seq . ,(number-to-string jabber-rtt-send-seq))
				      (event . ,(if resetp "reset" "new")))
				     (t () ,text))))))

(defun jabber-rtt--queue-update (beg end pre-change-length)
  (unless (or (< beg jabber-point-insert)
	      (< end jabber-point-insert))
    (let ((timestamp (current-time)))
      (when jabber-rtt-send-last-timestamp
	(let* ((time-difference (time-subtract timestamp jabber-rtt-send-last-timestamp))
	       (interval (truncate (* 1000 (float-time time-difference)))))
	  (when (and (> interval 0)
		     ;; Don't send too long intervals - this should have
		     ;; been sent by our timer already.
		     (< interval 1000))
	    (push `(w ((n . ,(number-to-string interval))) nil)
		  jabber-rtt-outgoing-events))))
      (setq jabber-rtt-send-last-timestamp timestamp))

    (when (> pre-change-length 0)
      ;; Some text was deleted.  Let's check if we can use a shorter
      ;; tag:
      (let ((at-end (= end (point-max)))
	    (erase-one (= pre-change-length 1)))
	(push `(e (
		   ,@(unless at-end
		       `((p . ,(number-to-string
				(+ beg
				   (- jabber-point-insert)
				   pre-change-length)))))
		   ,@(unless erase-one
		       `((n . ,(number-to-string pre-change-length))))))
	      jabber-rtt-outgoing-events)))

    (when (/= beg end)
      ;; Some text was inserted.
      (let ((text (buffer-substring-no-properties beg end))
	    (at-end (= end (point-max))))
	(push `(t (
		   ,@(unless at-end
		       `((p . ,(number-to-string (- beg jabber-point-insert))))))
		  ,text)
	      jabber-rtt-outgoing-events)))

    (when (null jabber-rtt-send-timer)
      (setq jabber-rtt-send-timer
	    (run-with-timer 0.7 nil #'jabber-rtt--send-queued-events (current-buffer))))))

(defun jabber-rtt--send-queued-events (buffer)
  (with-current-buffer buffer
    (setq jabber-rtt-send-timer nil)
    (when jabber-rtt-outgoing-events
      (let ((event (if jabber-rtt-send-seq "edit" "new")))
	(setq jabber-rtt-send-seq
	      (if jabber-rtt-send-seq
		  (1+ jabber-rtt-send-seq)
		(random 100000)))
	(jabber-send-sexp jabber-buffer-connection
			  `(message ((to . ,jabber-chatting-with)
				     (type . "chat"))
				    (rtt ((xmlns . "urn:xmpp:rtt:0")
					  (seq . ,(number-to-string jabber-rtt-send-seq))
					  (event . ,event))
					 ,@(nreverse jabber-rtt-outgoing-events))))
	(setq jabber-rtt-outgoing-events nil)))))

(defun jabber-rtt--message-sent (_text _id)
  ;; We're sending a <body/> element; reset our state
  (when (timerp jabber-rtt-send-timer)
    (cancel-timer jabber-rtt-send-timer))
  (setq jabber-rtt-send-timer nil
	jabber-rtt-send-seq nil
	jabber-rtt-outgoing-events nil
	jabber-rtt-send-last-timestamp nil))

(provide 'jabber-rtt)
;;; jabber-rtt.el ends here
Commit	Line	Data
53e6db90 DC	1	;;; jabber-rtt.el --- XEP-0301: In-Band Real Time Text -- lexical-binding: t; --
	2
	3	;; Copyright (C) 2013 Magnus Henoch
	4
	5	;; Author: Magnus Henoch <magnus.henoch@gmail.com>
	6
	7	;; This program is free software; you can redistribute it and/or modify
	8	;; it under the terms of the GNU General Public License as published by
	9	;; the Free Software Foundation, either version 3 of the License, or
	10	;; (at your option) any later version.
	11
	12	;; This program is distributed in the hope that it will be useful,
	13	;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	;; GNU General Public License for more details.
	16
	17	;; You should have received a copy of the GNU General Public License
	18	;; along with this program. If not, see <http://www.gnu.org/licenses/>.
	19
	20	;;; Commentary:
	21
	22	;;
	23
	24	;;; Code:
	25
	26	(eval-when-compile (require 'cl-lib))
	27
	28	;;;; Handling incoming events
	29
	30	;;;###autoload
	31	(eval-after-load "jabber-disco"
	32	'(jabber-disco-advertise-feature "urn:xmpp:rtt:0"))
	33
	34	(defvar jabber-rtt-ewoc-node nil)
	35	(make-variable-buffer-local 'jabber-rtt-ewoc-node)
	36
	37	(defvar jabber-rtt-last-seq nil)
	38	(make-variable-buffer-local 'jabber-rtt-last-seq)
	39
	40	(defvar jabber-rtt-message nil)
	41	(make-variable-buffer-local 'jabber-rtt-message)
	42
	43	(defvar jabber-rtt-pending-events nil)
	44	(make-variable-buffer-local 'jabber-rtt-pending-events)
	45
	46	(defvar jabber-rtt-timer nil)
	47	(make-variable-buffer-local 'jabber-rtt-timer)
	48
	49	;; Add function last in chain, so a chat buffer is already created.
	50	;;;###autoload
	51	(eval-after-load "jabber-core"
	52	'(add-to-list 'jabber-message-chain #'jabber-rtt-handle-message t))
	53
	54	;;;###autoload
	55	(defun jabber-rtt-handle-message (jc xml-data)
	56	;; We could support this for MUC as well, if useful.
	57	(when (and (not (jabber-muc-message-p xml-data))
	58	(get-buffer (jabber-chat-get-buffer (jabber-xml-get-attribute xml-data 'from))))
	59	(with-current-buffer (jabber-chat-get-buffer (jabber-xml-get-attribute xml-data 'from))
	60	(let* ((rtt (jabber-xml-path xml-data '(("urn:xmpp:rtt:0" . "rtt"))))
	61	(body (jabber-xml-path xml-data '(body)))
	62	(seq (when rtt (jabber-xml-get-attribute rtt 'seq)))
	63	(event (when rtt (or (jabber-xml-get-attribute rtt 'event) "edit")))
	64	(actions (when rtt (jabber-xml-node-children rtt)))
65	(inhibit-read-only t))
66	(cond
67	((or body (string= event "cancel"))
68	;; A <body/> element supersedes real time text.
69	(jabber-rtt--reset))
70	((member event '("new" "reset"))
71	(jabber-rtt--reset)
72	(setq jabber-rtt-ewoc-node
73	(ewoc-enter-last jabber-chat-ewoc (list :notice "[typing...]"))
74	jabber-rtt-last-seq (string-to-number seq)
75	jabber-rtt-message ""
76	jabber-rtt-pending-events nil)
77	(jabber-rtt--enqueue-actions actions))
78	((string= event "edit")
79	;; TODO: check whether this works properly in 32-bit Emacs
80	(cond
81	((and jabber-rtt-last-seq
82	(equal (1+ jabber-rtt-last-seq)
83	(string-to-number seq)))
84	;; We are in sync.
85	(setq jabber-rtt-last-seq (string-to-number seq))
86	(jabber-rtt--enqueue-actions actions))
87	(t
88	;; TODO: show warning when not in sync
89	(message "out of sync! %s vs %s"
90	seq jabber-rtt-last-seq))))
91	;; TODO: handle event="init"
92	)))))
93
94	(defun jabber-rtt--reset ()
95	(when jabber-rtt-ewoc-node
96	(ewoc-delete jabber-chat-ewoc jabber-rtt-ewoc-node))
97	(when (timerp jabber-rtt-timer)
98	(cancel-timer jabber-rtt-timer))
99	(setq jabber-rtt-ewoc-node nil
100	jabber-rtt-last-seq nil
101	jabber-rtt-message nil
102	jabber-rtt-pending-events nil
103	jabber-rtt-timer nil))
104
105	(defun jabber-rtt--enqueue-actions (new-actions)
106	(setq jabber-rtt-pending-events
107	;; Ensure that the queue never contains more than 700 ms worth
108	;; of wait events.
109	(jabber-rtt--fix-waits (append jabber-rtt-pending-events new-actions)))
110	(unless jabber-rtt-timer
111	(jabber-rtt--process-actions (current-buffer))))
112
113	(defun jabber-rtt--process-actions (buffer)
114	(with-current-buffer buffer
115	(setq jabber-rtt-timer nil)
116	(catch 'wait
117	(while jabber-rtt-pending-events
118	(let ((action (pop jabber-rtt-pending-events)))
119	(cl-case (jabber-xml-node-name action)
120	((t)
121	;; insert text
122	(let* ((p (jabber-xml-get-attribute action 'p))
123	(position (if p (string-to-number p) (length jabber-rtt-message))))
124	(setq position (max position 0))
125	(setq position (min position (length jabber-rtt-message)))
126	(setf (substring jabber-rtt-message position position)
127	(car (jabber-xml-node-children action)))
128
129	(ewoc-set-data jabber-rtt-ewoc-node (list :notice (concat "[typing...] " jabber-rtt-message)))
130	(let ((inhibit-read-only t))
131	(ewoc-invalidate jabber-chat-ewoc jabber-rtt-ewoc-node))))
132	((e)
133	;; erase text
134	(let* ((p (jabber-xml-get-attribute action 'p))
135	(position (if p (string-to-number p) (length jabber-rtt-message)))
136	(n (jabber-xml-get-attribute action 'n))
137	(number (if n (string-to-number n) 1)))
138	(setq position (max position 0))
139	(setq position (min position (length jabber-rtt-message)))
140	(setq number (max number 0))
141	(setq number (min number position))
142	;; Now erase the NUMBER characters before POSITION.
143	(setf (substring jabber-rtt-message (- position number) position)
144	"")
145
146	(ewoc-set-data jabber-rtt-ewoc-node (list :notice (concat "[typing...] " jabber-rtt-message)))
147	(let ((inhibit-read-only t))
148	(ewoc-invalidate jabber-chat-ewoc jabber-rtt-ewoc-node))))
149	((w)
150	(setq jabber-rtt-timer
151	(run-with-timer
152	(/ (string-to-number (jabber-xml-get-attribute action 'n)) 1000.0)
153	nil
154	#'jabber-rtt--process-actions
155	buffer))
156	(throw 'wait nil))))))))
157
158	(defun jabber-rtt--fix-waits (actions)
159	;; Ensure that the sum of all wait events is no more than 700 ms.
160	(let ((sum 0))
161	(dolist (action actions)
162	(when (eq (jabber-xml-node-name action) 'w)
163	(let ((n (jabber-xml-get-attribute action 'n)))
164	(setq n (string-to-number n))
165	(when (>= n 0)
166	(setq sum (+ sum n))))))
167
168	(if (<= sum 700)
169	actions
170	(let ((scale (/ 700.0 sum)))
171	(mapcar
172	(lambda (action)
173	(if (eq (jabber-xml-node-name action) 'w)
174	(let ((n (jabber-xml-get-attribute action 'n)))
175	(setq n (string-to-number n))
176	(setq n (max n 0))
177	`(w ((n . ,(number-to-string (* scale n)))) nil))
178	action))
179	actions)))))
180
181	;;;; Sending events
182
183	(defvar jabber-rtt-send-timer nil)
184	(make-variable-buffer-local 'jabber-rtt-send-timer)
185
186	(defvar jabber-rtt-send-seq nil)
187	(make-variable-buffer-local 'jabber-rtt-send-seq)
188
189	(defvar jabber-rtt-outgoing-events nil)
190	(make-variable-buffer-local 'jabber-rtt-outgoing-events)
191
192	(defvar jabber-rtt-send-last-timestamp nil)
193	(make-variable-buffer-local 'jabber-rtt-send-last-timestamp)
194
195	;;;###autoload
196	(define-minor-mode jabber-rtt-send-mode
197	"Show text to recipient as it is being typed.
198	This lets the recipient see every change made to the message up
199	until it's sent. The recipient's client needs to implement
200	XEP-0301, In-Band Real Time Text."
201	nil " Real-Time" nil
202	(if (null jabber-rtt-send-mode)
203	(progn
204	(remove-hook 'after-change-functions #'jabber-rtt--queue-update t)
205	(remove-hook 'jabber-chat-send-hooks #'jabber-rtt--message-sent t)
206	(jabber-rtt--cancel-send))
207	(unless (derived-mode-p 'jabber-chat-mode)
208	(error "Real Time Text only makes sense in chat buffers"))
209	(when (timerp jabber-rtt-send-timer)
210	(cancel-timer jabber-rtt-send-timer))
211	(setq jabber-rtt-send-timer nil
212	jabber-rtt-send-seq nil
213	jabber-rtt-outgoing-events nil
214	jabber-rtt-send-last-timestamp nil)
215	(jabber-rtt--send-current-text nil)
216	(add-hook 'after-change-functions #'jabber-rtt--queue-update nil t)
217	(add-hook 'jabber-chat-send-hooks #'jabber-rtt--message-sent nil t)))
218
219	(defun jabber-rtt--cancel-send ()
220	(when (timerp jabber-rtt-send-timer)
221	(cancel-timer jabber-rtt-send-timer))
222	(setq jabber-rtt-send-seq (1+ jabber-rtt-send-seq))
223	(jabber-send-sexp jabber-buffer-connection
224	`(message ((to . ,jabber-chatting-with)
225	(type . "chat"))
226	(rtt ((xmlns . "urn:xmpp:rtt:0")
227	(seq . ,(number-to-string jabber-rtt-send-seq))
228	(event . "cancel"))
229	nil)))
230	(setq jabber-rtt-send-timer nil
231	jabber-rtt-send-seq nil
232	jabber-rtt-outgoing-events nil
233	jabber-rtt-send-last-timestamp nil))
234
235	(defun jabber-rtt--send-current-text (resetp)
236	(let ((text (buffer-substring-no-properties jabber-point-insert (point-max))))
237	;; This should give us enough room to avoid wrap-arounds, even
238	;; with just 28 bits...
239	(setq jabber-rtt-send-seq (random 100000))
240	(jabber-send-sexp jabber-buffer-connection
241	`(message ((to . ,jabber-chatting-with)
242	(type . "chat"))
243	(rtt ((xmlns . "urn:xmpp:rtt:0")
244	(seq . ,(number-to-string jabber-rtt-send-seq))
245	(event . ,(if resetp "reset" "new")))
246	(t () ,text))))))
247
248	(defun jabber-rtt--queue-update (beg end pre-change-length)
249	(unless (or (< beg jabber-point-insert)
250	(< end jabber-point-insert))
251	(let ((timestamp (current-time)))
252	(when jabber-rtt-send-last-timestamp
253	(let* ((time-difference (time-subtract timestamp jabber-rtt-send-last-timestamp))
254	(interval (truncate (* 1000 (float-time time-difference)))))
255	(when (and (> interval 0)
256	;; Don't send too long intervals - this should have
257	;; been sent by our timer already.
258	(< interval 1000))
259	(push `(w ((n . ,(number-to-string interval))) nil)
260	jabber-rtt-outgoing-events))))
261	(setq jabber-rtt-send-last-timestamp timestamp))
262
263	(when (> pre-change-length 0)
264	;; Some text was deleted. Let's check if we can use a shorter
265	;; tag:
266	(let ((at-end (= end (point-max)))
267	(erase-one (= pre-change-length 1)))
268	(push `(e (
269	,@(unless at-end
270	`((p . ,(number-to-string
271	(+ beg
272	(- jabber-point-insert)
273	pre-change-length)))))
274	,@(unless erase-one
275	`((n . ,(number-to-string pre-change-length))))))
276	jabber-rtt-outgoing-events)))
277
278	(when (/= beg end)
279	;; Some text was inserted.
280	(let ((text (buffer-substring-no-properties beg end))
281	(at-end (= end (point-max))))
282	(push `(t (
283	,@(unless at-end
284	`((p . ,(number-to-string (- beg jabber-point-insert))))))
285	,text)
286	jabber-rtt-outgoing-events)))
287
288	(when (null jabber-rtt-send-timer)
289	(setq jabber-rtt-send-timer
290	(run-with-timer 0.7 nil #'jabber-rtt--send-queued-events (current-buffer))))))
291
292	(defun jabber-rtt--send-queued-events (buffer)
293	(with-current-buffer buffer
294	(setq jabber-rtt-send-timer nil)
295	(when jabber-rtt-outgoing-events
296	(let ((event (if jabber-rtt-send-seq "edit" "new")))
297	(setq jabber-rtt-send-seq
298	(if jabber-rtt-send-seq
299	(1+ jabber-rtt-send-seq)
300	(random 100000)))
301	(jabber-send-sexp jabber-buffer-connection
302	`(message ((to . ,jabber-chatting-with)
303	(type . "chat"))
304	(rtt ((xmlns . "urn:xmpp:rtt:0")
305	(seq . ,(number-to-string jabber-rtt-send-seq))
306	(event . ,event))
307	,@(nreverse jabber-rtt-outgoing-events))))
308	(setq jabber-rtt-outgoing-events nil)))))
309
310	(defun jabber-rtt--message-sent (_text _id)
311	;; We're sending a <body/> element; reset our state
312	(when (timerp jabber-rtt-send-timer)
313	(cancel-timer jabber-rtt-send-timer))
314	(setq jabber-rtt-send-timer nil
315	jabber-rtt-send-seq nil
316	jabber-rtt-outgoing-events nil
317	jabber-rtt-send-last-timestamp nil))
318
319	(provide 'jabber-rtt)
320	;;; jabber-rtt.el ends here