;;; talk.el --- Allow several users to talk to each other through Emacs.
;; Copyright (C) 1995 Free Software Foundation, Inc.
;; Keywords: comm, frames
;; This file is part of GNU Emacs.
;; GNU Emacs 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.
;; GNU Emacs 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 GNU Emacs; see the file COPYING. If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.
;; This is a multi-user talk package that runs in Emacs.
;; Use talk-connect to bring a new person into the conversation.
(defvar talk-display-alist nil
"Alist of displays on which Emacs talk is now running.
Each element has the form (DISPLAY FRAME BUFFER).")
(defun talk-connect (display)
"Connect to display DISPLAY for the Emacs talk group."
(interactive "sTalk to display: ")
;; Make sure we have an entry for the current display.
(let ((mydisp (cdr (assq 'display (frame-parameters (selected-frame))))))
;; Make sure we have an entry for the specified display.
;; Add the new buffers to all talk frames.
(defun talk-add-display (display)
(let* ((elt (assoc display talk-display-alist))
(name (concat "*talk-" display "*"))
(if (not (and elt (frame-live-p (setq frame (nth 1 elt)))))
(setq frame (make-frame-on-display display (list (cons 'name name)))))
(if (not (and elt (buffer-name (get-buffer (setq buffer (nth 2 elt))))))
(setq buffer (get-buffer-create name)))
(cons (list display frame buffer) (delq elt talk-display-alist)))))
(defun talk-disconnect ()
"Disconnect this display from the Emacs talk group."
(let* ((mydisp (cdr (assq 'display (frame-parameters (selected-frame)))))
(elt (assoc mydisp talk-display-alist)))
(delete-frame (nth 1 elt))
(kill-buffer (nth 2 elt))
(setq talk-display-alist (delq elt talk-display-alist))
(defun talk-update-buffers ()
"Update all the talk frames so that each shows all the talk buffers."
(let ((tail talk-display-alist))
(let ((frame (nth 1 (car tail)))
(this-buffer (nth 2 (car tail)))
(mapcar (function (lambda (elt) (nth 2 elt)))
;; Put this display's own talk buffer
;; at the front of the list.
(setq buffers (cons this-buffer (delq this-buffer buffers)))
(talk-split-up-frame frame buffers))
(setq tail (cdr tail)))))
(defun talk-split-up-frame (frame buffers)
"Split FRAME into equal-sized windows displaying the buffers in BUFFERS.
Select the first of these windows, displaying the first of the buffers."
(let ((lines-per-buffer (/ (frame-height frame) (length buffers)))
(select-window (frame-first-window frame))
(switch-to-buffer (car buffers))
(setq buffers (cdr buffers)))
(select-window (frame-first-window frame)))
;;; talk.el ends here