;;;;
;;;; Dialog box creation utility
;;;;
;;;; Copyright © 1993-1998 Erick Gallesio - I3S-CNRS/ESSI <eg@unice.fr>
;;;; 
;;;; Permission to use, copy, and/or distribute this software and its
;;;; documentation for any purpose and without fee is hereby granted, provided
;;;; that both the above copyright notice and this permission notice appear in
;;;; all copies and derived works.  Fees for distribution or use of this
;;;; software or derived works may only be charged with express written
;;;; permission of the copyright holder.  
;;;; This software is provided ``as is'' without express or implied warranty.
;;;;
;;;; This software is a derivative work of other copyrighted softwares; the
;;;; copyright notices of these softwares are placed in the file COPYRIGHTS
;;;;
;;;;
;;;;           Author: Erick Gallesio [eg@unice.fr]
;;;;    Creation date:  4-Aug-1993 11:05
;;;; Last file update: 13-Jan-1998 10:12
;;;;

(provide "dialog")

(select-module Tk)

(define stk::button-pressed #f)
;;
;; STk:make-dialog
;;
;; This procedure displays a dialog box following the spcifications given in
;; arguments. Arguments are given as keywords.
;;
;; window (.dialog)	Window name to use for dialog top-level.
;; title ("Dialog")	Title to display in dialog's decorative frame.
;; text ("")		Message to display in dialog.
;; bitmap ("")		Bitmap to display in dialog (empty string means none).
;; default (-1) 	Index of button that is to display the default ring
;;			(-1 means none).
;; grab (#f)		Indicates if make-dialog must wait that a button be
;;			pressed before returning. Use 'global to heve a global
;;			grab.
;; buttons ('())	A list of couples indicating the button text and its
;;			associated action (a closure)
;;
;; If grabbing is set, this procedure returns the button pressed index.
;;

(define (STk:make-dialog . arguments)
  (let ((w 	   (get-keyword :window  arguments '.dialog))
	(title	   (get-keyword :title   arguments "Dialog"))
	(text	   (get-keyword :text    arguments ""))
	(bitmap    (get-keyword :bitmap  arguments ""))
	(default   (get-keyword :default arguments -1))
	(grabbing  (get-keyword :grab    arguments #f))
	(buttons   (get-keyword :buttons arguments '()))
	(old-focus (Tk:focus)))

    (catch (Tk:destroy w))
    (set! stk::button-pressed #f)

    ;; 1. Create the top-level window and divide it into top and bottom parts.
    (define w.top (format #f "~A.top" w))
    (define w.bot (format #f "~A.bot" w))
    (define w.msg (format #f "~A.top.msg" w))
    (define w.bmp (format #f "~A.top.bmp" w))

    (Tk:toplevel w :class "Dialog")
    (Tk:wm 'title w title)
    (Tk:wm 'iconname w "Dialog")
	
    (Tk:pack [Tk:frame w.top :relief "raised" :bd 1] :expand #t :fill "both")
    (Tk:pack [Tk:frame w.bot :relief "raised" :bd 1] :fill "x")

    ;; 2. Fill the top part with bitmap and message (use the option
    ;;    database for -wraplength so that it can be overridden by
    ;;    the caller).

    (option 'add "*Dialog.msg.wrapLength" "3i" "widgetDefault")
    (Tk:pack [message w.msg :justify "left" :text text :aspect 1000 
		      :font "-Adobe-Times-Medium-R-Normal-*-180-*"]
	     :side "right"
	     :expand #t 
	     :padx 10
	     :pady 10
	     :fill "both")

    (unless (equal? bitmap "")
	(Tk:pack [Tk:label w.bmp :bitmap bitmap :fg "red"]
		 :side "left"
		 :padx 10
		 :pady 10))

    ;; 3. Create a row of buttons at the bottom of the dialog.
    (do ([i 0 (+ i 1)] [but buttons (cdr but)])
	([null? but] '())
      
      (let ((name (format #f "~A.but-~A" w  i)))
	(Tk:button name :text (caar but) 
		   	:command (lambda ()
				   (if old-focus (Tk:focus old-focus))
				   (set! stk::button-pressed i)
				   (Tk:destroy w)
				   (apply (cadar but) '())))
	(if (equal? i default)
	    (Tk:focus name))
	(Tk:pack name :side "left" :expand #t :padx 20 :pady 8 :ipadx 2 :ipady 2)))

    ;; 4. Center window
    (STk:center-window w)

    ;; 5. Wait until a button is pressed if grab is set 
    (when grabbing
      (let* ((old-grab    (Tk:grab 'current *root*))
	     (grab-status (if old-grab
			      (grab 'status old-grab)
			      #f)))
	(if (eqv? grabbing 'global) 
	    (Tk:grab :global '.dialog)
	    (Tk:grab 'set w))

	;; Add a binding that sets the result to -1 if the window is detroyed
	(bind w "<Destroy>" (lambda () 
			      (unless stk::button-pressed
				  (set! stk::button-pressed -1))))

	(Tk:tkwait 'variable 'stk::button-pressed)
	(if old-grab
	    (if (equal? grab-status "global")
		(Tk:grab :global old-grab)
		(Tk:grab old-grab))))
	stk::button-pressed)))


(define (STk:center-window w)
  ;; Withdraw the window, then update all the geometry information
  ;; so we know how big it wants to be, then center the window in the
  ;; display and de-iconify it.

  (wm 'withdraw w)
  (update 'idletasks)
  (let ((x (- (/ [winfo 'screenwidth w] 2) 
	      (/ [winfo 'reqwidth w] 2)
	      (winfo 'vrootx [eval [winfo 'parent w]])))
	(y (- (/ [winfo 'screenheight w] 2)
	      (/ [winfo 'reqheight w] 2)
	      (winfo 'vrooty [eval [winfo 'parent w]]))))
    (wm 'geom w (format #f "+~A+~A" (inexact->exact (floor x)) 
				    (inexact->exact (floor y))))
    (wm 'deiconify w)))


;;;;; Compatibility
(define stk::make-dialog STk:make-dialog)