#lang racket/gui

;;; api2.rkt - Editeurs de texte (page 322)
;;; Chapitre 14 (Objets et API graphique)
;;; Livre PCPS : "Premiers Cours de Programmation avec Scheme"
;;; Langage determine par le source

(require (only-in mzlib/string read-from-string-all expr->string))

"INTERFACE GRAPHIQUE : EDITEURS DE TEXTE"

(define-values (w h) (get-display-size))

(define FRAME 
  (let-values (((w h) (get-display-size)))
    (new frame% (min-width (quotient w 3)) (label "Editeurs") (x (quotient w 3)) (y 30))))

(define VPANEL (new vertical-panel% (parent FRAME) (alignment '(center center))))

(define TEXT1 (new text%))

(define TEXT2 (new text%))

(define ECANVAS1 (new editor-canvas% 
                      (parent VPANEL) (min-height 200) (editor TEXT1)))

(define ECANVAS2 (new editor-canvas% 
                      (parent VPANEL) (min-height 200) (editor TEXT2)))

(define ns (make-base-namespace))
(eval '(require scheme) ns)

(define BUTTON-EVAL 
  (new button% (parent VPANEL) 
       (label "Evaluer")
       (style '(border))
       (callback (lambda (b e)                ; b=button, e=event
                   (send TEXT2 erase)
                   (changer-le-style! TEXT2)
                   (let ((L (read-from-string-all (send TEXT1 get-text)))) 
                     (for-each (lambda (expr) 
                                 (send TEXT2 insert (expr->string (eval expr ns)))
                                 (send TEXT2 insert "\n"))
                               L))))))

(define (changer-le-style! t)
  (send t change-style 
        (make-object style-delta% 'change-family 'modern))
;  (send t change-style 
;        (make-object style-delta% 'change-bold))
  (send t change-style 
        (make-object style-delta% 'change-size 20)))

(changer-le-style! TEXT1)
(send TEXT1 insert "; Entrez des expressions Scheme\n; dans le cadre du haut.\n")
(send FRAME show #t)          ; run, Forrest, run !