(define NULL (ascii->char 0))

(define demo
  (lambda ()
    (let ((win (init-screen)))
      (keypad win #t)
      (noecho)
      
      (make&install-input-field win 
				20 10
				42 23
				"
   +----------------------------------+
   | f1  : move left  input-field     |
   | f2  : move right input-field     |
   | f3  : move up    input-field     |
   | f4  : move down  input-field     |
   |                                  |
   | f5  : make bigger in x direction |
   | f6  : make smaler in x direction |
   | f7  : make bigger in y direction |
   | f8  : make smaler in y direction |
   |                                  |
   | f9  : toggle x-scroll            |
   | f10 : toggle y-scroll            |
   |                                  |
   | f11 : clear                      |
   | f12 : reset                      |
   |                                  |
   | tab : toggle insert              |
   |                                  |
   | ESC : quit                       |
   +----------------------------------+

0-0 0-1 0-2 0-3 0-4 0-5
1-0 1-1 1-2 1-3 1-4 1-5 1-6
2-0 2-1 2-2 2-3 2-4 2-5 2-6 2-7
3-0 3-1 3-2 3-3 3-4 3-5 3-6 3-7 3-8
4-0 4-1 4-2 4-3 4-4 4-5 4-6 4-7 4-8 4-9
5-0 5-1 5-2 5-3 5-4 5-5 5-6 5-7 5-8 4-9
6-0 6-1 6-2 6-3 6-4 6-5 6-6 6-7 6-8
7-0 7-1 7-2 7-3 7-4 7-5 7-6 7-7
8-0 8-1 8-2 8-3 8-4 8-5 8-6
9-0 9-1 9-2 9-3 9-4 9-5\n"
				(append
				 (list (cons 9 ;; tab
					     'toggle-insert)
				       (cons key-ppage
					     'move-backward)
				       (cons key-npage
					     'move-forward))
				 standard-behavior-pro)
				#t #t #t)

      (wmove win 10 20)
      (screen-refresh win)

      (letrec ((else-loop (lambda (asc)
			    (let ((infl (cursor-over-input-field? win)))
			      (cond ((= asc 27)
				     (wclear win)
				     (clear)
				     (echo)
				     (endwin))
				    ((= asc key-f1)
				     (input-field-move infl 
						       (- (input-field-x-location infl)
							  1)
						       (input-field-y-location infl))
				     (screen-refresh win)
				     (loop (wgetch win)))
				    ((= asc key-f2)
				     (input-field-move infl 
						       (+ (input-field-x-location infl)
							  1)
						       (input-field-y-location infl))
				     (screen-refresh win)
				     (loop (wgetch win)))
				    ((= asc key-f3)
				     (input-field-move infl 
						       (input-field-x-location infl)
						       (- (input-field-y-location infl)
							  1))						       
				     (screen-refresh win)
				     (loop (wgetch win)))
				    ((= asc key-f4)
				     (input-field-move infl 
						       (input-field-x-location infl)
						       (+ (input-field-y-location infl)
							  1))
				     (screen-refresh win)
				     (loop (wgetch win)))
				    ((= asc key-f5)
				     (input-field-resize infl 
							 (+ (input-field-x-size infl)
							    1)
							 (input-field-y-size infl))
				     (screen-refresh win)
				     (loop (wgetch win)))
				    ((= asc key-f6)
				     (input-field-resize infl 
							 (- (input-field-x-size infl)
							    1)
							 (input-field-y-size infl))
				     (screen-refresh win)
				     (loop (wgetch win)))
				    ((= asc key-f7)
				     (input-field-resize infl 
							 (input-field-x-size infl)
							 (+ (input-field-y-size infl)
							    1))
				     (screen-refresh win)
				     (loop (wgetch win)))
				    ((= asc key-f8)
				     (input-field-resize infl 
							 (input-field-x-size infl)
							 (- (input-field-y-size infl)
							    1))
				     (screen-refresh win)
				     (loop (wgetch win)))
				    ((= asc key-f9)
				     (input-field-toggle-x-scroll infl)
				     (wrefresh win)
				     (loop (wgetch win)))
				    ((= asc key-f10)
				     (input-field-toggle-y-scroll infl)
				     (wrefresh win)
				     (loop (wgetch win)))
				    ((= asc key-f11)
				     (input-field-clear infl)
				     (wrefresh win)
				     (loop (wgetch win)))
				    ((= asc key-f12)
				     (input-field-reset infl)
				     (wrefresh win)
				     (loop (wgetch win)))
				    (else (loop (wgetch win)))))))
	       (loop (lambda (asc)
		       (cond ((cursor-over-input-field? win)
			      => (lambda (infl)
				   (call-with-values
				       (lambda ()
					 (send-input-field infl asc))
				     (lambda (was-known is-changed)
				       (if is-changed
					   (begin
					     (wrefresh win)
					     (loop (wgetch win)))
					   (if was-known
					       (loop (wgetch win))
					       (else-loop asc)))))))))))
	(loop (wgetch win))))))

						     
(define screen-refresh
  (lambda (screen)
    (let ((infl (cursor-over-input-field? screen))
	  (x (getx screen))
	  (y (gety screen)))
      (wclear screen)
      (input-field-refresh infl)
      (wdraw-box screen
		 (- (input-field-x-location infl) 1)
		 (- (input-field-y-location infl) 1)
		 (+ (input-field-x-size     infl) 2)
		 (+ (input-field-y-size     infl) 2))
      (wmove screen y x)
      (wrefresh screen))))

(define wdraw-box
  (lambda (win x y dimx dimy)
    (mvwaddstr win 
	       y          
	       x         "+")
    (mvwaddstr win 
	       y          
	       (+ dimx 
		  (- x
		     1)) "+")
    (mvwaddstr win 
	       (+ dimy 
		  (- y
		     1)) 
	       x          "+")
    (mvwaddstr win 
	       (+ dimy 
		  (- y
		     1)) 
	       (+ dimx 
		  (- x
		     1)) "+")
    (let loop-x ((dx  (+ x 1)))
      (if (= dx (+ x (- dimx 2)))
	  (begin
	    (mvwaddstr win y        dx "-")
	    (mvwaddstr win (+ dimy 
			      (- y
				 1)) dx "-"))
	  (begin 
	    (mvwaddstr win y        dx "-")
	    (mvwaddstr win (+ dimy 
			      (- y
				 1)) dx "-")
	    (loop-x (+ dx 1)))))
    (let loop-y ((dy  (+ y 1)))
      (if (= dy (+ y (- dimy 2)))
	  (begin
	    (mvwaddstr win dy x         "|")
	    (mvwaddstr win dy (+ dimx 
				 (- x
				    1)) "|"))
	  (begin 
	    (mvwaddstr win dy x         "|")
	    (mvwaddstr win dy (+ dimx 
				 (- x
				    1)) "|")
	    (loop-y (+ dy 1)))))))