;; Author: David Frese

;; create-window takes an alist of names and values - see 
;; change-window-attributes and configure-window. Mandatory arguments for 
;; create-window are 'parent, 'width and 'height. Example:
;; (create-window 'parent root 'width 500 'height 300 '((border-width . 4)))
;; Returns the new window or raises an exception if something went wrong.

(define (create-window . args)
  (let ((alist (named-args->alist args)))
    (receive (x y width height border-width parent change-win-attr-list)
	     (alist-split alist '((x . 0) (y . 0) (width . #f) (height . #f)
				  (border-width . 2) (parent . #f)))
      (let* ((display (window-display parent))
	     (Xwindow (%create-window (display-Xdisplay display)
				      (window-Xwindow parent)
				      x y width height border-width
				      change-win-attr-list)))
	(if (= Xwindow 0)
	    (error "cannot create window")
	    (make-window Xwindow display))))))

(import-lambda-definition %create-window (Xdisplay Xparent x y width height 
						   border-width attrAlist)
  "Create_Window")

;; change-window-attributes takes an alist of names and values...
;; names can be: background-pixmap, background-pixel, border-pixmap, 
;; border-pixel, bit-gravity, gravity, backing-store, backing-planes, 
;; backing-pixel, save-under, event-mask, do-not-propagate-mask, 
;; override-redirect, colormap, cursor.

(define (change-window-attributes window . attrs)
  (let* ((alist (named-args->alist attrs))
	 (prep-alist 
	  (map cons
	       (map car alist)
	       (map (lambda (value)
		      (cond
		       ;; Abstractions ?? :
		       ((pixmap? value) (pixmap-Xpixmap value))
		       ((pixel? value) (pixel-Xpixel value))
		       ((colormap? value) (colormap-Xcolormap value))
;...		       ((cursor? value) (cursor-Xcursor value))
		       (else value)))
		    (map cdr alist)))))
    (%change-window-attributes (window-Xwindow window)
			       (display-Xdisplay (window-display window))
			       prep-alist)))

(import-lambda-definition %change-window-attributes (Xwindow Xdisplay alist)
  "Change_Window_Attributes")

;; simple functions that use change-window-attributes
;; TODO: a caching system for multiple calls to these functions

(define (make-win-attr-setter name)
  (lambda (window value)
    (change-window-attributes window (list (cons name value)))))

(define set-window-background-pixmap! (make-win-attr-setter 'background-pixmap))
(define set-window-background-pixel! (make-win-attr-setter 'background-pixel))
(define set-window-border-pixmap! (make-win-attr-setter 'border-pixmap))
(define set-window-border-pixel! (make-win-attr-setter 'border-pixel))
(define set-window-bit-gravity! (make-win-attr-setter 'bit-gravity))
(define set-window-gravity! (make-win-attr-setter 'gravity))
(define set-window-backing-store! (make-win-attr-setter 'backing-store))
(define set-window-backing-planes! (make-win-attr-setter 'backing-planes))
(define set-window-backing-pixel! (make-win-attr-setter 'backing-pixel))
(define set-window-save-under! (make-win-attr-setter 'save-under))
(define set-window-event-mask! (make-win-attr-setter 'event-mask))
(define set-window-do-not-propagate-mask! 
  (make-win-attr-setter 'do-not-propagate-mask))
(define set-window-override-redirect! (make-win-attr-setter 'override-redirect))
(define set-window-colormap! (make-win-attr-setter 'colormap))
(define set-window-cursor! (make-win-attr-setter 'cursor))

;; get-window-attributes gives back the same attributes that 
;; set-window-attributes sets and some more ... 

(define (get-window-attributes window)
  (let ((Xwindow (window-Xwindow window))
	(Xdisplay (display-Xdisplay (window-display window))))
    (let ((v (%get-window-attributes Xdisplay Xwindow)))
      (if (not v)
	  (error "cannot get window attributes." window)
	  (let*
	      ((comp (lambda (i f) (vector-set! v i (f (vector-ref v i)))))
	       (mod-v (begin
			(comp 13 make-pixel) ;; backing-pixel
			(comp 7 (lambda (Xwin) ;; root
				  ;; really this Display ??
				  (make-window Xwin (window-display window))))
			;; font, visual ??
			v))
	       (alist (map cons
			   '(x y width height border-width depth visual root 
			     class bit-gravity win-gravity backing-store 
			     backing-planes backing-pixel save-under colormap 
			     map-installed map-state all-event-masks 
			     your-event-mask do-not-propagate-mask 
			     override-redirect
			     ; screen not supported
			   )
			   (vector->list mod-v))))
	    alist)))))

(import-lambda-definition %get-window-attributes (Xdisplay Xwindow)
  "Get_Window_Attributes")

(define (make-win-attr-getter name)
  (lambda (window)
    (cdr (assq name (get-window-attributes window)))))

(define window-x (make-win-attr-getter 'x))
(define window-y (make-win-attr-getter 'y))
(define window-width (make-win-attr-getter 'width))
(define window-height (make-win-attr-getter 'height))
(define window-border-width (make-win-attr-getter 'border-width))
(define window-depth (make-win-attr-getter 'depth))
(define window-visual (make-win-attr-getter 'visual))
(define window-root (make-win-attr-getter 'root))
(define window-class (make-win-attr-getter 'class))
(define window-bit-gravity (make-win-attr-getter 'bit-gravity))
(define window-backing-store (make-win-attr-getter 'backing-store))
(define window-backing-planes (make-win-attr-getter 'backing-planes))
(define window-backing-pixel (make-win-attr-getter 'backing-pixel))
(define window-save-under (make-win-attr-getter 'save-under))
(define window-colormap (make-win-attr-getter 'colormap))
(define window-map-installed (make-win-attr-getter 'map-installed))
(define window-map-state (make-win-attr-getter 'map-state))
(define window-all-event-masks (make-win-attr-getter 'all-event-masks))
(define window-your-event-mask (make-win-attr-getter 'your-event-mask))
(define window-do-not-propagate-mask 
  (make-win-attr-getter 'do-not-propagate-mask))
(define window-override-redirect (make-win-attr-getter 'override-redirect))

;; This sets the window-attributes listed below - call like create-window.

(define (configure-window window . args)
  (let* ((args (named-args->alist args))
	 (prep-alist (map cons
			  (map car args)
			  (map (lambda (val)
				 (if (window? val)
				     (window-Xwindow val)
				     val))
			       (map cdr args)))))
  (%configure-window (window-Xwindow window)
		     (display-Xdisplay (window-display window))
		     prep-alist)))

(import-lambda-definition %configure-window (Xwindow Xdisplay alist)
  "Configure_Window")

;; the following mutators are based on configure-window

(define (make-win-configurer name)
  (lambda (window value)
    (configure-window window (list (cons name value)))))

(define set-window-x! (make-win-configurer 'x))
(define set-window-y! (make-win-configurer 'y))
(define set-window-width! (make-win-configurer 'width))
(define set-window-height! (make-win-configurer 'height))
(define set-window-border-width! (make-win-configurer 'border-width))
(define set-window-sibling! (make-win-configurer 'sibling))
(define set-window-stack-mode! (make-win-configurer 'stack-mode))

;; The map-window function maps the window and all of its subwindows that have 
;; had map requests. See XMapWindow.

(define (map-window window)
  (%map-window (window-Xwindow window) 
	       (display-Xdisplay (window-display window))))

(import-lambda-definition %map-window (Xwindow Xdisplay)
  "Map_Window")

;; The unmap-window function unmaps the specified window and causes the 
;; X server to generate an unmap-notify event. See XUnmapWindow.

(define (unmap-window window)
  (%unmap-window (window-Xwindow window)
		 (display-Xdisplay (window-display window))))

(import-lambda-definition %unmap-window (Xwindow Xdisplay)
  "Unmap_Window")

;; The destroy-subwindows function destroys all inferior windows of the 
;; specified window, in bottom-to-top stacking order. See XDestroySubWindows.

(define (destroy-subwindows window)
  (%destroy-subwindows (window-Xwindow window)
		       (display-Xdisplay (window-display window))))

(import-lambda-definition %destroy-subwindows (Xwindow Xdisplay)
  "Destroy_Subwindows")

;; The map-subwindows function maps all subwindows for a  specified window in 
;; top-to-bottom stacking order. See XMapSubwindows

(define (map-subwindows window)
  (%map-subwindows (window-Xwindow window)
		   (display-Xdisplay (window-display window))))

(import-lambda-definition %map-subwindows (Xwindow Xdisplay)
  "Map_Subwindows")

;; The unmap-subwindows function unmaps all subwindows for each subwindow 
;; and expose events on formerly obscured windows. See XUnmapSubwindow.

(define (unmap-subwindows window)
  (%unmap-subwindows (window-Xwindow window)
		     (display-Xdisplay (window-display window))))

(import-lambda-definition %unmap-subwindows (Xwindow Xdisplay)
  "Unmap_Subwindows")

;; See XCirculateSubwindows.

(define (circulate-subwindows window direction)
  (%destroy-subwindows (window-Xwindow window)
		       (display-Xdisplay (window-display window))
		       (eq? direction 'lower-highest)))
		       ; other is: 'raise-lower / exception??

(import-lambda-definition %circulate-subwindows (Xwindow Xdisplay dir)
  "Circulate_Subwindows")

;; The clear-window function clears the entire area in the specified window.
;; See XClearWindow.

(define (clear-window window)
  (clear-area window 0 0 0 0 #f))

;; The raise-window (lower-window) function raises (lowers) the specified window
;; to the top (button) of the stack so that no sibling window obscures it (it 
;; does not obscure any sibling windows). See XRaiseWindow.

(define (raise-window window)
  (set-window-stack-mode! window 'above))

(define (lower-window window)
  (set-window-stack-mode! window 'below))

;; The restack-windows function restacks the windows in the order specified, 
;; from top to bottom. The stacking order of the first window in the windows 
;; list is unaffected, but the other windows in the array are stacked underneath
;; the first window, in the order of the list. See XRestackWindows.

(define (restack-windows window-list)
  (let loop ((w (car window-list))
	     (t (cdr window-list)))
    (if (not (null? t))
	(let ((n (car t)))
	  (set-window-sibling! n w)
	  (set-window-stack-mode! n 'below)
	  (loop n (cdr t))))))

;; query-tree returns a list of three elements: root window, parent window and 
;; child windows of the given window. See XQueryTree.

(define (query-tree window)
  (let* ((display (window-display window))
	 (res (%query-tree (window-Xwindow window)
			   (display-Xdisplay display))))
    (list (make-window (first res) display)
	  (make-window (second res) display)
	  (vector-map! (lambda (Xwindow)
			 (make-window Xwindow display))
		       (third res)))))

(import-lambda-definition %query-tree (Xwindow Xdisplay)
  "Query_Tree")

;; translate-coordinates takes the x and y coordinates relative to the source 
;; window's origin and returns a list of three elements: the x and y coordinates
;; relative to the destination window's origin. If the source window and the 
;; destination window are on different screens the result is #f. See 
;; XTranslateCoordinates.

(define (translate-coordinates src-window x y dst-window)
  (let* ((display (window-display src-window))
	 (res (%translate-coordinates 
	       (display-Xdisplay display)
	       (window-Xwindow src-window)
	       x y
	       (window-Xwindow dst-window))))
    (if res
	(list (first res)
	      (second res)
	      (make-window (third res) display))
	#f)))

(import-lambda-definition %translate-coordinates (Xdisplay srcXwindow x y 
							   srcXwindow)
  "Translate_Coordinates")


;; query-pointer returns a list of eight elements: x and y coordinates, a 
;; boolean indicating whether the pointer is on the same screen as the specified
;; window, the root window, the root window's x and y coordinates, the child 
;; window and a list of modifier names (see grab-button). See XQueryPointer.

(define (query-pointer window)
  (let* ((display (window-display window))
	 (res (%query-pointer (display-Xdisplay display)
			      (window-Xwindow window))))
    (list (first res)
	  (second res)
	  (third res)
	  (make-window (fourth res) display)
	  (fifth res)
	  (sixth res)
	  (make-window (seventh res) display)
	  (eighth res))))

(import-lambda-definition %query-pointer (Xdisplay Xwindow)
  "Query_Pointer")