;;;;
;;;; P a n e d . s t k 	  	      --  HPaned and VPaned composite widgets
;;;;
;;;; Copyright © 1993-1996 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.
;;;;
;;;; Idea of this implementation was found in comp.lang.tcl. 
;;;; Original author seems to be James Noble and the version from which this 
;;;; stuff is derivated is Jay Schmidgall (shmdgljd@ghostwind.rchland.ibm.com).
;;;;
;;;;           Author: Erick Gallesio [eg@kaolin.unice.fr]
;;;;    Creation date: 22-Mar-1994 13:05
;;;; Last file update: 13-Aug-1996 23:22

(require "Frame")

(define paned:drag-start 0)

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;
;;;; <HPaned> class definition
;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define-class <HPaned> (<Tk-composite-widget>)
  ((top-frame    :accessor     top-frame-of)
   (bottom-frame :accessor     bottom-frame-of)
   (grip	 :accessor     grip-of)
   (separator	 :accessor     separator-of)
   (fraction     :init-keyword :fraction)
   ;; Fictives slot
   (background   :accessor     background
		 :init-keyword :background
		 :allocation   :propagated
		 :propagate-to (frame top-frame bottom-frame grip separator))
   (width	 :accessor     width
		 :init-keyword :width
		 :allocation   :propagated
		 :propagate-to (frame))
   (height	 :accessor     height
		 :init-keyword :height
		 :allocation   :propagated
		 :propagate-to (frame))))


(define-method initialize-composite-widget ((self <HPaned>) initargs frame)
  (let ((grip  (make <Frame> :parent frame :width 10 :height 10 :border-width 2 
		    	     :relief "raised"  :cursor "crosshair"))
	(separ (make <Frame> :parent frame :width 1 :height 4
		     	     :border-width 2 :relief "ridge"))
	(top   (make <Frame> :parent frame :border-width 2 :relief "raised"))
	(bot   (make <Frame> :parent frame :border-width 2 :relief "raised")))

    
    ;; Associate bindings to the grip
    (bind grip "<Button-1>"  		(lambda (y) (start-grip  self y)))
    (bind grip "<B1-Motion>" 		(lambda (y) (motion-grip self y)))
    (bind grip "<B1-ButtonRelease-1>" 	(lambda (y) (stop-grip   self y)))

    ;; initialize true slots
    (slot-set! self 'Id           (Id frame))
    (slot-set! self 'top-frame    top)
    (slot-set! self 'bottom-frame bot)
    (slot-set! self 'grip 	  grip)
    (slot-set! self 'separator 	  separ)
    (slot-set! self 'fraction 	  (get-keyword :fraction initargs 0.5))

    ;; Place the grip
    (place-grip self)))
   

;;;
;;; <HPaned> methods 
;;; 
(define-method place-grip ((self <HPaned>))
  (let ((fraction (slot-ref self 'fraction)))
    (place (separator-of self)    :relx 0    :rely fraction :anch "w" :relwi 1)
    (place (grip-of self)         :relx 0.95 :rely fraction :anchor "center")
    (place (top-frame-of self)    :x 0 :y 0 :relwidth 1 :relheight fraction)
    (place (bottom-frame-of self) :x 0 :rely fraction :relwidth 1 
				  :relheight (- 1.0 fraction))
    ;; Hide separator behind the bottom and top frames
    (lower (separator-of self))
    ;; Be sure to raise the grip 
    (raise (grip-of self))))

(define-method start-grip ((self <HPaned>) y)
  ;; Raise separator and grip 
  (raise (separator-of self))
  (raise (grip-of self))
  (set! paned:drag-start y))

(define-method motion-grip ((self <HPaned>) y)
  (let ((fraction (slot-ref self 'fraction)))
    (set! fraction (max 0.0001 
			(min 0.9999
			     (+ fraction 
				(/ (- y paned:drag-start) 
				   (+ 1 (winfo 'height (frame-of self))))))))
    (place (separator-of self) :relx 0 :relwidth 1 :rely fraction :anchor "w")
    (place (grip-of self)      :relx 0.95 :rely fraction :anchor "center")
    (slot-set! self 'fraction fraction)))

(define-method stop-grip ((self <HPaned>) y)
  (place-grip self))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;
;;;; <VPaned> class definition
;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define-class <VPaned> (<Tk-composite-widget>)
  ((left-frame   :accessor     left-frame-of)
   (right-frame  :accessor     right-frame-of)
   (grip	 :accessor     grip-of)
   (separator	 :accessor     separator-of)
   (fraction     :init-keyword :fraction)
   ;; Fictives slots
   (background   :accessor     background
		 :init-keyword :background
		 :allocation   :propagated
		 :propagate-to    (frame left-frame right-frame grip separator))
   (width	 :accessor     width
		 :init-keyword :width
		 :allocation   :propagated
		 :propagate-to (frame))
   (height	 :accessor     height
		 :init-keyword :height
		 :allocation   :propagated
		 :propagate-to (frame))))


(define-method initialize-composite-widget ((self <VPaned>) initargs frame)
  (let ((grip  (make <Frame> :parent frame :width 10 :height 10 :border-width 2 
		    	     :relief "raised"  :cursor "crosshair"))
	(separ (make <Frame> :parent frame :width 4 :height 1
		     	     :border-width 2 :relief "ridge"))
	(left   (make <Frame> :parent frame :border-width 2 :relief "raised"))
	(right  (make <Frame> :parent frame :border-width 2 :relief "raised")))

    
    ;; Associate bindings to the grip
    (bind grip "<Button-1>"  		(lambda (x) (start-grip  self x)))
    (bind grip "<B1-Motion>" 		(lambda (x) (motion-grip self x)))
    (bind grip "<B1-ButtonRelease-1>" 	(lambda (x) (stop-grip   self x)))

    ;; initialize true slots
    (slot-set! self 'Id           (Id frame))
    (slot-set! self 'left-frame   left)
    (slot-set! self 'right-frame  right)
    (slot-set! self 'grip 	  grip)
    (slot-set! self 'separator 	  separ)
    (slot-set! self 'fraction 	  (get-keyword :fraction initargs 0.5))

    ;; Place the grip
    (place-grip self)))
   

;;;
;;; <VPaned> methods 
;;; 
(define-method place-grip ((self <VPaned>))
  (let ((fraction (slot-ref self 'fraction)))
    (place (separator-of self)    :rely 0    :relx fraction :anch "n" :relh 1)
    (place (grip-of self)         :rely 0.95 :relx fraction :anchor "center")
    (place (left-frame-of self)   :x 0 :y 0 :relheight 1 :relwidth fraction)
    (place (right-frame-of self)  :y 0 :relx fraction :relheight 1 
				  :relwidth (- 1.0 fraction))
    ;; Hide separator behind the right and left frames
    (lower (separator-of self))
    ;; Be sure to raise the grip 
    (raise (grip-of self))))

(define-method start-grip ((self <VPaned>) x)
  ;; Raise separator and grip 
  (raise (separator-of self))
  (raise (grip-of self))
  (set! paned:drag-start x))

(define-method motion-grip ((self <VPaned>) x)
  (let ((fraction (slot-ref self 'fraction)))
    (set! fraction (max 0.0001 
			(min 0.9999
			     (+ fraction 
				(/ (- x paned:drag-start) 
				   (+ 1 (winfo 'width (frame-of self))))))))
    (place (separator-of self) :rely 0 :relheight 1 :relx fraction :anchor "n")
    (place (grip-of self)      :rely 0.95 :relx fraction :anchor "center")
    (slot-set! self 'fraction fraction)))

(define-method stop-grip ((self <VPaned>) x)
  (place-grip self))


(provide "Paned")