/***************************************************************************
  This code is from Dynamic Web Coding at www.dyn-web.com
  Copyright 2004 by Sharon Paine 
  See Terms of Use at www.dyn-web.com/bus/terms.html
  regarding conditions under which you may use this code.
  This notice must be retained in the code as is!
****************************************************************************/

//if (document.getElementById('holder1') ){
	
	/*
	  dw_scroll_aux.js    version date: May 2004  
	  integrates scrolling layers code with scrollbar code (dw_scrollbar.js)
	*/
	
	// Size dragBar according to layer size?  
	dw_scrollObj.prototype.bSizeDragBar = true;
	
	dw_scrollObj.prototype.setUpScrollbar = function(id, trkId, axis, offx, offy) {
	  if (!document.getElementById) return;
	  var bar = document.getElementById(id);
	  var trk = document.getElementById(trkId);
	  dw_slidebar.init(bar, trk, axis, offx, offy);
	  // connect dw_slidebar with dw_scrollObj
	  bar.wn = dw_scrollObjs[this.id]; // scroll area object this bar connected to
	  if (axis == "v") this.vBarId = id; else this.hBarId = id;
	  // also called on_load (i.e., when layer loaded), but in case h and v scrollbars, need to call here too
	  if (this.bSizeDragBar) this.setBarSize();
	  bar.on_drag_start = bar.on_slide_start = dw_scrollObj.getWndoLyrRef;
	  bar.on_drag_end =   bar.on_slide_end =   dw_scrollObj.tossWndoLyrRef;
	  bar.on_drag =       bar.on_slide =       dw_scrollObj.UpdateWndoLyrPos;
	}
	
	// for these 3 functions (assigned to bar.on_drag/slide...) "this" refers to bar
	// get/discard ref to layer visible in scroll area
	dw_scrollObj.getWndoLyrRef = function()  { this.wnLyr = document.getElementById(this.wn.lyrId); }
	dw_scrollObj.tossWndoLyrRef = function() { this.wnLyr = null; }
	// keep position of scrolling layer in synch with slide/drag of bar
	dw_scrollObj.UpdateWndoLyrPos = function(x, y) {
	  var nx, ny;
	  if (this.axis == "v") {
		nx = this.wn.x; // floating point values for loaded layer's position held in shiftTo method
		ny = -(y - this.minY) * ( this.wn.maxY / (this.maxY - this.minY) ) || 0;
	  } else {
		ny = this.wn.y;
		nx = -(x - this.minX) * ( this.wn.maxX / (this.maxX - this.minX) ) || 0;
	  }
	  this.wn.shiftTo(this.wnLyr, nx, ny);
	}
	
	// Keep position of dragBar in sync with position of layer onscroll
	dw_scrollObj.prototype.updateScrollbar = function(x, y) {
	  var nx, ny;
	  if ( this.vBarId ) {
		if (!this.maxY) return;
		ny = -( y * ( (this.vbar.maxY - this.vbar.minY) / this.maxY ) - this.vbar.minY );
		ny = Math.min( Math.max(ny, this.vbar.minY), this.vbar.maxY);  
		nx = parseInt(this.vbar.style.left);
		this.vbar.style.left = nx + "px"; this.vbar.style.top = ny + "px";
	  } if ( this.hBarId ) {
		if (!this.maxX) return;
		nx = -( x * ( (this.hbar.maxX - this.hbar.minX) / this.maxX ) - this.hbar.minX );
		nx = Math.min( Math.max(nx, this.hbar.minX), this.hbar.maxX);
		ny = parseInt(this.hbar.style.top);
		this.hbar.style.left = nx + "px"; this.hbar.style.top = ny + "px";
	  } 
	  
	}
	
	// Restore dragBar to start position when loading new layer
	dw_scrollObj.prototype.restoreScrollbars = function() {
	  var bar;
	  if (this.vBarId) {
		bar = document.getElementById(this.vBarId);
		bar.style.left = bar.minX + "px"; bar.style.top = bar.minY + "px";
	  }
	  if (this.hBarId) {
		bar = document.getElementById(this.hBarId);
		bar.style.left = bar.minX + "px"; bar.style.top = bar.minY + "px";
	  }
	}
	  
	// Size dragBar in proportion to size of content in layer
	// called on_load of layer if bSizeDragBar prop true
	dw_scrollObj.prototype.setBarSize = function() {
	  var bar;
	  var lyr = document.getElementById(this.lyrId);
	  var wn = document.getElementById(this.id);
	  if (this.vBarId) {
		bar = document.getElementById(this.vBarId);
		bar.style.height = (lyr.offsetHeight > wn.offsetHeight)? bar.trkHt / ( lyr.offsetHeight / wn.offsetHeight ) + "px": bar.trkHt - 2*bar.minY + "px";
		bar.maxY = bar.trkHt - bar.offsetHeight - bar.minY; 
	  }
	  if (this.hBarId) {
		bar = document.getElementById(this.hBarId);
		bar.style.width = (this.wd > wn.offsetWidth)? bar.trkWd / ( this.wd / wn.offsetWidth ) + "px": bar.trkWd - 2*bar.minX + "px";
		bar.maxX = bar.trkWd - bar.offsetWidth - bar.minX; 
	  }
	}
	
	// called from load method
	dw_scrollObj.prototype.on_load = function() { 
	  this.restoreScrollbars();
	  if (this.bSizeDragBar) this.setBarSize();
	}
	
	dw_scrollObj.prototype.on_scroll = dw_scrollObj.prototype.on_slide = function(x,y) { this.updateScrollbar(x,y); }
	
	// obtain and discard references to relevant dragBar
	dw_scrollObj.prototype.on_scroll_start = dw_scrollObj.prototype.on_slide_start = function() {
	  if ( this.vBarId ) this.vbar = document.getElementById(this.vBarId);
	  if ( this.hBarId ) this.hbar = document.getElementById(this.hBarId);
	}
	
	dw_scrollObj.prototype.on_scroll_end = dw_scrollObj.prototype.on_slide_end = function(x, y) { 
	  this.updateScrollbar(x,y);
	  this.lyr = null; this.bar = null; 
	}
//}