/*************************************************************************
  This code is from Dynamic Web Coding at www.dyn-web.com
  Copyright 2001-4 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!
*************************************************************************/

/*
    continuous horizontal scroller - version date: May 2004
    (scroller content in html doc)
*/

// Arguments: id of content layer (inside wn), 
// id of nested element that contains scrolling content (table recommended for images)
// speed, set up mouse events? (boolean)
function dw_chScroller(id, id2, speed, bMouse) {
  this.id=id; this.el = document.getElementById? document.getElementById(id): null; 
  if (!this.el) return; this.css = this.el.style; 
  this.css.left = this.x = 0; this.css.top = this.y = 0;
  this.speed = speed || 160; 
  if (bMouse) dw_scrollers.setMouseEvents(this.el);
  this.w = document.getElementById(id2).offsetWidth;
  this.index = dw_scrollers.ar.length;  dw_scrollers.ar[this.index] = this;
  this.lastTime = new Date().getTime(); this.active = true;
}

dw_chScroller.prototype.controlScroll = function() {
  if (this.x > -this.w/2) { 
  	var nx = this.x + -1 * this.elapsed/600 * this.speed;
    nx = Math.max(nx, -this.w/2);
    this.shiftTo(nx, 0);	
  } else this.shiftTo(0, 0);	
}

dw_chScroller.prototype.shiftTo = function(x, y) {
  this.css.left = (this.x = x) + "px";
  this.css.top = (this.y = y) + "px";
}

////////////////////////////////////////////////////////////////////////////
// common to all scrollers (pausing or continuous, vertical or horizontal)
dw_scrollers = {};  
dw_scrollers.ar = []; // global access to all scroller instances

dw_scrollers.setMouseEvents = function(obj) {
  obj.onmouseover = dw_scrollers.halt;
  obj.onmouseout = dw_scrollers.resume;
}

dw_scrollers.halt = function() {
  var i, curObj;
  for (i=0; curObj = dw_scrollers.ar[i]; i++) 
    if ( curObj.id == this.id ) { curObj.active = false; return; }
}

dw_scrollers.resume = function(e) {
  var i, curObj, toEl, now;
  for (i=0; curObj = dw_scrollers.ar[i]; i++) {
    if ( curObj.id == this.id ) {
      e = e? e: window.event;
      toEl = e.relatedTarget? e.relatedTarget: e.toElement;
      if ( this != toEl && !contained(toEl, this) ) { 
        now = new Date().getTime();
        curObj.elapsed = now - curObj.lastTime;
        curObj.lastTime = now; curObj.active = true; return; 
      }
    }
  }
}

dw_scrollers.callRate = 10;
// Handle all instances with one timer - idea from youngpup.net
dw_scrollers.timer = window.setInterval("dw_scrollers.control()", dw_scrollers.callRate);
dw_scrollers.control = function() {
  var i, curObj, now;
  for (i=0; curObj = dw_scrollers.ar[i]; i++) {
    if ( curObj.active ) {
      now = new Date().getTime();
      curObj.elapsed = now - curObj.lastTime;
      curObj.lastTime = now; curObj.controlScroll();
    }
  }
}

// remove layers from table for ns6+/mozilla (needed for scrollers inside tables)
// pass id's of scrollers (i.e., div's that contain content that scrolls, usually wn, or wn1, ...)
dw_scrollers.GeckoTableFix = function() {
  var i, wndo, holderId, holder, x, y;
	if ( navigator.userAgent.indexOf("Gecko") > -1 && navigator.userAgent.indexOf("Firefox") == -1 ) {
    dw_scrollers.hold = []; // holds id's of wndo (i.e., 'the scroller') and its container
    for (i=0; arguments[i]; i++) {
      wndo = document.getElementById( arguments[i] );
      holderId = wndo.parentNode.id;
      holder = document.getElementById(holderId);
      document.body.appendChild( holder.removeChild(wndo) );
      wndo.style.zIndex = 1000;
      x = holder.offsetLeft; y = holder.offsetTop;
      wndo.style.left = x + "px"; wndo.style.top = y + "px";
      dw_scrollers.hold[i] = [ arguments[i], holderId ];
    }
   window.addEventListener("resize", dw_scrollers.rePosition, true);
  }
}

// ns6+/mozilla need to reposition layers onresize when scrollers inside tables.
dw_scrollers.rePosition = function() {
  var i, wndo, holder, x, y;
  if (dw_scrollers.hold) {
    for (i=0; dw_scrollers.hold[i]; i++) {
      wndo = document.getElementById( dw_scrollers.hold[i][0] );
      holder = document.getElementById( dw_scrollers.hold[i][1] );
      x = holder.offsetLeft; y = holder.offsetTop;
      wndo.style.left = x + "px"; wndo.style.top = y + "px";
    }
  }
}

// returns true if oNode is contained by oCont (container)
function contained(oNode, oCont) {
  if (!oNode) return; // in case alt-tab away while hovering (prevent error)
  while ( oNode = oNode.parentNode ) if ( oNode == oCont ) return true;
  return false;
}

// avoid memory leak in ie
dw_scrollers.unHook = function() {
  var i, curObj;
  for (i=0; curObj = dw_scrollers.ar[i]; i++) {
    if ( curObj.el ) { 
      curObj.el.onmouseover = null;
      curObj.el.onmouseout = null;
      curObj.el = null;
    }
  }
}

if ( window.addEventListener ) window.addEventListener( "unload", dw_scrollers.unHook, true);
else if ( window.attachEvent ) window.attachEvent( "onunload", dw_scrollers.unHook );
