/*
The contents of this file are subject to the Netscape Public
License Version 1.1 (the "License"); you may not use this file
except in compliance with the License. You may obtain a copy of
the License at http://www.mozilla.org/NPL/

Software distributed under the License is distributed on an "AS
IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
implied. See the License for the specific language governing
rights and limitations under the License.

The Initial Developer of the Original Code is Doron Rosenberg

Contributor(s):  Doron Rosenberg, doronr@gmx.net
                 Bob Clary, Netscape Communications, Copyright 2001
*/


function Ticker(name, id, shiftBy, interval)
{
  this.name     = name;
  this.id       = id;
  this.shiftBy  = shiftBy ? shiftBy : 1;
  this.interval = interval ? interval : 100;
  this.runId	= null;

  this.div = document.getElementById(id);

  var node = this.div.firstChild;
  var next;

  while (node)
  {
    next = node.nextSibling;
    if (node.nodeType == 3)
      this.div.removeChild(node);
    node = next;
  }

  this.left = 0;
  this.shiftLeftAt = this.div.firstChild.offsetWidth;
  this.div.style.height	= this.div.firstChild.offsetHeight;
  this.div.style.width = 2 * screen.availWidth;
  this.div.style.visibility = 'visible';
  
  var n=Math.floor(Math.random()*30)
  while (n > 0)
  {
  	this.div.appendChild(this.div.firstChild)
  	n--;
  }
}

function startTicker()
{
  this.stop();
  
  this.left -= this.shiftBy;

  if (this.left <= -this.shiftLeftAt)
  {
    this.left = 0;
    this.div.appendChild(this.div.firstChild);
  
    this.shiftLeftAt = this.div.firstChild.offsetWidth;
  }

  this.div.style.left = (this.left + 'px');

  this.runId = setTimeout(this.name + '.start()', this.interval);
}

function stopTicker()
{
  if (this.runId)
    clearTimeout(this.runId);
    
  this.runId = null;
}

function changeTickerInterval(newinterval)
{

  if (typeof(newinterval) == 'string')
    newinterval =  parseInt('0' + newinterval, 10); 
	
  if (typeof(newinterval) == 'number' && newinterval > 0)
    this.interval = newinterval;
    
    this.stop();
    this.start();
}

Ticker.prototype.start = startTicker;
Ticker.prototype.stop = stopTicker;
Ticker.prototype.changeInterval = changeTickerInterval;