// Create namespace
if (at == undefined) var at = {};
if (at.bartelme == undefined) at.bartelme = {};

// Newsticker Class
at.bartelme.newsticker = Class.create();
at.bartelme.newsticker.prototype = {
  initialize: function(id)
  {
    // Get elements
    this.interval = 6000;
    this.container = $(id);
    this.messages  = $A(this.container.getElementsByTagName("li"));
    this.number_of_messages = this.messages.length;
    if (this.number_of_messages == 0)
    {
      this.showError();
      return false;
    }
    this.current_message = 0;
    this.previous_message = null;

    this.hideMessages();
    this.showMessage();
    // Install timer
    if(this.messages.length>1) this.timer = setInterval(this.showMessage.bind(this), this.interval);
    },
  showMessage: function()
  {
    Effect.Appear(this.messages[this.current_message],{duration: 0.3});
    if(this.messages.length>1) setTimeout(this.fadeMessage.bind(this), this.interval-500);
    if (this.current_message < this.number_of_messages-1)
    {
      this.previous_message = this.current_message;
      this.current_message = this.current_message + 1;
    } else {
      this.current_message = 0;
      this.previous_message = this.number_of_messages - 1;
    }
  },
  fadeMessage: function()
  {
    Effect.Fade(this.messages[this.previous_message],{duration: 0.3});
  },
  hideMessages: function()
  {
    this.messages.each(function(message)
    {
      Element.hide(message);
    })
  },
  showError: function()
  {
    if (this.container.getElementsByTagName("ul").length == 0)
    {
      this.list = document.createElement("ul");
      this.container.appendChild(this.list);
    } else {
      this.list = this.container.getElementsByTagName("ul")[0];
    }
    this.errorMessage = document.createElement("li");
    this.errorMessage.className = "error";
    this.errorMessage.innerHTML = "Could not retrieve data";
    this.list.appendChild(this.errorMessage);
  }
}