////////////////////// THE CYCLE OBJECT CLASS //////////////////////
// This is essentially a class which cycles through the div ids passed
// to it on creation
function CycleObject(ids, transType, onClass, offClass) {

  // Methods
  this.setVisible = function(index) {

    // Check if there is an indicator for the animation and set as appropriate
    if (this.indicators[this.currentlyVisible]) {
      this.indicators[this.currentlyVisible].removeClassName(this.onClass);
      this.indicators[this.currentlyVisible].addClassName(this.offClass);
    }

    if (this.indicators[index]) {
      this.indicators[index].removeClassName(this.offClass);
      this.indicators[index].addClassName(this.onClass);
    }

    switch(this.transType) {

      case 'normal':
        $(this.ids[this.currentlyVisible]).hide();

        $(this.ids[index]).show();

        this.currentlyVisible = index;
        break;

      case 'fade':
        new Effect.Fade(
          this.ids[this.currentlyVisible],
      		{
      			from: 1.0,
      			to: 0.0,
      			duration: 0.3,
      			queue: 'end'
      		}
      	);

      	new Effect.Appear(
          this.ids[index],
      		{
      			from: 0.0,
      			to: 1.0,
      			duration: 0.3,
      			queue: 'end'
      		}
      	);
        this.currentlyVisible = index;
        break;
    }
  }

  this.nextItem = function() {
    // If we're at the end of the list...
    if( this.currentlyVisible == this.ids.length - 1 ) {
      return false;
    } else {
      this.setVisible(this.currentlyVisible + 1);
      return true;
    }
  }

  this.prevItem = function() {
    // If we're at the beginning of the list...
    if( this.currentlyVisible == 0 ) {
      ;// do nothing
    } else {
      this.setVisible(this.currentlyVisible - 1);
    }
  }

  this.showItem = function(index) {
  	// show a particular item in the list and stop the animation
	this.cycleObject.stop();
  	this.setVisible(index);
  }

  this.startCycle = function() {
    this.cycleObject = new PeriodicalExecuter(
      this.onUpdateCycle.bind(this), 8 // this is the number of seconds between each interval
    );
  }

  this.stopCycle = function() {
    this.cycleObject.stop();
    this.cycleObject = null;
  }

  this.toggleCycle = function() {
    if (this.cycleObject == null) {
      this.startCycle();
    } else {
      this.stopCycle();
    }
  }

  this.onUpdateCycle = function (pe) {
    if (this.nextItem() == false) {
      this.setVisible(0);
    }
  }

  // Properties

  // An array of ids over which the object will cycle
  // First check that the id exists, if not, discard it
  this.ids = [];
  for(i = 0; i < ids.length; i++) {
    if($(ids[i]) != null) {
      this.ids.push(ids[i]);
    }
  }

  // Transition is 'fade' by default
  this.transType = typeof(transType) != 'undefined' ? transType : 'fade';

  this.onClass = typeof(onClass) != 'undefined' ? onClass : 'on';
  this.offClass = typeof(offClass) != 'undefined' ? offClass : 'off';

  // The index (of the array ids) of the currently visible div
  this.currentlyVisible = 0;

  // Initialisation
  this.cycleObject = null;

  // find if there are any indicators
  this.indicators = new Array(this.ids.length);

  for(i = 0; i < this.ids.length; i++){
    var indicatorLabel = this.ids[i]+'-indicator';
  	var indicator = $(indicatorLabel);
  	this.indicators[i] = indicator;
  }

  // Set the first one as visible and all the others as not
  for(i = 1; i < this.ids.length; i++){
    $(this.ids[i]).hide();
  }

  this.setVisible(0);

}


document.observe("dom:loaded", function() {
	startFeaturesCycle();
});

// Start features cycle box
function startFeaturesCycle() {
	if ( $("features") ) {
		featuresCycleBox = new CycleObject(['headcyc-1', 'headcyc-2', 'headcyc-3', 'headcyc-4', 'headcyc-5', 'headcyc-6']);
		featuresCycleBox.startCycle();
	
		var featuresLinks = $$('a.featurescyclelink');
			featuresLinks.each(
				function(link) {
					var itemNumber = link.id.replace('headline-rotate','')-1;
					link.observe('click',
						function() {
							featuresCycleBox.showItem(itemNumber);
						}
					)
				}
			);
	}
}