var ListSwitch = Class.create({
  initialize: function(initialElementId,selectedClass) {
    this.selected = initialElementId;
    this.selectedClass = selectedClass;
  },

  switchTo: function(selectedElementId) {
    if(selectedElementId != this.selected) {
        $(this.selected).removeClassName(this.selectedClass);
        this.selected = selectedElementId;
        $(this.selected).addClassName(this.selectedClass);
    }
  }
});

var ProductShow = Class.create({
    initialize: function(listSwitch,numSlides) {
        this.numSlides = numSlides;
        this.slideShown = 0;
        this.wait = 4000;
        this.listSwitch = listSwitch;        
    }, 
    
    selectSlide: function(slide) {        
        if(slide == this.slideShown) return;
        this.showSlide(slide);
    },

    showSlide: function(slide) {
        this.slideShown = slide;
        var element = $('slide' + this.slideShown);
        var parent = $('slides');
        element.setStyle({ display : 'none' });
        parent.removeChild(element);
        parent.appendChild(element);
        Effect.Appear('slide' + this.slideShown, { duration: 0.2});            
    },   
    
    moveToNextSlide: function(self) {      
        self.slideShown = (self.slideShown + 1) % self.numSlides;   
        self.listSwitch.switchTo('showSlide'+self.slideShown);
        self.showSlide(self.slideShown);
    }
});