// Documentation: http://creativepony.com/journal/scripts/sliding-tabs/
// version: 1.8


var SlidingTabs = new Class({options: {startingSlide: false, 
// sets the slide to start on, either an element or an id
activeButtonClass: 'active', 
// class to add to selected button
    activationEvent: 'click', 
// you can set this to ‘mouseover’ or whatever you like
wrap: true, 
// calls to previous() and next() should wrap around?
slideEffect: { // options for effect used to animate the sliding, see Fx.Base in mootools docs
duration: 400 // 0.4 of a second
    },
    animateHeight: true, 
// animate height of container
    rightOversized: 0 
// how much of the next pane to show to the right of the current pane
  },
  current: null, 
// zero based current pane number, read only
  buttons: false,
  outerSlidesBox: null,
  innerSlidesBox: null,
  panes: null,
  fx: null, 
// this one animates the scrolling inside
  heightFx: null, // this one animates the height

initialize: function(buttonContainer, slideContainer, options) 
{if (buttonContainer) { this.buttons = $(buttonContainer).getChildren(); }
this.outerSlidesBox = $(slideContainer);
this.innerSlidesBox = this.outerSlidesBox.getFirst();
this.panes = this.innerSlidesBox.getChildren();
this.setOptions(options);
this.fx = new Fx.Scroll(this.outerSlidesBox, this.options.slideEffect);
this.heightFx = this.outerSlidesBox.effect('height', this.options.slideEffect);
// set up button highlight
this.current = this.options.startingSlide ? this.panes.indexOf($(this.options.startingSlide)) : 0;
if (this.buttons) { this.buttons[this.current].addClass(this.options.activeButtonClass); }
// add needed stylings
    
this.outerSlidesBox.setStyle('overflow', 'hidden');
this.panes.each(function(pane, index) {pane.setStyles({'float': 'left','overflow': 'hidden' });}.bind(this));
// stupidness to make IE work - it boggles the mind why this has any effect
    
// maybe it's something to do with giving it layout?
this.innerSlidesBox.setStyle('float', 'left');
if (this.options.startingSlide) this.fx.toElement(this.options.startingSlide);
// add events to the buttons
    if (this.buttons) this.buttons.each( function(button) {button.addEvent(this.options.activationEvent, this.buttonEventHandler.bindWithEvent(this, button));
    }.bind(this));
if (this.options.animateHeight)
 this.heightFx.set(this.panes[this.current].offsetHeight);
// set up all the right widths inside the panes
    this.recalcWidths();
  },
 // to change to a specific tab, call this, argument is the pane element you want to switch to.
  
changeTo: function(element, animate) {
    if ($type(element) == 'number') element = this.panes[element - 1];
if (!$defined(animate)) animate = true;
var event = { cancel: false, target: $(element), animateChange: animate };
this.fireEvent('change', event);
    if (event.cancel == true) { return; };
if (this.buttons) { this.buttons[this.current].removeClass(this.options.activeButtonClass); };
 this.current = this.panes.indexOf($(event.target));
    if (this.buttons) { this.buttons[this.current].addClass(this.options.activeButtonClass); };
this.fx.stop();
    
if (event.animateChange) 
{ this.fx.toElement(event.target);} else {this.outerSlidesBox.scrollTo(this.current * this.outerSlidesBox.offsetWidth.toInt(), 0);}
 if (this.options.animateHeight)
 this.heightFx.start(this.panes[this.current].offsetHeight);
  },
// Handles a click
  buttonEventHandler: function(event, button) { if (event.target == this.buttons[this.current]) return;

this.changeTo(this.panes[this.buttons.indexOf($(button))]);
  },
  
  // call this to go to the next tab
  
next: function() {
    var next = this.current + 1;
    if (next == this.panes.length) 
{ if (this.options.wrap == true) { next = 0 } else { return }
    }
 this.changeTo(this.panes[next]);
  },
  
  
// to go to the previous tab
  previous: function() {var prev = this.current - 1
    
if (prev < 0) {if (this.options.wrap == true) { prev = this.panes.length - 1 } else { return }}
   this.changeTo(this.panes[prev]);
  },
  
  
// call this if the width of the sliding tabs container changes to get everything in line again
  
recalcWidths: function() { this.panes.each(function(pane, index) { pane.setStyle('width', this.outerSlidesBox.offsetWidth.toInt() - this.options.rightOversized + 'px');}.bind(this));
this.innerSlidesBox.setStyle('width', (this.outerSlidesBox.offsetWidth.toInt() * this.panes.length) + 'px'
    );
// fix positioning
    
if (this.current > 0) { this.fx.stop();
 this.outerSlidesBox.scrollTo(this.current * this.outerSlidesBox.offsetWidth.toInt(), 0); }}
});


SlidingTabs.implement(new Options, new Events);