// The Sliding Tabs mootools plugin is a creation of Jenna “Blueberry” Fox!
// This isn't free software, so don't forget to give me a gift of some sort!
// some idea's include poetry, drawings, songs, doodads, whosits, fuzzy things,
// software licenses, and general free stuff. Contact me at http://creativepony.com/#contact
// and let me know where you're using Sliding Tabs!
// 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);