/**
 *
 * Sometimes you want to show several screens worth of information but you've only got a small screen to work with.
 * TabPanels and Carousels both enable you to see one screen of many at a time, and underneath they both use a Card
 * Layout.
 *
 * Card Layout takes the size of the Container it is applied to and sizes the currently active item to fill the
 * Container completely. It then hides the rest of the items, allowing you to change which one is currently visible but
 * only showing one at once:
 *
 * {@img ../guides/layouts/card.jpg}
 *
 *
 * Here the gray box is our Container, and the blue box inside it is the currently active card. The three other cards
 * are hidden from view, but can be swapped in later. While it's not too common to create Card layouts directly, you
 * can do so like this:
 *
 *     var panel = Ext.create('Ext.Panel', {
 *         layout: 'card',
 *         items: [
 *             {
 *                 html: "First Item"
 *             },
 *             {
 *                 html: "Second Item"
 *             },
 *             {
 *                 html: "Third Item"
 *             },
 *             {
 *                 html: "Fourth Item"
 *             }
 *         ]
 *     });
 *
 *     panel.getLayout().{@link Ext.Container#setActiveItem setActiveItem}(1);
 *
 * Here we create a Panel with a Card Layout and later set the second item active (the active item index is zero-based,
 * so 1 corresponds to the second item). Normally you're better off using a {@link Ext.tab.Panel tab panel} or a
 * {@link Ext.carousel.Carousel carousel}.
 *
 * For a more detailed overview of what layouts are and the types of layouts shipped with Sencha Touch 2, check out the
 * [Layout Guide](#!/guide/layouts).
 */
Ext.define('Ext.layout.Card', {
    extend: 'Ext.layout.Fit',
    alternateClassName: 'Ext.layout.CardLayout',

    requires: [
        'Ext.fx.layout.Card'
    ],

    alias: 'layout.card',

    cls: Ext.baseCSSPrefix + 'layout-card',

    itemCls: Ext.baseCSSPrefix + 'layout-card-item',

    config: {
        /**
         * @cfg {Ext.fx.layout.Card} animation Card animation configuration
         * Controls how card transitions are animated
         * @accessor
         */
        animation: null
    },

    /**
     * @private
     */
    applyAnimation: function(animation) {
        return new Ext.fx.layout.Card(animation);
    },

    /**
     * @private
     */
    updateAnimation: function(animation, oldAnimation) {
        animation.setLayout(this);

        if (oldAnimation) {
            oldAnimation.destroy();
        }
    },

    /**
     * @private
     */
    doItemAdd: function(item, index) {
        if (item.isInnerItem()) {
            item.addCls(this.itemCls);
            item.hide();
        }

        this.callParent(arguments);
    },

    /**
     * @private
     */
    doItemRemove: function(item) {
        if (item.isInnerItem()) {
            item.removeCls(this.itemCls);
            item.show();
        }

        this.callParent(arguments);
    },

    /**
     * @private
     */
    onActiveItemChange: function(newActiveItem, oldActiveItem) {
        this.fireAction(this.eventNames.activeItemChange, [newActiveItem, oldActiveItem],
            this.doActiveItemChange);
    },

    /**
     * @private
     */
    doActiveItemChange: function(newActiveItem, oldActiveItem) {
        if (oldActiveItem) {
            oldActiveItem.hide();
        }

        if (newActiveItem) {
            newActiveItem.show();
        }
    }
});