    /**
     * @class Ext.layout.container.Anchor
     * @extends Ext.layout.container.Container
     *
     * This is a layout that enables anchoring of contained elements relative to the container's dimensions.
     * If the container is resized, all anchored items are automatically rerendered according to their
     * `{@link #anchor}` rules.
     *
     * This class is intended to be extended or created via the {@link Ext.container.AbstractContainer#layout layout}: 'anchor'
     * config, and should generally not need to be created directly via the new keyword.
     *
     * AnchorLayout does not have any direct config options (other than inherited ones). By default,
     * AnchorLayout will calculate anchor measurements based on the size of the container itself. However, the
     * container using the AnchorLayout can supply an anchoring-specific config property of `anchorSize`.
     *
     * If anchorSize is specifed, the layout will use it as a virtual container for the purposes of calculating
     * anchor measurements based on it instead, allowing the container to be sized independently of the anchoring
     * logic if necessary.
     *
     *     @example
     *     Ext.create('Ext.Panel', {
     *         width: 500,
     *         height: 400,
     *         title: "AnchorLayout Panel",
     *         layout: 'anchor',
     *         renderTo: Ext.getBody(),
     *         items: [
     *             {
     *                 xtype: 'panel',
     *                 title: '75% Width and 20% Height',
     *                 anchor: '75% 20%'
     *             },
     *             {
     *                 xtype: 'panel',
     *                 title: 'Offset -300 Width & -200 Height',
     *                 anchor: '-300 -200'
     *             },
     *             {
     *                 xtype: 'panel',
     *                 title: 'Mixed Offset and Percent',
     *                 anchor: '-250 20%'
     *             }
     *         ]
     *     });
     */
    Ext.define('Ext.layout.container.Anchor', {

        /* Begin Definitions */

        alias: 'layout.anchor',
        extend: 'Ext.layout.container.Container',
        alternateClassName: 'Ext.layout.AnchorLayout',

        /* End Definitions */

        /**
         * @cfg {String} anchor
         *
         * This configuation option is to be applied to **child `items`** of a container managed by
         * this layout (ie. configured with `layout:'anchor'`).
         *
         * This value is what tells the layout how an item should be anchored to the container. `items`
         * added to an AnchorLayout accept an anchoring-specific config property of **anchor** which is a string
         * containing two values: the horizontal anchor value and the vertical anchor value (for example, '100% 50%').
         * The following types of anchor values are supported:
         *
         * - **Percentage** : Any value between 1 and 100, expressed as a percentage.
         *
         *   The first anchor is the percentage width that the item should take up within the container, and the
         *   second is the percentage height.  For example:
         *
         *       // two values specified
         *       anchor: '100% 50%' // render item complete width of the container and
         *                          // 1/2 height of the container
         *       // one value specified
         *       anchor: '100%'     // the width value; the height will default to auto
         *
         * - **Offsets** : Any positive or negative integer value.
         *
         *   This is a raw adjustment where the first anchor is the offset from the right edge of the container,
         *   and the second is the offset from the bottom edge. For example:
         *
         *       // two values specified
         *       anchor: '-50 -100' // render item the complete width of the container
         *                          // minus 50 pixels and
         *                          // the complete height minus 100 pixels.
         *       // one value specified
         *       anchor: '-50'      // anchor value is assumed to be the right offset value
         *                          // bottom offset will default to 0
         *
         * - **Sides** : Valid values are `right` (or `r`) and `bottom` (or `b`).
         *
         *   Either the container must have a fixed size or an anchorSize config value defined at render time in
         *   order for these to have any effect.
         *
         * - **Mixed** :
         *
         *   Anchor values can also be mixed as needed.  For example, to render the width offset from the container
         *   right edge by 50 pixels and 75% of the container's height use:
         *
         *       anchor:   '-50 75%'
         */
        type: 'anchor',

        /**
         * @cfg {String} defaultAnchor
         * Default anchor for all child <b>container</b> items applied if no anchor or specific width is set on the child item.  Defaults to '100%'.
         */
        defaultAnchor: '100%',

        parseAnchorRE: /^(r|right|b|bottom)$/i,

        // private
        onLayout: function() {
            this.callParent(arguments);

            var me = this,
                size = me.getLayoutTargetSize(),
                owner = me.owner,
                target = me.getTarget(),
                ownerWidth = size.width,
                ownerHeight = size.height,
                overflow = target.getStyle('overflow'),
                components = me.getVisibleItems(owner),
                len = components.length,
                boxes = [],
                box, newTargetSize, component, anchorSpec, calcWidth, calcHeight,
                i, el, cleaner;

            if (ownerWidth < 20 && ownerHeight < 20) {
                return;
            }

            // Anchor layout uses natural HTML flow to arrange the child items.
            // To ensure that all browsers (I'm looking at you IE!) add the bottom margin of the last child to the
            // containing element height, we create a zero-sized element with style clear:both to force a "new line"
            if (!me.clearEl) {
                me.clearEl = target.createChild({
                    cls: Ext.baseCSSPrefix + 'clear',
                    role: 'presentation'
                });
            }

            // Work around WebKit RightMargin bug. We're going to inline-block all the children only ONCE and remove it when we're done
            if (!Ext.supports.RightMargin) {
                cleaner = Ext.Element.getRightMarginFixCleaner(target);
                target.addCls(Ext.baseCSSPrefix + 'inline-children');
            }

            for (i = 0; i < len; i++) {
                component = components[i];
                el = component.el;

                anchorSpec = component.anchorSpec;
                if (anchorSpec) {
                    if (anchorSpec.right) {
                        calcWidth = me.adjustWidthAnchor(anchorSpec.right(ownerWidth) - el.getMargin('lr'), component);
                    } else {
                        calcWidth = undefined;
                    }
                    if (anchorSpec.bottom) {
                        calcHeight = me.adjustHeightAnchor(anchorSpec.bottom(ownerHeight) - el.getMargin('tb'), component);
                    } else {
                        calcHeight = undefined;
                    }

                    boxes.push({
                        component: component,
                        anchor: true,
                        width: calcWidth || undefined,
                        height: calcHeight || undefined
                    });
                } else {
                    boxes.push({
                        component: component,
                        anchor: false
                    });
                }
            }

            // Work around WebKit RightMargin bug. We're going to inline-block all the children only ONCE and remove it when we're done
            if (!Ext.supports.RightMargin) {
                target.removeCls(Ext.baseCSSPrefix + 'inline-children');
                cleaner();
            }

            for (i = 0; i < len; i++) {
                box = boxes[i];
                me.setItemSize(box.component, box.width, box.height);
            }

            if (overflow && overflow != 'hidden' && !me.adjustmentPass) {
                newTargetSize = me.getLayoutTargetSize();
                if (newTargetSize.width != size.width || newTargetSize.height != size.height) {
                    me.adjustmentPass = true;
                    me.onLayout();
                }
            }

            delete me.adjustmentPass;
        },

        // private
        parseAnchor: function(a, start, cstart) {
            if (a && a != 'none') {
                var ratio;
                // standard anchor
                if (this.parseAnchorRE.test(a)) {
                    var diff = cstart - start;
                    return function(v) {
                        return v - diff;
                    };
                }
                // percentage
                else if (a.indexOf('%') != -1) {
                    ratio = parseFloat(a.replace('%', '')) * 0.01;
                    return function(v) {
                        return Math.floor(v * ratio);
                    };
                }
                // simple offset adjustment
                else {
                    a = parseInt(a, 10);
                    if (!isNaN(a)) {
                        return function(v) {
                            return v + a;
                        };
                    }
                }
            }
            return null;
        },

        // private
        adjustWidthAnchor: function(value, comp) {
            return value;
        },

        // private
        adjustHeightAnchor: function(value, comp) {
            return value;
        },

        configureItem: function(item) {
            var me = this,
                owner = me.owner,
                anchor= item.anchor,
                anchorsArray,
                anchorSpec,
                anchorWidth,
                anchorHeight;

            if (!item.anchor && item.items && !Ext.isNumber(item.width) && !(Ext.isIE6 && Ext.isStrict)) {
                item.anchor = anchor = me.defaultAnchor;
            }

            // find the container anchoring size
            if (owner.anchorSize) {
                if (typeof owner.anchorSize == 'number') {
                    anchorWidth = owner.anchorSize;
                }
                else {
                    anchorWidth = owner.anchorSize.width;
                    anchorHeight = owner.anchorSize.height;
                }
            }
            else {
                anchorWidth = owner.initialConfig.width;
                anchorHeight = owner.initialConfig.height;
            }

            if (anchor) {
                // cache all anchor values
                anchorsArray = anchor.split(' ');
                item.anchorSpec = anchorSpec = {
                    right: me.parseAnchor(anchorsArray[0], item.initialConfig.width, anchorWidth),
                    bottom: me.parseAnchor(anchorsArray[1], item.initialConfig.height, anchorHeight)
                };

                if (anchorSpec.right) {
                    item.layoutManagedWidth = 1;
                } else {
                    item.layoutManagedWidth = 2;
                }

                if (anchorSpec.bottom) {
                    item.layoutManagedHeight = 1;
                } else {
                    item.layoutManagedHeight = 2;
                }
            } else {
                item.layoutManagedWidth = 2;
                item.layoutManagedHeight = 2;
            }
            this.callParent(arguments);
        }

    });