    /**
     * This class functions **between siblings of a {@link Ext.layout.container.VBox VBox} or {@link Ext.layout.container.HBox HBox}
     * layout** to resize both immediate siblings.
     *
     * A Splitter will preserve the flex ratio of any flexed siblings it is required to resize. It does this by setting the `flex` property of *all* flexed siblings
     * to equal their pixel size. The actual numerical `flex` property in the Components will change, but the **ratio** to the total flex value will be preserved.
     *
     * A Splitter may be configured to show a centered mini-collapse tool orientated to collapse the {@link #collapseTarget}.
     * The Splitter will then call that sibling Panel's {@link Ext.panel.Panel#method-collapse collapse} or {@link Ext.panel.Panel#method-expand expand} method
     * to perform the appropriate operation (depending on the sibling collapse state). To create the mini-collapse tool but take care
     * of collapsing yourself, configure the splitter with `{@link #performCollapse}: false`.
     */
    Ext.define('Ext.resizer.Splitter', {
        extend: 'Ext.Component',
        requires: ['Ext.XTemplate'],
        uses: ['Ext.resizer.SplitterTracker'],
        alias: 'widget.splitter',

        childEls: [
            'collapseEl'
        ],

        renderTpl: [
            '<tpl if="collapsible===true">',
                '<div id="{id}-collapseEl" class="', Ext.baseCSSPrefix, 'collapse-el ',
                    Ext.baseCSSPrefix, 'layout-split-{collapseDir}">&#160;</div>',
            '</tpl>'
        ],

        baseCls: Ext.baseCSSPrefix + 'splitter',
        collapsedClsInternal: Ext.baseCSSPrefix + 'splitter-collapsed',

        /**
         * @cfg {Boolean} collapsible
         * True to show a mini-collapse tool in the Splitter to toggle expand and collapse on the {@link #collapseTarget} Panel.
         * Defaults to the {@link Ext.panel.Panel#collapsible collapsible} setting of the Panel.
         */
        collapsible: false,

        /**
         * @cfg {Boolean} performCollapse
         * Set to false to prevent this Splitter's mini-collapse tool from managing the collapse
         * state of the {@link #collapseTarget}.
         */

        /**
         * @cfg {Boolean} collapseOnDblClick
         * True to enable dblclick to toggle expand and collapse on the {@link #collapseTarget} Panel.
         */
        collapseOnDblClick: true,

        /**
         * @cfg {Number} defaultSplitMin
         * Provides a default minimum width or height for the two components
         * that the splitter is between.
         */
        defaultSplitMin: 40,

        /**
         * @cfg {Number} defaultSplitMax
         * Provides a default maximum width or height for the two components
         * that the splitter is between.
         */
        defaultSplitMax: 1000,

        /**
         * @cfg {String} collapsedCls
         * A class to add to the splitter when it is collapsed. See {@link #collapsible}.
         */

        width: 5,
        height: 5,

        /**
         * @cfg {String/Ext.panel.Panel} collapseTarget
         * A string describing the relative position of the immediate sibling Panel to collapse. May be 'prev' or 'next'.
         *
         * Or the immediate sibling Panel to collapse.
         *
         * The orientation of the mini-collapse tool will be inferred from this setting.
         *
         * **Note that only Panels may be collapsed.**
         */
        collapseTarget: 'next',

        /**
         * @property {String} orientation
         * Orientation of this Splitter. `'vertical'` when used in an hbox layout, `'horizontal'`
         * when used in a vbox layout.
         */

        horizontal: false,
        vertical: false,

        /**
         * Returns the config object (with an `xclass` property) for the splitter tracker. This
         * is overridden by {@link Ext.resizer.BorderSplitter BorderSplitter} to create a
         * {@link Ext.resizer.BorderSplitterTracker BorderSplitterTracker}.
         * @protected
         */
        getTrackerConfig: function () {
            return {
                xclass: 'Ext.resizer.SplitterTracker',
                el: this.el,
                splitter: this
            };
        },

        beforeRender: function() {
            var me = this,
                target = me.getCollapseTarget(),
                collapseDir = me.getCollapseDirection();

            me.callParent();

            if (target.collapsed) {
                me.addCls(me.collapsedClsInternal);
            }

            me.addCls(me.baseCls + '-' + me.orientation);
            Ext.applyIf(me.renderData, {
                collapseDir: collapseDir,
                collapsible: me.collapsible || target.collapsible
            });
        },

        onRender: function() {
            var me = this;

            me.callParent(arguments);

            // Add listeners on the mini-collapse tool unless performCollapse is set to false
            if (me.performCollapse !== false) {
                if (me.renderData.collapsible) {
                    me.mon(me.collapseEl, 'click', me.toggleTargetCmp, me);
                }
                if (me.collapseOnDblClick) {
                    me.mon(me.el, 'dblclick', me.toggleTargetCmp, me);
                }
            }

            // Ensure the mini collapse icon is set to the correct direction when the target is collapsed/expanded by any means
            me.mon(me.getCollapseTarget(), {
                collapse: me.onTargetCollapse,
                expand: me.onTargetExpand,
                scope: me
            });

            me.el.unselectable();
            me.tracker = Ext.create(me.getTrackerConfig());

            // Relay the most important events to our owner (could open wider later):
            me.relayEvents(me.tracker, [ 'beforedragstart', 'dragstart', 'dragend' ]);
        },

        getCollapseDirection: function() {
            var me = this,
                dir = me.collapseDirection,
                collapseTarget, idx, items, type;

            if (!dir) {
                collapseTarget = me.collapseTarget;
                if (collapseTarget.isComponent) {
                    dir = collapseTarget.collapseDirection;
                }

                if (!dir) {
                    // Avoid duplication of string tests.
                    // Create a two bit truth table of the configuration of the Splitter:
                    // Collapse Target | orientation
                    //        0              0             = next, horizontal
                    //        0              1             = next, vertical
                    //        1              0             = prev, horizontal
                    //        1              1             = prev, vertical
                    type = me.ownerCt.layout.type;
                    if (collapseTarget.isComponent) {
                        items = me.ownerCt.items;
                        idx = Number(items.indexOf(collapseTarget) == items.indexOf(me) - 1) << 1 | Number(type == 'hbox');
                    } else {
                        idx = Number(me.collapseTarget == 'prev') << 1 | Number(type == 'hbox');
                    }

                    // Read the data out the truth table
                    dir = ['bottom', 'right', 'top', 'left'][idx];
                }

                me.collapseDirection = dir;
            }

            me.orientation = (dir == 'top' || dir == 'bottom') ? 'horizontal' : 'vertical';
            me[me.orientation] = true;

            return dir;
        },

        getCollapseTarget: function() {
            var me = this;

            return me.collapseTarget.isComponent ? me.collapseTarget : me.collapseTarget == 'prev' ? me.previousSibling() : me.nextSibling();
        },

        onTargetCollapse: function(target) {
            this.el.addCls([this.collapsedClsInternal, this.collapsedCls]);
        },

        onTargetExpand: function(target) {
            this.el.removeCls([this.collapsedClsInternal, this.collapsedCls]);
        },

        toggleTargetCmp: function(e, t) {
            var cmp = this.getCollapseTarget(),
                placeholder = cmp.placeholder,
                toggle;

            if (placeholder && !placeholder.hidden) {
                toggle = true;
            } else {
                toggle = !cmp.hidden;
            }

            if (toggle) {
                if (cmp.collapsed) {
                    cmp.expand();
                } else if (cmp.collapseDirection) {
                    cmp.collapse();
                } else {
                    cmp.collapse(this.renderData.collapseDir);
                }
            }
        },

        /*
         * Work around IE bug. %age margins do not get recalculated on element resize unless repaint called.
         */
        setSize: function() {
            var me = this;
            me.callParent(arguments);
            if (Ext.isIE && me.el) {
                me.el.repaint();
            }
        }
    });