/*
This file is part of Ext JS 4.2

Copyright (c) 2011-2013 Sencha Inc

Contact:  http://www.sencha.com/contact

Commercial Usage
Licensees holding valid commercial licenses may use this file in accordance with the Commercial
Software License Agreement provided with the Software or, alternatively, in accordance with the
terms contained in a written agreement between you and Sencha.

If you are unsure which license is appropriate for your use, please contact the sales department
at http://www.sencha.com/contact.

Build date: 2013-09-18 17:18:59 (940c324ac822b840618a3a8b2b4b873f83a1a9b1)
*/
/**
 * @class Ext.layout.container.Auto
 *
 * The AutoLayout is the default layout manager delegated by {@link Ext.container.Container} to
 * render any child Components when no `{@link Ext.container.Container#layout layout}` is configured into
 * a `{@link Ext.container.Container Container}.` AutoLayout provides only a passthrough of any layout calls
 * to any child containers.
 *
 *     @example
 *     Ext.create('Ext.Panel', {
 *         width: 500,
 *         height: 280,
 *         title: "AutoLayout Panel",
 *         layout: 'auto',
 *         renderTo: document.body,
 *         items: [{
 *             xtype: 'panel',
 *             title: 'Top Inner Panel',
 *             width: '75%',
 *             height: 90
 *         },
 *         {
 *             xtype: 'panel',
 *             title: 'Bottom Inner Panel',
 *             width: '75%',
 *             height: 90
 *         }]
 *     });
 */
Ext.define('Ext.layout.container.Auto', {

    /* Begin Definitions */

    alias: ['layout.auto', 'layout.autocontainer'],

    extend: 'Ext.layout.container.Container',

    /* End Definitions */

    type: 'autocontainer',

    childEls: [
        'outerCt',
        'innerCt',
        'clearEl'
    ],

    /**
     * @cfg {Boolean} [reserveScrollbar=false]
     * Set to `true` to leave space for a vertical scrollbar (if the OS shows space-consuming scrollbars) regardless
     * of whether a scrollbar is needed.
     *
     * This is useful if content height changes during application usage, but you do not want the calculated width
     * of child items to change when a scrollbar appears or disappears. The scrollbar will appear in the reserved space,
     * and the calculated width of child Components will not change.
     *
     *     @example
     *     Ext.define('Employee', {
     *         extend: 'Ext.data.Model',
     *         fields: [
     *            {name: 'rating', type: 'int'},
     *            {name: 'salary', type: 'float'},
     *            {name: 'name'}
     *         ]
     *     });
     *
     *     function createFakeData(count) {
     *         var firstNames   = ['Ed', 'Tommy', 'Aaron', 'Abe', 'Jamie', 'Adam', 'Dave', 'David', 'Jay', 'Nicolas', 'Nige'],
     *             lastNames    = ['Spencer', 'Maintz', 'Conran', 'Elias', 'Avins', 'Mishcon', 'Kaneda', 'Davis', 'Robinson', 'Ferrero', 'White'],
     *             ratings      = [1, 2, 3, 4, 5],
     *             salaries     = [100, 400, 900, 1500, 1000000];
     *
     *         var data = [];
     *         for (var i = 0; i < (count || 25); i++) {
     *             var ratingId    = Math.floor(Math.random() * ratings.length),
     *                 salaryId    = Math.floor(Math.random() * salaries.length),
     *                 firstNameId = Math.floor(Math.random() * firstNames.length),
     *                 lastNameId  = Math.floor(Math.random() * lastNames.length),
     *
     *                 rating      = ratings[ratingId],
     *                 salary      = salaries[salaryId],
     *                 name        = Ext.String.format("{0} {1}", firstNames[firstNameId], lastNames[lastNameId]);
     *
     *             data.push({
     *                 rating: rating,
     *                 salary: salary,
     *                 name: name
     *             });
     *         }
     *         store.loadData(data);
     *     }
     *
     *     // create the Data Store
     *     var store = Ext.create('Ext.data.Store', {
     *         id: 'store',
     *         model: 'Employee',
     *         proxy: {
     *             type: 'memory'
     *         }
     *     });
     *     createFakeData(10);
     *
     *     var grid = Ext.create('Ext.grid.Panel', {
     *         title: 'Grid loaded with varying number of records',
     *         anchor: '100%',
     *         store: store,
     *         columns: [{
     *             xtype: 'rownumberer',
     *             width: 40,
     *             sortable: false
     *         },{
     *             text: 'Name',
     *             flex: 1,
     *             sortable: true,
     *             dataIndex: 'name'
     *         },{
     *             text: 'Rating',
     *             width: 125,
     *             sortable: true,
     *             dataIndex: 'rating'
     *         },{
     *             text: 'Salary',
     *             width: 125,
     *             sortable: true,
     *             dataIndex: 'salary',
     *             align: 'right',
     *             renderer: Ext.util.Format.usMoney
     *         }]
     *     });
     *
     *     Ext.create('Ext.panel.Panel', {
     *         renderTo: document.body,
     *         width: 800,
     *         height: 600,
     *         layout: {
     *             type: 'anchor',
     *             reserveScrollbar: true // There will be a gap even when there's no scrollbar
     *         },
     *         autoScroll: true,
     *         items: grid,
     *         tbar: {
     *             defaults: {
     *                 handler: function(b) {
     *                     createFakeData(b.count);
     *                 }
     *             },
     *             items: [{
     *                  text: '10 Items',
     *                  count: 10
     *             },{
     *                  text: '100 Items',
     *                  count: 100
     *             },{
     *                  text: '300 Items',
     *                  count: 300
     *             },{
     *                  text: '1000 Items',
     *                  count: 1000
     *             },{
     *                  text: '5000 Items',
     *                  count: 5000
     *             }]
     *         }
     *     });
     *
     */
    reserveScrollbar: false,

    /**
     * @property {Boolean} [managePadding=true]
     * indicates that this layout will correct cross browser padding differences when the
     * container has overflow.
     * 
     * In some browsers the right and/or bottom padding of a container is lost when
     * the container has overflow.  If managePadding is true the layout will apply the
     * padding to an inner wrapping element instead of the container element that has the
     * overflow so that paddding will be included in the scrollable area.
     * Note: padding will not be managed if it is configured on the container using
     * a style config or css class.  In order to be managed, padding must be added to the
     * container using the appropriate {@link Ext.AbstractComponent#contentPaddingProperty
     * contentPaddingProperty}.  For {@link Ext.panel.Panel Panels} use 
     * {@link Ext.panel.AbstractPanel#bodyPadding}, and for
     * {@link Ext.container.Container Containers}, use
     * {@link Ext.AbstractComponent#padding padding}
     */
    managePadding: true,

    /**
     * @property {Boolean} [manageOverflow=false]
     * true to rerun the layout if scrollbars are needed.
     */
    manageOverflow: false,

    // Begin with no previous adjustments
    lastOverflowAdjust: {
        width: 0,
        height: 0
    },

    // Auto layout's renderTpl wraps the content in an outerCt which is used to accomplish
    // the following 3 goals:
    // 
    // 1. When the container has a shrink wrapped width and/or height, the outerCt is used
    // to measure the size of the content.
    // 2. When the container has overflow some browsers lose the container's right and/or
    // bottom padding.  To fix this, the padding is rendered to the outerCt instead of
    // the container target element.  This ensures that the padding is included in the 
    // container's scrollWidth/scrollHeight. In Old IE when a table is used, the padding
    // is rendered to the innerCt td element.
    // 3. The outerCt contains the margins of its children, that is to say, it prevents
    // them from collapsing.
    renderTpl: [
        '{% if (!(Ext.isIEQuirks || Ext.isIE7m)) { %}',
            // All browsers that support display:table use this template.
            // An outerCt with display:table shrink-wraps contents, and contains child
            // margins. The table-cell innerCt is required in order to support percentage
            // heights on child elements. Originally the outerCt started out as a div, but
            // was changed to a span to work around an obscure firefox 3.6 bug where
            // placing a Container inside of a fieldset's legend element causes the legend
            // to blow up if the outerCt is a div.
            '<span id="{ownerId}-outerCt" style="display:table;" role="presentation">',
                // height:100% is required on the innerCt in order for percentage-height
                // children to work in IE, firefox, and opera
                '<div id="{ownerId}-innerCt" style="display:table-cell;height:100%;',
                'vertical-align:top;{%this.renderPadding(out, values)%}" class="{innerCtCls}" role="presentation">',
                    '{%this.renderBody(out,values)%}',
                '</div>',
            '</span>',
        '{% } else if (values.shrinkWrapWidth) { %}',
            // If the containers width is shrink wrapped a table-based outerCt/innerCt
            // is required in old IE.  See getRenderData() for more details on the criteria
            // used to determine if the container has shrink wrapped width.
            '<table id="{ownerId}-outerCt" class="' + Ext.plainTableCls + '" role="presentation">',
                '<tbody role="presentation">',
                    '<tr role="presentation">',
                        '<td id="{ownerId}-innerCt" style="vertical-align:top;padding:0;',
                            '{%this.renderPadding(out, values)%}" class="{innerCtCls}" role="presentation">',
                            '{%this.renderBody(out,values)%}',
                             // clear element to contain the bottom margin of floated last child item
                            '<div id="{ownerId}-clearEl" class="', Ext.baseCSSPrefix,  'clear"',
                                'role="presentation"></div>',
                        '</td>',
                    '</tr>',
                '</tbody>',
            '</table>',
        '{% } else { %}',
            // If the container's width is not shrink wrapped, old IE can get by with
            // divs as the outerCt/innerCt.  zoom:1 is required to contain the margins
            // of children. The padding is placed on the outerCt instead of the innerCt.
            // This is to because if the padding was placed on the innerCt, the top
            // margin of the first child item would collapse into the top padding of
            // the innerCt.
            '<div id="{ownerId}-outerCt" style="zoom:1;{%this.renderPadding(out, values)%}" role="presentation">',
                '<div id="{ownerId}-innerCt" style="zoom:1;height:100%;" class="{innerCtCls}" role="presentation">',
                    '{%this.renderBody(out,values)%}',
                     // clear element to contain the bottom margin of floated last child item
                    '<div id="{ownerId}-clearEl" class="', Ext.baseCSSPrefix,  'clear"',
                        'role="presentation"></div>',
                '</div>',
            '</div>',
            // set a flag that indicates we are not using a "shrink wrap" template
            '{% values.$layout.isShrinkWrapTpl = false %}',
        '{% } %}'
    ],

    // This template is used for dynamically inserting a table outerCt/innerCt when needed.
    // It should be identical to the table template defined in renderTpl except that it
    // does not have renderBody or clearEl.  It is an empty shell so that the contents
    // of an already existing innerCt can be moved into it.
    tableTpl: [
        '<table id="{ownerId}-outerCt" class="' + Ext.plainTableCls + '" role="presentation">',
            '<tbody role="presentation">',
                '<tr role="presentation">',
                    '<td id="{ownerId}-innerCt" style="vertical-align:top;padding:0;',
                        '{%this.renderPadding(out, values)%}" class="{innerCtCls}" role="presentation">',
                    '</td>',
                '</tr>',
            '</tbody>',
        '</table>'
    ],

    isShrinkWrapTpl: true,


    beginLayout: function(ownerContext) {
        var me = this,
            bottomPadding, overflowYStyle, overflowXStyle, needsTable;
        
        me.callParent(arguments);

        me.initContextItems(ownerContext);

        if (!me.isShrinkWrapTpl) {
            // In most cases the determination to use a table based template is made at
            // render time; however, if the initial determination was incorrect, we may
            // need to dynamically replace the existing outerCt/innerCt with a table
            // (see insertTableCt)
            if (ownerContext.widthModel.shrinkWrap) {
                needsTable = true;
            }

            // in IE7 strict right padding is lost when there is horizontal overflow
            // unless the outerCt is a table.
            if (Ext.isStrict && Ext.isIE7) {
                overflowXStyle = me.getOverflowXStyle(ownerContext);
                if ((overflowXStyle === 'auto' || overflowXStyle === 'scroll') &&
                    ownerContext.paddingContext.getPaddingInfo().right) {
                    needsTable = true;
                }
            }

            if (needsTable) {
                me.insertTableCt(ownerContext);
            }
        }

        // When using the non-table renderTpl IE7 strict loses bottom padding if there
        // is vertical overflow. To adjust for the loss of padding, we add the bottom
        // padding to the height of the clearEl
        if (!me.isShrinkWrapTpl && Ext.isIE7 && Ext.isStrict && !me.clearElHasPadding) {
             bottomPadding = ownerContext.paddingContext.getPaddingInfo().bottom;
             overflowYStyle = me.getOverflowYStyle(ownerContext);
             if (bottomPadding && (overflowYStyle === 'auto' || overflowYStyle === 'scroll')) {
                 me.clearEl.setStyle('height', bottomPadding);
                 me.clearElHasPadding = true;
             }
        }
    },
    
    beforeLayoutCycle: function(ownerContext){
        var comp = this.owner,
            hierarchyState = comp.hierarchyState,
            hierarchyStateInner = comp.hierarchyStateInner;

        if (!hierarchyState || hierarchyState.invalid) {
            hierarchyState = comp.getHierarchyState(); // fixes both
            hierarchyStateInner = comp.hierarchyStateInner;
        }
        if (ownerContext.widthModel.shrinkWrap && this.isShrinkWrapTpl) {
            hierarchyStateInner.inShrinkWrapTable = true;
        } else {
            delete hierarchyStateInner.inShrinkWrapTable;
        }
    },

    beginLayoutCycle: function(ownerContext) {
        var me = this,
            outerCt = me.outerCt,
            lastOuterCtWidth = me.lastOuterCtWidth || '',
            lastOuterCtHeight = me.lastOuterCtHeight || '',
            lastOuterCtTableLayout = me.lastOuterCtTableLayout || '',
            state = ownerContext.state,
            overflowXStyle, overflowYStyle, outerCtWidth, outerCtHeight, outerCtTableLayout,
            deferWidth, hierarchyStateInner;

        me.callParent(arguments);

        // Default to "shrink wrap styles".
        outerCtWidth = outerCtHeight = outerCtTableLayout = '';

        if (!ownerContext.widthModel.shrinkWrap && me.isShrinkWrapTpl) {
            // if we're not shrink wrapping width, but we're using a shrink wrap template
            // we need to get the innerCt out of the way to avoid any shrink wrapping
            // effect on child items
            if (Ext.isIE7m && Ext.isStrict) {
                overflowYStyle = me.getOverflowYStyle(ownerContext);
                if (overflowYStyle === 'auto' || overflowYStyle === 'scroll') {
                    // IE6/7 strict will have the outerCt's width set by setCtSizeIfNeeded()
                    // when the container has potential vertical overflow, so there is
                    // no need to set the outerCt's width to 100% here
                    deferWidth = true;
                }
            }

            if (!deferWidth) {
                // fill the available width within the container
                outerCtWidth = '100%';
            }
            hierarchyStateInner = me.owner.hierarchyStateInner;
            // expand no further than the available width, even if contents are wider
            // unless there is a potential for horizontal overflow, then allow
            // the outerCt to expand to the width of the contents
            overflowXStyle = me.getOverflowXStyle(ownerContext);
            outerCtTableLayout = (hierarchyStateInner.inShrinkWrapTable ||
                                  overflowXStyle === 'auto' || 
                                  overflowXStyle === 'scroll') ? '' : 'fixed';
        }

        if (!ownerContext.heightModel.shrinkWrap && 
            !Ext.supports.PercentageHeightOverflowBug) {
            // if we're not shrink wrapping height, we need to get the outerCt out of the
            // way so that percentage height children will be sized correctly.  We do this
            // by giving the outerCt a height of '100%' unless the browser is affected by
            // the "percentage height overflow bug", in which case the outerCt will get a
            // pixel height set during the calculate phase after we know the targetEl size.
            outerCtHeight = '100%';
        }

        // if the outerCt width changed since last time (becuase of a widthModel change)
        // or if we set a pixel width on the outerCt last time to work around a browser-
        // specific bug, we need to set the width of the outerCt
        if ((outerCtWidth !== lastOuterCtWidth) || me.hasOuterCtPxWidth) {
            outerCt.setStyle('width', outerCtWidth);
            me.lastOuterCtWidth = outerCtWidth;
            me.hasOuterCtPxWidth = false;
        }

        // Set the outerCt table-layout property if different from last time.
        if (outerCtTableLayout !== lastOuterCtTableLayout) {
            outerCt.setStyle('table-layout', outerCtTableLayout);
            me.lastOuterCtTableLayout = outerCtTableLayout;
        }

        // if the outerCt height changed since last time (becuase of a heightModel change)
        // or if we set a pixel height on the outerCt last time to work around a browser-
        // specific bug, we need to set the height of the outerCt
        if ((outerCtHeight !== lastOuterCtHeight) || me.hasOuterCtPxHeight) {
            outerCt.setStyle('height', outerCtHeight);
            me.lastOuterCtHeight = outerCtHeight;
            me.hasOuterCtPxHeight = false;
        }

        if (me.hasInnerCtPxHeight) {
            me.innerCt.setStyle('height', '');
            me.hasInnerCtPxHeight = false;
        }

        // Begin with the scrollbar adjustment that we used last time - this is more likely
        // to be correct than beginning with no adjustment at all, but only if it is not
        // already defined - it may have already been set by invalidate()
        state.overflowAdjust = state.overflowAdjust || me.lastOverflowAdjust;
    },

    calculate: function(ownerContext) {
        var me = this,
            state = ownerContext.state,
            containerSize = me.getContainerSize(ownerContext, true),
            // If subclass has a calculateItems method, call it and cache the result
            calculatedItems = state.calculatedItems ||
                (state.calculatedItems = me.calculateItems ?
                me.calculateItems(ownerContext, containerSize) : true);

        me.setCtSizeIfNeeded(ownerContext, containerSize);

        if (calculatedItems && ownerContext.hasDomProp('containerChildrenSizeDone')) {

            me.calculateContentSize(ownerContext);

            if (containerSize.gotAll) {
                if (me.manageOverflow && !ownerContext.state.secondPass && !me.reserveScrollbar) {
                    me.calculateOverflow(ownerContext, containerSize);
                }
                return;
            }
        }
        
        me.done = false;
    },

    calculateContentSize: function (ownerContext) {
        var me = this,
            containerDimensions = ((ownerContext.widthModel.shrinkWrap ? 1 : 0) |
                                   (ownerContext.heightModel.shrinkWrap ? 2 : 0)),
            calcWidth = (containerDimensions & 1) || undefined,
            calcHeight = (containerDimensions & 2) || undefined,
            needed = 0,
            props = ownerContext.props;

        if (calcWidth) {
            if (isNaN(props.contentWidth)) {
                ++needed;
            } else {
                calcWidth = undefined;
            }
        }
        if (calcHeight) {
            if (isNaN(props.contentHeight)) {
                ++needed;
            } else {
                calcHeight = undefined;
            }
        }

        if (needed) {
            if (calcWidth && !ownerContext.setContentWidth(me.measureContentWidth(ownerContext))) {
                me.done = false;
            }
            if (calcHeight && !ownerContext.setContentHeight(me.measureContentHeight(ownerContext))) {
                me.done = false;
            }

            //if (me.done) {
            //    var el = ownerContext.targetContext.el.dom;
            //    Ext.log(this.owner.id, '.contentSize: ', contentWidth, 'x', contentHeight,
            //        ' => scrollSize: ', el.scrollWidth, 'x', el.scrollHeight);
            //}
        }
    },

    /**
     * Handles overflow processing for a container.  In addition to the ownerContext
     * passed to the {@link #calculate} method, this method also needs the containerSize
     * (the object returned by {@link #getContainerSize}).
     * @protected
     * 
     * @param {Ext.layout.ContextItem} ownerContext
     */
    calculateOverflow: function (ownerContext) {
        var me = this,
            width, height, scrollbarSize, scrollbars, xauto, yauto, targetEl;

        // Determine the dimensions that have overflow:auto applied. If these come by
        // way of component config, this does not require a DOM read:
        xauto = (me.getOverflowXStyle(ownerContext) === 'auto');
        yauto = (me.getOverflowYStyle(ownerContext) === 'auto');

        if (xauto || yauto) {
            scrollbarSize = Ext.getScrollbarSize();
            targetEl = ownerContext.overflowContext.el.dom;
            scrollbars = 0;

            if (targetEl.scrollWidth > targetEl.clientWidth) {
                // has horizontal scrollbar
                scrollbars |= 1;
            }

            if (targetEl.scrollHeight > targetEl.clientHeight) {
                // has vertical scrollbar
                scrollbars |= 2;
            }

            width = (yauto && (scrollbars & 2)) ? scrollbarSize.width : 0;
            height = (xauto && (scrollbars & 1)) ? scrollbarSize.height : 0;

            if (width !== me.lastOverflowAdjust.width || height !== me.lastOverflowAdjust.height) {
                me.done = false;

                // we pass overflowAdjust and overflowState in as state for the next
                // cycle (these are discarded if one of our ownerCt's invalidates):
                ownerContext.invalidate({
                    state: {
                        overflowAdjust: {
                            width: width,
                            height: height
                        },
                        overflowState: scrollbars,
                        secondPass: true
                    }
                });
            }
        }
    },

    completeLayout: function(ownerContext) {
       this.lastOverflowAdjust = ownerContext.state.overflowAdjust;
    },

    doRenderPadding: function(out, renderData) {
        // Careful! This method is bolted on to the renderTpl so all we get for context is
        // the renderData! The "this" pointer is the renderTpl instance!

        var me = renderData.$layout,
            owner = renderData.$layout.owner,
            padding = owner[owner.contentPaddingProperty];

        if (me.managePadding && padding) {
            out.push('padding:', owner.unitizeBox(padding));
        }
    },

    finishedLayout: function (ownerContext) {
        var innerCt = this.innerCt;

        this.callParent(arguments);

        if (Ext.isIEQuirks || Ext.isIE8m)  {
            // IE6/7/quirks need a repaint to fix various rendering issues. TODO: narrow
            // down the specific issues that require a repaint.
            // IE8 strict needs a repaint to render percentage sized child items.
            innerCt.repaint();
        }

        if (Ext.isOpera) {
            // Opera also needs a repaint to render percentage sized child items. but 
            // the normal repaint() method doesn't seem to do the trick, but tweaking
            // the position property in combination with reading scrollWidth does.
            innerCt.setStyle('position', 'relative');
            innerCt.dom.scrollWidth;
            innerCt.setStyle('position', '');
        }
    },

    /**
     * Returns the container size (that of the target). Only the fixed-sized dimensions can
     * be returned because the shrinkWrap dimensions are based on the contentWidth/Height
     * as determined by the container layout.
     *
     * If the {@link #calculateOverflow} method is used and if {@link #manageOverflow} is
     * true, this will adjust the width/height by the size of scrollbars.
     * 
     * @param {Ext.layout.ContextItem} ownerContext The owner's context item.
     * @param {Boolean} [inDom=false] True if the container size must be in the DOM.
     * @return {Object} The size
     * @return {Number} return.width The width
     * @return {Number} return.height The height
     * @protected
     */
    getContainerSize : function(ownerContext, inDom) {
        // Subtle But Important:
        // 
        // We don't want to call getProp/hasProp et.al. unless we in fact need that value
        // for our results! If we call it and don't need it, the layout manager will think
        // we depend on it and will schedule us again should it change.
        
        var size = this.callParent(arguments),
            overflowAdjust = ownerContext.state.overflowAdjust;

        if (overflowAdjust) {
            size.width -= overflowAdjust.width;
            size.height -= overflowAdjust.height;
        }

        return size;
    },

    getRenderData: function() {
        var owner = this.owner,
            data = this.callParent();
        
        // The shrinkWrapWidth data property is used by the renderTpl to determine if
        // a table-based outerCt/innerCt is required in old IE.  There are currently 2
        // container configs that turn on the table at render time:
        // 
        // 1. shrinkWrap:[1/3/true] on the container's initial config.  There
        // are two reasons one would want to use this config:
        //     a) If the container's width is initially shrink wrapped.
        //     b) If the container is not initially shrink wrapped and it is known
        //        at creation time that it will be shrink wrapped at some point
        //        after the initial layout cycle, then it is recommended to
        //        use the shrinkWrap config to initially configure the container
        //        with shrink wrapped width so that the layout does not have to
        //        dynamically insert a table after initial render.
        //        
        // 2. If the container's "floating" config is set to true, and the container
        // does not have a configured width, we can be relatively certain at render
        // time that the container will be shrink wrapped at layout time, so 
        // we go ahead and initially render using a table.
        if ((Ext.isIEQuirks || Ext.isIE7m) && // old IE
            ((owner.shrinkWrap & 1) || // shrink wrap width (handles value of 1, 3, or true)
            (owner.floating && !owner.width))) { // floating container with no configured width
            data.shrinkWrapWidth = true;
        }

        return data;
    },

    // Overridden method from Ext.layout.container.Container.
    // Used in the beforeLayout method to render all items into.
    getRenderTarget: function() {
        return this.innerCt;
    },

    // Overridden method from Ext.layout.container.Container.
    // Used by Container classes to insert special DOM elements which must exist in addition to the child components
    getElementTarget: function() {
        return this.innerCt;
    },

    /**
     * Returns the overflow-x style of the render target.
     * Note: If overflow is configured on a container using style or css class this method
     * will read the dom the first time it is called. It is therefore preferable for
     * performance reasons to use the autoScroll or overflowX config when horizontal
     * overflow is desired.
     * @protected
     * @param {Ext.layout.ContextItem} ownerContext
     * @return {String}
     */
    getOverflowXStyle: function(ownerContext) {
        return ownerContext.overflowXStyle ||
            (ownerContext.overflowXStyle = this.owner.scrollFlags.overflowX || ownerContext.overflowContext.getStyle('overflow-x'));
    },

    /**
     * Returns the overflow-y style of the render target.
     * Note: If overflow is configured on a container using style or css class this method
     * will read the dom the first time it is called. It is therefore preferable for
     * performance reasons to use the autoScroll or overflowY config when vertical
     * overflow is desired.
     * @protected
     * @param {Ext.layout.ContextItem} ownerContext
     * @return {String}
     */
    getOverflowYStyle: function(ownerContext) {
        return ownerContext.overflowYStyle || 
            (ownerContext.overflowYStyle = this.owner.scrollFlags.overflowY || ownerContext.overflowContext.getStyle('overflow-y'));
    },

    initContextItems: function(ownerContext) {
        var me = this,
            target = ownerContext.target,
            customOverflowEl = me.owner.customOverflowEl;

        ownerContext.outerCtContext = ownerContext.getEl('outerCt', me);
        ownerContext.innerCtContext = ownerContext.getEl('innerCt', me);
        
        if (customOverflowEl) {
            ownerContext.overflowContext = ownerContext.getEl(customOverflowEl);    
        } else {
            ownerContext.overflowContext = ownerContext.targetContext;
        }
        
        if (target[target.contentPaddingProperty] !== undefined) {
            // If padding was defined using the contentPaddingProperty, we render the
            // the padding to the innerCt or outerCt (depending on the template that is
            // being used), so we need to set the paddingContext accordingly.
            // Otherwise we leave paddingContext as set by Container layout (defaults to
            // the targetContext)
            ownerContext.paddingContext = me.isShrinkWrapTpl ?
                ownerContext.innerCtContext : ownerContext.outerCtContext;
        }
    },

    initLayout: function() {
        var me = this,
            scrollbarWidth = Ext.getScrollbarSize().width,
            owner = me.owner;

        me.callParent();

        // Create a default lastOverflowAdjust based upon scrolling configuration.
        // If the Container is to overflow, or we *always* reserve space for a scrollbar
        // then reserve space for a vertical scrollbar
        if (scrollbarWidth && me.manageOverflow && !me.hasOwnProperty('lastOverflowAdjust')) {
            if (owner.autoScroll || me.reserveScrollbar) {
                me.lastOverflowAdjust = {
                    width: scrollbarWidth,
                    height: 0
                };
            }
        }
    },

    /**
     * In some cases a table-based outerCt/innerCt is required in old IE (see renderTpl).
     * Most of the time this is determined at render time, however its possible that
     * we made the wrong determination at render time and now that the layout is in
     * progress we need a table.  If so, this method should be called to replace the
     * existing outerCt with a new table outerCt, and move the child elements to the new
     * innerCt.
     * @private
     */
    insertTableCt: function(ownerContext) {
        var me = this,
            owner = me.owner,
            i = 0,
            renderTpl, fragment, childNodes, childLength, targetEl;

        // get the table-based renderTpl
        renderTpl = Ext.XTemplate.getTpl(this, 'tableTpl');
        renderTpl.renderPadding = me.doRenderPadding;

        // To avoid unnecessary reflows, remove the innerCt from the dom
        // before operating on its children.
        me.outerCt.dom.removeChild(me.innerCt.dom);
        // create a document fragment to move all the childNodes to, so that
        // they can be batch appended to the new innerCt
        fragment = document.createDocumentFragment();
        childNodes = me.innerCt.dom.childNodes;
        childLength = childNodes.length;
        // append all the children to the document fragment
        for (; i < childLength; i++) {
            fragment.appendChild(childNodes[0]);
        }
        // process the table template and insert it into the target el
        targetEl = me.getTarget();
        targetEl.dom.innerHTML = renderTpl.apply({
            $layout: me,
            ownerId: me.owner.id
        });

        // append the document fragment containing the childNodes to the new innerCt
        targetEl.down('td').dom.appendChild(fragment);
        // reconfigure childEls to point to the new template's elements
        // we need to do this after the childNodes are appended to the new innerCt
        // because the clearEl is one of the childNodes
        me.applyChildEls(owner.el, owner.id)
        // set the flag that indicates we are using a "shrink wrap" template.
        // this needs to be done before reinitializeing the context items so that
        // the paddingContext will be configured correctly.
        me.isShrinkWrapTpl = true;
        // since we have new childEls we need to reinitialize the context items
        ownerContext.removeEl(me.outerCt);
        ownerContext.removeEl(me.innerCt);
        me.initContextItems(ownerContext);
    },

    measureContentHeight: function (ownerContext) {
        // contentHeight includes padding, but not border, framing or margins
        var contentHeight = this.outerCt.getHeight(),
            target = ownerContext.target;

        if (this.managePadding && (target[target.contentPaddingProperty] === undefined)) {
            // if padding was not configured using the appropriate contentPaddingProperty
            // then the padding will not be on the paddingContext, and therfore not included
            // in the outerCt measurement, so we need to read the padding from the
            // targetContext
            contentHeight += ownerContext.targetContext.getPaddingInfo().height;
        }
        return contentHeight;
    },

    measureContentWidth: function (ownerContext) {
        var dom, style, old, contentWidth, target;
            
        // In the newer Chrome versions, it won't measure the
        // width correctly without repainting the inner
        // cell in some circumstances.
        if (this.chromeCellMeasureBug) {
            dom = this.innerCt.dom;
            style = dom.style;
            old = style.display;
            
            if (old == 'table-cell') {
                style.display = '';
                dom.offsetWidth;
                style.display = old;
            }    
        }
        
        // contentWidth includes padding, but not border, framing or margins
        contentWidth = this.outerCt.getWidth();
        target = ownerContext.target;

        if (this.managePadding && (target[target.contentPaddingProperty] === undefined)) {
            // if padding was not configured using the appropriate contentPaddingProperty
            // then the padding will not be on the paddingContext, and therfore not included
            // in the outerCt measurement, so we need to read the padding from the
            // targetContext
            contentWidth += ownerContext.targetContext.getPaddingInfo().width;
        }
        return contentWidth;
    },

    /**
     * This method sets the height and/or width of the outerCt/innerCt to adjust for the
     * following browser-specific issues:
     * 
     * 1. In IE6 and 7 strict if we are using the shrink wrap template, and the outerCt
     * has a 100% width (because the container is not shrink wrapping width currently),
     * and the target element has a vertical scrollbar, the browser disregards the 
     * scrollbar when sizing the width of the outerCt.  This can result in the target
     * element gaining a horizontal scrollbar.  We fix this issue by setting a pixel
     * width on the outerCt
     * 
     * 2. In IE quirks when using the "non shrink wrap" template, a long non-breaking word
     * can cause the outerCt's width to expand beyond the width of its container. This 
     * behavior is desired if the container has the potential for horizontal overflow,
     * but can cause text to be hidden if the container's overflow is hidden. To prevent
     * this from happening we give the outerCt a fixed width in IE quirks when the
     * container does not have horizontal overflow.
     * 
     * 3. In some browsers a percentage-height element ignores the horizontal scrollbar
     * of its parent (see Ext.supports.PercentageHeightOverflowBug).  If the browser is
     * affected by this bug the outerCt needs a pixel height in order to support
     * percentage-height children when not shrink-wrapping height. If the browser is not
     * affected by this bug, a height of 100% is assigned to the outerCt (see
     * beginLayoutCycle).
     * 
     * 4. In IE6/7 strict when using the "shrink wrap" template, percentage heights on 
     * children do not work unless the innerCt td has a height set.  We can't use height
     * 100% on the innerCt because conent-box sizing will cause any top/bottom padding to
     * be added to the height.  The solution is to set a pixel height on the innerCt.
 
     * 5. IE8 strict mode has a bug with percentage height children.  if the innerCt has
     * a height of 100%, has padding, and has a child item with a percentage height, that
     * child item will be sized as a percentage of the parent's height plus padding height.
     * In other words, a child with height:50% would have its height caclulated thusly:
     * (parentHeight + parentPaddingHeight) * 0.5
     * To fix this, we have to give the innerCt a pixel height.
     * 
     * 6. In IE7 strict if we're using the "non shrink wrap" template, and the target
     * element has overflow-y:auto, the outerCt reserves space for the target element's
     * vertical scrollbar even when there is no vertical scrollbar.  This is fixed by
     * setting the targetEl's overflow property to "hidden" and then back to "auto".
     * 
     * @protected
     * @param {Ext.layout.ContextItem} ownerContext
     * @param {Object} containerSize
     */
    setCtSizeIfNeeded: function(ownerContext, containerSize) {
        var me = this,
            width = containerSize.width,
            height = containerSize.height,
            padding = ownerContext.paddingContext.getPaddingInfo(),
            targetEl = me.getTarget(),
            overflowXStyle = me.getOverflowXStyle(ownerContext),
            overflowYStyle = me.getOverflowYStyle(ownerContext),
            canOverflowX = (overflowXStyle === 'auto' || overflowXStyle === 'scroll'),
            canOverflowY = (overflowYStyle === 'auto' || overflowYStyle === 'scroll'),
            scrollbarSize = Ext.getScrollbarSize(),
            isShrinkWrapTpl = me.isShrinkWrapTpl,
            manageOverflow = me.manageOverflow,
            overflowStyleName, needsOuterHeight, needsInnerHeight, needsInnerCtPaddingHeight;

        if (width && !ownerContext.widthModel.shrinkWrap &&
            // shrink wrap outerCt needs pixel width in IE6/7 strict because 100% width
            // on the outerCt causes it to overlap the vertical scrollbar
            ((Ext.isIE7m && Ext.isStrict && isShrinkWrapTpl && canOverflowY) ||
            // non shrink wrap tpl outerCt in IE quirks needs pixel width to prevent
            // non-breaking text from causing the outerCt to expand beyond the width
            // of its container.
            (Ext.isIEQuirks && !isShrinkWrapTpl && !canOverflowX))) {

            if (!manageOverflow) {
                // If we're not managing overflow, the containerSize will not account for
                // vertical scrollbar width, so we need to see if there is a vertical
                // scrollbar and subtract its width
                if (canOverflowY && (targetEl.dom.scrollHeight > targetEl.dom.clientHeight)) {
                    // has vertical scrollbar
                    width -= scrollbarSize.width;
                }
            }

            ownerContext.outerCtContext.setProp('width', width + padding.width);
            me.hasOuterCtPxWidth = true;
        }

        if (height && !ownerContext.heightModel.shrinkWrap) {
            if (Ext.supports.PercentageHeightOverflowBug) {
                // set a pixel height on the outerCt if the browser ignores horizontal
                // scrollbar when rendering percentage-height elements
                needsOuterHeight = true;
            }
            if (((Ext.isIE8 && Ext.isStrict) ||
                Ext.isIE7m && Ext.isStrict && isShrinkWrapTpl)) {
                // When using a shrink wrap template and not shrink wrapping, we set a
                // pixel height on the innerCt to support percentage height children in
                // IE6/7/8 strict.
                needsInnerHeight = true;
                // Do not add padding to the innerCt height in IE8 to prevent percentage-
                // height children from adding padding height in their height calculation.
                needsInnerCtPaddingHeight = !Ext.isIE8;
            }

            if ((needsOuterHeight || needsInnerHeight) && canOverflowX && 
                (targetEl.dom.scrollWidth > targetEl.dom.clientWidth)) {
                // adjust the height for scrollbar size since it's not accounted for
                // in the containerSize.
                // IE8 in what passes for "standards" mode does not tolerate -ve sizes
                height = Math.max(height - scrollbarSize.height, 0);
            }

            if (needsOuterHeight) {
                ownerContext.outerCtContext.setProp('height', height + padding.height);
                me.hasOuterCtPxHeight = true;
            }
            
            if (needsInnerHeight) {
                if (needsInnerCtPaddingHeight) {
                    height += padding.height;
                }
                ownerContext.innerCtContext.setProp('height', height);
                me.hasInnerCtPxHeight = true;
            }
        }

        if (Ext.isIE7 && Ext.isStrict && !isShrinkWrapTpl && (overflowYStyle === 'auto')) {
            // IE7 strict has an insane bug where an auto-width element reserves
            // space for its parent's vertical scrollbar if the parent has
            // overflow-y:auto; even when no scrollbar is present.  To workaround
            // this issue we can set overflow-y to 'hidden' and then back to 'auto'.
            // If we have vertical overflow, however, tweaking overflow-y can cause an
            // illegitimate horizontal scrollbar to appear. So we have to tweak overflow-x
            // instead if the overflow-x style is "auto"
            overflowStyleName = (overflowXStyle === 'auto') ? 'overflow-x' : 'overflow-y';
            targetEl.setStyle(overflowStyleName, 'hidden');
            targetEl.setStyle(overflowStyleName, 'auto');
        }
    },

    setupRenderTpl: function (renderTpl) {
        this.callParent(arguments);

        renderTpl.renderPadding = this.doRenderPadding;
    },

    getContentTarget: function(){
        return this.innerCt;
    }

}, function(){
    this.prototype.chromeCellMeasureBug = Ext.isChrome && Ext.chromeVersion >= 26;
});
