/*
Copyright (c) 2009, Yahoo! Inc. All rights reserved.
Code licensed under the BSD License:
http://developer.yahoo.net/yui/license.txt
version: 2.7.0
*/
/**
 * Mechanism to execute a series of callbacks in a non-blocking queue.  Each callback is executed via setTimout unless configured with a negative timeout, in which case it is run in blocking mode in the same execution thread as the previous callback.  Callbacks can be function references or object literals with the following keys:
 * <ul>
 *    <li><code>method</code> - {Function} REQUIRED the callback function.</li>
 *    <li><code>scope</code> - {Object} the scope from which to execute the callback.  Default is the global window scope.</li>
 *    <li><code>argument</code> - {Array} parameters to be passed to method as individual arguments.</li>
 *    <li><code>timeout</code> - {number} millisecond delay to wait after previous callback completion before executing this callback.  Negative values cause immediate blocking execution.  Default 0.</li>
 *    <li><code>until</code> - {Function} boolean function executed before each iteration.  Return true to indicate completion and proceed to the next callback.</li>
 *    <li><code>iterations</code> - {Number} number of times to execute the callback before proceeding to the next callback in the chain. Incompatible with <code>until</code>.</li>
 * </ul>
 *
 * @namespace YAHOO.util
 * @class Chain
 * @constructor
 * @param callback* {Function|Object} Any number of callbacks to initialize the queue
*/
YAHOO.util.Chain = function () {
    /**
     * The callback queue
     * @property q
     * @type {Array}
     * @private
     */
    this.q = [].slice.call(arguments);

    /**
     * Event fired when the callback queue is emptied via execution (not via
     * a call to chain.stop().
     * @event end
     */
    this.createEvent('end');
};

YAHOO.util.Chain.prototype = {
    /**
     * Timeout id used to pause or stop execution and indicate the execution state of the Chain.  0 indicates paused or stopped, -1 indicates blocking execution, and any positive number indicates non-blocking execution.
     * @property id
     * @type {number}
     * @private
     */
    id   : 0,

    /**
     * Begin executing the chain, or resume execution from the last paused position.
     * @method run
     * @return {Chain} the Chain instance
     */
    run : function () {
        // Grab the first callback in the queue
        var c  = this.q[0],
            fn;

        // If there is no callback in the queue or the Chain is currently
        // in an execution mode, return
        if (!c) {
            this.fireEvent('end');
            return this;
        } else if (this.id) {
            return this;
        }

        fn = c.method || c;

        if (typeof fn === 'function') {
            var o    = c.scope || {},
                args = c.argument || [],
                ms   = c.timeout || 0,
                me   = this;
                
            if (!(args instanceof Array)) {
                args = [args];
            }

            // Execute immediately if the callback timeout is negative.
            if (ms < 0) {
                this.id = ms;
                if (c.until) {
                    for (;!c.until();) {
                        // Execute the callback from scope, with argument
                        fn.apply(o,args);
                    }
                } else if (c.iterations) {
                    for (;c.iterations-- > 0;) {
                        fn.apply(o,args);
                    }
                } else {
                    fn.apply(o,args);
                }
                this.q.shift();
                this.id = 0;
                return this.run();
            } else {
                // If the until condition is set, check if we're done
                if (c.until) {
                    if (c.until()) {
                        // Shift this callback from the queue and execute the next
                        // callback
                        this.q.shift();
                        return this.run();
                    }
                // Otherwise if either iterations is not set or we're
                // executing the last iteration, shift callback from the queue
                } else if (!c.iterations || !--c.iterations) {
                    this.q.shift();
                }

                // Otherwise set to execute after the configured timeout
                this.id = setTimeout(function () {
                    // Execute the callback from scope, with argument
                    fn.apply(o,args);
                    // Check if the Chain was not paused from inside the callback
                    if (me.id) {
                        // Indicate ready to run state
                        me.id = 0;
                        // Start the fun all over again
                        me.run();
                    }
                },ms);
            }
        }

        return this;
    },
    
    /**
     * Add a callback to the end of the queue
     * @method add
     * @param c {Function|Object} the callback function ref or object literal
     * @return {Chain} the Chain instance
     */
    add  : function (c) {
        this.q.push(c);
        return this;
    },

    /**
     * Pause the execution of the Chain after the current execution of the
     * current callback completes.  If called interstitially, clears the
     * timeout for the pending callback. Paused Chains can be restarted with
     * chain.run()
     * @method pause
     * @return {Chain} the Chain instance
     */
    pause: function () {
        clearTimeout(this.id);
        this.id = 0;
        return this;
    },

    /**
     * Stop and clear the Chain's queue after the current execution of the
     * current callback completes.
     * @method stop
     * @return {Chain} the Chain instance
     */
    stop : function () { 
        this.pause();
        this.q = [];
        return this;
    }
};
YAHOO.lang.augmentProto(YAHOO.util.Chain,YAHOO.util.EventProvider);

/****************************************************************************/
/****************************************************************************/
/****************************************************************************/

/**
 * The ColumnSet class defines and manages a DataTable's Columns,
 * including nested hierarchies and access to individual Column instances.
 *
 * @namespace YAHOO.widget
 * @class ColumnSet
 * @uses YAHOO.util.EventProvider
 * @constructor
 * @param aDefinitions {Object[]} Array of object literals that define cells in
 * the THEAD.
 */
YAHOO.widget.ColumnSet = function(aDefinitions) {
    this._sId = "yui-cs" + YAHOO.widget.ColumnSet._nCount;

    // First clone the defs
    aDefinitions = YAHOO.widget.DataTable._cloneObject(aDefinitions);
    this._init(aDefinitions);

    YAHOO.widget.ColumnSet._nCount++;
    YAHOO.log("ColumnSet initialized", "info", this.toString());
};

/////////////////////////////////////////////////////////////////////////////
//
// Private member variables
//
/////////////////////////////////////////////////////////////////////////////

/**
 * Internal class variable to index multiple ColumnSet instances.
 *
 * @property ColumnSet._nCount
 * @type Number
 * @private
 * @static
 */
YAHOO.widget.ColumnSet._nCount = 0;

YAHOO.widget.ColumnSet.prototype = {
    /**
     * Unique instance name.
     *
     * @property _sId
     * @type String
     * @private
     */
    _sId : null,

    /**
     * Array of object literal Column definitions passed to the constructor.
     *
     * @property _aDefinitions
     * @type Object[]
     * @private
     */
    _aDefinitions : null,

    /////////////////////////////////////////////////////////////////////////////
    //
    // Public member variables
    //
    /////////////////////////////////////////////////////////////////////////////

    /**
     * Top-down tree representation of Column hierarchy.
     *
     * @property tree
     * @type YAHOO.widget.Column[]
     */
    tree : null,

    /**
     * Flattened representation of all Columns.
     *
     * @property flat
     * @type YAHOO.widget.Column[]
     * @default []
     */
    flat : null,

    /**
     * Array of Columns that map one-to-one to a table column.
     *
     * @property keys
     * @type YAHOO.widget.Column[]
     * @default []
     */
    keys : null,

    /**
     * ID index of nested parent hierarchies for HEADERS accessibility attribute.
     *
     * @property headers
     * @type String[]
     * @default []
     */
    headers : null,

    /////////////////////////////////////////////////////////////////////////////
    //
    // Private methods
    //
    /////////////////////////////////////////////////////////////////////////////

    /**
     * Initializes ColumnSet instance with data from Column definitions.
     *
     * @method _init
     * @param aDefinitions {Object[]} Array of object literals that define cells in
     * the THEAD .
     * @private
     */

    _init : function(aDefinitions) {        
        // DOM tree representation of all Columns
        var tree = [];
        // Flat representation of all Columns
        var flat = [];
        // Flat representation of only Columns that are meant to display data
        var keys = [];
        // Array of HEADERS attribute values for all keys in the "keys" array
        var headers = [];

        // Tracks current node list depth being tracked
        var nodeDepth = -1;

        // Internal recursive function to define Column instances
        var parseColumns = function(nodeList, parent) {
            // One level down
            nodeDepth++;

            // Create corresponding tree node if not already there for this depth
            if(!tree[nodeDepth]) {
                tree[nodeDepth] = [];
            }


            // Parse each node at this depth for attributes and any children
            for(var j=0; j<nodeList.length; j++) {
                var currentNode = nodeList[j];

                // Instantiate a new Column for each node
                var oColumn = new YAHOO.widget.Column(currentNode);
                
                // Cross-reference Column ID back to the original object literal definition
                currentNode.yuiColumnId = oColumn._sId;
                
                // Add the new Column to the flat list
                flat.push(oColumn);

                // Assign its parent as an attribute, if applicable
                if(parent) {
                    oColumn._oParent = parent;
                }

                // The Column has descendants
                if(YAHOO.lang.isArray(currentNode.children)) {
                    oColumn.children = currentNode.children;

                    // Determine COLSPAN value for this Column
                    var terminalChildNodes = 0;
                    var countTerminalChildNodes = function(ancestor) {
                        var descendants = ancestor.children;
                        // Drill down each branch and count terminal nodes
                        for(var k=0; k<descendants.length; k++) {
                            // Keep drilling down
                            if(YAHOO.lang.isArray(descendants[k].children)) {
                                countTerminalChildNodes(descendants[k]);
                            }
                            // Reached branch terminus
                            else {
                                terminalChildNodes++;
                            }
                        }
                    };
                    countTerminalChildNodes(currentNode);
                    oColumn._nColspan = terminalChildNodes;

                    // Cascade certain properties to children if not defined on their own
                    var currentChildren = currentNode.children;
                    for(var k=0; k<currentChildren.length; k++) {
                        var child = currentChildren[k];
                        if(oColumn.className && (child.className === undefined)) {
                            child.className = oColumn.className;
                        }
                        if(oColumn.editor && (child.editor === undefined)) {
                            child.editor = oColumn.editor;
                        }
                        //TODO: Deprecated
                        if(oColumn.editorOptions && (child.editorOptions === undefined)) {
                            child.editorOptions = oColumn.editorOptions;
                        }
                        if(oColumn.formatter && (child.formatter === undefined)) {
                            child.formatter = oColumn.formatter;
                        }
                        if(oColumn.resizeable && (child.resizeable === undefined)) {
                            child.resizeable = oColumn.resizeable;
                        }
                        if(oColumn.sortable && (child.sortable === undefined)) {
                            child.sortable = oColumn.sortable;
                        }
                        if(oColumn.hidden) {
                            child.hidden = true;
                        }
                        if(oColumn.width && (child.width === undefined)) {
                            child.width = oColumn.width;
                        }
                        if(oColumn.minWidth && (child.minWidth === undefined)) {
                            child.minWidth = oColumn.minWidth;
                        }
                        if(oColumn.maxAutoWidth && (child.maxAutoWidth === undefined)) {
                            child.maxAutoWidth = oColumn.maxAutoWidth;
                        }
                        // Backward compatibility
                        if(oColumn.type && (child.type === undefined)) {
                            child.type = oColumn.type;
                        }
                        if(oColumn.type && !oColumn.formatter) {
                            YAHOO.log("The property type has been" +
                            " deprecated in favor of formatter", "warn", oColumn.toString());
                            oColumn.formatter = oColumn.type;
                        }
                        if(oColumn.text && !YAHOO.lang.isValue(oColumn.label)) {
                            YAHOO.log("The property text has been" +
                            " deprecated in favor of label", "warn", oColumn.toString());
                            oColumn.label = oColumn.text;
                        }
                        if(oColumn.parser) {
                            YAHOO.log("The property parser is no longer supported",
                            "warn", this.toString());
                        }
                        if(oColumn.sortOptions && ((oColumn.sortOptions.ascFunction) ||
                                (oColumn.sortOptions.descFunction))) {
                            YAHOO.log("The properties sortOptions.ascFunction and " +
                            " sortOptions.descFunction have been deprecated in favor " +
                            " of sortOptions.sortFunction", "warn", oColumn.toString());
                        }
                    }

                    // The children themselves must also be parsed for Column instances
                    if(!tree[nodeDepth+1]) {
                        tree[nodeDepth+1] = [];
                    }
                    parseColumns(currentChildren, oColumn);
                }
                // This Column does not have any children
                else {
                    oColumn._nKeyIndex = keys.length;
                    oColumn._nColspan = 1;
                    keys.push(oColumn);
                }

                // Add the Column to the top-down tree
                tree[nodeDepth].push(oColumn);
            }
            nodeDepth--;
        };

        // Parse out Column instances from the array of object literals
        if(YAHOO.lang.isArray(aDefinitions)) {
            parseColumns(aDefinitions);

            // Store the array
            this._aDefinitions = aDefinitions;
        }
        else {
            YAHOO.log("Could not initialize ColumnSet due to invalid definitions","error");
            return null;
        }

        var i;

        // Determine ROWSPAN value for each Column in the tree
        var parseTreeForRowspan = function(tree) {
            var maxRowDepth = 1;
            var currentRow;
            var currentColumn;

            // Calculate the max depth of descendants for this row
            var countMaxRowDepth = function(row, tmpRowDepth) {
                tmpRowDepth = tmpRowDepth || 1;

                for(var n=0; n<row.length; n++) {
                    var col = row[n];
                    // Column has children, so keep counting
                    if(YAHOO.lang.isArray(col.children)) {
                        tmpRowDepth++;
                        countMaxRowDepth(col.children, tmpRowDepth);
                        tmpRowDepth--;
                    }
                    // No children, is it the max depth?
                    else {
                        if(tmpRowDepth > maxRowDepth) {
                            maxRowDepth = tmpRowDepth;
                        }
                    }

                }
            };

            // Count max row depth for each row
            for(var m=0; m<tree.length; m++) {
                currentRow = tree[m];
                countMaxRowDepth(currentRow);

                // Assign the right ROWSPAN values to each Column in the row
                for(var p=0; p<currentRow.length; p++) {
                    currentColumn = currentRow[p];
                    if(!YAHOO.lang.isArray(currentColumn.children)) {
                        currentColumn._nRowspan = maxRowDepth;
                    }
                    else {
                        currentColumn._nRowspan = 1;
                    }
                }

                // Reset counter for next row
                maxRowDepth = 1;
            }
        };
        parseTreeForRowspan(tree);

        // Store tree index values
        for(i=0; i<tree[0].length; i++) {
            tree[0][i]._nTreeIndex = i;
        }

        // Store header relationships in an array for HEADERS attribute
        var recurseAncestorsForHeaders = function(i, oColumn) {
            headers[i].push(oColumn.getSanitizedKey());
            if(oColumn._oParent) {
                recurseAncestorsForHeaders(i, oColumn._oParent);
            }
        };
        for(i=0; i<keys.length; i++) {
            headers[i] = [];
            recurseAncestorsForHeaders(i, keys[i]);
            headers[i] = headers[i].reverse();
        }

        // Save to the ColumnSet instance
        this.tree = tree;
        this.flat = flat;
        this.keys = keys;
        this.headers = headers;
    },

    /////////////////////////////////////////////////////////////////////////////
    //
    // Public methods
    //
    /////////////////////////////////////////////////////////////////////////////

    /**
     * Returns unique name of the ColumnSet instance.
     *
     * @method getId
     * @return {String} Unique name of the ColumnSet instance.
     */

    getId : function() {
        return this._sId;
    },

    /**
     * ColumnSet instance name, for logging.
     *
     * @method toString
     * @return {String} Unique name of the ColumnSet instance.
     */

    toString : function() {
        return "ColumnSet instance " + this._sId;
    },

    /**
     * Public accessor to the definitions array.
     *
     * @method getDefinitions
     * @return {Object[]} Array of object literal Column definitions.
     */

    getDefinitions : function() {
        var aDefinitions = this._aDefinitions;
        
        // Internal recursive function to define Column instances
        var parseColumns = function(nodeList, oSelf) {
            // Parse each node at this depth for attributes and any children
            for(var j=0; j<nodeList.length; j++) {
                var currentNode = nodeList[j];
                
                // Get the Column for each node
                var oColumn = oSelf.getColumnById(currentNode.yuiColumnId);
                
                if(oColumn) {    
                    // Update the current values
                    var oDefinition = oColumn.getDefinition();
                    for(var name in oDefinition) {
                        if(YAHOO.lang.hasOwnProperty(oDefinition, name)) {
                            currentNode[name] = oDefinition[name];
                        }
                    }
                }
                            
                // The Column has descendants
                if(YAHOO.lang.isArray(currentNode.children)) {
                    // The children themselves must also be parsed for Column instances
                    parseColumns(currentNode.children, oSelf);
                }
            }
        };

        parseColumns(aDefinitions, this);
        this._aDefinitions = aDefinitions;
        return aDefinitions;
    },

    /**
     * Returns Column instance with given ID.
     *
     * @method getColumnById
     * @param column {String} Column ID.
     * @return {YAHOO.widget.Column} Column instance.
     */

    getColumnById : function(column) {
        if(YAHOO.lang.isString(column)) {
            var allColumns = this.flat;
            for(var i=allColumns.length-1; i>-1; i--) {
                if(allColumns[i]._sId === column) {
                    return allColumns[i];
                }
            }
        }
        return null;
    },

    /**
     * Returns Column instance with given key or ColumnSet key index.
     *
     * @method getColumn
     * @param column {String | Number} Column key or ColumnSet key index.
     * @return {YAHOO.widget.Column} Column instance.
     */

    getColumn : function(column) {
        if(YAHOO.lang.isNumber(column) && this.keys[column]) {
            return this.keys[column];
        }
        else if(YAHOO.lang.isString(column)) {
            var allColumns = this.flat;
            var aColumns = [];
            for(var i=0; i<allColumns.length; i++) {
                if(allColumns[i].key === column) {
                    aColumns.push(allColumns[i]);
                }
            }
            if(aColumns.length === 1) {
                return aColumns[0];
            }
            else if(aColumns.length > 1) {
                return aColumns;
            }
        }
        return null;
    },

    /**
     * Public accessor returns array of given Column's desendants (if any), including itself.
     *
     * @method getDescendants
     * @parem {YAHOO.widget.Column} Column instance.
     * @return {Array} Array including the Column itself and all descendants (if any).
     */
    getDescendants : function(oColumn) {
        var oSelf = this;
        var allDescendants = [];
        var i;

        // Recursive function to loop thru all children
        var parse = function(oParent) {
            allDescendants.push(oParent);
            // This Column has children
            if(oParent.children) {
                for(i=0; i<oParent.children.length; i++) {
                    parse(oSelf.getColumn(oParent.children[i].key));
                }
            }
        };
        parse(oColumn);

        return allDescendants;
    }
};

/****************************************************************************/
/****************************************************************************/
/****************************************************************************/

/**
 * The Column class defines and manages attributes of DataTable Columns
 *
 * @namespace YAHOO.widget
 * @class Column
 * @constructor
 * @param oConfigs {Object} Object literal of definitions.
 */
YAHOO.widget.Column = function(oConfigs) {
    this._sId = "yui-col" + YAHOO.widget.Column._nCount;
    
    // Object literal defines Column attributes
    if(oConfigs && YAHOO.lang.isObject(oConfigs)) {
        for(var sConfig in oConfigs) {
            if(sConfig) {
                this[sConfig] = oConfigs[sConfig];
            }
        }
    }

    // Assign a key if not found
    if(!YAHOO.lang.isValue(this.key)) {
        this.key = "yui-dt-col" + YAHOO.widget.Column._nCount;
    }
    
    // Assign a field if not found, defaults to key
    if(!YAHOO.lang.isValue(this.field)) {
        this.field = this.key;
    }

    // Increment counter
    YAHOO.widget.Column._nCount++;

    // Backward compatibility
    if(this.width && !YAHOO.lang.isNumber(this.width)) {
        this.width = null;
        YAHOO.log("The Column property width must be a number", "warn", this.toString());
    }
    if(this.editor && YAHOO.lang.isString(this.editor)) {
        this.editor = new YAHOO.widget.CellEditor(this.editor, this.editorOptions);
        YAHOO.log("The Column property editor must be an instance of YAHOO.widget.CellEditor", "warn", this.toString());
    }
};

/////////////////////////////////////////////////////////////////////////////
//
// Private member variables
//
/////////////////////////////////////////////////////////////////////////////

YAHOO.lang.augmentObject(YAHOO.widget.Column, {
    /**
     * Internal class variable to index multiple Column instances.
     *
     * @property Column._nCount
     * @type Number
     * @private
     * @static
     */
    _nCount : 0,

    formatCheckbox : function(elCell, oRecord, oColumn, oData) {
        YAHOO.log("The method YAHOO.widget.Column.formatCheckbox() has been" +
        " deprecated in favor of YAHOO.widget.DataTable.formatCheckbox()", "warn",
        "YAHOO.widget.Column.formatCheckbox");
        YAHOO.widget.DataTable.formatCheckbox(elCell, oRecord, oColumn, oData);
    },

    formatCurrency : function(elCell, oRecord, oColumn, oData) {
        YAHOO.log("The method YAHOO.widget.Column.formatCurrency() has been" +
        " deprecated in favor of YAHOO.widget.DataTable.formatCurrency()", "warn",
        "YAHOO.widget.Column.formatCurrency");
        YAHOO.widget.DataTable.formatCurrency(elCell, oRecord, oColumn, oData);
    },

    formatDate : function(elCell, oRecord, oColumn, oData) {
        YAHOO.log("The method YAHOO.widget.Column.formatDate() has been" +
        " deprecated in favor of YAHOO.widget.DataTable.formatDate()", "warn",
        "YAHOO.widget.Column.formatDate");
        YAHOO.widget.DataTable.formatDate(elCell, oRecord, oColumn, oData);
    },

    formatEmail : function(elCell, oRecord, oColumn, oData) {
        YAHOO.log("The method YAHOO.widget.Column.formatEmail() has been" +
        " deprecated in favor of YAHOO.widget.DataTable.formatEmail()", "warn",
        "YAHOO.widget.Column.formatEmail");
        YAHOO.widget.DataTable.formatEmail(elCell, oRecord, oColumn, oData);
    },

    formatLink : function(elCell, oRecord, oColumn, oData) {
        YAHOO.log("The method YAHOO.widget.Column.formatLink() has been" +
        " deprecated in favor of YAHOO.widget.DataTable.formatLink()", "warn",
        "YAHOO.widget.Column.formatLink");
        YAHOO.widget.DataTable.formatLink(elCell, oRecord, oColumn, oData);
    },

    formatNumber : function(elCell, oRecord, oColumn, oData) {
        YAHOO.log("The method YAHOO.widget.Column.formatNumber() has been" +
        " deprecated in favor of YAHOO.widget.DataTable.formatNumber()", "warn",
        "YAHOO.widget.Column.formatNumber");
        YAHOO.widget.DataTable.formatNumber(elCell, oRecord, oColumn, oData);
    },

    formatSelect : function(elCell, oRecord, oColumn, oData) {
        YAHOO.log("The method YAHOO.widget.Column.formatSelect() has been" +
        " deprecated in favor of YAHOO.widget.DataTable.formatDropdown()", "warn",
        "YAHOO.widget.Column.formatSelect");
        YAHOO.widget.DataTable.formatDropdown(elCell, oRecord, oColumn, oData);
    }
});

YAHOO.widget.Column.prototype = {
    /**
     * Unique String identifier assigned at instantiation.
     *
     * @property _sId
     * @type String
     * @private
     */
    _sId : null,

    /**
     * Reference to Column's current position index within its ColumnSet's keys
     * array, if applicable. This property only applies to non-nested and bottom-
     * level child Columns.
     *
     * @property _nKeyIndex
     * @type Number
     * @private
     */
    _nKeyIndex : null,

    /**
     * Reference to Column's current position index within its ColumnSet's tree
     * array, if applicable. This property only applies to non-nested and top-
     * level parent Columns.
     *
     * @property _nTreeIndex
     * @type Number
     * @private
     */
    _nTreeIndex : null,

    /**
     * Number of table cells the Column spans.
     *
     * @property _nColspan
     * @type Number
     * @private
     */
    _nColspan : 1,

    /**
     * Number of table rows the Column spans.
     *
     * @property _nRowspan
     * @type Number
     * @private
     */
    _nRowspan : 1,

    /**
     * Column's parent Column instance, or null.
     *
     * @property _oParent
     * @type YAHOO.widget.Column
     * @private
     */
    _oParent : null,

    /**
     * The DOM reference to the associated TH element.
     *
     * @property _elTh
     * @type HTMLElement
     * @private
     */
    _elTh : null,

    /**
     * The DOM reference to the associated TH element's liner DIV element.
     *
     * @property _elThLiner
     * @type HTMLElement
     * @private
     */
    _elThLiner : null,

    /**
     * The DOM reference to the associated TH element's label SPAN element.
     *
     * @property _elThLabel
     * @type HTMLElement
     * @private
     */
    _elThLabel : null,

    /**
     * The DOM reference to the associated resizerelement (if any).
     *
     * @property _elResizer
     * @type HTMLElement
     * @private
     */
    _elResizer : null,

    /**
     * Internal width tracker.
     *
     * @property _nWidth
     * @type Number
     * @private
     */
    _nWidth : null,

    /**
     * For unreg() purposes, a reference to the Column's DragDrop instance.
     *
     * @property _dd
     * @type YAHOO.util.DragDrop
     * @private
     */
    _dd : null,

    /**
     * For unreg() purposes, a reference to the Column resizer's DragDrop instance.
     *
     * @property _ddResizer
     * @type YAHOO.util.DragDrop
     * @private
     */
    _ddResizer : null,

    /////////////////////////////////////////////////////////////////////////////
    //
    // Public member variables
    //
    /////////////////////////////////////////////////////////////////////////////

    /**
     * Unique name, required.
     *
     * @property key
     * @type String
     */
    key : null,

    /**
     * Associated database field, or null.
     *
     * @property field
     * @type String
     */
    field : null,

    /**
     * Text or HTML for display as Column's label in the TH element.
     *
     * @property label
     * @type String
     */
    label : null,

    /**
     * Column head cell ABBR for accessibility.
     *
     * @property abbr
     * @type String
     */
    abbr : null,

    /**
     * Array of object literals that define children (nested headers) of a Column.
     *
     * @property children
     * @type Object[]
     */
    children : null,

    /**
     * Column width (in pixels).
     *
     * @property width
     * @type Number
     */
    width : null,

    /**
     * Minimum Column width (in pixels).
     *
     * @property minWidth
     * @type Number
     * @default null
     */
    minWidth : null,

    /**
     * When a width is not defined for a Column, maxAutoWidth defines an upper
     * limit that the Column should be auto-sized to. If resizeable is enabled, 
     * users may still resize to a greater width. Most useful for Columns intended
     * to hold long unbroken, unwrapped Strings, such as URLs, to prevent very
     * wide Columns from disrupting visual readability by inducing truncation.
     *
     * @property maxAutoWidth
     * @type Number
     * @default null
     */
    maxAutoWidth : null,

    /**
     * True if Column is in hidden state.
     *
     * @property hidden
     * @type Boolean
     * @default false     
     */
    hidden : false,

    /**
     * True if Column is in selected state.
     *
     * @property selected
     * @type Boolean
     * @default false     
     */
    selected : false,

    /**
     * Custom CSS class or array of classes to be applied to every cell in the Column.
     *
     * @property className
     * @type String || String[]
     */
    className : null,

    /**
     * Defines a format function.
     *
     * @property formatter
     * @type String || HTMLFunction
     */
    formatter : null,
    
    /**
     * Config passed to YAHOO.util.Number.format() by the 'currency' Column formatter.
     *
     * @property currencyOptions
     * @type Object
     * @default null
     */
    currencyOptions : null,

    /**
     * Config passed to YAHOO.util.Date.format() by the 'date' Column formatter.
     *
     * @property dateOptions
     * @type Object
     * @default null
     */
    dateOptions : null,

    /**
     * A CellEditor instance, otherwise Column is not editable.     
     *
     * @property editor
     * @type YAHOO.widget.CellEditor
     */
    editor : null,

    /**
     * True if Column is resizeable, false otherwise. The Drag & Drop Utility is
     * required to enable this feature. Only bottom-level and non-nested Columns are
     * resizeble. 
     *
     * @property resizeable
     * @type Boolean
     * @default false
     */
    resizeable : false,

    /**
     * True if Column is sortable, false otherwise.
     *
     * @property sortable
     * @type Boolean
     * @default false
     */
    sortable : false,

    /**
     * @property sortOptions.defaultOrder
     * @deprecated Use sortOptions.defaultDir.
     */
    /**
     * Default sort direction for Column: YAHOO.widget.DataTable.CLASS_ASC or YAHOO.widget.DataTable.CLASS_DESC.
     *
     * @property sortOptions.defaultDir
     * @type String
     * @default null
     */
    /**
     * Custom field to sort on.
     *
     * @property sortOptions.field
     * @type String
     * @default null
     */
    /**
     * Custom sort handler.
     *
     * @property sortOptions.sortFunction
     * @type Function
     * @default null
     */
    sortOptions : null,















    /////////////////////////////////////////////////////////////////////////////
    //
    // Public methods
    //
    /////////////////////////////////////////////////////////////////////////////

    /**
     * Returns unique ID string.
     *
     * @method getId
     * @return {String} Unique ID string.
     */
    getId : function() {
        return this._sId;
    },

    /**
     * Column instance name, for logging.
     *
     * @method toString
     * @return {String} Column's unique name.
     */
    toString : function() {
        return "Column instance " + this._sId;
    },

    /**
     * Returns object literal definition.
     *
     * @method getDefinition
     * @return {Object} Object literal definition.
     */
    getDefinition : function() {
        var oDefinition = {};
        
        // Update the definition
        oDefinition.abbr = this.abbr;
        oDefinition.className = this.className;
        oDefinition.editor = this.editor;
        oDefinition.editorOptions = this.editorOptions; //TODO: deprecated
        oDefinition.field = this.field;
        oDefinition.formatter = this.formatter;
        oDefinition.hidden = this.hidden;
        oDefinition.key = this.key;
        oDefinition.label = this.label;
        oDefinition.minWidth = this.minWidth;
        oDefinition.maxAutoWidth = this.maxAutoWidth;
        oDefinition.resizeable = this.resizeable;
        oDefinition.selected = this.selected;
        oDefinition.sortable = this.sortable;
        oDefinition.sortOptions = this.sortOptions;
        oDefinition.width = this.width;

        return oDefinition;
    },

    /**
     * Returns unique Column key.
     *
     * @method getKey
     * @return {String} Column key.
     */
    getKey : function() {
        return this.key;
    },
    
    /**
     * Returns field.
     *
     * @method getField
     * @return {String} Column field.
     */
    getField : function() {
        return this.field;
    },
    
    /**
     * Returns Column key which has been sanitized for DOM (class and ID) usage
     * starts with letter, contains only letters, numbers, hyphen, or period.
     *
     * @method getSanitizedKey
     * @return {String} Sanitized Column key.
     */
    getSanitizedKey : function() {
        return this.getKey().replace(/[^\w\-]/g,"");
    },

    /**
     * Public accessor returns Column's current position index within its
     * ColumnSet's keys array, if applicable. Only non-nested and bottom-level
     * child Columns will return a value.
     *
     * @method getKeyIndex
     * @return {Number} Position index, or null.
     */
    getKeyIndex : function() {
        return this._nKeyIndex;
    },

    /**
     * Public accessor returns Column's current position index within its
     * ColumnSet's tree array, if applicable. Only non-nested and top-level parent
     * Columns will return a value;
     *
     * @method getTreeIndex
     * @return {Number} Position index, or null.
     */
    getTreeIndex : function() {
        return this._nTreeIndex;
    },

    /**
     * Public accessor returns Column's parent instance if any, or null otherwise.
     *
     * @method getParent
     * @return {YAHOO.widget.Column} Column's parent instance.
     */
    getParent : function() {
        return this._oParent;
    },

    /**
     * Public accessor returns Column's calculated COLSPAN value.
     *
     * @method getColspan
     * @return {Number} Column's COLSPAN value.
     */
    getColspan : function() {
        return this._nColspan;
    },
    // Backward compatibility
    getColSpan : function() {
        YAHOO.log("The method getColSpan() has been" +
        " deprecated in favor of getColspan()", "warn", this.toString());
        return this.getColspan();
    },

    /**
     * Public accessor returns Column's calculated ROWSPAN value.
     *
     * @method getRowspan
     * @return {Number} Column's ROWSPAN value.
     */
    getRowspan : function() {
        return this._nRowspan;
    },

    /**
     * Returns DOM reference to the key TH element.
     *
     * @method getThEl
     * @return {HTMLElement} TH element.
     */
    getThEl : function() {
        return this._elTh;
    },

    /**
     * Returns DOM reference to the TH's liner DIV element. Introduced since
     * resizeable Columns may have an extra resizer liner, making the DIV liner
     * not reliably the TH element's first child.               
     *
     * @method getThLInerEl
     * @return {HTMLElement} TH element.
     */
    getThLinerEl : function() {
        return this._elThLiner;
    },
    
    /**
     * Returns DOM reference to the resizer element, or null.
     *
     * @method getResizerEl
     * @return {HTMLElement} DIV element.
     */
    getResizerEl : function() {
        return this._elResizer;
    },

    // Backward compatibility
    /**
     * @method getColEl
     * @deprecated Use getThEl
     */
    getColEl : function() {
        YAHOO.log("The method getColEl() has been" +
        " deprecated in favor of getThEl()", "warn",
        this.toString());
        return this.getThEl();
    },
    getIndex : function() {
        YAHOO.log("The method getIndex() has been" +
        " deprecated in favor of getKeyIndex()", "warn",
        this.toString());
        return this.getKeyIndex();
    },
    format : function() {
        YAHOO.log("The method format() has been deprecated in favor of the " +
        "DataTable method formatCell()", "error", this.toString());
    }
};

/****************************************************************************/
/****************************************************************************/
/****************************************************************************/

/**
 * Sort static utility to support Column sorting.
 *
 * @namespace YAHOO.util
 * @class Sort
 * @static
 */
YAHOO.util.Sort = {
    /////////////////////////////////////////////////////////////////////////////
    //
    // Public methods
    //
    /////////////////////////////////////////////////////////////////////////////

    /**
     * Comparator function for simple case-insensitive string sorting.
     *
     * @method compare
     * @param a {Object} First sort argument.
     * @param b {Object} Second sort argument.
     * @param desc {Boolean} True if sort direction is descending, false if
     * sort direction is ascending.
     */
    compare: function(a, b, desc) {
        if((a === null) || (typeof a == "undefined")) {
            if((b === null) || (typeof b == "undefined")) {
                return 0;
            }
            else {
                return 1;
            }
        }
        else if((b === null) || (typeof b == "undefined")) {
            return -1;
        }

        if(a.constructor == String) {
            a = a.toLowerCase();
        }
        if(b.constructor == String) {
            b = b.toLowerCase();
        }
        if(a < b) {
            return (desc) ? 1 : -1;
        }
        else if (a > b) {
            return (desc) ? -1 : 1;
        }
        else {
            return 0;
        }
    }
};

/****************************************************************************/
/****************************************************************************/
/****************************************************************************/

/**
 * ColumnDD subclasses DragDrop to support rearrangeable Columns.
 *
 * @namespace YAHOO.util
 * @class ColumnDD
 * @extends YAHOO.util.DDProxy
 * @constructor
 * @param oDataTable {YAHOO.widget.DataTable} DataTable instance.
 * @param oColumn {YAHOO.widget.Column} Column instance.
 * @param elTh {HTMLElement} TH element reference.
 * @param elTarget {HTMLElement} Drag target element.
 */
YAHOO.widget.ColumnDD = function(oDataTable, oColumn, elTh, elTarget) {
    if(oDataTable && oColumn && elTh && elTarget) {
        this.datatable = oDataTable;
        this.table = oDataTable.getTableEl();
        this.column = oColumn;
        this.headCell = elTh;
        this.pointer = elTarget;
        this.newIndex = null;
        this.init(elTh);
        this.initFrame(); // Needed for DDProxy
        this.invalidHandleTypes = {};

        // Set top/bottom padding to account for children of nested columns
        this.setPadding(10, 0, (this.datatable.getTheadEl().offsetHeight + 10) , 0);

        YAHOO.util.Event.on(window, 'resize', function() {
            this.initConstraints();
        }, this, true);
    }
    else {
        YAHOO.log("Column dragdrop could not be created","warn",oDataTable.toString());
    }
};

if(YAHOO.util.DDProxy) {
    YAHOO.extend(YAHOO.widget.ColumnDD, YAHOO.util.DDProxy, {
        initConstraints: function() {
            //Get the top, right, bottom and left positions
            var region = YAHOO.util.Dom.getRegion(this.table),
                //Get the element we are working on
                el = this.getEl(),
                //Get the xy position of it
                xy = YAHOO.util.Dom.getXY(el),
                //Get the width and height
                width = parseInt(YAHOO.util.Dom.getStyle(el, 'width'), 10),
                height = parseInt(YAHOO.util.Dom.getStyle(el, 'height'), 10),
                //Set left to x minus left
                left = ((xy[0] - region.left) + 15), //Buffer of 15px
                //Set right to right minus x minus width
                right = ((region.right - xy[0] - width) + 15);
    
            //Set the constraints based on the above calculations
            this.setXConstraint(left, right);
            this.setYConstraint(10, 10);            
        },
        _resizeProxy: function() {
            this.constructor.superclass._resizeProxy.apply(this, arguments);
            var dragEl = this.getDragEl(),
                el = this.getEl();

            YAHOO.util.Dom.setStyle(this.pointer, 'height', (this.table.parentNode.offsetHeight + 10) + 'px');
            YAHOO.util.Dom.setStyle(this.pointer, 'display', 'block');
            var xy = YAHOO.util.Dom.getXY(el);
            YAHOO.util.Dom.setXY(this.pointer, [xy[0], (xy[1] - 5)]);
            
            YAHOO.util.Dom.setStyle(dragEl, 'height', this.datatable.getContainerEl().offsetHeight + "px");
            YAHOO.util.Dom.setStyle(dragEl, 'width', (parseInt(YAHOO.util.Dom.getStyle(dragEl, 'width'),10) + 4) + 'px');
            YAHOO.util.Dom.setXY(this.dragEl, xy);
        },
        onMouseDown: function() {
                this.initConstraints();
                this.resetConstraints();
        },
        clickValidator: function(e) {
            if(!this.column.hidden) {
                var target = YAHOO.util.Event.getTarget(e);
                return ( this.isValidHandleChild(target) &&
                            (this.id == this.handleElId ||
                                this.DDM.handleWasClicked(target, this.id)) );
            }
        },
        onDragOver: function(ev, id) {
            // Validate target as a Column
            var target = this.datatable.getColumn(id);
            if(target) {                
                // Validate target as a top-level parent
                var targetIndex = target.getTreeIndex();
                while((targetIndex === null) && target.getParent()) {
                    target = target.getParent();
                    targetIndex = target.getTreeIndex();
                }
                if(targetIndex !== null) {
                    // Are we placing to left or right of target?
                    var elTarget = target.getThEl();
                    var newIndex = targetIndex;
                    var mouseX = YAHOO.util.Event.getPageX(ev),
                        targetX = YAHOO.util.Dom.getX(elTarget),
                        midX = targetX + ((YAHOO.util.Dom.get(elTarget).offsetWidth)/2),
                        currentIndex =  this.column.getTreeIndex();
                    
                    if (mouseX < midX) {
                       YAHOO.util.Dom.setX(this.pointer, targetX);
                    } else {
                        var targetWidth = parseInt(elTarget.offsetWidth, 10);
                        YAHOO.util.Dom.setX(this.pointer, (targetX + targetWidth));
                        newIndex++;
                    }
                    if (targetIndex > currentIndex) {
                        newIndex--;
                    }
                    if(newIndex < 0) {
                        newIndex = 0;
                    }
                    else if(newIndex > this.datatable.getColumnSet().tree[0].length) {
                        newIndex = this.datatable.getColumnSet().tree[0].length;
                    }
                    this.newIndex = newIndex;
                }
            }
        },
        onDragDrop: function() {
            this.datatable.reorderColumn(this.column, this.newIndex);
        },
        endDrag: function() {
            this.newIndex = null;
            YAHOO.util.Dom.setStyle(this.pointer, 'display', 'none');
        }
    });
}

/****************************************************************************/
/****************************************************************************/
/****************************************************************************/

/**
 * ColumnResizer subclasses DragDrop to support resizeable Columns.
 *
 * @namespace YAHOO.util
 * @class ColumnResizer
 * @extends YAHOO.util.DDProxy
 * @constructor
 * @param oDataTable {YAHOO.widget.DataTable} DataTable instance.
 * @param oColumn {YAHOO.widget.Column} Column instance.
 * @param elTh {HTMLElement} TH element reference.
 * @param sHandleElId {String} DOM ID of the handle element that causes the resize.
 * @param elProxy {HTMLElement} Resizer proxy element.
 */
YAHOO.util.ColumnResizer = function(oDataTable, oColumn, elTh, sHandleId, elProxy) {
    if(oDataTable && oColumn && elTh && sHandleId) {
        this.datatable = oDataTable;
        this.column = oColumn;
        this.headCell = elTh;
        this.headCellLiner = oColumn.getThLinerEl();
        this.resizerLiner = elTh.firstChild;
        this.init(sHandleId, sHandleId, {dragOnly:true, dragElId: elProxy.id});
        this.initFrame(); // Needed for proxy
        this.resetResizerEl(); // Needed when rowspan > 0

        // Set right padding for bug 1858462
        this.setPadding(0, 1, 0, 0);
    }
    else {
        YAHOO.log("Column resizer could not be created","warn",oDataTable.toString());
    }
};

if(YAHOO.util.DD) {
    YAHOO.extend(YAHOO.util.ColumnResizer, YAHOO.util.DDProxy, {
        /////////////////////////////////////////////////////////////////////////////
        //
        // Public methods
        //
        /////////////////////////////////////////////////////////////////////////////
        /**
         * Resets resizer element.
         *
         * @method resetResizerEl
         */
        resetResizerEl : function() {
            var resizerStyle = YAHOO.util.Dom.get(this.handleElId).style;
            resizerStyle.left = "auto";
            resizerStyle.right = 0;
            resizerStyle.top = "auto";
            resizerStyle.bottom = 0;
            resizerStyle.height = this.headCell.offsetHeight+"px";
        },
    
        /////////////////////////////////////////////////////////////////////////////
        //
        // Public DOM event handlers…