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/*
 * File:        ColReorder.js
 * Version:     1.0.2
 * CVS:         $Id$
 * Description: Controls for column visiblity in DataTables
 * Author:      Allan Jardine (www.sprymedia.co.uk)
 * Created:     Wed Sep 15 18:23:29 BST 2010
 * Modified:    $Date$ by $Author$
 * Language:    Javascript
 * License:     GPL v2 or BSD 3 point style
 * Project:     DataTables
 * Contact:     www.sprymedia.co.uk/contact
 * 
 * Copyright 2010-2011 Allan Jardine, all rights reserved.
 *
 * This source file is free software, under either the GPL v2 license or a
 * BSD style license, available at:
 *   http://datatables.net/license_gpl2
 *   http://datatables.net/license_bsd
 *
 */


(function($, window, document) {


/**
 * Switch the key value pairing of an index array to be value key (i.e. the old value is now the
 * key). For example consider [ 2, 0, 1 ] this would be returned as [ 1, 2, 0 ].
 *  @method  fnInvertKeyValues
 *  @param   array aIn Array to switch around
 *  @returns array
 */
function fnInvertKeyValues( aIn )
{
        var aRet=[];
        for ( var i=0, iLen=aIn.length ; i<iLen ; i++ )
        {
                aRet[ aIn[i] ] = i;
        }
        return aRet;
}


/**
 * Modify an array by switching the position of two elements
 *  @method  fnArraySwitch
 *  @param   array aArray Array to consider, will be modified by reference (i.e. no return)
 *  @param   int iFrom From point
 *  @param   int iTo Insert point
 *  @returns void
 */
function fnArraySwitch( aArray, iFrom, iTo )
{
        var mStore = aArray.splice( iFrom, 1 )[0];
        aArray.splice( iTo, 0, mStore );
}


/**
 * Switch the positions of nodes in a parent node (note this is specifically designed for 
 * table rows). Note this function considers all element nodes under the parent!
 *  @method  fnDomSwitch
 *  @param   string sTag Tag to consider
 *  @param   int iFrom Element to move
 *  @param   int Point to element the element to (before this point), can be null for append
 *  @returns void
 */
function fnDomSwitch( nParent, iFrom, iTo )
{
        var anTags = [];
        for ( var i=0, iLen=nParent.childNodes.length ; i<iLen ; i++ )
        {
                if ( nParent.childNodes[i].nodeType == 1 )
                {
                        anTags.push( nParent.childNodes[i] );
                }
        }
        var nStore = anTags[ iFrom ];
        
        if ( iTo !== null )
        {
                nParent.insertBefore( nStore, anTags[iTo] );
        }
        else
        {
                nParent.appendChild( nStore );
        }
}



/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * DataTables plug-in API functions
 *
 * This are required by ColReorder in order to perform the tasks required, and also keep this
 * code portable, to be used for other column reordering projects with DataTables, if needed.
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */


/**
 * Plug-in for DataTables which will reorder the internal column structure by taking the column
 * from one position (iFrom) and insert it into a given point (iTo).
 *  @method  $.fn.dataTableExt.oApi.fnColReorder
 *  @param   object oSettings DataTables settings object - automatically added by DataTables! 
 *  @param   int iFrom Take the column to be repositioned from this point
 *  @param   int iTo and insert it into this point
 *  @returns void
 */
$.fn.dataTableExt.oApi.fnColReorder = function ( oSettings, iFrom, iTo )
{
        var i, iLen, j, jLen, iCols=oSettings.aoColumns.length, nTrs;
        
        /* Sanity check in the input */
        if ( iFrom == iTo )
        {
                /* Pointless reorder */
                return;
        }
        
        if ( iFrom < 0 || iFrom >= iCols )
        {
                this.oApi._fnLog( oSettings, 1, "ColReorder 'from' index is out of bounds: "+iFrom );
                return;
        }
        
        if ( iTo < 0 || iTo >= iCols )
        {
                this.oApi._fnLog( oSettings, 1, "ColReorder 'to' index is out of bounds: "+iTo );
                return;
        }
        
        /*
         * Calculate the new column array index, so we have a mapping between the old and new
         */
        var aiMapping = [];
        for ( i=0, iLen=iCols ; i<iLen ; i++ )
        {
                aiMapping[i] = i;
        }
        fnArraySwitch( aiMapping, iFrom, iTo );
        var aiInvertMapping = fnInvertKeyValues( aiMapping );
        
        
        /*
         * Convert all internal indexing to the new column order indexes
         */
        /* Sorting */
        for ( i=0, iLen=oSettings.aaSorting.length ; i<iLen ; i++ )
        {
                oSettings.aaSorting[i][0] = aiInvertMapping[ oSettings.aaSorting[i][0] ];
        }
        
        /* Fixed sorting */
        if ( oSettings.aaSortingFixed !== null )
        {
                for ( i=0, iLen=oSettings.aaSortingFixed.length ; i<iLen ; i++ )
                {
                        oSettings.aaSortingFixed[i][0] = aiInvertMapping[ oSettings.aaSortingFixed[i][0] ];
                }
        }
        
        /* Data column sorting (the column which the sort for a given column should take place on) */
        for ( i=0, iLen=iCols ; i<iLen ; i++ )
        {
                oSettings.aoColumns[i].iDataSort = aiInvertMapping[ oSettings.aoColumns[i].iDataSort ];
        }
        
        
        /*
         * Move the DOM elements
         */
        if ( oSettings.aoColumns[iFrom].bVisible )
        {
                /* Calculate the current visible index and the point to insert the node before. The insert
                 * before needs to take into account that there might not be an element to insert before,
                 * in which case it will be null, and an appendChild should be used
                 */
                var iVisibleIndex = this.oApi._fnColumnIndexToVisible( oSettings, iFrom );
                var iInsertBeforeIndex = null;
                
                i = iTo < iFrom ? iTo : iTo + 1;
                while ( iInsertBeforeIndex === null && i < iCols )
                {
                        iInsertBeforeIndex = this.oApi._fnColumnIndexToVisible( oSettings, i );
                        i++;
                }
                
                /* Header */
                nTrs = oSettings.nTHead.getElementsByTagName('tr');
                for ( i=0, iLen=nTrs.length ; i<iLen ; i++ )
                {
                        fnDomSwitch( nTrs[i], iVisibleIndex, iInsertBeforeIndex );
                }
                
                /* Footer */
                if ( oSettings.nTFoot !== null )
                {
                        nTrs = oSettings.nTFoot.getElementsByTagName('tr');
                        for ( i=0, iLen=nTrs.length ; i<iLen ; i++ )
                        {
                                fnDomSwitch( nTrs[i], iVisibleIndex, iInsertBeforeIndex );
                        }
                }
                
                /* Body */
                for ( i=0, iLen=oSettings.aoData.length ; i<iLen ; i++ )
                {
                        fnDomSwitch( oSettings.aoData[i].nTr, iVisibleIndex, iInsertBeforeIndex );
                }
        }
        
        
        /* 
         * Move the internal array elements
         */
        /* Columns */
        fnArraySwitch( oSettings.aoColumns, iFrom, iTo );
        
        /* Search columns */
        fnArraySwitch( oSettings.aoPreSearchCols, iFrom, iTo );
        
        /* Array array - internal data anodes cache */
        for ( i=0, iLen=oSettings.aoData.length ; i<iLen ; i++ )
        {
                if ( $.isArray( oSettings.aoData[i]._aData ) ) {
                  fnArraySwitch( oSettings.aoData[i]._aData, iFrom, iTo );
                }
                fnArraySwitch( oSettings.aoData[i]._anHidden, iFrom, iTo );
        }
        
        /* Reposition the header elements in the header layout array */
        for ( i=0, iLen=oSettings.aoHeader.length ; i<iLen ; i++ )
        {
                fnArraySwitch( oSettings.aoHeader[i], iFrom, iTo );
        }
        
        if ( oSettings.aoFooter !== null )
        {
                for ( i=0, iLen=oSettings.aoFooter.length ; i<iLen ; i++ )
                {
                        fnArraySwitch( oSettings.aoFooter[i], iFrom, iTo );
                }
        }
        
        
        /*
         * Update DataTables' event handlers
         */
        
        /* Sort listener */
        for ( i=0, iLen=iCols ; i<iLen ; i++ )
        {
                $(oSettings.aoColumns[i].nTh).unbind('click');
                this.oApi._fnSortAttachListener( oSettings, oSettings.aoColumns[i].nTh, i );
        }
        
        
        /*
         * Any extra operations for the other plug-ins
         */
        if ( typeof ColVis != 'undefined' )
        {
                ColVis.fnRebuild( oSettings.oInstance );
        }
        
        if ( typeof oSettings.oInstance._oPluginFixedHeader != 'undefined' )
        {
                oSettings.oInstance._oPluginFixedHeader.fnUpdate();
        }
};




/** 
 * ColReorder provides column visiblity control for DataTables
 * @class ColReorder
 * @constructor
 * @param {object} DataTables object
 * @param {object} ColReorder options
 */
ColReorder = function( oTable, oOpts )
{
        /* Santiy check that we are a new instance */
        if ( !this.CLASS || this.CLASS != "ColReorder" )
        {
                alert( "Warning: ColReorder must be initialised with the keyword 'new'" );
        }
        
        if ( typeof oOpts == 'undefined' )
        {
                oOpts = {};
        }
        
        
        /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
         * Public class variables
         * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
        
        /**
         * @namespace Settings object which contains customisable information for ColReorder instance
         */
        this.s = {
                /**
                 * DataTables settings object
                 *  @property dt
                 *  @type     Object
                 *  @default  null
                 */
                "dt": null,
                
                /**
                 * Initialisation object used for this instance
                 *  @property init
                 *  @type     object
                 *  @default  {}
                 */
                "init": oOpts,
                
                /**
                 * Number of columns to fix (not allow to be reordered)
                 *  @property fixed
                 *  @type     int
                 *  @default  0
                 */
                "fixed": 0,
                
                /**
                 * @namespace Information used for the mouse drag
                 */
                "mouse": {
                        "startX": -1,
                        "startY": -1,
                        "offsetX": -1,
                        "offsetY": -1,
                        "target": -1,
                        "targetIndex": -1,
                        "fromIndex": -1
                },
                
                /**
                 * Information which is used for positioning the insert cusor and knowing where to do the
                 * insert. Array of objects with the properties:
                 *   x: x-axis position
                 *   to: insert point
                 *  @property aoTargets
                 *  @type     array
                 *  @default  []
                 */
                "aoTargets": []
        };
        
        
        /**
         * @namespace Common and useful DOM elements for the class instance
         */
        this.dom = {
                /**
                 * Dragging element (the one the mouse is moving)
                 *  @property drag
                 *  @type     element
                 *  @default  null
                 */
                "drag": null,
                
                /**
                 * The insert cursor
                 *  @property pointer
                 *  @type     element
                 *  @default  null
                 */
                "pointer": null
        };
        
        
        /* Constructor logic */
        this.s.dt = oTable.fnSettings();
        this._fnConstruct();
        
        /* Store the instance for later use */
        ColReorder.aoInstances.push( this );
        return this;
};



ColReorder.prototype = {
        /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
         * Public methods
         * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
        
        "fnReset": function ()
        {
                var a = [];
                for ( var i=0, iLen=this.s.dt.aoColumns.length ; i<iLen ; i++ )
                {
                        a.push( this.s.dt.aoColumns[i]._ColReorder_iOrigCol );
                }
                
                this._fnOrderColumns( a );
        },
        
        
        /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
         * Private methods (they are of course public in JS, but recommended as private)
         * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
        
        /**
         * Constructor logic
         *  @method  _fnConstruct
         *  @returns void
         *  @private 
         */
        "_fnConstruct": function ()
        {
                var that = this;
                var i, iLen;
                
                /* Columns discounted from reordering - counting left to right */
                if ( typeof this.s.init.iFixedColumns != 'undefined' )
                {
                        this.s.fixed = this.s.init.iFixedColumns;
                }
                
                /* Add event handlers for the drag and drop, and also mark the original column order */
                for ( i=0, iLen=this.s.dt.aoColumns.length ; i<iLen ; i++ )
                {
                        if ( i > this.s.fixed-1 )
                        {
                                this._fnMouseListener( i, this.s.dt.aoColumns[i].nTh );
                        }
                        
                        /* Mark the original column order for later reference */
                        this.s.dt.aoColumns[i]._ColReorder_iOrigCol = i;
                }
                
                /* State saving */
                this.s.dt.aoStateSave.push( {
                        "fn": function (oS, sVal) {
                                return that._fnStateSave.call( that, sVal );
                        },
                        "sName": "ColReorder_State"
                } );
                
                /* An initial column order has been specified */
                var aiOrder = null;
                if ( typeof this.s.init.aiOrder != 'undefined' )
                {
                        aiOrder = this.s.init.aiOrder.slice();
                }
                
                /* State loading, overrides the column order given */
                if ( this.s.dt.oLoadedState && typeof this.s.dt.oLoadedState.ColReorder != 'undefined' &&
                  this.s.dt.oLoadedState.ColReorder.length == this.s.dt.aoColumns.length )
                {
                        aiOrder = this.s.dt.oLoadedState.ColReorder;
                }
                
                /* If we have an order to apply - do so */
                if ( aiOrder )
                {
                        /* We might be called during or after the DataTables initialisation. If before, then we need
                         * to wait until the draw is done, if after, then do what we need to do right away
                         */
                        if ( !that.s.dt._bInitComplete )
                        {
                                var bDone = false;
                                this.s.dt.aoDrawCallback.push( {
                                        "fn": function () {
                                                if ( !that.s.dt._bInitComplete && !bDone )
                                                {
                                                        bDone = true;
                                                        var resort = fnInvertKeyValues( aiOrder );
                                                        that._fnOrderColumns.call( that, resort );
                                                }
                                        },
                                        "sName": "ColReorder_Pre"
                                } );
                        }
                        else
                        {
                                var resort = fnInvertKeyValues( aiOrder );
                                that._fnOrderColumns.call( that, resort );
                        }
                }
        },
        
        
        /**
         * Set the column order from an array
         *  @method  _fnOrderColumns
         *  @param   array a An array of integers which dictate the column order that should be applied
         *  @returns void
         *  @private 
         */
        "_fnOrderColumns": function ( a )
        {
                if ( a.length != this.s.dt.aoColumns.length )
                {
                        this.s.dt.oInstance.oApi._fnLog( oDTSettings, 1, "ColReorder - array reorder does not "+
                                "match known number of columns. Skipping." );
                        return;
                }
                
                for ( var i=0, iLen=a.length ; i<iLen ; i++ )
                {
                        var currIndex = $.inArray( i, a );
                        if ( i != currIndex )
                        {
                                /* Reorder our switching array */
                                fnArraySwitch( a, currIndex, i );
                                
                                /* Do the column reorder in the table */
                                this.s.dt.oInstance.fnColReorder( currIndex, i );
                        }
                }
                
                /* When scrolling we need to recalculate the column sizes to allow for the shift */
                if ( this.s.dt.oScroll.sX !== "" || this.s.dt.oScroll.sY !== "" )
                {
                        this.s.dt.oInstance.fnAdjustColumnSizing();
                }
                        
                /* Save the state */
                this.s.dt.oInstance.oApi._fnSaveState( this.s.dt );
        },
        
        
        /**
         * This function effectively replaces the state saving function in DataTables (this is needed
         * because otherwise DataTables would state save the columns in their reordered state, not the
         * original which is needed on first draw). This is sensitive to any changes in the DataTables
         * state saving method!
         *  @method  _fnStateSave
         *  @param   string sCurrentVal 
         *  @returns string JSON encoded cookie string for DataTables
         *  @private 
         */
        "_fnStateSave": function ( sCurrentVal )
        {
                var i, iLen, sTmp;
                var sValue = sCurrentVal.split('"aaSorting"')[0];
                var a = [];
                var oSettings = this.s.dt;
                
                /* Sorting */
                sValue += '"aaSorting":[ ';
                for ( i=0 ; i<oSettings.aaSorting.length ; i++ )
                {
                        sValue += '['+oSettings.aoColumns[ oSettings.aaSorting[i][0] ]._ColReorder_iOrigCol+
                                ',"'+oSettings.aaSorting[i][1]+'"],';
                }
                sValue = sValue.substring(0, sValue.length-1);
                sValue += "],";
                
                /* Column filter */
                for ( i=0, iLen=oSettings.aoColumns.length ; i<iLen ; i++ )
                {
                        a[ oSettings.aoColumns[i]._ColReorder_iOrigCol ] = {
                                "sSearch": encodeURIComponent(oSettings.aoPreSearchCols[i].sSearch),
                                "bRegex": !oSettings.aoPreSearchCols[i].bRegex
                        };
                }
                
                sValue += '"aaSearchCols":[ ';
                for ( i=0 ; i<a.length ; i++ )
                {
                        sValue += '["'+a[i].sSearch+'",'+a[i].bRegex+'],';
                }
                sValue = sValue.substring(0, sValue.length-1);
                sValue += "],";
                
                /* Visibility */
                a = [];
                for ( i=0, iLen=oSettings.aoColumns.length ; i<iLen ; i++ )
                {
                        a[ oSettings.aoColumns[i]._ColReorder_iOrigCol ] = oSettings.aoColumns[i].bVisible;
                }
                
                sValue += '"abVisCols":[ ';
                for ( i=0 ; i<a.length ; i++ )
                {
                        sValue += a[i]+",";
                }
                sValue = sValue.substring(0, sValue.length-1);
                sValue += "],";
                
                /* Column reordering */
                a = [];
                for ( i=0, iLen=oSettings.aoColumns.length ; i<iLen ; i++ ) {
                        a.push( oSettings.aoColumns[i]._ColReorder_iOrigCol );
                }
                sValue += '"ColReorder":['+a.join(',')+']';
                
                return sValue;
        },
        
        
        /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
         * Mouse drop and drag
         */
        
        /**
         * Add a mouse down listener to a particluar TH element
         *  @method  _fnMouseListener
         *  @param   int i Column index
         *  @param   element nTh TH element clicked on
         *  @returns void
         *  @private 
         */
        "_fnMouseListener": function ( i, nTh )
        {
                var that = this;
                $(nTh).bind( 'mousedown.ColReorder', function (e) {
                        that._fnMouseDown.call( that, e, nTh );
                        return false;
                } );
        },
        
        
        /**
         * Mouse down on a TH element in the table header
         *  @method  _fnMouseDown
         *  @param   event e Mouse event
         *  @param   element nTh TH element to be dragged
         *  @returns void
         *  @private 
         */
        "_fnMouseDown": function ( e, nTh )
        {
                var
                        that = this,
                        aoColumns = this.s.dt.aoColumns;
                
                /* Store information about the mouse position */
                var nThTarget = e.target.nodeName == "TH" ? e.target : $(e.target).parents('TH')[0];
                var offset = $(nThTarget).offset();
                this.s.mouse.startX = e.pageX;
                this.s.mouse.startY = e.pageY;
                this.s.mouse.offsetX = e.pageX - offset.left;
                this.s.mouse.offsetY = e.pageY - offset.top;
                this.s.mouse.target = nTh;
                this.s.mouse.targetIndex = $('th', nTh.parentNode).index( nTh );
                this.s.mouse.fromIndex = this.s.dt.oInstance.oApi._fnVisibleToColumnIndex( this.s.dt, 
                        this.s.mouse.targetIndex );
                
                /* Calculate a cached array with the points of the column inserts, and the 'to' points */
                this.s.aoTargets.splice( 0, this.s.aoTargets.length );
                
                this.s.aoTargets.push( {
                        "x":  $(this.s.dt.nTable).offset().left,
                        "to": 0
                } );
                
                var iToPoint = 0;
                for ( var i=0, iLen=aoColumns.length ; i<iLen ; i++ )
                {
                        /* For the column / header in question, we want it's position to remain the same if the 
                         * position is just to it's immediate left or right, so we only incremement the counter for
                         * other columns
                         */
                        if ( i != this.s.mouse.fromIndex )
                        {
                                iToPoint++;
                        }
                        
                        if ( aoColumns[i].bVisible )
                        {
                                this.s.aoTargets.push( {
                                        "x":  $(aoColumns[i].nTh).offset().left + $(aoColumns[i].nTh).outerWidth(),
                                        "to": iToPoint
                                } );
                        }
                }
                
                /* Disallow columns for being reordered by drag and drop, counting left to right */
                if ( this.s.fixed !== 0 )
                {
                        this.s.aoTargets.splice( 0, this.s.fixed );
                }
                
                /* Add event handlers to the document */
                $(document).bind( 'mousemove.ColReorder', function (e) {
                        that._fnMouseMove.call( that, e );
                } );
                
                $(document).bind( 'mouseup.ColReorder', function (e) {
                        that._fnMouseUp.call( that, e );
                } );
        },
        
        
        /**
         * Deal with a mouse move event while dragging a node
         *  @method  _fnMouseMove
         *  @param   event e Mouse event
         *  @returns void
         *  @private 
         */
        "_fnMouseMove": function ( e )
        {
                var that = this;
                
                if ( this.dom.drag === null )
                {
                        /* Only create the drag element if the mouse has moved a specific distance from the start
                         * point - this allows the user to make small mouse movements when sorting and not have a
                         * possibly confusing drag element showing up
                         */
                        if ( Math.pow(
                                Math.pow(e.pageX - this.s.mouse.startX, 2) + 
                                Math.pow(e.pageY - this.s.mouse.startY, 2), 0.5 ) < 5 )
                        {
                                return;
                        }
                        this._fnCreateDragNode();
                }
                
                /* Position the element - we respect where in the element the click occured */
                this.dom.drag.style.left = (e.pageX - this.s.mouse.offsetX) + "px";
                this.dom.drag.style.top = (e.pageY - this.s.mouse.offsetY) + "px";
                
                /* Based on the current mouse position, calculate where the insert should go */
                var bSet = false;
                for ( var i=1, iLen=this.s.aoTargets.length ; i<iLen ; i++ )
                {
                        if ( e.pageX < this.s.aoTargets[i-1].x + ((this.s.aoTargets[i].x-this.s.aoTargets[i-1].x)/2) )
                        {
                                this.dom.pointer.style.left = this.s.aoTargets[i-1].x +"px";
                                this.s.mouse.toIndex = this.s.aoTargets[i-1].to;
                                bSet = true;
                                break;
                        }
                }
                
                /* The insert element wasn't positioned in the array (less than operator), so we put it at 
                 * the end
                 */
                if ( !bSet )
                {
                        this.dom.pointer.style.left = this.s.aoTargets[this.s.aoTargets.length-1].x +"px";
                        this.s.mouse.toIndex = this.s.aoTargets[this.s.aoTargets.length-1].to;
                }
        },
        
        
        /**
         * Finish off the mouse drag and insert the column where needed
         *  @method  _fnMouseUp
         *  @param   event e Mouse event
         *  @returns void
         *  @private 
         */
        "_fnMouseUp": function ( e )
        {
                var that = this;
                
                $(document).unbind( 'mousemove.ColReorder' );
                $(document).unbind( 'mouseup.ColReorder' );
                
                if ( this.dom.drag !== null )
                {
                        /* Remove the guide elements */
                        document.body.removeChild( this.dom.drag );
                        document.body.removeChild( this.dom.pointer );
                        this.dom.drag = null;
                        this.dom.pointer = null;
                        
                        /* Actually do the reorder */
                        this.s.dt.oInstance.fnColReorder( this.s.mouse.fromIndex, this.s.mouse.toIndex );
                        
                        /* When scrolling we need to recalculate the column sizes to allow for the shift */
                        if ( this.s.dt.oScroll.sX !== "" || this.s.dt.oScroll.sY !== "" )
                        {
                                this.s.dt.oInstance.fnAdjustColumnSizing();
                        }
                        
                        /* Save the state */
                        this.s.dt.oInstance.oApi._fnSaveState( this.s.dt );
                }
        },
        
        
        /**
         * Copy the TH element that is being drags so the user has the idea that they are actually 
         * moving it around the page.
         *  @method  _fnCreateDragNode
         *  @returns void
         *  @private 
         */
        "_fnCreateDragNode": function ()
        {
                var that = this;
                
                this.dom.drag = $(this.s.dt.nTHead.parentNode).clone(true)[0];
                this.dom.drag.className += " DTCR_clonedTable";
                while ( this.dom.drag.getElementsByTagName('tbody').length > 0 )
                {
                        this.dom.drag.removeChild( this.dom.drag.getElementsByTagName('tbody')[0] );
                }
                while ( this.dom.drag.getElementsByTagName('tfoot').length > 0 )
                {
                        this.dom.drag.removeChild( this.dom.drag.getElementsByTagName('tfoot')[0] );
                }
                
                $('thead tr:eq(0)', this.dom.drag).each( function () {
                        $('th:not(:eq('+that.s.mouse.targetIndex+'))', this).remove();
                } );
                $('tr', this.dom.drag).height( $('tr:eq(0)', that.s.dt.nTHead).height() );
                
                $('thead tr:gt(0)', this.dom.drag).remove();
                
                $('thead th:eq(0)', this.dom.drag).each( function (i) {
                        this.style.width = $('th:eq('+that.s.mouse.targetIndex+')', that.s.dt.nTHead).width()+"px";
                } );
                
                this.dom.drag.style.position = "absolute";
                this.dom.drag.style.top = "0px";
                this.dom.drag.style.left = "0px";
                this.dom.drag.style.width = $('th:eq('+that.s.mouse.targetIndex+')', that.s.dt.nTHead).outerWidth()+"px";
                
                
                this.dom.pointer = document.createElement( 'div' );
                this.dom.pointer.className = "DTCR_pointer";
                this.dom.pointer.style.position = "absolute";
                
                if ( this.s.dt.oScroll.sX === "" && this.s.dt.oScroll.sY === "" )
                {
                        this.dom.pointer.style.top = $(this.s.dt.nTable).offset().top+"px";
                        this.dom.pointer.style.height = $(this.s.dt.nTable).height()+"px";
                }
                else
                {
                        this.dom.pointer.style.top = $('div.dataTables_scroll', this.s.dt.nTableWrapper).offset().top+"px";
                        this.dom.pointer.style.height = $('div.dataTables_scroll', this.s.dt.nTableWrapper).height()+"px";
                }
        
                document.body.appendChild( this.dom.pointer );
                document.body.appendChild( this.dom.drag );
        }
};





/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Static parameters
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/**
 * Array of all ColReorder instances for later reference
 *  @property ColReorder.aoInstances
 *  @type     array
 *  @default  []
 *  @static
 */
ColReorder.aoInstances = [];





/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Static functions
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/**
 * Reset the column ordering for a DataTables instance
 *  @method  ColReorder.fnReset
 *  @param   object oTable DataTables instance to consider
 *  @returns void
 *  @static
 */
ColReorder.fnReset = function ( oTable )
{
        for ( var i=0, iLen=ColReorder.aoInstances.length ; i<iLen ; i++ )
        {
                if ( ColReorder.aoInstances[i].s.dt.oInstance == oTable )
                {
                        ColReorder.aoInstances[i].fnReset();
                }
        }
};





/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Constants
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/**
 * Name of this class
 *  @constant CLASS
 *  @type     String
 *  @default  ColReorder
 */
ColReorder.prototype.CLASS = "ColReorder";


/**
 * ColReorder version
 *  @constant  VERSION
 *  @type      String
 *  @default   1.0.2
 */
ColReorder.VERSION = "1.0.2";
ColReorder.prototype.VERSION = ColReorder.VERSION;





/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Initialisation
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*
 * Register a new feature with DataTables
 */
if ( typeof $.fn.dataTable == "function" &&
     typeof $.fn.dataTableExt.fnVersionCheck == "function" &&
     $.fn.dataTableExt.fnVersionCheck('1.8.0') )
{
        $.fn.dataTableExt.aoFeatures.push( {
                "fnInit": function( oDTSettings ) {
                        var oTable = oDTSettings.oInstance;
                        if ( typeof oTable._oPluginColReorder == 'undefined' ) {
                                var opts = typeof oDTSettings.oInit.oColReorder != 'undefined' ? 
                                        oDTSettings.oInit.oColReorder : {};
                                oTable._oPluginColReorder = new ColReorder( oDTSettings.oInstance, opts );
                        } else {
                                oTable.oApi._fnLog( oDTSettings, 1, "ColReorder attempted to initialise twice. Ignoring second" );
                        }
                        
                        return null; /* No node to insert */
                },
                "cFeature": "R",
                "sFeature": "ColReorder"
        } );
}
else
{
        alert( "Warning: ColReorder requires DataTables 1.8.0 or greater - www.datatables.net/download");
}

})(jQuery, window, document);