addEvent(window, "load", sortables_init);

var SORT_COLUMN_INDEX;

function sortables_init() 
{
    // Find all tables with class sortable and make them sortable
    if (!document.getElementsByTagName)
        return;
    tbls = document.getElementsByTagName("table");
    for (ti=0;ti<tbls.length;ti++)
    {
        thisTbl = tbls[ti];
        if (((' '+thisTbl.className+' ').indexOf("sortable") != -1) && (thisTbl.id))
        {
            //initTable(thisTbl.id);
            ts_makeSortable(thisTbl);
        }
    }
}

function ts_makeSortable(table) 
{
    if (table.rows && table.rows.length > 0)
    {
        var firstRow = table.rows[0];
    }
    if (!firstRow)
        return;

    // We have a first row: assume it's the header, and make its contents clickable links
    for (var i=0;i<firstRow.cells.length;i++)
    {
        var cell = firstRow.cells[i];
        var txt = ts_getInnerText(cell);
        cell.innerHTML = '<a href="#" class="sortheader" '+ 
                         'onclick="ts_resortTable(this, '+i+');return false;">' + 
                         txt+'<span class="sortarrow">&nbsp;&nbsp;&nbsp;</span></a>';
    }
}

function ts_getInnerText(el) 
{
    if (["SCRIPT", "IMG"].indexOf(el.tagName) != -1)
        return "";

    if (typeof el == "string")
        return el;
    if (typeof el == "undefined")
        return el;
    
    if (el.value)
        return el.value;
    if (el.innerText)
        return el.innerText;    //Not needed but it is faster
    
    var str = "";
    var cs  = el.childNodes;
    var l   = cs.length;
    for (var i = 0; i < l; i++)
    {
        switch (cs[i].nodeType)
        {
        case 1: //ELEMENT_NODE
            str += ts_getInnerText(cs[i]);
            break;
        case 3: //TEXT_NODE
            str += cs[i].nodeValue;
            break;
        }
    }
    return str;
}

function ts_resortTable(lnk,clid) 
{
    // get the span
    var span;
    for (var ci=0;ci<lnk.childNodes.length;ci++)
    {
        if (lnk.childNodes[ci].tagName && lnk.childNodes[ci].tagName.toLowerCase() == 'span')
            span = lnk.childNodes[ci];
    }
    var spantext = ts_getInnerText(span);
    var td       = lnk.parentNode;
    var column   = clid || td.cellIndex;
    var table    = getParent(td,'TABLE');  
    // Work out a type for the column
    if (table.rows.length <= 1)
        return;
    var itm = "";
    for (a=1; a<table.rows.length && itm == ""; a++)
    {
       itm = ts_getInnerText(table.rows[a].cells[column]);
    }
    sortfn = ts_sort_caseinsensitive;
    if (itm.match(/^\d\d[\/-]\d\d[\/-]\d\d\d\d$/))
        sortfn = ts_sort_date;
    if (itm.match(/^\d\d[\/-]\d\d[\/-]\d\d$/))
        sortfn = ts_sort_date;
    if (itm.match(/^[£$]/))
        sortfn = ts_sort_currency;
    if (itm.match(/^[\d\.]+$/))
        sortfn = ts_sort_numeric;
    SORT_COLUMN_INDEX = column;
    var firstRow = new Array();
    var newRows = new Array();
    for (i=0;i<table.rows[0].length;i++)
        firstRow[i] = table.rows[0][i];
    for (j=1;j<table.rows.length;j++)
        newRows[j-1] = table.rows[j];

    newRows.sort(sortfn);

    if (span.getAttribute("sortdir") == 'down')
    {
        ARROW = '&nbsp;&nbsp;&uarr;';
        newRows.reverse();
        span.setAttribute('sortdir','up');
    } 
    else
    {
        ARROW = '&nbsp;&nbsp;&darr;';
        span.setAttribute('sortdir','down');
    }
    
    // We appendChild rows that already exist to the tbody, so it moves them rather than creating new ones
    // don't do sortbottom rows
    for (i=0;i<newRows.length;i++)
    {
        if (!newRows[i].className || (newRows[i].className && (newRows[i].className.indexOf('sortbottom') == -1))) 
            table.tBodies[0].appendChild(newRows[i]);
    }
    // do sortbottom rows only
    for (i=0;i<newRows.length;i++)
    {
        if (newRows[i].className && (newRows[i].className.indexOf('sortbottom') != -1)) 
            table.tBodies[0].appendChild(newRows[i]);
    }
    
    // Delete any other arrows there may be showing
    var allspans = document.getElementsByTagName("span");
    for (var ci=0;ci<allspans.length;ci++)
    {
        if (allspans[ci].className == 'sortarrow')
        {
            if (getParent(allspans[ci],"table") == getParent(lnk,"table")) // in the same table as us?
            {
                allspans[ci].innerHTML = '&nbsp;&nbsp;&nbsp;';
            }
        }
    }
    span.innerHTML = ARROW;
}

function getParent(el, pTagName) 
{
    if (el == null) 
        return null;
    else if (el.nodeType == 1 && el.tagName.toLowerCase() == pTagName.toLowerCase())    // Gecko bug, supposed to be uppercase
        return el;
    else
        return getParent(el.parentNode, pTagName);
}
function ts_sort_date(a,b) 
{
    // y2k notes: two digit years less than 50 are treated as 20XX, greater than 50 are treated as 19XX
    aa = ts_getInnerText(a.cells[SORT_COLUMN_INDEX]);
    bb = ts_getInnerText(b.cells[SORT_COLUMN_INDEX]);
    if (aa.length == 10)
    {
        dt1 = aa.substr(6,4)+aa.substr(3,2)+aa.substr(0,2);
    } 
    else
    {
        yr = aa.substr(6,2);
        if (parseInt(yr) < 50)
        {
            yr = '20'+yr;
        } 
        else
        {
            yr = '19'+yr;
        }
        dt1 = yr+aa.substr(3,2)+aa.substr(0,2);
    }
    if (bb.length == 10)
    {
        dt2 = bb.substr(6,4)+bb.substr(3,2)+bb.substr(0,2);
    } 
    else
    {
        yr = bb.substr(6,2);
        if (parseInt(yr) < 50)
        {
            yr = '20'+yr;
        }
        else
        {
            yr = '19'+yr;
        }
        dt2 = yr+bb.substr(3,2)+bb.substr(0,2);
    }
    if (dt1==dt2) 
        return 0;
    if (dt1<dt2) 
        return -1;
    return 1;
}

function ts_sort_currency(a,b) 
{ 
    aa = ts_getInnerText(a.cells[SORT_COLUMN_INDEX]).replace(/[^0-9.]/g,'');
    bb = ts_getInnerText(b.cells[SORT_COLUMN_INDEX]).replace(/[^0-9.]/g,'');
    return parseFloat(aa) - parseFloat(bb);
}

function ts_sort_numeric(a,b) 
{ 
    aa = parseFloat(ts_getInnerText(a.cells[SORT_COLUMN_INDEX]));
    if (isNaN(aa)) 
        aa = 0;
    bb = parseFloat(ts_getInnerText(b.cells[SORT_COLUMN_INDEX])); 
    if (isNaN(bb)) 
        bb = 0;
    return aa-bb;
}

function ts_sort_caseinsensitive(a,b) 
{
    aa = ts_getInnerText(a.cells[SORT_COLUMN_INDEX]).toLowerCase();
    bb = ts_getInnerText(b.cells[SORT_COLUMN_INDEX]).toLowerCase();
    if (aa==bb) 
        return 0;
    if (aa<bb) 
        return -1;
    return 1;
}

function ts_sort_default(a,b) 
{
    aa = ts_getInnerText(a.cells[SORT_COLUMN_INDEX]);
    bb = ts_getInnerText(b.cells[SORT_COLUMN_INDEX]);
    if (aa==bb) 
        return 0;
    if (aa<bb) 
        return -1;
    return 1;
}


function addEvent(elm, evType, fn, useCapture)
// addEvent and removeEvent
// cross-browser event handling for IE5+,  NS6 and Mozilla
// By Scott Andrew
{
    if (elm.addEventListener)
    {
        elm.addEventListener(evType, fn, useCapture);
        return true;
    } 
    else if (elm.attachEvent)
    {
        var r = elm.attachEvent("on"+evType, fn);
        return r;
    } 
    else
    {
        alert("Handler could not be removed");
    }
}