var nttgAllText = "*";
// Attach the filter to a table. filterRow specifies the rownumber at which the filter should be inserted.
function attachFilter(table, filterRow) {
    table.filterRow = filterRow;
    // Check if the table has any rows. If not, do nothing
    if (table.rows.length > 0) {
        // Insert the filterrow on header and add cells whith drowdowns.
        var filterRow = table.tHead.insertRow(table.filterRow);
        for (var i = 0; i < table.rows[table.filterRow + 1].cells.length; i++) {
            var c = document.createElement("TD");
            //table.rows[table.filterRow].appendChild(c);

            filterRow.appendChild(c);
            if (table.tHead.rows[0].cells[i].className != "noFilter") {
                var opt = document.createElement("select");
                opt.onchange = filter;

                c.appendChild(opt);
            }
        }
        // Set the functions
        table.fillFilters = fillFilters;
        table.inFilter = inFilter;
        table.buildFilter = buildFilter;
        table.showAll = showAll;
        table.alternateRowColorTable = alternateRowColorTable;
        table.detachFilter = detachFilter;
        table.filterElements = new Array();

        // Fill the filters
        table.fillFilters();
        table.filterEnabled = true;
    }
}

function detachFilter() {
    if (this.filterEnabled) {
        // Remove the filter
        this.showAll();
        this.deleteRow(this.filterRow);
        this.filterEnabled = false;
    }
}

// Checks if a column is filtered
function inFilter(col) {
    for (var i = 0; i < this.filterElements.length; i++) {
        if (this.filterElements[i].index == col)
            return true;
    }
    return false;
}

// Fills the filters for columns which are not fiiltered
function fillFilters() {
    for (var col = 0; col < this.rows[this.filterRow].cells.length; col++) {
        if (!this.inFilter(col)) {
            //alert(col.className)
            //alert(this.tHead.rows[0].cells[col].className)
            if (this.tHead.rows[0].cells[col].className != "noFilter") {
                this.buildFilter(col, nttgAllText);
            }
        }
    }
}

// Fills the columns dropdown box. 
// setValue is the value which the dropdownbox should have one filled. 
// If the value is not suplied, the first item is selected
function buildFilter(col, setValue) {
    // Get a reference to the dropdownbox.
    var opt = this.rows[this.filterRow].cells[col].firstChild;

    // remove all existing items
    while (opt.length > 0)
        opt.remove(0);

    var values = new Array();

    // put all relevant strings in the values array.
    for (var i = this.filterRow + 1; i < this.rows.length; i++) {
        var row = this.rows[i];
        if (row.style.display != "none" && row.className != "noFilter") {
            values.push(row.cells[col].innerHTML.toUpperCase());
        }
    }
    values.sort();

    //add each unique string to the dopdownbox
    var value;
    for (var i = 0; i < values.length; i++) {
        if (values[i].toUpperCase() != value) {
            value = values[i].toUpperCase();
            opt.options.add(new Option(values[i], value));
        }
    }

    opt.options.add(new Option(nttgAllText, nttgAllText), 0);

    if (setValue != undefined)
        opt.value = setValue;
    else
        opt.options[0].selected = true;
}

// This function is called when a dropdown box changes
function filter() {

    var table = this; // 'this' is a reference to the dropdownbox which changed
    while (table.tagName.toUpperCase() != "TABLE")
        table = table.parentNode;

    var filterIndex = this.parentNode.cellIndex; // The column number of the column which should be filtered
    var filterText = table.rows[table.filterRow].cells[filterIndex].firstChild.value;

    // First check if the column is allready in the filter.
    var bFound = false;

    for (var i = 0; i < table.filterElements.length; i++) {
        if (table.filterElements[i].index == filterIndex) {
            bFound = true;
            // If the new value is '(all') this column is removed from the filter.
            if (filterText == nttgAllText) {
                table.filterElements.splice(i, 1);
            }
            else {
                table.filterElements[i].filter = filterText;
            }
            break;
        }
    }
    if (!bFound) {
        // the column is added to the filter
        var obj = new Object();
        obj.filter = filterText;
        obj.index = filterIndex;
        table.filterElements.push(obj);
    }

    // first set all rows to be displayed
    table.showAll();

    // the filter ou the right rows.
    for (var i = 0; i < table.filterElements.length; i++) {
        // First fill the dropdown box for this column
        table.buildFilter(table.filterElements[i].index, table.filterElements[i].filter);
        // Apply the filter
        for (var j = table.filterRow + 1; j < table.rows.length; j++) {
            var row = table.rows[j];

            if (table.style.display != "none" && row.className != "noFilter") {
                if (table.filterElements[i].filter != row.cells[table.filterElements[i].index].innerHTML.toUpperCase()) {
                    row.style.display = "none";
                }
            }
        }
    }
    // Fill the dropdownboxes for the remaining columns.
    table.fillFilters();
    table.alternateRowColorTable();
}

function showAll() {
    for (var i = this.filterRow + 1; i < this.rows.length; i++) {
        this.rows[i].style.display = "";
    }
}

function alternateRowColorTable() {
    if (document.getElementsByTagName) {
        var rows = this.getElementsByTagName("tr");
        var j = 0;

        for (i = 0; i < rows.length; i++) {
            //manipulate rows if row is displayed
            if (rows[i].style.display != "none") {
                if (j % 2 == 0) {
                    rows[i].className = "even";
                } else {
                    rows[i].className = "odd";
                }

                j++;
            }
        }
    }
}