var Qs_Form_OrderSelect = qs.createObject();

Qs_Form_OrderSelect.prototype = 
{
    initialize: function (opt)
    {
        for (var i in opt) {
            this[i] = opt[i];
        }
        var elements = document.getElementsByName(this.name + '[]');
        if (!elements.length) {
            alert('Select with name "' + this.name + '" not found');
            return false;
        } else {
            this.hiddenElement = elements[0];
        }
        elements = document.getElementsByName('_' + this.name + '[]');
        if (!elements.length) {
            alert('Select with name "' + this.name + '" not found');
            return false;
        } else {
            this.element = elements[0];
        }
        
        this.btnUp = document.getElementById(this.name + '_move_up');
        this.btnDown = document.getElementById(this.name + '_move_down');
        
        var obj = this;
        this.btnUp.onclick = function() {
            obj.onUp();
        };
        this.btnDown.onclick = function() {
            obj.onDown();
        };
    },
    
    switchOptions: function (select, topIndex, currentIndex)
    {
        var tmp = select.options[topIndex].text;
        select.options[topIndex].text = select.options[currentIndex].text;
        select.options[topIndex].label = select.options[currentIndex].label;
        select.options[currentIndex].text = tmp;
        select.options[currentIndex].label = tmp;
        
        var tmpValue = select.options[topIndex].value;
        select.options[topIndex].value = select.options[currentIndex].value;
        select.options[currentIndex].value = tmpValue;
        
        var selected = select.options[topIndex].selected;
        select.options[topIndex].selected = select.options[currentIndex].selected;
        select.options[currentIndex].selected = selected;
    },
    
    onUp: function ()
    {
        var topIndex = null;
        for (var i = 0; i < this.element.options.length; i++) {
            if (this.element.options[i].selected && topIndex !== null && !this.element.options[topIndex].selected) {
                this.switchOptions(this.element, topIndex, i);
                this.switchOptions(this.hiddenElement, topIndex, i);
            }
            topIndex = i;
        }
    },
    
    onDown: function ()
    {
        var topIndex = null;
        for (var i = this.element.options.length -1; i >= 0; i--) {
            if (this.element.options[i].selected && topIndex !== null && !this.element.options[topIndex].selected) {
                this.switchOptions(this.element, topIndex, i);
                this.switchOptions(this.hiddenElement, topIndex, i);
            }
            topIndex = i;
        }
    }
};

function initFormOrderSelect(name)
{
    var select = new Qs_Form_OrderSelect({name: name});
}