(function ($) {
    $.fn.selectChain = function (options) {
        var pristup=0; // dodelano - pri prvnim pristupu nedojde k volani ajaxu
        var defaults = {
            key: "id",
            value: "label"
        };
        
        var settings = $.extend({}, defaults, options);
        
        if (!(settings.target instanceof $)) settings.target = $(settings.target);
        
        return this.each(function () {
            var $$ = $(this);
            
            $$.change(function () {
                
                if(pristup>0){
                var data = null;
                if (typeof settings.data == 'string') {
                    data = settings.data + '&' + this.name + '=' + $$.val();
                } else if (typeof settings.data == 'object') {
                    data = settings.data;
                    data[this.name] = $$.val();
                }
                
                //settings.target.empty();
                //settings.target.html("<option value='x'>-- vyberte podtyp --</option>");
                settings.target.addClass("noDisplay");
                
                $.ajax({
                    url: settings.url,
                    data: data,
                    type: (settings.type || 'get'),
                    dataType: 'json',
                    success: function (j) {
                        var options = [], i = 0, o = null;
                        if(j.length){
                        o = document.createElement("OPTION");
                        o.value = "x";
                        o.text = "- vyberte podtyp -";
                        settings.target.get(0).options[0] = o;
                        }
                        
                        for (i = 1; i < j.length+1; i++) {
                            // required to get around IE bug (http://support.microsoft.com/?scid=kb%3Ben-us%3B276228)
                            o = document.createElement("OPTION");
                            o.value = typeof j[i-1] == 'object' ? j[i-1][settings.key] : j[i-1];
                            o.text = typeof j[i-1] == 'object' ? j[i-1][settings.value] : j[i-1];
                            settings.target.get(0).options[i] = o;
                        }
                        
                        if(j.length){settings.target.removeClass("noDisplay");}else{settings.target.addClass("noDisplay");}
                        
                
			// hand control back to browser for a moment
			setTimeout(function () {
			    settings.target
                                .find('option:first')
                                .attr('selected', 'selected')
                                .parent('select')
                                .trigger('change');
			}, 0);
                    },
                    error: function (xhr, desc, er) {
                        // add whatever debug you want here.
			                  //alert("an error occurred xhr:"+xhr+", desc:"+desc+", error"+er);
                    }
                });
                
                } //pristup
                
                pristup=pristup+1;
                
            });
            
        });
    };
})(jQuery);