Autocompleter.DWR = Class.create();
Autocompleter.DWR.prototype = Object.extend(new Autocompleter.Base(), {
    initialize: function(element, update, populator, options) {
        this.baseInitialize(element, update, options);
        this.options.array = new Array(0);
        this.populator = populator;
        if (this.options.afterUpdateElement ) {
             this.afterUpdateCallback = this.options.afterUpdateElement;
             this.options.afterUpdateElement = this.afterUpdateElement.bind(this);
        }
    },

    // called by the autocompleter on an event.
    getUpdatedChoices: function() {
        this.populator(this, this.getToken()); // this is the populator specified in the constructor.
    },

    afterUpdateElement: function(element,selectedElement) {
        this.afterUpdateCallback(element, selectedElement,this.options.array[this.index]);
	},

    // should be called by the populator (specified in the constructor)
    setChoices: function(array) {
        this.options.array = array;
        this.updateChoices(this.options.selector(this));
    },

    setOptions: function(options) {
        this.options = Object.extend({
            choices: 10,
            partialSearch: true,
            partialChars: 2,
            ignoreCase: true,
            fullSearch: false,
            selector: function(instance) {
                var ret       = []; // Beginning matches
                var partial   = []; // Inside matches
                var entry     = instance.getToken();
                var count     = 0;
                var valueSelector = instance.options.valueSelector;

                for (var i = 0; i < instance.options.array.length &&
                        ret.length < instance.options.choices ; i++) {
                    var elem = valueSelector(instance.options.array[i]);
                    var foundPos = instance.options.ignoreCase ?
                            elem.toLowerCase().indexOf(entry.toLowerCase()) :
                            elem.indexOf(entry);

                    while (foundPos != -1) {
                        if (foundPos == 0 && elem.length != entry.length) {
                            ret.push("<li><strong>" + elem.substr(0, entry.length) + "</strong>" + elem.substr(entry.length) + "</li>");
                            break;
                        } else if (entry.length >= instance.options.partialChars && instance.options.partialSearch && foundPos != -1) {
                            if (instance.options.fullSearch || /\s/.test(elem.substr(foundPos-1,1))) {
                                partial.push("<li>" + elem.substr(0, foundPos) + "<strong>" + elem.substr(foundPos, entry.length) + "</strong>" + elem.substr(foundPos + entry.length) + "</li>");
                                break;
                            }
                        }
                        foundPos = instance.options.ignoreCase ?
                                elem.toLowerCase().indexOf(entry.toLowerCase(), foundPos  + 1) :
                                elem.indexOf(entry, foundPos + 1);
                    }
                }
                if (partial.length)
                    ret = ret.concat(partial.slice(0, instance.options.choices - ret.length))


				return "<ul>" + ret.join('') + "</ul>";
            },

            valueSelector: function(object){ return object; }
        }, options || {});
    }
});