typeahead.js

/*!
 * typeahead.js 0.9.4
 * https://github.com/twitter/typeahead
 * Copyright 2013 Twitter, Inc. and other contributors; Licensed MIT
 */

(function($) {
    var VERSION = "0.9.4";
    var utils = {
        isMsie: function() {
            var match = /(msie) ([\w.]+)/i.exec(navigator.userAgent);
            return match ? parseInt(match[2], 10) : false;
        },
        isBlankString: function(str) {
            return !str || /^\s*$/.test(str);
        },
        escapeRegExChars: function(str) {
            return str.replace(/[\-\[\]\/\{\}\(\)\*\+\?\.\\\^\$\|]/g, "\\$&");
        },
        isString: function(obj) {
            return typeof obj === "string";
        },
        isNumber: function(obj) {
            return typeof obj === "number";
        },
        isArray: $.isArray,
        isFunction: $.isFunction,
        isObject: $.isPlainObject,
        isUndefined: function(obj) {
            return typeof obj === "undefined";
        },
        bind: $.proxy,
        bindAll: function(obj) {
            var val;
            for (var key in obj) {
                $.isFunction(val = obj[key]) && (obj[key] = $.proxy(val, obj));
            }
        },
        indexOf: function(haystack, needle) {
            for (var i = 0; i < haystack.length; i++) {
                if (haystack[i] === needle) {
                    return i;
                }
            }
            return -1;
        },
        each: $.each,
        map: $.map,
        filter: $.grep,
        every: function(obj, test) {
            var result = true;
            if (!obj) {
                return result;
            }
            $.each(obj, function(key, val) {
                if (!(result = test.call(null, val, key, obj))) {
                    return false;
                }
            });
            return !!result;
        },
        some: function(obj, test) {
            var result = false;
            if (!obj) {
                return result;
            }
            $.each(obj, function(key, val) {
                if (result = test.call(null, val, key, obj)) {
                    return false;
                }
            });
            return !!result;
        },
        mixin: $.extend,
        getUniqueId: function() {
            var counter = 0;
            return function() {
                return counter++;
            };
        }(),
        defer: function(fn) {
            setTimeout(fn, 0);
        },
        debounce: function(func, wait, immediate) {
            var timeout, result;
            return function() {
                var context = this, args = arguments, later, callNow;
                later = function() {
                    timeout = null;
                    if (!immediate) {
                        result = func.apply(context, args);
                    }
                };
                callNow = immediate && !timeout;
                clearTimeout(timeout);
                timeout = setTimeout(later, wait);
                if (callNow) {
                    result = func.apply(context, args);
                }
                return result;
            };
        },
        throttle: function(func, wait) {
            var context, args, timeout, result, previous, later;
            previous = 0;
            later = function() {
                previous = new Date();
                timeout = null;
                result = func.apply(context, args);
            };
            return function() {
                var now = new Date(), remaining = wait - (now - previous);
                context = this;
                args = arguments;
                if (remaining <= 0) {
                    clearTimeout(timeout);
                    timeout = null;
                    previous = now;
                    result = func.apply(context, args);
                } else if (!timeout) {
                    timeout = setTimeout(later, remaining);
                }
                return result;
            };
        },
        tokenizeQuery: function(str) {
            return $.trim(str).toLowerCase().split(/[\s]+/);
        },
        tokenizeText: function(str) {
            return $.trim(str).toLowerCase().split(/[\s\-_]+/);
        },
        getProtocol: function() {
            return location.protocol;
        },
        noop: function() {}
    };
    var EventTarget = function() {
        var eventSplitter = /\s+/;
        return {
            on: function(events, callback) {
                var event;
                if (!callback) {
                    return this;
                }
                this._callbacks = this._callbacks || {};
                events = events.split(eventSplitter);
                while (event = events.shift()) {
                    this._callbacks[event] = this._callbacks[event] || [];
                    this._callbacks[event].push(callback);
                }
                return this;
            },
            trigger: function(events, data) {
                var event, callbacks;
                if (!this._callbacks) {
                    return this;
                }
                events = events.split(eventSplitter);
                while (event = events.shift()) {
                    if (callbacks = this._callbacks[event]) {
                        for (var i = 0; i < callbacks.length; i += 1) {
                            callbacks[i].call(this, {
                                type: event,
                                data: data
                            });
                        }
                    }
                }
                return this;
            }
        };
    }();
    var EventBus = function() {
        var namespace = "typeahead:";
        function EventBus(o) {
            if (!o || !o.el) {
                $.error("EventBus initialized without el");
            }
            this.$el = $(o.el);
        }
        utils.mixin(EventBus.prototype, {
            trigger: function(type) {
                var args = [].slice.call(arguments, 1);
                this.$el.trigger(namespace + type, args);
            }
        });
        return EventBus;
    }();
    var PersistentStorage = function() {
        var ls, methods;
        try {
            ls = window.localStorage;
            ls.setItem("~~~", "!");
            ls.removeItem("~~~");
        } catch (err) {
            ls = null;
        }
        function PersistentStorage(namespace) {
            this.prefix = [ "__", namespace, "__" ].join("");
            this.ttlKey = "__ttl__";
            this.keyMatcher = new RegExp("^" + this.prefix);
        }
        if (ls && window.JSON) {
            methods = {
                _prefix: function(key) {
                    return this.prefix + key;
                },
                _ttlKey: function(key) {
                    return this._prefix(key) + this.ttlKey;
                },
                get: function(key) {
                    if (this.isExpired(key)) {
                        this.remove(key);
                    }
                    return decode(ls.getItem(this._prefix(key)));
                },
                set: function(key, val, ttl) {
                    if (utils.isNumber(ttl)) {
                        ls.setItem(this._ttlKey(key), encode(now() + ttl));
                    } else {
                        ls.removeItem(this._ttlKey(key));
                    }
                    return ls.setItem(this._prefix(key), encode(val));
                },
                remove: function(key) {
                    ls.removeItem(this._ttlKey(key));
                    ls.removeItem(this._prefix(key));
                    return this;
                },
                clear: function() {
                    var i, key, keys = [], len = ls.length;
                    for (i = 0; i < len; i++) {
                        if ((key = ls.key(i)).match(this.keyMatcher)) {
                            keys.push(key.replace(this.keyMatcher, ""));
                        }
                    }
                    for (i = keys.length; i--; ) {
                        this.remove(keys[i]);
                    }
                    return this;
                },
                isExpired: function(key) {
                    var ttl = decode(ls.getItem(this._ttlKey(key)));
                    return utils.isNumber(ttl) && now() > ttl ? true : false;
                }
            };
        } else {
            methods = {
                get: utils.noop,
                set: utils.noop,
                remove: utils.noop,
                clear: utils.noop,
                isExpired: utils.noop
            };
        }
        utils.mixin(PersistentStorage.prototype, methods);
        return PersistentStorage;
        function now() {
            return new Date().getTime();
        }
        function encode(val) {
            return JSON.stringify(utils.isUndefined(val) ? null : val);
        }
        function decode(val) {
            return JSON.parse(val);
        }
    }();
    var RequestCache = function() {
        function RequestCache(o) {
            utils.bindAll(this);
            o = o || {};
            this.sizeLimit = o.sizeLimit || 10;
            this.cache = {};
            this.cachedKeysByAge = [];
        }
        utils.mixin(RequestCache.prototype, {
            get: function(url) {
                return this.cache[url];
            },
            set: function(url, resp) {
                var requestToEvict;
                if (this.cachedKeysByAge.length === this.sizeLimit) {
                    requestToEvict = this.cachedKeysByAge.shift();
                    delete this.cache[requestToEvict];
                }
                this.cache[url] = resp;
                this.cachedKeysByAge.push(url);
            }
        });
        return RequestCache;
    }();
    var Transport = function() {
        var pendingRequestsCount = 0, pendingRequests = {}, maxPendingRequests, requestCache;
        function Transport(o) {
            utils.bindAll(this);
            o = utils.isString(o) ? {
                url: o
            } : o;
            requestCache = requestCache || new RequestCache();
            maxPendingRequests = utils.isNumber(o.maxParallelRequests) ? o.maxParallelRequests : maxPendingRequests || 6;
            this.url = o.url;
            this.wildcard = o.wildcard || "%QUERY";
            this.filter = o.filter;
            this.replace = o.replace;
            this.ajaxSettings = {
                type: "get",
                cache: o.cache,
                timeout: o.timeout,
                dataType: o.dataType || "json",
                beforeSend: o.beforeSend
            };
            this._get = (/^throttle$/i.test(o.rateLimitFn) ? utils.throttle : utils.debounce)(this._get, o.rateLimitWait || 300);
        }
        utils.mixin(Transport.prototype, {
            _get: function(url, cb) {
                var that = this;
                if (belowPendingRequestsThreshold()) {
                    this._sendRequest(url).done(done);
                } else {
                    this.onDeckRequestArgs = [].slice.call(arguments, 0);
                }
                function done(resp) {
                    var data = that.filter ? that.filter(resp) : resp;
                    cb && cb(data);
                    requestCache.set(url, resp);
                }
            },
            _sendRequest: function(url) {
                var that = this, jqXhr = pendingRequests[url];
                if (!jqXhr) {
                    incrementPendingRequests();
                    jqXhr = pendingRequests[url] = $.ajax(url, this.ajaxSettings).always(always);
                }
                return jqXhr;
                function always() {
                    decrementPendingRequests();
                    pendingRequests[url] = null;
                    if (that.onDeckRequestArgs) {
                        that._get.apply(that, that.onDeckRequestArgs);
                        that.onDeckRequestArgs = null;
                    }
                }
            },
            get: function(query, cb) {
                var that = this, encodedQuery = encodeURIComponent(query || ""), url, resp;
                cb = cb || utils.noop;
                url = this.replace ? this.replace(this.url, encodedQuery) : this.url.replace(this.wildcard, encodedQuery);
                if (resp = requestCache.get(url)) {
                    utils.defer(function() {
                        cb(that.filter ? that.filter(resp) : resp);
                    });
                } else {
                    this._get(url, cb);
                }
                return !!resp;
            }
        });
        return Transport;
        function incrementPendingRequests() {
            pendingRequestsCount++;
        }
        function decrementPendingRequests() {
            pendingRequestsCount--;
        }
        function belowPendingRequestsThreshold() {
            return pendingRequestsCount < maxPendingRequests;
        }
    }();
    var Dataset = function() {
        var keys = {
            thumbprint: "thumbprint",
            protocol: "protocol",
            itemHash: "itemHash",
            adjacencyList: "adjacencyList"
        };
        function Dataset(o) {
            utils.bindAll(this);
            if (utils.isString(o.template) && !o.engine) {
                $.error("no template engine specified");
            }
            if (!o.local && !o.prefetch && !o.remote) {
                $.error("one of local, prefetch, or remote is required");
            }
            this.name = o.name || utils.getUniqueId();
            this.limit = o.limit || 5;
            this.minLength = o.minLength || 1;
            this.header = o.header;
            this.footer = o.footer;
            this.valueKey = o.valueKey || "value";
            this.template = compileTemplate(o.template, o.engine, this.valueKey);
            this.render = o.render;
            this.local = o.local;
            this.prefetch = o.prefetch;
            this.remote = o.remote;
            this.itemHash = {};
            this.adjacencyList = {};
            this.storage = o.name ? new PersistentStorage(o.name) : null;
        }
        utils.mixin(Dataset.prototype, {
            _processLocalData: function(data) {
                this._mergeProcessedData(this._processData(data));
            },
            _loadPrefetchData: function(o) {
                var that = this, thumbprint = VERSION + (o.thumbprint || ""), storedThumbprint, storedProtocol, storedItemHash, storedAdjacencyList, isExpired, deferred;
                if (this.storage) {
                    storedThumbprint = this.storage.get(keys.thumbprint);
                    storedProtocol = this.storage.get(keys.protocol);
                    storedItemHash = this.storage.get(keys.itemHash);
                    storedAdjacencyList = this.storage.get(keys.adjacencyList);
                }
                isExpired = storedThumbprint !== thumbprint || storedProtocol !== utils.getProtocol();
                o = utils.isString(o) ? {
                    url: o
                } : o;
                o.ttl = utils.isNumber(o.ttl) ? o.ttl : 24 * 60 * 60 * 1e3;
                if (storedItemHash && storedAdjacencyList && !isExpired) {
                    this._mergeProcessedData({
                        itemHash: storedItemHash,
                        adjacencyList: storedAdjacencyList
                    });
                    deferred = $.Deferred().resolve();
                } else {
                    deferred = $.getJSON(o.url).done(processPrefetchData);
                }
                return deferred;
                function processPrefetchData(data) {
                    var filteredData = o.filter ? o.filter(data) : data, processedData = that._processData(filteredData), itemHash = processedData.itemHash, adjacencyList = processedData.adjacencyList;
                    if (that.storage) {
                        that.storage.set(keys.itemHash, itemHash, o.ttl);
                        that.storage.set(keys.adjacencyList, adjacencyList, o.ttl);
                        that.storage.set(keys.thumbprint, thumbprint, o.ttl);
                        that.storage.set(keys.protocol, utils.getProtocol(), o.ttl);
                    }
                    that._mergeProcessedData(processedData);
                }
            },
            _transformDatum: function(datum) {
                var value = utils.isString(datum) ? datum : datum[this.valueKey], tokens = datum.tokens || utils.tokenizeText(value), item = {
                    value: value,
                    tokens: tokens
                };
                if (utils.isString(datum)) {
                    item.datum = {};
                    item.datum[this.valueKey] = datum;
                } else {
                    item.datum = datum;
                }
                item.tokens = utils.filter(item.tokens, function(token) {
                    return !utils.isBlankString(token);
                });
                item.tokens = utils.map(item.tokens, function(token) {
                    return token.toLowerCase();
                });
                return item;
            },
            _processData: function(data) {
                var that = this, itemHash = {}, adjacencyList = {};
                utils.each(data, function(i, datum) {
                    var item = that._transformDatum(datum), id = utils.getUniqueId(item.value);
                    itemHash[id] = item;
                    utils.each(item.tokens, function(i, token) {
                        var character = token.charAt(0), adjacency = adjacencyList[character] || (adjacencyList[character] = [ id ]);
                        !~utils.indexOf(adjacency, id) && adjacency.push(id);
                    });
                });
                return {
                    itemHash: itemHash,
                    adjacencyList: adjacencyList
                };
            },
            _mergeProcessedData: function(processedData) {
                var that = this;
                utils.mixin(this.itemHash, processedData.itemHash);
                utils.each(processedData.adjacencyList, function(character, adjacency) {
                    var masterAdjacency = that.adjacencyList[character];
                    that.adjacencyList[character] = masterAdjacency ? masterAdjacency.concat(adjacency) : adjacency;
                });
            },
            _getLocalSuggestions: function(terms) {
                var that = this, firstChars = [], lists = [], shortestList, suggestions = [];
                utils.each(terms, function(i, term) {
                    var firstChar = term.charAt(0);
                    !~utils.indexOf(firstChars, firstChar) && firstChars.push(firstChar);
                });
                utils.each(firstChars, function(i, firstChar) {
                    var list = that.adjacencyList[firstChar];
                    if (!list) {
                        return false;
                    }
                    lists.push(list);
                    if (!shortestList || list.length < shortestList.length) {
                        shortestList = list;
                    }
                });
                if (lists.length < firstChars.length) {
                    return [];
                }
                utils.each(shortestList, function(i, id) {
                    var item = that.itemHash[id], isCandidate, isMatch;
                    isCandidate = utils.every(lists, function(list) {
                        return ~utils.indexOf(list, id);
                    });
                    isMatch = isCandidate && utils.every(terms, function(term) {
                        return utils.some(item.tokens, function(token) {
                            return token.indexOf(term) === 0;
                        });
                    });
                    isMatch && suggestions.push(item);
                });
                return suggestions;
            },
            initialize: function() {
                var deferred;
                this.local && this._processLocalData(this.local);
                this.transport = this.remote ? new Transport(this.remote) : null;
                deferred = this.prefetch ? this._loadPrefetchData(this.prefetch) : $.Deferred().resolve();
                this.local = this.prefetch = this.remote = null;
                this.initialize = function() {
                    return deferred;
                };
                return deferred;
            },
            getSuggestions: function(query, cb) {
                var that = this, terms, suggestions, cacheHit = false;
                if (query.length < this.minLength) {
                    return;
                }
                terms = utils.tokenizeQuery(query);
                suggestions = this._getLocalSuggestions(terms).slice(0, this.limit);
                if (suggestions.length < this.limit && this.transport) {
                    cacheHit = this.transport.get(query, processRemoteData);
                }
                !cacheHit && cb && cb(suggestions);
                function processRemoteData(data) {
                    suggestions = suggestions.slice(0);
                    utils.each(data, function(i, datum) {
                        var item = that._transformDatum(datum), isDuplicate;
                        isDuplicate = utils.some(suggestions, function(suggestion) {
                            return item.value === suggestion.value;
                        });
                        !isDuplicate && suggestions.push(item);
                        return suggestions.length < that.limit;
                    });
                    cb && cb(suggestions);
                }
            }
        });
        return Dataset;
        function compileTemplate(template, engine, valueKey) {
            var renderFn, compiledTemplate;
            if (utils.isFunction(template)) {
                renderFn = template;
            } else if (utils.isString(template)) {
                compiledTemplate = engine.compile(template);
                renderFn = utils.bind(compiledTemplate.render, compiledTemplate);
            } else {
                renderFn = function(context) {
                    return "<p>" + context[valueKey] + "</p>";
                };
            }
            return renderFn;
        }
    }();
    var InputView = function() {
        function InputView(o) {
            var that = this;
            utils.bindAll(this);
            this.specialKeyCodeMap = {
                9: "tab",
                27: "esc",
                37: "left",
                39: "right",
                13: "enter",
                38: "up",
                40: "down"
            };
            this.$hint = $(o.hint);
            this.$input = $(o.input).on("blur.tt", this._handleBlur).on("focus.tt", this._handleFocus).on("keydown.tt", this._handleSpecialKeyEvent);
            if (!utils.isMsie()) {
                this.$input.on("input.tt", this._compareQueryToInputValue);
            } else {
                this.$input.on("keydown.tt keypress.tt cut.tt paste.tt", function($e) {
                    if (that.specialKeyCodeMap[$e.which || $e.keyCode]) {
                        return;
                    }
                    utils.defer(that._compareQueryToInputValue);
                });
            }
            this.query = this.$input.val();
            this.$overflowHelper = buildOverflowHelper(this.$input);
        }
        utils.mixin(InputView.prototype, EventTarget, {
            _handleFocus: function() {
                this.trigger("focused");
            },
            _handleBlur: function() {
                this.trigger("blured");
            },
            _handleSpecialKeyEvent: function($e) {
                var keyName = this.specialKeyCodeMap[$e.which || $e.keyCode];
                keyName && this.trigger(keyName + "Keyed", $e);
            },
            _compareQueryToInputValue: function() {
                var inputValue = this.getInputValue(), isSameQuery = compareQueries(this.query, inputValue), isSameQueryExceptWhitespace = isSameQuery ? this.query.length !== inputValue.length : false;
                if (isSameQueryExceptWhitespace) {
                    this.trigger("whitespaceChanged", {
                        value: this.query
                    });
                } else if (!isSameQuery) {
                    this.trigger("queryChanged", {
                        value: this.query = inputValue
                    });
                }
            },
            destroy: function() {
                this.$hint.off(".tt");
                this.$input.off(".tt");
                this.$hint = this.$input = this.$overflowHelper = null;
            },
            focus: function() {
                this.$input.focus();
            },
            blur: function() {
                this.$input.blur();
            },
            getQuery: function() {
                return this.query;
            },
            setQuery: function(query) {
                this.query = query;
            },
            getInputValue: function() {
                return this.$input.val();
            },
            setInputValue: function(value, silent) {
                this.$input.val(value);
                !silent && this._compareQueryToInputValue();
            },
            getHintValue: function() {
                return this.$hint.val();
            },
            setHintValue: function(value) {
                this.$hint.val(value);
            },
            getLanguageDirection: function() {
                return (this.$input.css("direction") || "ltr").toLowerCase();
            },
            isOverflow: function() {
                this.$overflowHelper.text(this.getInputValue());
                return this.$overflowHelper.width() > this.$input.width();
            },
            isCursorAtEnd: function() {
                var valueLength = this.$input.val().length, selectionStart = this.$input[0].selectionStart, range;
                if (utils.isNumber(selectionStart)) {
                    return selectionStart === valueLength;
                } else if (document.selection) {
                    range = document.selection.createRange();
                    range.moveStart("character", -valueLength);
                    return valueLength === range.text.length;
                }
                return true;
            }
        });
        return InputView;
        function buildOverflowHelper($input) {
            return $("<span></span>").css({
                position: "absolute",
                left: "-9999px",
                visibility: "hidden",
                whiteSpace: "nowrap",
                fontFamily: $input.css("font-family"),
                fontSize: $input.css("font-size"),
                fontStyle: $input.css("font-style"),
                fontVariant: $input.css("font-variant"),
                fontWeight: $input.css("font-weight"),
                wordSpacing: $input.css("word-spacing"),
                letterSpacing: $input.css("letter-spacing"),
                textIndent: $input.css("text-indent"),
                textRendering: $input.css("text-rendering"),
                textTransform: $input.css("text-transform")
            }).insertAfter($input);
        }
        function compareQueries(a, b) {
            a = (a || "").replace(/^\s*/g, "").replace(/\s{2,}/g, " ");
            b = (b || "").replace(/^\s*/g, "").replace(/\s{2,}/g, " ");
            return a === b;
        }
    }();
    var DropdownView = function() {
        var html = {
            suggestionsList: '<span class="tt-suggestions"></span>'
        }, css = {
            suggestionsList: {
                display: "block"
            },
            suggestion: {
                whiteSpace: "nowrap",
                cursor: "pointer"
            },
            suggestionChild: {
                whiteSpace: "normal"
            }
        };
        function DropdownView(o) {
            utils.bindAll(this);
            this.isOpen = false;
            this.isEmpty = true;
            this.isMouseOverDropdown = false;
            this.$menu = $(o.menu).on("mouseenter.tt", this._handleMouseenter).on("mouseleave.tt", this._handleMouseleave).on("click.tt", ".tt-suggestion", this._handleSelection).on("mouseover.tt", ".tt-suggestion", this._handleMouseover);
        }
        utils.mixin(DropdownView.prototype, EventTarget, {
            _handleMouseenter: function() {
                this.isMouseOverDropdown = true;
            },
            _handleMouseleave: function() {
                this.isMouseOverDropdown = false;
            },
            _handleMouseover: function($e) {
                var $suggestion = $($e.currentTarget);
                this._getSuggestions().removeClass("tt-is-under-cursor");
                $suggestion.addClass("tt-is-under-cursor");
            },
            _handleSelection: function($e) {
                var $suggestion = $($e.currentTarget);
                this.trigger("suggestionSelected", extractSuggestion($suggestion));
            },
            _show: function() {
                this.$menu.css("display", "block");
            },
            _hide: function() {
                this.$menu.hide();
            },
            _moveCursor: function(increment) {
                var $suggestions, $cur, nextIndex, $underCursor;
                if (!this.isVisible()) {
                    return;
                }
                $suggestions = this._getSuggestions();
                $cur = $suggestions.filter(".tt-is-under-cursor");
                $cur.removeClass("tt-is-under-cursor");
                nextIndex = $suggestions.index($cur) + increment;
                nextIndex = (nextIndex + 1) % ($suggestions.length + 1) - 1;
                if (nextIndex === -1) {
                    this.trigger("cursorRemoved");
                    return;
                } else if (nextIndex < -1) {
                    nextIndex = $suggestions.length - 1;
                }
                $underCursor = $suggestions.eq(nextIndex).addClass("tt-is-under-cursor");
                this._ensureVisibility($underCursor);
                this.trigger("cursorMoved", extractSuggestion($underCursor));
            },
            _getSuggestions: function() {
                return this.$menu.find(".tt-suggestions > .tt-suggestion");
            },
            _ensureVisibility: function($el) {
                var menuHeight = this.$menu.height() + parseInt(this.$menu.css("paddingTop"), 10) + parseInt(this.$menu.css("paddingBottom"), 10), menuScrollTop = this.$menu.scrollTop(), elTop = $el.position().top, elBottom = elTop + $el.outerHeight(true);
                if (elTop < 0) {
                    this.$menu.scrollTop(menuScrollTop + elTop);
                } else if (menuHeight < elBottom) {
                    this.$menu.scrollTop(menuScrollTop + (elBottom - menuHeight));
                }
            },
            destroy: function() {
                this.$menu.off(".tt");
                this.$menu = null;
            },
            isVisible: function() {
                return this.isOpen && !this.isEmpty;
            },
            closeUnlessMouseIsOverDropdown: function() {
                if (!this.isMouseOverDropdown) {
                    this.close();
                }
            },
            close: function() {
                if (this.isOpen) {
                    this.isOpen = false;
                    this.isMouseOverDropdown = false;
                    this._hide();
                    this.$menu.find(".tt-suggestions > .tt-suggestion").removeClass("tt-is-under-cursor");
                    this.trigger("closed");
                }
            },
            open: function() {
                if (!this.isOpen) {
                    this.isOpen = true;
                    !this.isEmpty && this._show();
                    this.trigger("opened");
                }
            },
            setLanguageDirection: function(dir) {
                var ltrCss = {
                    left: "0",
                    right: "auto"
                }, rtlCss = {
                    left: "auto",
                    right: " 0"
                };
                dir === "ltr" ? this.$menu.css(ltrCss) : this.$menu.css(rtlCss);
            },
            moveCursorUp: function() {
                this._moveCursor(-1);
            },
            moveCursorDown: function() {
                this._moveCursor(+1);
            },
            getSuggestionUnderCursor: function() {
                var $suggestion = this._getSuggestions().filter(".tt-is-under-cursor").first();
                return $suggestion.length > 0 ? extractSuggestion($suggestion) : null;
            },
            getFirstSuggestion: function() {
                var $suggestion = this._getSuggestions().first();
                return $suggestion.length > 0 ? extractSuggestion($suggestion) : null;
            },
            renderSuggestions: function(dataset, suggestions) {
                var datasetClassName = "tt-dataset-" + dataset.name, wrapper = '<div class="tt-suggestion">%body</div>', compiledHtml, $suggestionsList, $dataset = this.$menu.find("." + datasetClassName), elBuilder, fragment, $el;
                if ($dataset.length === 0) {
                    $suggestionsList = $(html.suggestionsList).css(css.suggestionsList);
                    $dataset = $("<div></div>").addClass(datasetClassName).append(dataset.header).append($suggestionsList).append(dataset.footer).appendTo(this.$menu);
                }
                if (suggestions.length > 0) {
                    this.isEmpty = false;
                    this.isOpen && this._show();
                    if (utils.isFunction(dataset.render)) {
                        var element = $dataset.show().find(".tt-suggestions");
                        element.empty();
                        dataset.render(element, suggestions);
                    } else {
                        elBuilder = document.createElement("div");
                        fragment = document.createDocumentFragment();
                        utils.each(suggestions, function(i, suggestion) {
                            suggestion.dataset = dataset.name;
                            compiledHtml = dataset.template(suggestion.datum);
                            elBuilder.innerHTML = wrapper.replace("%body", compiledHtml);
                            $el = $(elBuilder.firstChild).css(css.suggestion).data("suggestion", suggestion);
                            $el.children().each(function() {
                                $(this).css(css.suggestionChild);
                            });
                            fragment.appendChild($el[0]);
                        });
                        $dataset.show().find(".tt-suggestions").html(fragment);
                    }
                } else {
                    this.clearSuggestions(dataset.name);
                }
                this.trigger("suggestionsRendered");
            },
            clearSuggestions: function(datasetName) {
                var $datasets = datasetName ? this.$menu.find(".tt-dataset-" + datasetName) : this.$menu.find('[class^="tt-dataset-"]'), $suggestions = $datasets.find(".tt-suggestions");
                $datasets.hide();
                $suggestions.empty();
                if (this._getSuggestions().length === 0) {
                    this.isEmpty = true;
                    this._hide();
                }
            }
        });
        return DropdownView;
        function extractSuggestion($el) {
            return $el.data("suggestion");
        }
    }();
    var TypeaheadView = function() {
        var html = {
            wrapper: '<span class="twitter-typeahead"></span>',
            hint: '<input class="tt-hint" type="text" autocomplete="off" spellcheck="off" disabled>',
            dropdown: '<span class="tt-dropdown-menu"></span>'
        }, css = {
            wrapper: {
                position: "relative",
                display: "inline-block"
            },
            hint: {
                position: "absolute",
                top: "0",
                left: "0",
                borderColor: "transparent",
                boxShadow: "none"
            },
            query: {
                position: "relative",
                verticalAlign: "top",
                backgroundColor: "transparent"
            },
            dropdown: {
                position: "absolute",
                top: "100%",
                left: "0",
                zIndex: "100",
                display: "none"
            }
        };
        if (utils.isMsie()) {
            utils.mixin(css.query, {
                backgroundImage: "url(data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)"
            });
        }
        if (utils.isMsie() && utils.isMsie() <= 7) {
            utils.mixin(css.wrapper, {
                display: "inline",
                zoom: "1"
            });
            utils.mixin(css.query, {
                marginTop: "-1px"
            });
        }
        function TypeaheadView(o) {
            var $menu, $input, $hint;
            utils.bindAll(this);
            this.$node = buildDomStructure(o.input);
            this.datasets = o.datasets;
            this.dir = null;
            this.eventBus = o.eventBus;
            $menu = this.$node.find(".tt-dropdown-menu");
            $input = this.$node.find(".tt-query");
            $hint = this.$node.find(".tt-hint");
            this.dropdownView = new DropdownView({
                menu: $menu
            }).on("suggestionSelected", this._handleSelection).on("cursorMoved", this._clearHint).on("cursorMoved", this._setInputValueToSuggestionUnderCursor).on("cursorRemoved", this._setInputValueToQuery).on("cursorRemoved", this._updateHint).on("suggestionsRendered", this._updateHint).on("opened", this._updateHint).on("closed", this._clearHint).on("opened closed", this._propagateEvent);
            this.inputView = new InputView({
                input: $input,
                hint: $hint
            }).on("focused", this._openDropdown).on("blured", this._closeDropdown).on("blured", this._setInputValueToQuery).on("enterKeyed tabKeyed", this._handleSelection).on("queryChanged", this._clearHint).on("queryChanged", this._clearSuggestions).on("queryChanged", this._getSuggestions).on("whitespaceChanged", this._updateHint).on("queryChanged whitespaceChanged", this._openDropdown).on("queryChanged whitespaceChanged", this._setLanguageDirection).on("escKeyed", this._closeDropdown).on("escKeyed", this._setInputValueToQuery).on("tabKeyed upKeyed downKeyed", this._managePreventDefault).on("upKeyed downKeyed", this._moveDropdownCursor).on("upKeyed downKeyed", this._openDropdown).on("tabKeyed leftKeyed rightKeyed", this._autocomplete);
        }
        utils.mixin(TypeaheadView.prototype, EventTarget, {
            _managePreventDefault: function(e) {
                var $e = e.data, hint, inputValue, preventDefault = false;
                switch (e.type) {
                  case "tabKeyed":
                    hint = this.inputView.getHintValue();
                    inputValue = this.inputView.getInputValue();
                    preventDefault = hint && hint !== inputValue;
                    break;

                  case "upKeyed":
                  case "downKeyed":
                    preventDefault = !$e.shiftKey && !$e.ctrlKey && !$e.metaKey;
                    break;
                }
                preventDefault && $e.preventDefault();
            },
            _setLanguageDirection: function() {
                var dir = this.inputView.getLanguageDirection();
                if (dir !== this.dir) {
                    this.dir = dir;
                    this.$node.css("direction", dir);
                    this.dropdownView.setLanguageDirection(dir);
                }
            },
            _updateHint: function() {
                var suggestion = this.dropdownView.getFirstSuggestion(), hint = suggestion ? suggestion.value : null, dropdownIsVisible = this.dropdownView.isVisible(), inputHasOverflow = this.inputView.isOverflow(), inputValue, query, escapedQuery, beginsWithQuery, match;
                if (hint && dropdownIsVisible && !inputHasOverflow) {
                    inputValue = this.inputView.getInputValue();
                    query = inputValue.replace(/\s{2,}/g, " ").replace(/^\s+/g, "");
                    escapedQuery = utils.escapeRegExChars(query);
                    beginsWithQuery = new RegExp("^(?:" + escapedQuery + ")(.*$)", "i");
                    match = beginsWithQuery.exec(hint);
                    this.inputView.setHintValue(inputValue + (match ? match[1] : ""));
                }
            },
            _clearHint: function() {
                this.inputView.setHintValue("");
            },
            _clearSuggestions: function() {
                this.dropdownView.clearSuggestions();
            },
            _setInputValueToQuery: function() {
                this.inputView.setInputValue(this.inputView.getQuery());
            },
            _setInputValueToSuggestionUnderCursor: function(e) {
                var suggestion = e.data;
                this.inputView.setInputValue(suggestion.value, true);
            },
            _openDropdown: function() {
                this.dropdownView.open();
            },
            _closeDropdown: function(e) {
                this.dropdownView[e.type === "blured" ? "closeUnlessMouseIsOverDropdown" : "close"]();
            },
            _moveDropdownCursor: function(e) {
                var $e = e.data;
                if (!$e.shiftKey && !$e.ctrlKey && !$e.metaKey) {
                    this.dropdownView[e.type === "upKeyed" ? "moveCursorUp" : "moveCursorDown"]();
                }
            },
            _handleSelection: function(e) {
                var byClick = e.type === "suggestionSelected", suggestion = byClick ? e.data : this.dropdownView.getSuggestionUnderCursor();
                if (suggestion) {
                    this.inputView.setInputValue(suggestion.value);
                    byClick ? this.inputView.focus() : e.data.preventDefault();
                    byClick && utils.isMsie() ? utils.defer(this.dropdownView.close) : this.dropdownView.close();
                    this.eventBus.trigger("selected", suggestion.datum, suggestion.dataset);
                }
            },
            _getSuggestions: function() {
                var that = this, query = this.inputView.getQuery();
                if (utils.isBlankString(query)) {
                    return;
                }
                utils.each(this.datasets, function(i, dataset) {
                    dataset.getSuggestions(query, function(suggestions) {
                        if (query === that.inputView.getQuery()) {
                            that.dropdownView.renderSuggestions(dataset, suggestions);
                        }
                    });
                });
            },
            _autocomplete: function(e) {
                var isCursorAtEnd, ignoreEvent, query, hint, suggestion;
                if (e.type === "rightKeyed" || e.type === "leftKeyed") {
                    isCursorAtEnd = this.inputView.isCursorAtEnd();
                    ignoreEvent = this.inputView.getLanguageDirection() === "ltr" ? e.type === "leftKeyed" : e.type === "rightKeyed";
                    if (!isCursorAtEnd || ignoreEvent) {
                        return;
                    }
                }
                query = this.inputView.getQuery();
                hint = this.inputView.getHintValue();
                if (hint !== "" && query !== hint) {
                    suggestion = this.dropdownView.getFirstSuggestion();
                    this.inputView.setInputValue(suggestion.value);
                    this.eventBus.trigger("autocompleted", suggestion.datum, suggestion.dataset);
                }
            },
            _propagateEvent: function(e) {
                this.eventBus.trigger(e.type);
            },
            destroy: function() {
                this.inputView.destroy();
                this.dropdownView.destroy();
                destroyDomStructure(this.$node);
                this.$node = null;
            },
            setQuery: function(query) {
                this.inputView.setQuery(query);
                this.inputView.setInputValue(query);
                this._clearHint();
                this._clearSuggestions();
                this._getSuggestions();
            }
        });
        return TypeaheadView;
        function buildDomStructure(input) {
            var $wrapper = $(html.wrapper), $dropdown = $(html.dropdown), $input = $(input), $hint = $(html.hint);
            $wrapper = $wrapper.css(css.wrapper);
            $dropdown = $dropdown.css(css.dropdown);
            $hint.css(css.hint).css({
                backgroundAttachment: $input.css("background-attachment"),
                backgroundClip: $input.css("background-clip"),
                backgroundColor: $input.css("background-color"),
                backgroundImage: $input.css("background-image"),
                backgroundOrigin: $input.css("background-origin"),
                backgroundPosition: $input.css("background-position"),
                backgroundRepeat: $input.css("background-repeat"),
                backgroundSize: $input.css("background-size")
            });
            $input.data("ttAttrs", {
                dir: $input.attr("dir"),
                autocomplete: $input.attr("autocomplete"),
                spellcheck: $input.attr("spellcheck"),
                style: $input.attr("style")
            });
            $input.addClass("tt-query").attr({
                autocomplete: "off",
                spellcheck: false
            }).css(css.query);
            try {
                !$input.attr("dir") && $input.attr("dir", "auto");
            } catch (e) {}
            return $input.wrap($wrapper).parent().prepend($hint).append($dropdown);
        }
        function destroyDomStructure($node) {
            var $input = $node.find(".tt-query");
            utils.each($input.data("ttAttrs"), function(key, val) {
                utils.isUndefined(val) ? $input.removeAttr(key) : $input.attr(key, val);
            });
            $input.detach().removeData("ttAttrs").removeClass("tt-query").insertAfter($node);
            $node.remove();
        }
    }();
    (function() {
        var cache = {}, viewKey = "ttView", methods;
        methods = {
            initialize: function(datasetDefs) {
                var datasets;
                datasetDefs = utils.isArray(datasetDefs) ? datasetDefs : [ datasetDefs ];
                if (datasetDefs.length === 0) {
                    $.error("no datasets provided");
                }
                datasets = utils.map(datasetDefs, function(o) {
                    var dataset = cache[o.name] ? cache[o.name] : new Dataset(o);
                    if (o.name) {
                        cache[o.name] = dataset;
                    }
                    return dataset;
                });
                return this.each(initialize);
                function initialize() {
                    var $input = $(this), deferreds, eventBus = new EventBus({
                        el: $input
                    });
                    deferreds = utils.map(datasets, function(dataset) {
                        return dataset.initialize();
                    });
                    $input.data(viewKey, new TypeaheadView({
                        input: $input,
                        eventBus: eventBus = new EventBus({
                            el: $input
                        }),
                        datasets: datasets
                    }));
                    $.when.apply($, deferreds).always(function() {
                        utils.defer(function() {
                            eventBus.trigger("initialized");
                        });
                    });
                }
            },
            destroy: function() {
                return this.each(destroy);
                function destroy() {
                    var $this = $(this), view = $this.data(viewKey);
                    if (view) {
                        view.destroy();
                        $this.removeData(viewKey);
                    }
                }
            },
            setQuery: function(query) {
                return this.each(setQuery);
                function setQuery() {
                    var view = $(this).data(viewKey);
                    view && view.setQuery(query);
                }
            }
        };
        jQuery.fn.typeahead = function(method) {
            if (methods[method]) {
                return methods[method].apply(this, [].slice.call(arguments, 1));
            } else {
                return methods.initialize.apply(this, arguments);
            }
        };
    })();
})(window.jQuery);