1 (function(){var t=this;var e=t.Backbone;var i=[];var r=i.push;var s=i.slice;var n=i.splice;var a;if(typeof exports!=="undefined"){a=exports}else{a=t.Backbone={}}a.VERSION="1.0.0";var h=t._;if(!h&&typeof require!=="undefined")h=require("underscore");a.$=t.jQuery||t.Zepto||t.ender||t.$;a.noConflict=function(){t.Backbone=e;return this};a.emulateHTTP=false;a.emulateJSON=false;var o=a.Events={on:function(t,e,i){if(!l(this,"on",t,[e,i])||!e)return this;this._events||(this._events={});var r=this._events[t]||(this._events[t]=[]);r.push({callback:e,context:i,ctx:i||this});return this},once:function(t,e,i){if(!l(this,"once",t,[e,i])||!e)return this;var r=this;var s=h.once(function(){r.off(t,s);e.apply(this,arguments)});s._callback=e;return this.on(t,s,i)},off:function(t,e,i){var r,s,n,a,o,u,c,f;if(!this._events||!l(this,"off",t,[e,i]))return this;if(!t&&!e&&!i){this._events={};return this}a=t?[t]:h.keys(this._events);for(o=0,u=a.length;o<u;o++){t=a[o];if(n=this._events[t]){this._events[t]=r=[];if(e||i){for(c=0,f=n.length;c<f;c++){s=n[c];if(e&&e!==s.callback&&e!==s.callback._callback||i&&i!==s.context){r.push(s)}}}if(!r.length)delete this._events[t]}}return this},trigger:function(t){if(!this._events)return this;var e=s.call(arguments,1);if(!l(this,"trigger",t,e))return this;var i=this._events[t];var r=this._events.all;if(i)c(i,e);if(r)c(r,arguments);return this},stopListening:function(t,e,i){var r=this._listeners;if(!r)return this;var s=!e&&!i;if(typeof e==="object")i=this;if(t)(r={})[t._listenerId]=t;for(var n in r){r[n].off(e,i,this);if(s)delete this._listeners[n]}return this}};var u=/\s+/;var l=function(t,e,i,r){if(!i)return true;if(typeof i==="object"){for(var s in i){t[e].apply(t,[s,i[s]].concat(r))}return false}if(u.test(i)){var n=i.split(u);for(var a=0,h=n.length;a<h;a++){t[e].apply(t,[n[a]].concat(r))}return false}return true};var c=function(t,e){var i,r=-1,s=t.length,n=e[0],a=e[1],h=e[2];switch(e.length){case 0:while(++r<s)(i=t[r]).callback.call(i.ctx);return;case 1:while(++r<s)(i=t[r]).callback.call(i.ctx,n);return;case 2:while(++r<s)(i=t[r]).callback.call(i.ctx,n,a);return;case 3:while(++r<s)(i=t[r]).callback.call(i.ctx,n,a,h);return;default:while(++r<s)(i=t[r]).callback.apply(i.ctx,e)}};var f={listenTo:"on",listenToOnce:"once"};h.each(f,function(t,e){o[e]=function(e,i,r){var s=this._listeners||(this._listeners={});var n=e._listenerId||(e._listenerId=h.uniqueId("l"));s[n]=e;if(typeof i==="object")r=this;e[t](i,r,this);return this}});o.bind=o.on;o.unbind=o.off;h.extend(a,o);var d=a.Model=function(t,e){var i;var r=t||{};e||(e={});this.cid=h.uniqueId("c");this.attributes={};h.extend(this,h.pick(e,p));if(e.parse)r=this.parse(r,e)||{};if(i=h.result(this,"defaults")){r=h.defaults({},r,i)}this.set(r,e);this.changed={};this.initialize.apply(this,arguments)};var p=["url","urlRoot","collection"];h.extend(d.prototype,o,{changed:null,validationError:null,idAttribute:"id",initialize:function(){},toJSON:function(t){return h.clone(this.attributes)},sync:function(){return a.sync.apply(this,arguments)},get:function(t){return this.attributes[t]},escape:function(t){return h.escape(this.get(t))},has:function(t){return this.get(t)!=null},set:function(t,e,i){var r,s,n,a,o,u,l,c;if(t==null)return this;if(typeof t==="object"){s=t;i=e}else{(s={})[t]=e}i||(i={});if(!this._validate(s,i))return false;n=i.unset;o=i.silent;a=[];u=this._changing;this._changing=true;if(!u){this._previousAttributes=h.clone(this.attributes);this.changed={}}c=this.attributes,l=this._previousAttributes;if(this.idAttribute in s)this.id=s[this.idAttribute];for(r in s){e=s[r];if(!h.isEqual(c[r],e))a.push(r);if(!h.isEqual(l[r],e)){this.changed[r]=e}else{delete this.changed[r]}n?delete c[r]:c[r]=e}if(!o){if(a.length)this._pending=true;for(var f=0,d=a.length;f<d;f++){this.trigger("change:"+a[f],this,c[a[f]],i)}}if(u)return this;if(!o){while(this._pending){this._pending=false;this.trigger("change",this,i)}}this._pending=false;this._changing=false;return this},unset:function(t,e){return this.set(t,void 0,h.extend({},e,{unset:true}))},clear:function(t){var e={};for(var i in this.attributes)e[i]=void 0;return this.set(e,h.extend({},t,{unset:true}))},hasChanged:function(t){if(t==null)return!h.isEmpty(this.changed);return h.has(this.changed,t)},changedAttributes:function(t){if(!t)return this.hasChanged()?h.clone(this.changed):false;var e,i=false;var r=this._changing?this._previousAttributes:this.attributes;for(var s in t){if(h.isEqual(r[s],e=t[s]))continue;(i||(i={}))[s]=e}return i},previous:function(t){if(t==null||!this._previousAttributes)return null;return this._previousAttributes[t]},previousAttributes:function(){return h.clone(this._previousAttributes)},fetch:function(t){t=t?h.clone(t):{};if(t.parse===void 0)t.parse=true;var e=this;var i=t.success;t.success=function(r){if(!e.set(e.parse(r,t),t))return false;if(i)i(e,r,t);e.trigger("sync",e,r,t)};R(this,t);return this.sync("read",this,t)},save:function(t,e,i){var r,s,n,a=this.attributes;if(t==null||typeof t==="object"){r=t;i=e}else{(r={})[t]=e}if(r&&(!i||!i.wait)&&!this.set(r,i))return false;i=h.extend({validate:true},i);if(!this._validate(r,i))return false;if(r&&i.wait){this.attributes=h.extend({},a,r)}if(i.parse===void 0)i.parse=true;var o=this;var u=i.success;i.success=function(t){o.attributes=a;var e=o.parse(t,i);if(i.wait)e=h.extend(r||{},e);if(h.isObject(e)&&!o.set(e,i)){return false}if(u)u(o,t,i);o.trigger("sync",o,t,i)};R(this,i);s=this.isNew()?"create":i.patch?"patch":"update";if(s==="patch")i.attrs=r;n=this.sync(s,this,i);if(r&&i.wait)this.attributes=a;return n},destroy:function(t){t=t?h.clone(t):{};var e=this;var i=t.success;var r=function(){e.trigger("destroy",e,e.collection,t)};t.success=function(s){if(t.wait||e.isNew())r();if(i)i(e,s,t);if(!e.isNew())e.trigger("sync",e,s,t)};if(this.isNew()){t.success();return false}R(this,t);var s=this.sync("delete",this,t);if(!t.wait)r();return s},url:function(){var t=h.result(this,"urlRoot")||h.result(this.collection,"url")||U();if(this.isNew())return t;return t+(t.charAt(t.length-1)==="/"?"":"/")+encodeURIComponent(this.id)},parse:function(t,e){return t},clone:function(){return new this.constructor(this.attributes)},isNew:function(){return this.id==null},isValid:function(t){return this._validate({},h.extend(t||{},{validate:true}))},_validate:function(t,e){if(!e.validate||!this.validate)return true;t=h.extend({},this.attributes,t);var i=this.validationError=this.validate(t,e)||null;if(!i)return true;this.trigger("invalid",this,i,h.extend(e||{},{validationError:i}));return false}});var v=["keys","values","pairs","invert","pick","omit"];h.each(v,function(t){d.prototype[t]=function(){var e=s.call(arguments);e.unshift(this.attributes);return h[t].apply(h,e)}});var g=a.Collection=function(t,e){e||(e={});if(e.url)this.url=e.url;if(e.model)this.model=e.model;if(e.comparator!==void 0)this.comparator=e.comparator;this._reset();this.initialize.apply(this,arguments);if(t)this.reset(t,h.extend({silent:true},e))};var m={add:true,remove:true,merge:true};var y={add:true,merge:false,remove:false};h.extend(g.prototype,o,{model:d,initialize:function(){},toJSON:function(t){return this.map(function(e){return e.toJSON(t)})},sync:function(){return a.sync.apply(this,arguments)},add:function(t,e){return this.set(t,h.defaults(e||{},y))},remove:function(t,e){t=h.isArray(t)?t.slice():[t];e||(e={});var i,r,s,n;for(i=0,r=t.length;i<r;i++){n=this.get(t[i]);if(!n)continue;delete this._byId[n.id];delete this._byId[n.cid];s=this.indexOf(n);this.models.splice(s,1);this.length--;if(!e.silent){e.index=s;n.trigger("remove",n,this,e)}this._removeReference(n)}return this},set:function(t,e){e=h.defaults(e||{},m);if(e.parse)t=this.parse(t,e);if(!h.isArray(t))t=t?[t]:[];var i,s,a,o,u,l;var c=e.at;var f=this.comparator&&c==null&&e.sort!==false;var d=h.isString(this.comparator)?this.comparator:null;var p=[],v=[],g={};for(i=0,s=t.length;i<s;i++){if(!(a=this._prepareModel(t[i],e)))continue;if(u=this.get(a)){if(e.remove)g[u.cid]=true;if(e.merge){u.set(a.attributes,e);if(f&&!l&&u.hasChanged(d))l=true}}else if(e.add){p.push(a);a.on("all",this._onModelEvent,this);this._byId[a.cid]=a;if(a.id!=null)this._byId[a.id]=a}}if(e.remove){for(i=0,s=this.length;i<s;++i){if(!g[(a=this.models[i]).cid])v.push(a)}if(v.length)this.remove(v,e)}if(p.length){if(f)l=true;this.length+=p.length;if(c!=null){n.apply(this.models,[c,0].concat(p))}else{r.apply(this.models,p)}}if(l)this.sort({silent:true});if(e.silent)return this;for(i=0,s=p.length;i<s;i++){(a=p[i]).trigger("add",a,this,e)}if(l)this.trigger("sort",this,e);return this},reset:function(t,e){e||(e={});for(var i=0,r=this.models.length;i<r;i++){this._removeReference(this.models[i])}e.previousModels=this.models;this._reset();this.add(t,h.extend({silent:true},e));if(!e.silent)this.trigger("reset",this,e);return this},push:function(t,e){t=this._prepareModel(t,e);this.add(t,h.extend({at:this.length},e));return t},pop:function(t){var e=this.at(this.length-1);this.remove(e,t);return e},unshift:function(t,e){t=this._prepareModel(t,e);this.add(t,h.extend({at:0},e));return t},shift:function(t){var e=this.at(0);this.remove(e,t);return e},slice:function(t,e){return this.models.slice(t,e)},get:function(t){if(t==null)return void 0;return this._byId[t.id!=null?t.id:t.cid||t]},at:function(t){return this.models[t]},where:function(t,e){if(h.isEmpty(t))return e?void 0:[];return this[e?"find":"filter"](function(e){for(var i in t){if(t[i]!==e.get(i))return false}return true})},findWhere:function(t){return this.where(t,true)},sort:function(t){if(!this.comparator)throw new Error("Cannot sort a set without a comparator");t||(t={});if(h.isString(this.comparator)||this.comparator.length===1){this.models=this.sortBy(this.comparator,this)}else{this.models.sort(h.bind(this.comparator,this))}if(!t.silent)this.trigger("sort",this,t);return this},sortedIndex:function(t,e,i){e||(e=this.comparator);var r=h.isFunction(e)?e:function(t){return t.get(e)};return h.sortedIndex(this.models,t,r,i)},pluck:function(t){return h.invoke(this.models,"get",t)},fetch:function(t){t=t?h.clone(t):{};if(t.parse===void 0)t.parse=true;var e=t.success;var i=this;t.success=function(r){var s=t.reset?"reset":"set";i[s](r,t);if(e)e(i,r,t);i.trigger("sync",i,r,t)};R(this,t);return this.sync("read",this,t)},create:function(t,e){e=e?h.clone(e):{};if(!(t=this._prepareModel(t,e)))return false;if(!e.wait)this.add(t,e);var i=this;var r=e.success;e.success=function(s){if(e.wait)i.add(t,e);if(r)r(t,s,e)};t.save(null,e);return t},parse:function(t,e){return t},clone:function(){return new this.constructor(this.models)},_reset:function(){this.length=0;this.models=[];this._byId={}},_prepareModel:function(t,e){if(t instanceof d){if(!t.collection)t.collection=this;return t}e||(e={});e.collection=this;var i=new this.model(t,e);if(!i._validate(t,e)){this.trigger("invalid",this,t,e);return false}return i},_removeReference:function(t){if(this===t.collection)delete t.collection;t.off("all",this._onModelEvent,this)},_onModelEvent:function(t,e,i,r){if((t==="add"||t==="remove")&&i!==this)return;if(t==="destroy")this.remove(e,r);if(e&&t==="change:"+e.idAttribute){delete this._byId[e.previous(e.idAttribute)];if(e.id!=null)this._byId[e.id]=e}this.trigger.apply(this,arguments)}});var _=["forEach","each","map","collect","reduce","foldl","inject","reduceRight","foldr","find","detect","filter","select","reject","every","all","some","any","include","contains","invoke","max","min","toArray","size","first","head","take","initial","rest","tail","drop","last","without","indexOf","shuffle","lastIndexOf","isEmpty","chain"];h.each(_,function(t){g.prototype[t]=function(){var e=s.call(arguments);e.unshift(this.models);return h[t].apply(h,e)}});var w=["groupBy","countBy","sortBy"];h.each(w,function(t){g.prototype[t]=function(e,i){var r=h.isFunction(e)?e:function(t){return t.get(e)};return h[t](this.models,r,i)}});var b=a.View=function(t){this.cid=h.uniqueId("view");this._configure(t||{});this._ensureElement();this.initialize.apply(this,arguments);this.delegateEvents()};var x=/^(\S+)\s*(.*)$/;var E=["model","collection","el","id","attributes","className","tagName","events"];h.extend(b.prototype,o,{tagName:"div",$:function(t){return this.$el.find(t)},initialize:function(){},render:function(){return this},remove:function(){this.$el.remove();this.stopListening();return this},setElement:function(t,e){if(this.$el)this.undelegateEvents();this.$el=t instanceof a.$?t:a.$(t);this.el=this.$el[0];if(e!==false)this.delegateEvents();return this},delegateEvents:function(t){if(!(t||(t=h.result(this,"events"))))return this;this.undelegateEvents();for(var e in t){var i=t[e];if(!h.isFunction(i))i=this[t[e]];if(!i)continue;var r=e.match(x);var s=r[1],n=r[2];i=h.bind(i,this);s+=".delegateEvents"+this.cid;if(n===""){this.$el.on(s,i)}else{this.$el.on(s,n,i)}}return this},undelegateEvents:function(){this.$el.off(".delegateEvents"+this.cid);return this},_configure:function(t){if(this.options)t=h.extend({},h.result(this,"options"),t);h.extend(this,h.pick(t,E));this.options=t},_ensureElement:function(){if(!this.el){var t=h.extend({},h.result(this,"attributes"));if(this.id)t.id=h.result(this,"id");if(this.className)t["class"]=h.result(this,"className");var e=a.$("<"+h.result(this,"tagName")+">").attr(t);this.setElement(e,false)}else{this.setElement(h.result(this,"el"),false)}}});a.sync=function(t,e,i){var r=k[t];h.defaults(i||(i={}),{emulateHTTP:a.emulateHTTP,emulateJSON:a.emulateJSON});var s={type:r,dataType:"json"};if(!i.url){s.url=h.result(e,"url")||U()}if(i.data==null&&e&&(t==="create"||t==="update"||t==="patch")){s.contentType="application/json";s.data=JSON.stringify(i.attrs||e.toJSON(i))}if(i.emulateJSON){s.contentType="application/x-www-form-urlencoded";s.data=s.data?{model:s.data}:{}}if(i.emulateHTTP&&(r==="PUT"||r==="DELETE"||r==="PATCH")){s.type="POST";if(i.emulateJSON)s.data._method=r;var n=i.beforeSend;i.beforeSend=function(t){t.setRequestHeader("X-HTTP-Method-Override",r);if(n)return n.apply(this,arguments)}}if(s.type!=="GET"&&!i.emulateJSON){s.processData=false}if(s.type==="PATCH"&&window.ActiveXObject&&!(window.external&&window.external.msActiveXFilteringEnabled)){s.xhr=function(){return new ActiveXObject("Microsoft.XMLHTTP")}}var o=i.xhr=a.ajax(h.extend(s,i));e.trigger("request",e,o,i);return o};var k={create:"POST",update:"PUT",patch:"PATCH","delete":"DELETE",read:"GET"};a.ajax=function(){return a.$.ajax.apply(a.$,arguments)};var S=a.Router=function(t){t||(t={});if(t.routes)this.routes=t.routes;this._bindRoutes();this.initialize.apply(this,arguments)};var $=/\((.*?)\)/g;var T=/(\(\?)?:\w+/g;var H=/\*\w+/g;var A=/[\-{}\[\]+?.,\\\^$|#\s]/g;h.extend(S.prototype,o,{initialize:function(){},route:function(t,e,i){if(!h.isRegExp(t))t=this._routeToRegExp(t);if(h.isFunction(e)){i=e;e=""}if(!i)i=this[e];var r=this;a.history.route(t,function(s){var n=r._extractParameters(t,s);i&&i.apply(r,n);r.trigger.apply(r,["route:"+e].concat(n));r.trigger("route",e,n);a.history.trigger("route",r,e,n)});return this},navigate:function(t,e){a.history.navigate(t,e);return this},_bindRoutes:function(){if(!this.routes)return;this.routes=h.result(this,"routes");var t,e=h.keys(this.routes);while((t=e.pop())!=null){this.route(t,this.routes[t])}},_routeToRegExp:function(t){t=t.replace(A,"\\$&").replace($,"(?:$1)?").replace(T,function(t,e){return e?t:"([^/]+)"}).replace(H,"(.*?)");return new RegExp("^"+t+"$")},_extractParameters:function(t,e){var i=t.exec(e).slice(1);return h.map(i,function(t){return t?decodeURIComponent(t):null})}});var I=a.History=function(){this.handlers=[];h.bindAll(this,"checkUrl");if(typeof window!=="undefined"){this.location=window.location;this.history=window.history}};var N=/^[#\/]|\s+$/g;var P=/^\/+|\/+$/g;var O=/msie [\w.]+/;var C=/\/$/;I.started=false;h.extend(I.prototype,o,{interval:50,getHash:function(t){var e=(t||this).location.href.match(/#(.*)$/);return e?e[1]:""},getFragment:function(t,e){if(t==null){if(this._hasPushState||!this._wantsHashChange||e){t=this.location.pathname;var i=this.root.replace(C,"");if(!t.indexOf(i))t=t.substr(i.length)}else{t=this.getHash()}}return t.replace(N,"")},start:function(t){if(I.started)throw new Error("Backbone.history has already been started");I.started=true;this.options=h.extend({},{root:"/"},this.options,t);this.root=this.options.root;this._wantsHashChange=this.options.hashChange!==false;this._wantsPushState=!!this.options.pushState;this._hasPushState=!!(this.options.pushState&&this.history&&this.history.pushState);var e=this.getFragment();var i=document.documentMode;var r=O.exec(navigator.userAgent.toLowerCase())&&(!i||i<=7);this.root=("/"+this.root+"/").replace(P,"/");if(r&&this._wantsHashChange){this.iframe=a.$('<iframe src="javascript:0" tabindex="-1" />').hide().appendTo("body")[0].contentWindow;this.navigate(e)}if(this._hasPushState){a.$(window).on("popstate",this.checkUrl)}else if(this._wantsHashChange&&"onhashchange"in window&&!r){a.$(window).on("hashchange",this.checkUrl)}else if(this._wantsHashChange){this._checkUrlInterval=setInterval(this.checkUrl,this.interval)}this.fragment=e;var s=this.location;var n=s.pathname.replace(/[^\/]$/,"$&/")===this.root;if(this._wantsHashChange&&this._wantsPushState&&!this._hasPushState&&!n){this.fragment=this.getFragment(null,true);this.location.replace(this.root+this.location.search+"#"+this.fragment);return true}else if(this._wantsPushState&&this._hasPushState&&n&&s.hash){this.fragment=this.getHash().replace(N,"");this.history.replaceState({},document.title,this.root+this.fragment+s.search)}if(!this.options.silent)return this.loadUrl()},stop:function(){a.$(window).off("popstate",this.checkUrl).off("hashchange",this.checkUrl);clearInterval(this._checkUrlInterval);I.started=false},route:function(t,e){this.handlers.unshift({route:t,callback:e})},checkUrl:function(t){var e=this.getFragment();if(e===this.fragment&&this.iframe){e=this.getFragment(this.getHash(this.iframe))}if(e===this.fragment)return false;if(this.iframe)this.navigate(e);this.loadUrl()||this.loadUrl(this.getHash())},loadUrl:function(t){var e=this.fragment=this.getFragment(t);var i=h.any(this.handlers,function(t){if(t.route.test(e)){t.callback(e);return true}});return i},navigate:function(t,e){if(!I.started)return false;if(!e||e===true)e={trigger:e};t=this.getFragment(t||"");if(this.fragment===t)return;this.fragment=t;var i=this.root+t;if(this._hasPushState){this.history[e.replace?"replaceState":"pushState"]({},document.title,i)}else if(this._wantsHashChange){this._updateHash(this.location,t,e.replace);if(this.iframe&&t!==this.getFragment(this.getHash(this.iframe))){if(!e.replace)this.iframe.document.open().close();this._updateHash(this.iframe.location,t,e.replace)}}else{return this.location.assign(i)}if(e.trigger)this.loadUrl(t)},_updateHash:function(t,e,i){if(i){var r=t.href.replace(/(javascript:|#).*$/,"");t.replace(r+"#"+e)}else{t.hash="#"+e}}});a.history=new I;var j=function(t,e){var i=this;var r;if(t&&h.has(t,"constructor")){r=t.constructor}else{r=function(){return i.apply(this,arguments)}}h.extend(r,i,e);var s=function(){this.constructor=r};s.prototype=i.prototype;r.prototype=new s;if(t)h.extend(r.prototype,t);r.__super__=i.prototype;return r};d.extend=g.extend=S.extend=b.extend=I.extend=j;var U=function(){throw new Error('A "url" property or function must be specified')};var R=function(t,e){var i=e.error;e.error=function(r){if(i)i(t,r,e);t.trigger("error",t,r,e)}}}).call(this);

     1 //     Backbone.js 1.2.3

     2 /*

     2 

     3 //@ sourceMappingURL=backbone-min.map

     3 //     (c) 2010-2015 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors

     4 */

     4 //     Backbone may be freely distributed under the MIT license.

     5 //     For all details and documentation:

     6 //     http://backbonejs.org

     7 

     8 (function(factory) {

     9 

    10   // Establish the root object, `window` (`self`) in the browser, or `global` on the server.

    11   // We use `self` instead of `window` for `WebWorker` support.

    12   var root = (typeof self == 'object' && self.self == self && self) ||

    13             (typeof global == 'object' && global.global == global && global);

    14 

    15   // Set up Backbone appropriately for the environment. Start with AMD.

    16   if (typeof define === 'function' && define.amd) {

    17     define(['underscore', 'jquery', 'exports'], function(_, $, exports) {

    18       // Export global even in AMD case in case this script is loaded with

    19       // others that may still expect a global Backbone.

    20       root.Backbone = factory(root, exports, _, $);

    21     });

    22 

    23   // Next for Node.js or CommonJS. jQuery may not be needed as a module.

    24   } else if (typeof exports !== 'undefined') {

    25     var _ = require('underscore'), $;

    26     try { $ = require('jquery'); } catch(e) {}

    27     factory(root, exports, _, $);

    28 

    29   // Finally, as a browser global.

    30   } else {

    31     root.Backbone = factory(root, {}, root._, (root.jQuery || root.Zepto || root.ender || root.$));

    32   }

    33 

    34 }(function(root, Backbone, _, $) {

    35 

    36   // Initial Setup

    37   // -------------

    38 

    39   // Save the previous value of the `Backbone` variable, so that it can be

    40   // restored later on, if `noConflict` is used.

    41   var previousBackbone = root.Backbone;

    42 

    43   // Create a local reference to a common array method we'll want to use later.

    44   var slice = Array.prototype.slice;

    45 

    46   // Current version of the library. Keep in sync with `package.json`.

    47   Backbone.VERSION = '1.2.3';

    48 

    49   // For Backbone's purposes, jQuery, Zepto, Ender, or My Library (kidding) owns

    50   // the `$` variable.

    51   Backbone.$ = $;

    52 

    53   // Runs Backbone.js in *noConflict* mode, returning the `Backbone` variable

    54   // to its previous owner. Returns a reference to this Backbone object.

    55   Backbone.noConflict = function() {

    56     root.Backbone = previousBackbone;

    57     return this;

    58   };

    59 

    60   // Turn on `emulateHTTP` to support legacy HTTP servers. Setting this option

    61   // will fake `"PATCH"`, `"PUT"` and `"DELETE"` requests via the `_method` parameter and

    62   // set a `X-Http-Method-Override` header.

    63   Backbone.emulateHTTP = false;

    64 

    65   // Turn on `emulateJSON` to support legacy servers that can't deal with direct

    66   // `application/json` requests ... this will encode the body as

    67   // `application/x-www-form-urlencoded` instead and will send the model in a

    68   // form param named `model`.

    69   Backbone.emulateJSON = false;

    70 

    71   // Proxy Backbone class methods to Underscore functions, wrapping the model's

    72   // `attributes` object or collection's `models` array behind the scenes.

    73   //

    74   // collection.filter(function(model) { return model.get('age') > 10 });

    75   // collection.each(this.addView);

    76   //

    77   // `Function#apply` can be slow so we use the method's arg count, if we know it.

    78   var addMethod = function(length, method, attribute) {

    79     switch (length) {

    80       case 1: return function() {

    81         return _[method](this[attribute]);

    82       };

    83       case 2: return function(value) {

    84         return _[method](this[attribute], value);

    85       };

    86       case 3: return function(iteratee, context) {

    87         return _[method](this[attribute], cb(iteratee, this), context);

    88       };

    89       case 4: return function(iteratee, defaultVal, context) {

    90         return _[method](this[attribute], cb(iteratee, this), defaultVal, context);

    91       };

    92       default: return function() {

    93         var args = slice.call(arguments);

    94         args.unshift(this[attribute]);

    95         return _[method].apply(_, args);

    96       };

    97     }

    98   };

    99   var addUnderscoreMethods = function(Class, methods, attribute) {

   100     _.each(methods, function(length, method) {

   101       if (_[method]) Class.prototype[method] = addMethod(length, method, attribute);

   102     });

   103   };

   104 

   105   // Support `collection.sortBy('attr')` and `collection.findWhere({id: 1})`.

   106   var cb = function(iteratee, instance) {

   107     if (_.isFunction(iteratee)) return iteratee;

   108     if (_.isObject(iteratee) && !instance._isModel(iteratee)) return modelMatcher(iteratee);

   109     if (_.isString(iteratee)) return function(model) { return model.get(iteratee); };

   110     return iteratee;

   111   };

   112   var modelMatcher = function(attrs) {

   113     var matcher = _.matches(attrs);

   114     return function(model) {

   115       return matcher(model.attributes);

   116     };

   117   };

   118 

   119   // Backbone.Events

   120   // ---------------

   121 

   122   // A module that can be mixed in to *any object* in order to provide it with

   123   // a custom event channel. You may bind a callback to an event with `on` or

   124   // remove with `off`; `trigger`-ing an event fires all callbacks in

   125   // succession.

   126   //

   127   //     var object = {};

   128   //     _.extend(object, Backbone.Events);

   129   //     object.on('expand', function(){ alert('expanded'); });

   130   //     object.trigger('expand');

   131   //

   132   var Events = Backbone.Events = {};

   133 

   134   // Regular expression used to split event strings.

   135   var eventSplitter = /\s+/;

   136 

   137   // Iterates over the standard `event, callback` (as well as the fancy multiple

   138   // space-separated events `"change blur", callback` and jQuery-style event

   139   // maps `{event: callback}`).

   140   var eventsApi = function(iteratee, events, name, callback, opts) {

   141     var i = 0, names;

   142     if (name && typeof name === 'object') {

   143       // Handle event maps.

   144       if (callback !== void 0 && 'context' in opts && opts.context === void 0) opts.context = callback;

   145       for (names = _.keys(name); i < names.length ; i++) {

   146         events = eventsApi(iteratee, events, names[i], name[names[i]], opts);

   147       }

   148     } else if (name && eventSplitter.test(name)) {

   149       // Handle space separated event names by delegating them individually.

   150       for (names = name.split(eventSplitter); i < names.length; i++) {

   151         events = iteratee(events, names[i], callback, opts);

   152       }

   153     } else {

   154       // Finally, standard events.

   155       events = iteratee(events, name, callback, opts);

   156     }

   157     return events;

   158   };

   159 

   160   // Bind an event to a `callback` function. Passing `"all"` will bind

   161   // the callback to all events fired.

   162   Events.on = function(name, callback, context) {

   163     return internalOn(this, name, callback, context);

   164   };

   165 

   166   // Guard the `listening` argument from the public API.

   167   var internalOn = function(obj, name, callback, context, listening) {

   168     obj._events = eventsApi(onApi, obj._events || {}, name, callback, {

   169         context: context,

   170         ctx: obj,

   171         listening: listening

   172     });

   173 

   174     if (listening) {

   175       var listeners = obj._listeners || (obj._listeners = {});

   176       listeners[listening.id] = listening;

   177     }

   178 

   179     return obj;

   180   };

   181 

   182   // Inversion-of-control versions of `on`. Tell *this* object to listen to

   183   // an event in another object... keeping track of what it's listening to

   184   // for easier unbinding later.

   185   Events.listenTo =  function(obj, name, callback) {

   186     if (!obj) return this;

   187     var id = obj._listenId || (obj._listenId = _.uniqueId('l'));

   188     var listeningTo = this._listeningTo || (this._listeningTo = {});

   189     var listening = listeningTo[id];

   190 

   191     // This object is not listening to any other events on `obj` yet.

   192     // Setup the necessary references to track the listening callbacks.

   193     if (!listening) {

   194       var thisId = this._listenId || (this._listenId = _.uniqueId('l'));

   195       listening = listeningTo[id] = {obj: obj, objId: id, id: thisId, listeningTo: listeningTo, count: 0};

   196     }

   197 

   198     // Bind callbacks on obj, and keep track of them on listening.

   199     internalOn(obj, name, callback, this, listening);

   200     return this;

   201   };

   202 

   203   // The reducing API that adds a callback to the `events` object.

   204   var onApi = function(events, name, callback, options) {

   205     if (callback) {

   206       var handlers = events[name] || (events[name] = []);

   207       var context = options.context, ctx = options.ctx, listening = options.listening;

   208       if (listening) listening.count++;

   209 

   210       handlers.push({ callback: callback, context: context, ctx: context || ctx, listening: listening });

   211     }

   212     return events;

   213   };

   214 

   215   // Remove one or many callbacks. If `context` is null, removes all

   216   // callbacks with that function. If `callback` is null, removes all

   217   // callbacks for the event. If `name` is null, removes all bound

   218   // callbacks for all events.

   219   Events.off =  function(name, callback, context) {

   220     if (!this._events) return this;

   221     this._events = eventsApi(offApi, this._events, name, callback, {

   222         context: context,

   223         listeners: this._listeners

   224     });

   225     return this;

   226   };

   227 

   228   // Tell this object to stop listening to either specific events ... or

   229   // to every object it's currently listening to.

   230   Events.stopListening =  function(obj, name, callback) {

   231     var listeningTo = this._listeningTo;

   232     if (!listeningTo) return this;

   233 

   234     var ids = obj ? [obj._listenId] : _.keys(listeningTo);

   235 

   236     for (var i = 0; i < ids.length; i++) {

   237       var listening = listeningTo[ids[i]];

   238 

   239       // If listening doesn't exist, this object is not currently

   240       // listening to obj. Break out early.

   241       if (!listening) break;

   242 

   243       listening.obj.off(name, callback, this);

   244     }

   245     if (_.isEmpty(listeningTo)) this._listeningTo = void 0;

   246 

   247     return this;

   248   };

   249 

   250   // The reducing API that removes a callback from the `events` object.

   251   var offApi = function(events, name, callback, options) {

   252     if (!events) return;

   253 

   254     var i = 0, listening;

   255     var context = options.context, listeners = options.listeners;

   256 

   257     // Delete all events listeners and "drop" events.

   258     if (!name && !callback && !context) {

   259       var ids = _.keys(listeners);

   260       for (; i < ids.length; i++) {

   261         listening = listeners[ids[i]];

   262         delete listeners[listening.id];

   263         delete listening.listeningTo[listening.objId];

   264       }

   265       return;

   266     }

   267 

   268     var names = name ? [name] : _.keys(events);

   269     for (; i < names.length; i++) {

   270       name = names[i];

   271       var handlers = events[name];

   272 

   273       // Bail out if there are no events stored.

   274       if (!handlers) break;

   275 

   276       // Replace events if there are any remaining.  Otherwise, clean up.

   277       var remaining = [];

   278       for (var j = 0; j < handlers.length; j++) {

   279         var handler = handlers[j];

   280         if (

   281           callback && callback !== handler.callback &&

   282             callback !== handler.callback._callback ||

   283               context && context !== handler.context

   284         ) {

   285           remaining.push(handler);

   286         } else {

   287           listening = handler.listening;

   288           if (listening && --listening.count === 0) {

   289             delete listeners[listening.id];

   290             delete listening.listeningTo[listening.objId];

   291           }

   292         }

   293       }

   294 

   295       // Update tail event if the list has any events.  Otherwise, clean up.

   296       if (remaining.length) {

   297         events[name] = remaining;

   298       } else {

   299         delete events[name];

   300       }

   301     }

   302     if (_.size(events)) return events;

   303   };

   304 

   305   // Bind an event to only be triggered a single time. After the first time

   306   // the callback is invoked, its listener will be removed. If multiple events

   307   // are passed in using the space-separated syntax, the handler will fire

   308   // once for each event, not once for a combination of all events.

   309   Events.once =  function(name, callback, context) {

   310     // Map the event into a `{event: once}` object.

   311     var events = eventsApi(onceMap, {}, name, callback, _.bind(this.off, this));

   312     return this.on(events, void 0, context);

   313   };

   314 

   315   // Inversion-of-control versions of `once`.

   316   Events.listenToOnce =  function(obj, name, callback) {

   317     // Map the event into a `{event: once}` object.

   318     var events = eventsApi(onceMap, {}, name, callback, _.bind(this.stopListening, this, obj));

   319     return this.listenTo(obj, events);

   320   };

   321 

   322   // Reduces the event callbacks into a map of `{event: onceWrapper}`.

   323   // `offer` unbinds the `onceWrapper` after it has been called.

   324   var onceMap = function(map, name, callback, offer) {

   325     if (callback) {

   326       var once = map[name] = _.once(function() {

   327         offer(name, once);

   328         callback.apply(this, arguments);

   329       });

   330       once._callback = callback;

   331     }

   332     return map;

   333   };

   334 

   335   // Trigger one or many events, firing all bound callbacks. Callbacks are

   336   // passed the same arguments as `trigger` is, apart from the event name

   337   // (unless you're listening on `"all"`, which will cause your callback to

   338   // receive the true name of the event as the first argument).

   339   Events.trigger =  function(name) {

   340     if (!this._events) return this;

   341 

   342     var length = Math.max(0, arguments.length - 1);

   343     var args = Array(length);

   344     for (var i = 0; i < length; i++) args[i] = arguments[i + 1];

   345 

   346     eventsApi(triggerApi, this._events, name, void 0, args);

   347     return this;

   348   };

   349 

   350   // Handles triggering the appropriate event callbacks.

   351   var triggerApi = function(objEvents, name, cb, args) {

   352     if (objEvents) {

   353       var events = objEvents[name];

   354       var allEvents = objEvents.all;

   355       if (events && allEvents) allEvents = allEvents.slice();

   356       if (events) triggerEvents(events, args);

   357       if (allEvents) triggerEvents(allEvents, [name].concat(args));

   358     }

   359     return objEvents;

   360   };

   361 

   362   // A difficult-to-believe, but optimized internal dispatch function for

   363   // triggering events. Tries to keep the usual cases speedy (most internal

   364   // Backbone events have 3 arguments).

   365   var triggerEvents = function(events, args) {

   366     var ev, i = -1, l = events.length, a1 = args[0], a2 = args[1], a3 = args[2];

   367     switch (args.length) {

   368       case 0: while (++i < l) (ev = events[i]).callback.call(ev.ctx); return;

   369       case 1: while (++i < l) (ev = events[i]).callback.call(ev.ctx, a1); return;

   370       case 2: while (++i < l) (ev = events[i]).callback.call(ev.ctx, a1, a2); return;

   371       case 3: while (++i < l) (ev = events[i]).callback.call(ev.ctx, a1, a2, a3); return;

   372       default: while (++i < l) (ev = events[i]).callback.apply(ev.ctx, args); return;

   373     }

   374   };

   375 

   376   // Aliases for backwards compatibility.

   377   Events.bind   = Events.on;

   378   Events.unbind = Events.off;

   379 

   380   // Allow the `Backbone` object to serve as a global event bus, for folks who

   381   // want global "pubsub" in a convenient place.

   382   _.extend(Backbone, Events);

   383 

   384   // Backbone.Model

   385   // --------------

   386 

   387   // Backbone **Models** are the basic data object in the framework --

   388   // frequently representing a row in a table in a database on your server.

   389   // A discrete chunk of data and a bunch of useful, related methods for

   390   // performing computations and transformations on that data.

   391 

   392   // Create a new model with the specified attributes. A client id (`cid`)

   393   // is automatically generated and assigned for you.

   394   var Model = Backbone.Model = function(attributes, options) {

   395     var attrs = attributes || {};

   396     options || (options = {});

   397     this.cid = _.uniqueId(this.cidPrefix);

   398     this.attributes = {};

   399     if (options.collection) this.collection = options.collection;

   400     if (options.parse) attrs = this.parse(attrs, options) || {};

   401     attrs = _.defaults({}, attrs, _.result(this, 'defaults'));

   402     this.set(attrs, options);

   403     this.changed = {};

   404     this.initialize.apply(this, arguments);

   405   };

   406 

   407   // Attach all inheritable methods to the Model prototype.

   408   _.extend(Model.prototype, Events, {

   409 

   410     // A hash of attributes whose current and previous value differ.

   411     changed: null,

   412 

   413     // The value returned during the last failed validation.

   414     validationError: null,

   415 

   416     // The default name for the JSON `id` attribute is `"id"`. MongoDB and

   417     // CouchDB users may want to set this to `"_id"`.

   418     idAttribute: 'id',

   419 

   420     // The prefix is used to create the client id which is used to identify models locally.

   421     // You may want to override this if you're experiencing name clashes with model ids.

   422     cidPrefix: 'c',

   423 

   424     // Initialize is an empty function by default. Override it with your own

   425     // initialization logic.

   426     initialize: function(){},

   427 

   428     // Return a copy of the model's `attributes` object.

   429     toJSON: function(options) {

   430       return _.clone(this.attributes);

   431     },

   432 

   433     // Proxy `Backbone.sync` by default -- but override this if you need

   434     // custom syncing semantics for *this* particular model.

   435     sync: function() {

   436       return Backbone.sync.apply(this, arguments);

   437     },

   438 

   439     // Get the value of an attribute.

   440     get: function(attr) {

   441       return this.attributes[attr];

   442     },

   443 

   444     // Get the HTML-escaped value of an attribute.

   445     escape: function(attr) {

   446       return _.escape(this.get(attr));

   447     },

   448 

   449     // Returns `true` if the attribute contains a value that is not null

   450     // or undefined.

   451     has: function(attr) {

   452       return this.get(attr) != null;

   453     },

   454 

   455     // Special-cased proxy to underscore's `_.matches` method.

   456     matches: function(attrs) {

   457       return !!_.iteratee(attrs, this)(this.attributes);

   458     },

   459 

   460     // Set a hash of model attributes on the object, firing `"change"`. This is

   461     // the core primitive operation of a model, updating the data and notifying

   462     // anyone who needs to know about the change in state. The heart of the beast.

   463     set: function(key, val, options) {

   464       if (key == null) return this;

   465 

   466       // Handle both `"key", value` and `{key: value}` -style arguments.

   467       var attrs;

   468       if (typeof key === 'object') {

   469         attrs = key;

   470         options = val;

   471       } else {

   472         (attrs = {})[key] = val;

   473       }

   474 

   475       options || (options = {});

   476 

   477       // Run validation.

   478       if (!this._validate(attrs, options)) return false;

   479 

   480       // Extract attributes and options.

   481       var unset      = options.unset;

   482       var silent     = options.silent;

   483       var changes    = [];

   484       var changing   = this._changing;

   485       this._changing = true;

   486 

   487       if (!changing) {

   488         this._previousAttributes = _.clone(this.attributes);

   489         this.changed = {};

   490       }

   491 

   492       var current = this.attributes;

   493       var changed = this.changed;

   494       var prev    = this._previousAttributes;

   495 

   496       // For each `set` attribute, update or delete the current value.

   497       for (var attr in attrs) {

   498         val = attrs[attr];

   499         if (!_.isEqual(current[attr], val)) changes.push(attr);

   500         if (!_.isEqual(prev[attr], val)) {

   501           changed[attr] = val;

   502         } else {

   503           delete changed[attr];

   504         }

   505         unset ? delete current[attr] : current[attr] = val;

   506       }

   507 

   508       // Update the `id`.

   509       this.id = this.get(this.idAttribute);

   510 

   511       // Trigger all relevant attribute changes.

   512       if (!silent) {

   513         if (changes.length) this._pending = options;

   514         for (var i = 0; i < changes.length; i++) {

   515           this.trigger('change:' + changes[i], this, current[changes[i]], options);

   516         }

   517       }

   518 

   519       // You might be wondering why there's a `while` loop here. Changes can

   520       // be recursively nested within `"change"` events.

   521       if (changing) return this;

   522       if (!silent) {

   523         while (this._pending) {

   524           options = this._pending;

   525           this._pending = false;

   526           this.trigger('change', this, options);

   527         }

   528       }

   529       this._pending = false;

   530       this._changing = false;

   531       return this;

   532     },

   533 

   534     // Remove an attribute from the model, firing `"change"`. `unset` is a noop

   535     // if the attribute doesn't exist.

   536     unset: function(attr, options) {

   537       return this.set(attr, void 0, _.extend({}, options, {unset: true}));

   538     },

   539 

   540     // Clear all attributes on the model, firing `"change"`.

   541     clear: function(options) {

   542       var attrs = {};

   543       for (var key in this.attributes) attrs[key] = void 0;

   544       return this.set(attrs, _.extend({}, options, {unset: true}));

   545     },

   546 

   547     // Determine if the model has changed since the last `"change"` event.

   548     // If you specify an attribute name, determine if that attribute has changed.

   549     hasChanged: function(attr) {

   550       if (attr == null) return !_.isEmpty(this.changed);

   551       return _.has(this.changed, attr);

   552     },

   553 

   554     // Return an object containing all the attributes that have changed, or

   555     // false if there are no changed attributes. Useful for determining what

   556     // parts of a view need to be updated and/or what attributes need to be

   557     // persisted to the server. Unset attributes will be set to undefined.

   558     // You can also pass an attributes object to diff against the model,

   559     // determining if there *would be* a change.

   560     changedAttributes: function(diff) {

   561       if (!diff) return this.hasChanged() ? _.clone(this.changed) : false;

   562       var old = this._changing ? this._previousAttributes : this.attributes;

   563       var changed = {};

   564       for (var attr in diff) {

   565         var val = diff[attr];

   566         if (_.isEqual(old[attr], val)) continue;

   567         changed[attr] = val;

   568       }

   569       return _.size(changed) ? changed : false;

   570     },

   571 

   572     // Get the previous value of an attribute, recorded at the time the last

   573     // `"change"` event was fired.

   574     previous: function(attr) {

   575       if (attr == null || !this._previousAttributes) return null;

   576       return this._previousAttributes[attr];

   577     },

   578 

   579     // Get all of the attributes of the model at the time of the previous

   580     // `"change"` event.

   581     previousAttributes: function() {

   582       return _.clone(this._previousAttributes);

   583     },

   584 

   585     // Fetch the model from the server, merging the response with the model's

   586     // local attributes. Any changed attributes will trigger a "change" event.

   587     fetch: function(options) {

   588       options = _.extend({parse: true}, options);

   589       var model = this;

   590       var success = options.success;

   591       options.success = function(resp) {

   592         var serverAttrs = options.parse ? model.parse(resp, options) : resp;

   593         if (!model.set(serverAttrs, options)) return false;

   594         if (success) success.call(options.context, model, resp, options);

   595         model.trigger('sync', model, resp, options);

   596       };

   597       wrapError(this, options);

   598       return this.sync('read', this, options);

   599     },

   600 

   601     // Set a hash of model attributes, and sync the model to the server.

   602     // If the server returns an attributes hash that differs, the model's

   603     // state will be `set` again.

   604     save: function(key, val, options) {

   605       // Handle both `"key", value` and `{key: value}` -style arguments.

   606       var attrs;

   607       if (key == null || typeof key === 'object') {

   608         attrs = key;

   609         options = val;

   610       } else {

   611         (attrs = {})[key] = val;

   612       }

   613 

   614       options = _.extend({validate: true, parse: true}, options);

   615       var wait = options.wait;

   616 

   617       // If we're not waiting and attributes exist, save acts as

   618       // `set(attr).save(null, opts)` with validation. Otherwise, check if

   619       // the model will be valid when the attributes, if any, are set.

   620       if (attrs && !wait) {

   621         if (!this.set(attrs, options)) return false;

   622       } else {

   623         if (!this._validate(attrs, options)) return false;

   624       }

   625 

   626       // After a successful server-side save, the client is (optionally)

   627       // updated with the server-side state.

   628       var model = this;

   629       var success = options.success;

   630       var attributes = this.attributes;

   631       options.success = function(resp) {

   632         // Ensure attributes are restored during synchronous saves.

   633         model.attributes = attributes;

   634         var serverAttrs = options.parse ? model.parse(resp, options) : resp;

   635         if (wait) serverAttrs = _.extend({}, attrs, serverAttrs);

   636         if (serverAttrs && !model.set(serverAttrs, options)) return false;

   637         if (success) success.call(options.context, model, resp, options);

   638         model.trigger('sync', model, resp, options);

   639       };

   640       wrapError(this, options);

   641 

   642       // Set temporary attributes if `{wait: true}` to properly find new ids.

   643       if (attrs && wait) this.attributes = _.extend({}, attributes, attrs);

   644 

   645       var method = this.isNew() ? 'create' : (options.patch ? 'patch' : 'update');

   646       if (method === 'patch' && !options.attrs) options.attrs = attrs;

   647       var xhr = this.sync(method, this, options);

   648 

   649       // Restore attributes.

   650       this.attributes = attributes;

   651 

   652       return xhr;

   653     },

   654 

   655     // Destroy this model on the server if it was already persisted.

   656     // Optimistically removes the model from its collection, if it has one.

   657     // If `wait: true` is passed, waits for the server to respond before removal.

   658     destroy: function(options) {

   659       options = options ? _.clone(options) : {};

   660       var model = this;

   661       var success = options.success;

   662       var wait = options.wait;

   663 

   664       var destroy = function() {

   665         model.stopListening();

   666         model.trigger('destroy', model, model.collection, options);

   667       };

   668 

   669       options.success = function(resp) {

   670         if (wait) destroy();

   671         if (success) success.call(options.context, model, resp, options);

   672         if (!model.isNew()) model.trigger('sync', model, resp, options);

   673       };

   674 

   675       var xhr = false;

   676       if (this.isNew()) {

   677         _.defer(options.success);

   678       } else {

   679         wrapError(this, options);

   680         xhr = this.sync('delete', this, options);

   681       }

   682       if (!wait) destroy();

   683       return xhr;

   684     },

   685 

   686     // Default URL for the model's representation on the server -- if you're

   687     // using Backbone's restful methods, override this to change the endpoint

   688     // that will be called.

   689     url: function() {

   690       var base =

   691         _.result(this, 'urlRoot') ||

   692         _.result(this.collection, 'url') ||

   693         urlError();

   694       if (this.isNew()) return base;

   695       var id = this.get(this.idAttribute);

   696       return base.replace(/[^\/]$/, '$&/') + encodeURIComponent(id);

   697     },

   698 

   699     // **parse** converts a response into the hash of attributes to be `set` on

   700     // the model. The default implementation is just to pass the response along.

   701     parse: function(resp, options) {

   702       return resp;

   703     },

   704 

   705     // Create a new model with identical attributes to this one.

   706     clone: function() {

   707       return new this.constructor(this.attributes);

   708     },

   709 

   710     // A model is new if it has never been saved to the server, and lacks an id.

   711     isNew: function() {

   712       return !this.has(this.idAttribute);

   713     },

   714 

   715     // Check if the model is currently in a valid state.

   716     isValid: function(options) {

   717       return this._validate({}, _.defaults({validate: true}, options));

   718     },

   719 

   720     // Run validation against the next complete set of model attributes,

   721     // returning `true` if all is well. Otherwise, fire an `"invalid"` event.

   722     _validate: function(attrs, options) {

   723       if (!options.validate || !this.validate) return true;

   724       attrs = _.extend({}, this.attributes, attrs);

   725       var error = this.validationError = this.validate(attrs, options) || null;

   726       if (!error) return true;

   727       this.trigger('invalid', this, error, _.extend(options, {validationError: error}));

   728       return false;

   729     }

   730 

   731   });

   732 

   733   // Underscore methods that we want to implement on the Model, mapped to the

   734   // number of arguments they take.

   735   var modelMethods = { keys: 1, values: 1, pairs: 1, invert: 1, pick: 0,

   736       omit: 0, chain: 1, isEmpty: 1 };

   737 

   738   // Mix in each Underscore method as a proxy to `Model#attributes`.

   739   addUnderscoreMethods(Model, modelMethods, 'attributes');

   740 

   741   // Backbone.Collection

   742   // -------------------

   743 

   744   // If models tend to represent a single row of data, a Backbone Collection is

   745   // more analogous to a table full of data ... or a small slice or page of that

   746   // table, or a collection of rows that belong together for a particular reason

   747   // -- all of the messages in this particular folder, all of the documents

   748   // belonging to this particular author, and so on. Collections maintain

   749   // indexes of their models, both in order, and for lookup by `id`.

   750 

   751   // Create a new **Collection**, perhaps to contain a specific type of `model`.

   752   // If a `comparator` is specified, the Collection will maintain

   753   // its models in sort order, as they're added and removed.

   754   var Collection = Backbone.Collection = function(models, options) {

   755     options || (options = {});

   756     if (options.model) this.model = options.model;

   757     if (options.comparator !== void 0) this.comparator = options.comparator;

   758     this._reset();

   759     this.initialize.apply(this, arguments);

   760     if (models) this.reset(models, _.extend({silent: true}, options));

   761   };

   762 

   763   // Default options for `Collection#set`.

   764   var setOptions = {add: true, remove: true, merge: true};

   765   var addOptions = {add: true, remove: false};

   766 

   767   // Splices `insert` into `array` at index `at`.

   768   var splice = function(array, insert, at) {

   769     at = Math.min(Math.max(at, 0), array.length);

   770     var tail = Array(array.length - at);

   771     var length = insert.length;

   772     for (var i = 0; i < tail.length; i++) tail[i] = array[i + at];

   773     for (i = 0; i < length; i++) array[i + at] = insert[i];

   774     for (i = 0; i < tail.length; i++) array[i + length + at] = tail[i];

   775   };

   776 

   777   // Define the Collection's inheritable methods.

   778   _.extend(Collection.prototype, Events, {

   779 

   780     // The default model for a collection is just a **Backbone.Model**.

   781     // This should be overridden in most cases.

   782     model: Model,

   783 

   784     // Initialize is an empty function by default. Override it with your own

   785     // initialization logic.

   786     initialize: function(){},

   787 

   788     // The JSON representation of a Collection is an array of the

   789     // models' attributes.

   790     toJSON: function(options) {

   791       return this.map(function(model) { return model.toJSON(options); });

   792     },

   793 

   794     // Proxy `Backbone.sync` by default.

   795     sync: function() {

   796       return Backbone.sync.apply(this, arguments);

   797     },

   798 

   799     // Add a model, or list of models to the set. `models` may be Backbone

   800     // Models or raw JavaScript objects to be converted to Models, or any

   801     // combination of the two.

   802     add: function(models, options) {

   803       return this.set(models, _.extend({merge: false}, options, addOptions));

   804     },

   805 

   806     // Remove a model, or a list of models from the set.

   807     remove: function(models, options) {

   808       options = _.extend({}, options);

   809       var singular = !_.isArray(models);

   810       models = singular ? [models] : _.clone(models);

   811       var removed = this._removeModels(models, options);

   812       if (!options.silent && removed) this.trigger('update', this, options);

   813       return singular ? removed[0] : removed;

   814     },

   815 

   816     // Update a collection by `set`-ing a new list of models, adding new ones,

   817     // removing models that are no longer present, and merging models that

   818     // already exist in the collection, as necessary. Similar to **Model#set**,

   819     // the core operation for updating the data contained by the collection.

   820     set: function(models, options) {

   821       if (models == null) return;

   822 

   823       options = _.defaults({}, options, setOptions);

   824       if (options.parse && !this._isModel(models)) models = this.parse(models, options);

   825 

   826       var singular = !_.isArray(models);

   827       models = singular ? [models] : models.slice();

   828 

   829       var at = options.at;

   830       if (at != null) at = +at;

   831       if (at < 0) at += this.length + 1;

   832 

   833       var set = [];

   834       var toAdd = [];

   835       var toRemove = [];

   836       var modelMap = {};

   837 

   838       var add = options.add;

   839       var merge = options.merge;

   840       var remove = options.remove;

   841 

   842       var sort = false;

   843       var sortable = this.comparator && (at == null) && options.sort !== false;

   844       var sortAttr = _.isString(this.comparator) ? this.comparator : null;

   845 

   846       // Turn bare objects into model references, and prevent invalid models

   847       // from being added.

   848       var model;

   849       for (var i = 0; i < models.length; i++) {

   850         model = models[i];

   851 

   852         // If a duplicate is found, prevent it from being added and

   853         // optionally merge it into the existing model.

   854         var existing = this.get(model);

   855         if (existing) {

   856           if (merge && model !== existing) {

   857             var attrs = this._isModel(model) ? model.attributes : model;

   858             if (options.parse) attrs = existing.parse(attrs, options);

   859             existing.set(attrs, options);

   860             if (sortable && !sort) sort = existing.hasChanged(sortAttr);

   861           }

   862           if (!modelMap[existing.cid]) {

   863             modelMap[existing.cid] = true;

   864             set.push(existing);

   865           }

   866           models[i] = existing;

   867 

   868         // If this is a new, valid model, push it to the `toAdd` list.

   869         } else if (add) {

   870           model = models[i] = this._prepareModel(model, options);

   871           if (model) {

   872             toAdd.push(model);

   873             this._addReference(model, options);

   874             modelMap[model.cid] = true;

   875             set.push(model);

   876           }

   877         }

   878       }

   879 

   880       // Remove stale models.

   881       if (remove) {

   882         for (i = 0; i < this.length; i++) {

   883           model = this.models[i];

   884           if (!modelMap[model.cid]) toRemove.push(model);

   885         }

   886         if (toRemove.length) this._removeModels(toRemove, options);

   887       }

   888 

   889       // See if sorting is needed, update `length` and splice in new models.

   890       var orderChanged = false;

   891       var replace = !sortable && add && remove;

   892       if (set.length && replace) {

   893         orderChanged = this.length != set.length || _.some(this.models, function(model, index) {

   894           return model !== set[index];

   895         });

   896         this.models.length = 0;

   897         splice(this.models, set, 0);

   898         this.length = this.models.length;

   899       } else if (toAdd.length) {

   900         if (sortable) sort = true;

   901         splice(this.models, toAdd, at == null ? this.length : at);

   902         this.length = this.models.length;

   903       }

   904 

   905       // Silently sort the collection if appropriate.

   906       if (sort) this.sort({silent: true});

   907 

   908       // Unless silenced, it's time to fire all appropriate add/sort events.

   909       if (!options.silent) {

   910         for (i = 0; i < toAdd.length; i++) {

   911           if (at != null) options.index = at + i;

   912           model = toAdd[i];

   913           model.trigger('add', model, this, options);

   914         }

   915         if (sort || orderChanged) this.trigger('sort', this, options);

   916         if (toAdd.length || toRemove.length) this.trigger('update', this, options);

   917       }

   918 

   919       // Return the added (or merged) model (or models).

   920       return singular ? models[0] : models;

   921     },

   922 

   923     // When you have more items than you want to add or remove individually,

   924     // you can reset the entire set with a new list of models, without firing

   925     // any granular `add` or `remove` events. Fires `reset` when finished.

   926     // Useful for bulk operations and optimizations.

   927     reset: function(models, options) {

   928       options = options ? _.clone(options) : {};

   929       for (var i = 0; i < this.models.length; i++) {

   930         this._removeReference(this.models[i], options);

   931       }

   932       options.previousModels = this.models;

   933       this._reset();

   934       models = this.add(models, _.extend({silent: true}, options));

   935       if (!options.silent) this.trigger('reset', this, options);

   936       return models;

   937     },

   938 

   939     // Add a model to the end of the collection.

   940     push: function(model, options) {

   941       return this.add(model, _.extend({at: this.length}, options));

   942     },

   943 

   944     // Remove a model from the end of the collection.

   945     pop: function(options) {

   946       var model = this.at(this.length - 1);

   947       return this.remove(model, options);

   948     },

   949 

   950     // Add a model to the beginning of the collection.

   951     unshift: function(model, options) {

   952       return this.add(model, _.extend({at: 0}, options));

   953     },

   954 

   955     // Remove a model from the beginning of the collection.

   956     shift: function(options) {

   957       var model = this.at(0);

   958       return this.remove(model, options);

   959     },

   960 

   961     // Slice out a sub-array of models from the collection.

   962     slice: function() {

   963       return slice.apply(this.models, arguments);

   964     },

   965 

   966     // Get a model from the set by id.

   967     get: function(obj) {

   968       if (obj == null) return void 0;

   969       var id = this.modelId(this._isModel(obj) ? obj.attributes : obj);

   970       return this._byId[obj] || this._byId[id] || this._byId[obj.cid];

   971     },

   972 

   973     // Get the model at the given index.

   974     at: function(index) {

   975       if (index < 0) index += this.length;

   976       return this.models[index];

   977     },

   978 

   979     // Return models with matching attributes. Useful for simple cases of

   980     // `filter`.

   981     where: function(attrs, first) {

   982       return this[first ? 'find' : 'filter'](attrs);

   983     },

   984 

   985     // Return the first model with matching attributes. Useful for simple cases

   986     // of `find`.

   987     findWhere: function(attrs) {

   988       return this.where(attrs, true);

   989     },

   990 

   991     // Force the collection to re-sort itself. You don't need to call this under

   992     // normal circumstances, as the set will maintain sort order as each item

   993     // is added.

   994     sort: function(options) {

   995       var comparator = this.comparator;

   996       if (!comparator) throw new Error('Cannot sort a set without a comparator');

   997       options || (options = {});

   998 

   999       var length = comparator.length;

  1000       if (_.isFunction(comparator)) comparator = _.bind(comparator, this);

  1001 

  1002       // Run sort based on type of `comparator`.

  1003       if (length === 1 || _.isString(comparator)) {

  1004         this.models = this.sortBy(comparator);

  1005       } else {

  1006         this.models.sort(comparator);

  1007       }

  1008       if (!options.silent) this.trigger('sort', this, options);

  1009       return this;

  1010     },

  1011 

  1012     // Pluck an attribute from each model in the collection.

  1013     pluck: function(attr) {

  1014       return _.invoke(this.models, 'get', attr);

  1015     },

  1016 

  1017     // Fetch the default set of models for this collection, resetting the

  1018     // collection when they arrive. If `reset: true` is passed, the response

  1019     // data will be passed through the `reset` method instead of `set`.

  1020     fetch: function(options) {

  1021       options = _.extend({parse: true}, options);

  1022       var success = options.success;

  1023       var collection = this;

  1024       options.success = function(resp) {

  1025         var method = options.reset ? 'reset' : 'set';

  1026         collection[method](resp, options);

  1027         if (success) success.call(options.context, collection, resp, options);

  1028         collection.trigger('sync', collection, resp, options);

  1029       };

  1030       wrapError(this, options);

  1031       return this.sync('read', this, options);

  1032     },

  1033 

  1034     // Create a new instance of a model in this collection. Add the model to the

  1035     // collection immediately, unless `wait: true` is passed, in which case we

  1036     // wait for the server to agree.

  1037     create: function(model, options) {

  1038       options = options ? _.clone(options) : {};

  1039       var wait = options.wait;

  1040       model = this._prepareModel(model, options);

  1041       if (!model) return false;

  1042       if (!wait) this.add(model, options);

  1043       var collection = this;

  1044       var success = options.success;

  1045       options.success = function(model, resp, callbackOpts) {

  1046         if (wait) collection.add(model, callbackOpts);

  1047         if (success) success.call(callbackOpts.context, model, resp, callbackOpts);

  1048       };

  1049       model.save(null, options);

  1050       return model;

  1051     },

  1052 

  1053     // **parse** converts a response into a list of models to be added to the

  1054     // collection. The default implementation is just to pass it through.

  1055     parse: function(resp, options) {

  1056       return resp;

  1057     },

  1058 

  1059     // Create a new collection with an identical list of models as this one.

  1060     clone: function() {

  1061       return new this.constructor(this.models, {

  1062         model: this.model,

  1063         comparator: this.comparator

  1064       });

  1065     },

  1066 

  1067     // Define how to uniquely identify models in the collection.

  1068     modelId: function (attrs) {

  1069       return attrs[this.model.prototype.idAttribute || 'id'];

  1070     },

  1071 

  1072     // Private method to reset all internal state. Called when the collection

  1073     // is first initialized or reset.

  1074     _reset: function() {

  1075       this.length = 0;

  1076       this.models = [];

  1077       this._byId  = {};

  1078     },

  1079 

  1080     // Prepare a hash of attributes (or other model) to be added to this

  1081     // collection.

  1082     _prepareModel: function(attrs, options) {

  1083       if (this._isModel(attrs)) {

  1084         if (!attrs.collection) attrs.collection = this;

  1085         return attrs;

  1086       }

  1087       options = options ? _.clone(options) : {};

  1088       options.collection = this;

  1089       var model = new this.model(attrs, options);

  1090       if (!model.validationError) return model;

  1091       this.trigger('invalid', this, model.validationError, options);

  1092       return false;

  1093     },

  1094 

  1095     // Internal method called by both remove and set.

  1096     _removeModels: function(models, options) {

  1097       var removed = [];

  1098       for (var i = 0; i < models.length; i++) {

  1099         var model = this.get(models[i]);

  1100         if (!model) continue;

  1101 

  1102         var index = this.indexOf(model);

  1103         this.models.splice(index, 1);

  1104         this.length--;

  1105 

  1106         if (!options.silent) {

  1107           options.index = index;

  1108           model.trigger('remove', model, this, options);

  1109         }

  1110 

  1111         removed.push(model);

  1112         this._removeReference(model, options);

  1113       }

  1114       return removed.length ? removed : false;

  1115     },

  1116 

  1117     // Method for checking whether an object should be considered a model for

  1118     // the purposes of adding to the collection.

  1119     _isModel: function (model) {

  1120       return model instanceof Model;

  1121     },

  1122 

  1123     // Internal method to create a model's ties to a collection.

  1124     _addReference: function(model, options) {

  1125       this._byId[model.cid] = model;

  1126       var id = this.modelId(model.attributes);

  1127       if (id != null) this._byId[id] = model;

  1128       model.on('all', this._onModelEvent, this);

  1129     },

  1130 

  1131     // Internal method to sever a model's ties to a collection.

  1132     _removeReference: function(model, options) {

  1133       delete this._byId[model.cid];

  1134       var id = this.modelId(model.attributes);

  1135       if (id != null) delete this._byId[id];