class app.AppCache  $.extend @prototype, Events   @isEnabled: ->    try      applicationCache and applicationCache.status isnt applicationCache.UNCACHED    catch   constructor: ->    @cache = applicationCache    @notifyUpdate = true    @onUpdateReady() if @cache.status is @cache.UPDATEREADY     $.on @cache, 'progress', @onProgress    $.on @cache, 'updateready', @onUpdateReady   update: ->    @notifyUpdate = true    @notifyProgress = true    try @cache.update() catch    return   updateInBackground: ->    @notifyUpdate = false    @notifyProgress = false    try @cache.update() catch    return   reload: ->    $.on @cache, 'updateready noupdate error', -> window.location = '/'    @notifyUpdate = false    @notifyProgress = true    try @cache.update() catch    return   onProgress: (event) =>    @trigger 'progress', event if @notifyProgress    return   onUpdateReady: =>    @trigger 'updateready' if @notifyUpdate    return