modify admin/conference_controller_spec and not authorized error messages

app/controllers/admin/base_controller.rb

@@ -10,7 +10,7 @@ module Admin
       unless (current_user.has_role? :organizer, :any) || (current_user.has_role? :cfp, :any) ||
              (current_user.has_role? :info_desk, :any) || (current_user.has_role? :organization_admin, :any) ||
              (current_user.has_role? :volunteers_coordinator, :any) || current_user.is_admin
-        raise CanCan::AccessDenied.new('You are not authorized to access this area!')
+        raise CanCan::AccessDenied.new('You are not authorized to access this page.')
       end
     end
   end

app/controllers/admin/conferences_controller.rb

@@ -72,11 +72,14 @@ module Admin
 
     def new
       @conference = Conference.new
+      @organizations = {}
+      Organization.all.each do |organization|
+        @organizations.store(organization.name, organization.id) if can? :create, Conference.new(organization: organization)
+      end
     end
 
     def create
       @conference = Conference.new(conference_params)
-      @conference.organization = Organization.find_or_create_by(name: 'organization')
       if @conference.save
         # user that creates the conference becomes organizer of that conference
         current_user.add_role :organizer, @conference

app/models/ability.rb

@@ -152,6 +152,7 @@ class Ability
     org_ids_for_organization_admin = Organization.with_role(:organization_admin, user).pluck(:id)
 
     can :manage, Organization, id: org_ids_for_organization_admin
+    can [:new], Conference
     can :manage, Conference, organization_id: org_ids_for_organization_admin
     conf_ids_for_organization_admin = []
     org_ids_for_organization_admin.each do |org_id|

app/views/admin/conferences/new.html.haml

@@ -6,6 +6,7 @@
                           input_html: { required: 'required' }
         = f.input :short_title, hint: "A short and unique handle for your conference, using only letters, numbers, underscores, and dashes. This will be used to identify your conference in URLs etc. Example: 'froscon2011'",
                                 input_html: { required: 'required', pattern: '[a-zA-Z0-9_-]+', title: 'Only letters, numbers, underscores, and dashes.' }, prepend: conferences_url + '/'
+        = f.input :organization, as: :select, collection: @organizations
       = f.inputs 'Scheduling' do
         = f.input :timezone, as: :time_zone, default: Time.zone.name, hint: 'Please select in what time zone your conference will take place.'
         = f.input :start_date, as: :string, input_html: { id: 'conference-start-datepicker', required: 'required' }