[Mascots] Fix handling of app names with spaces in them

Use comma as a separator instead.
Closes #551

app/models/application_record.rb

@@ -322,9 +322,9 @@ class ApplicationRecord < ActiveRecord::Base
       # The `<attribute>=` setter parses strings into an array using the
       # `parse` regex. The resulting strings can be converted to another type
       # with the `cast` option.
-      def array_attribute(name, parse: /[^[:space:]]+/, cast: :itself)
+      def array_attribute(name, parse: /[^[:space:]]+/, join_character: " ", cast: :itself)
         define_method "#{name}_string" do
-          send(name).join(" ")
+          send(name).join(join_character)
         end
 
         define_method "#{name}_string=" do |value|

app/models/mascot.rb

@@ -1,7 +1,7 @@
 class Mascot < ApplicationRecord
   belongs_to_creator
 
-  array_attribute :available_on
+  array_attribute :available_on, parse: /[^,]+/, join_character: ","
   attr_accessor :mascot_file
 
   validates :display_name, :background_color, :artist_url, :artist_name, presence: true

app/views/mascots/_form.html.erb

@@ -5,7 +5,7 @@
   <%= f.input :background_color %>
   <%= f.input :artist_url %>
   <%= f.input :artist_name %>
-  <%= f.input :available_on_string, label: "Available on" %>
+  <%= f.input :available_on_string, label: "Available on", hint: "Separated by a comma, don't include spaces before/after" %>
   <%= f.input :active %>
   <%= f.submit %>
 <% end %>