Fix #2772: Topics set as mod+ can't be reverted to public ones.

app/helpers/forum_topics_helper.rb

@@ -4,12 +4,6 @@ module ForumTopicsHelper
   end
 
   def available_min_user_levels
-    if CurrentUser.is_admin?
-      [["Moderator", User::Levels::MODERATOR], ["Admin", User::Levels::ADMIN]]
-    elsif CurrentUser.is_moderator?
-      [["Moderator", User::Levels::MODERATOR]]
-    else
-      []
-    end
+    ForumTopic::MIN_LEVELS.select { |name, level| level <= CurrentUser.level }.to_a
   end
 end

app/models/forum_topic.rb

@@ -5,6 +5,12 @@ class ForumTopic < ActiveRecord::Base
     2 => "Bugs & Features"
   }
 
+  MIN_LEVELS = {
+    None: 0,
+    Moderator: User::Levels::MODERATOR,
+    Admin: User::Levels::ADMIN,
+  }
+
   attr_accessible :title, :original_post_attributes, :category_id, :as => [:member, :builder, :gold, :platinum, :janitor, :moderator, :admin, :default]
   attr_accessible :is_sticky, :is_locked, :is_deleted, :min_level, :as => [:admin, :moderator]
   belongs_to :creator, :class_name => "User"
@@ -18,7 +24,7 @@ class ForumTopic < ActiveRecord::Base
   validates_presence_of :title, :creator_id
   validates_associated :original_post
   validates_inclusion_of :category_id, :in => CATEGORIES.keys
-  validates_inclusion_of :min_level, :in => [0, User::Levels::MODERATOR, User::Levels::ADMIN]
+  validates_inclusion_of :min_level, :in => MIN_LEVELS.values
   accepts_nested_attributes_for :original_post
   after_update :update_orignal_post
 

app/views/forum_topics/_form.html.erb

@@ -18,7 +18,7 @@
     <% end %>
 
     <% if CurrentUser.is_moderator? %>
-      <%= f.input :min_level, :as => :select, :collection => available_min_user_levels.to_a %>
+      <%= f.input :min_level, :include_blank => false, :collection => available_min_user_levels %>
       <%= f.input :is_sticky, :label => "Sticky" %>
       <%= f.input :is_locked, :label => "Locked" %>
     <% end %>