1 files changed, 21 insertions, 0 deletions
diff --git a/app/models/group.rb b/app/models/group.rb
index e0cfaab..6c65f70 100644
--- a/app/models/group.rb
+++ b/app/models/group.rb
@@ -5,7 +5,28 @@ class Group < ActiveRecord::Base
   has_many :group_permissions, :dependent => :destroy
   has_many :permittances, :foreign_key => :target_group_id, :class_name => "GroupPermission", :dependent => :destroy
 
+  validates :name,
+            :presence => true
+
   def to_s
     self.name
   end
+
+  def permission_targets(permission)
+    group_permissions.where(:permission => permission).pluck(:target_group_id)
+  end
+
+  def has_permission(target_type, target_id, permission)
+    target_group_ids = GroupMembership.where(:item_id => target_id, :item_type => target_type).pluck(:group_id)
+    return group_permissions.where(:permission => permission, :target_group_id => target_group_ids).first != nil
+  end
+
+  def self.union(sets=[])
+    group_ids = []
+    sets.each do |set|
+      group_ids = group_ids + set
+    end
+
+    return group_ids.uniq
+  end
 end