lib/rails-canhaz/canhaz_permission.rb in rails-canhaz-0.1.2 vs lib/rails-canhaz/canhaz_permission.rb in rails-canhaz-0.2.0

@@ -22,6 +22,45 @@
       :permission_name  => permission
     )
     results.first
   end
 
+  # Gets the permissions for multiple subjects
+  #
+  # @param subjects [Array] an array of subjects
+  # @param permission [Hash, String] The identifier of the permission
+  # @param objects [Array] an array of objects
+  # @return [Hash] A Hash of permissions, the key is the id of the object, the value is an array of objects that match
+  def self.can?(subjects, permission, objects)
+
+    return {} if subjects.size == 0 or objects.size == 0
+
+    raise  NotUniqueClasses if subjects.group_by { |s| s.class }.size > 1
+    raise  NotUniqueClasses if objects.group_by { |s| s.class }.size > 1
+
+    subject_ids = subjects.collect { |s| s.id }
+    object_ids = objects.collect{ |o| o.id }
+
+    results = CanHazPermission.where(
+      [
+        'csubject_id IN (?) AND cobject_id IN(?) AND csubject_type = ? AND cobject_type = ? AND permission_name = ?',
+        subject_ids,
+        object_ids,
+        subjects.first.class.to_s,
+        objects.first.class.to_s,
+        permission
+      ]
+    )
+
+    h = {}
+
+    subjects.each do |subject|
+      # Get the ids of the objects that matched
+      matching = results.find_all { |result| result.csubject_id == subject.id}.collect { |c| c.cobject_id }
+      h[subject.id] = objects.find_all { |object| matching.include? object.id }
+    end
+
+    h
+
+  end
+
 end