fix for buggy migration 20140801080705

db/migrate/20140820124117_undo_wrong_migration20140801080705_add_users_to_events.rb

@@ -0,0 +1,51 @@
+class UndoWrongMigration20140801080705AddUsersToEvents < ActiveRecord::Migration
+  class TempEvent < ActiveRecord::Base
+    self.table_name = 'events'
+  end
+
+  class TempUser < ActiveRecord::Base
+    self.table_name = 'users'
+  end
+
+  class TempEventUser < ActiveRecord::Base
+    self.table_name = 'event_users'
+    belongs_to :temp_event
+    belongs_to :temp_user
+    attr_accessible :event_id, :user_id, :event_role
+  end
+
+  class Version < ActiveRecord::Base
+    self.table_name = 'versions'
+  end
+
+  def up
+    if ActiveRecord::Migrator.get_all_versions.include?20140801080705
+      user_deleted = TempUser.find_by(email: 'deleted@localhost.osem')
+
+      TempEvent.all.each do |event|
+        whodunnit = Version.find_by(item_type: 'Event', item_id: event.id, event: 'create').whodunnit
+        original_user = TempUser.find_by(id: whodunnit)
+
+        if original_user.blank?
+          original_submitter = user_deleted
+        else
+          original_submitter = original_user
+        end
+
+        # Substitute submitter record
+        submitter = TempEventUser.find_by(event_id: event.id, event_role: 'submitter')
+        submitter.user_id = original_submitter.id
+        submitter.save!
+
+        # Substitute speaker record
+        speaker = TempEventUser.find_by(event_id: event.id, event_role: 'speaker')
+        speaker.user_id = original_submitter.id
+        speaker.save!
+      end
+    end
+  end
+
+  def down
+    raise ActiveRecord::IrreversibleMigration.new('Cannot reverse migration.')
+  end
+end