Validate room and start_time for EventSchedule

Don't allow an event to be scheduled outside of it's track's room and
time slot

app/models/event_schedule.rb

@@ -12,6 +12,8 @@ class EventSchedule < ActiveRecord::Base
   validates :event, uniqueness: { scope: :schedule }
   validate :start_after_end_hour
   validate :start_before_start_hour
+  validate :room_of_track
+  validate :during_track
 
   scope :confirmed, -> { joins(:event).where('state = ?', 'confirmed') }
   scope :canceled, -> { joins(:event).where('state = ?', 'canceled') }
@@ -52,4 +54,26 @@ class EventSchedule < ActiveRecord::Base
   def conference_id
     schedule.program.conference_id
   end
+
+  ##
+  # Validates that the event is scheduled in the same room as it's track
+  #
+  def room_of_track
+    if event && event.track.try(:room) && event.track.room != room
+      errors.add(:room, "must be the same as the track's room (#{event.track.room.name})")
+    end
+  end
+
+  ##
+  # Validates that the event is scheduled within it's track's time slot
+  #
+  def during_track
+    if event && event.track.try(:start_date) && event.track.start_date > start_time
+      errors.add(:start_time, "can't be before the track's start date (#{event.track.start_date})")
+    end
+
+    if event && event.track.try(:end_date) && event.track.end_date + 1.day < end_time
+      errors.add(:end_time, "can't be after the track's end date (#{event.track.end_date})")
+    end
+  end
 end