Include available states to transition to.

bikeshop_project/bike/models.py

@@ -78,7 +78,8 @@ class Bike(models.Model):
         return self.stolen is False and self.cpic_searched_at is not None and self.serial_number is not None
 
     def can_claim(self):
-        return self.claimed_by is None or not (self.claimed_by is not None and self.last_worked_on > timezone.now() - timedelta(
+        return self.claimed_by is None or not (
+            self.claimed_by is not None and self.last_worked_on > timezone.now() - timedelta(
                 weeks=4)) or self.last_worked_on is None
 
     def can_purchase(self):
@@ -122,3 +123,10 @@ class Bike(models.Model):
     @transition(field=state, source=[BikeState.ASSESSED, BikeState.RECEIVED], conditions=[can_transfer_to_police])
     def transfer_to_police(self):
         pass
+
+    @property
+    def available_states(self):
+        states = [state_transition.name
+                  for state_transition in self.get_available_state_transitions()]
+
+        return states

bikeshop_project/bike/serializers.py

@@ -10,3 +10,4 @@ class BikeSerializer(serializers.HyperlinkedModelSerializer):
 
     created_at = serializers.ReadOnlyField()
     state = serializers.ReadOnlyField()
+    available_states = serializers.ReadOnlyField()