Add authorisation models.

Add EventAuthorisation model + migrations

Add authorised property to Event.

Add appropriate tests

RIGS/models.py

@@ -385,6 +385,10 @@ class Event(models.Model, RevisionMixin):
     def confirmed(self):
         return (self.status == self.BOOKED or self.status == self.CONFIRMED)
 
+    @property
+    def authorised(self):
+        return self.authroisations.latest('created_at').amount >= self.total
+
     @property
     def has_start_time(self):
         return self.start_time is not None
@@ -501,6 +505,30 @@ class EventCrew(models.Model):
     notes = models.TextField(blank=True, null=True)
 
 
+class EventAuthorisation(models.Model):
+    event = models.ForeignKey('Event', related_name='authroisations')
+    email = models.EmailField()
+    name = models.CharField(max_length=255)
+    uni_id = models.CharField(max_length=10, blank=True, null=True, verbose_name="University ID")
+    account_code = models.CharField(max_length=50, blank=True, null=True)
+    po = models.CharField(max_length=255, blank=True, null=True, verbose_name="purchase order")
+    amount = models.DecimalField(max_digits=10, decimal_places=2, verbose_name="authorisation amount")
+    created_at = models.DateTimeField(auto_now_add=True)
+
+    def clean(self):
+        if self.amount != self.event.total:
+            raise ValidationError("The amount authorised must equal the total for the event")
+        if self.event.organisation and self.event.organisation.union_account:
+            # Is a union account, requires username and account number
+            if self.uni_id is None or self.uni_id == "" or self.account_code is None or self.account_code == "":
+                raise ValidationError("Internal clients require a University ID number and an account code")
+        else:
+            # Is an external client, only requires PO
+            if self.po is None or self.po == "":
+                raise ValidationError("External clients require a Purchase Order number")
+        return super(EventAuthorisation, self).clean()
+
+
 @python_2_unicode_compatible
 class Invoice(models.Model):
     event = models.OneToOneField('Event')