add codify template tag to turn confirmation ids int something more o…

…fficial looking

rapidsms_xforms/templatetags/messages.py

@@ -1,11 +1,62 @@
 from django import template
+from django.utils.safestring import mark_safe
 
 # 
 # Contains simple filters that may be useful within messages processing.
 #
 
 def multiply(input, property):
+    """
+    Just multiplies two values together.  Surprisingly this isn't possible in normal templates.
+    """
     return "%.2f" % (float(input) * float(property))
 
 register = template.Library()
 register.filter('multiply', multiply)
+
+def in_base_36(number):
+    if not isinstance(number, (int, long)):
+        raise TypeError('number must be an integer')
+    if number < 0:
+        raise ValueError('number must be positive')
+
+    alphabet = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ'
+
+    base36 = ''
+    while number:
+        number, i = divmod(number, 36)
+        base36 = alphabet[i] + base36
+
+    return base36 or alphabet[0]
+
+def codify(input, property=None):
+    """
+    Turns a numerical id into something slightly more impressive.  Specifically a 4 letter
+    base 36 item with an optional prefix, zero padded.  This will work up to about 1.5M
+    entries, at which point it will start skipping to six letters instead up to ~2B, then
+    just echo the raw value in base 36.
+
+    IE, if you pass in 3688, this will return 00A8.  If you pass in a prefix of S, then
+    the value will be S00A8.
+    """
+    val = int(input)
+
+    # values that can be represented in 4 letters
+    if val <= 1679615:
+        based = in_base_36(val)
+        based = "0" * (4-len(based)) + based
+    # things that are six letters
+    elif val <= 2176782335:
+        based = in_base_36(val)
+        based = "0" * (6-len(based)) + based
+    # huge!
+    else:
+        based = in_base_36(val)
+
+    if property:
+        return property + based
+    else:
+        return based
+
+register.filter('codify', codify)
+codify.is_safe = True

rapidsms_xforms/tests.py

@@ -391,7 +391,25 @@ def testConfirmationId(self):
         self.assertEquals(5, submission6.confirmation_id)
 
     def testTemplateResponse(self):
-        # first test no template
+        # codify the confirmation id
+        self.xform.response = 'Your confirmation id is: {{ confirmation_id|codify:"SA" }}'
+        self.xform.save()
+
+        submission = self.xform.process_sms_submission(IncomingMessage(None, "survey male 10"))
+
+        # should be safe to use a static value since we are the first test
+        self.failUnlessEqual(submission.response, "Your confirmation id is: SA0001")
+
+        # no prefix
+        self.xform.response = 'Your confirmation id is: {{ confirmation_id|codify }}'
+        self.xform.save()
+
+        submission = self.xform.process_sms_submission(IncomingMessage(None, "survey male 10"))
+
+        # should be safe to use a static value since we are the first test
+        self.failUnlessEqual(submission.response, "Your confirmation id is: 0002")
+
+        # now test no template
         self.xform.response = "Thanks for sending your message"
         self.xform.save()
 
@@ -404,7 +422,7 @@ def testTemplateResponse(self):
         self.xform.save()
 
         submission = self.xform.process_sms_submission(IncomingMessage(None, "survey male 10"))
-        self.failUnlessEqual(submission.response, "You recorded an age of 10 and a gender of male.  Your confirmation id is 2.")
+        self.failUnlessEqual(submission.response, "You recorded an age of 10 and a gender of male.  Your confirmation id is 4.")
 
         # if they insert a command that isn't there, it should just be empty
         self.xform.response = "You recorded an age of {{ age }} and a gender of {{ gender }}.  {{ not_there }} Thanks."