Implement primary answer management with HTMX support, including form for selecting or creating answers and display templates

anatomy/forms.py

@@ -290,4 +290,19 @@ class ExamGroupsForm(ExamGroupsFormMixin):
 class SuggestIncorrectAnswerForm(ModelForm):
     class Meta:
         model = AnatomyQuestion
-        fields = ["answer_suggest_incorrect"]
+        fields = ["answer_suggest_incorrect"]
+
+
+class PrimaryAnswerForm(Form):
+    existing_answer = ChoiceField(required=False, choices=[], label="Use existing answer")
+    new_answer = CharField(required=False, widget=Textarea(attrs={"rows":3}), label="Or create new primary answer")
+
+    def __init__(self, *args, **kwargs):
+        question = kwargs.pop("question", None)
+        super().__init__(*args, **kwargs)
+        choices = [("", "-- choose existing --")]
+        if question is not None:
+            # Only include existing non-proposed CORRECT answers, ordered by answer text
+            for a in question.answers.filter(proposed=False, status=Answer.MarkOptions.CORRECT).order_by('answer'):
+                choices.append((str(a.pk), a.answer))
+        self.fields["existing_answer"].choices = choices