Improve announcements UI

core/admin.py

@@ -154,6 +154,14 @@ class AnnouncementAdmin(admin.ModelAdmin):
     search_fields = ["title", "summary", "body"]
     actions = [publish_selected_announcements, unpublish_selected_announcements]
 
+    def get_readonly_fields(self, request, obj=None):
+        # published_at is set automatically the first time an announcement is
+        # published (see Announcement.save()) - once set, edit it via
+        # unpublish/republish rather than by hand.
+        if obj is not None and obj.published_at is not None:
+            return ["published_at"]
+        return []
+
 
 @admin.register(PlayerAnnouncementState)
 class PlayerAnnouncementStateAdmin(admin.ModelAdmin):

core/migrations/0017_alter_announcement_body.py

@@ -0,0 +1,20 @@
+# Generated by Django 5.2.17 on 2026-08-14 11:42
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("core", "0016_gamesettings_daily_goals_completion_bonus_ap"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="announcement",
+            name="body",
+            field=models.TextField(
+                help_text="Supports Markdown (bold, links, lists, etc.)."
+            ),
+        ),
+    ]

core/models.py

@@ -5,6 +5,7 @@
 from django.core.files.storage import Storage
 from django.db import models
 from django.urls import reverse
+from django.utils import timezone
 from django.utils.deconstruct import deconstructible
 
 
@@ -233,7 +234,7 @@ def as_dict(cls):
 class Announcement(models.Model):
     title = models.CharField(max_length=200)
     summary = models.CharField(max_length=300, blank=True)
-    body = models.TextField()
+    body = models.TextField(help_text="Supports Markdown (bold, links, lists, etc.).")
     is_published = models.BooleanField(default=False)
     published_at = models.DateTimeField(null=True, blank=True, db_index=True)
     created_at = models.DateTimeField(auto_now_add=True)
@@ -247,6 +248,11 @@ class Meta:
     def __str__(self):
         return self.title
 
+    def save(self, *args, **kwargs):
+        if self.is_published and self.published_at is None:
+            self.published_at = timezone.now()
+        super().save(*args, **kwargs)
+
 
 class PlayerAnnouncementState(models.Model):
     player = models.ForeignKey(

core/tests.py

@@ -3,13 +3,16 @@
 
 from django.core.exceptions import ValidationError
 from django.test import SimpleTestCase, TestCase, override_settings
+from django.contrib import admin as django_admin
 from django.contrib.auth import get_user_model
 from rest_framework import status
 from rest_framework.test import APITestCase
 
+from django.utils import timezone
+
 from core.checks import REQUIRED_PROD_SETTINGS, check_required_prod_settings
-from core.admin import FeatureFlagForm
-from core.models import FeatureFlag, GameSettings
+from core.admin import AnnouncementAdmin, FeatureFlagForm
+from core.models import Announcement, FeatureFlag, GameSettings
 from users.services.login_services import (
     calculate_daily_login_reward,
     LOGIN_STATE_ALREADY_LOGGED_TODAY,
@@ -298,3 +301,57 @@ def test_editing_existing_flag_keeps_its_own_key_selectable(self, mock_path):
         choice_keys = [key for key, _ in form.fields["key"].choices]
         self.assertIn("tasksFeature", choice_keys)
         self.assertNotIn("activityList", choice_keys)
+
+
+class AnnouncementSaveTest(TestCase):
+    def test_publishing_sets_published_at_if_unset(self):
+        announcement = Announcement.objects.create(
+            title="Hi", body="Body", is_published=True
+        )
+        self.assertIsNotNone(announcement.published_at)
+
+    def test_publishing_does_not_overwrite_existing_published_at(self):
+        original = timezone.now() - timezone.timedelta(days=3)
+        announcement = Announcement.objects.create(
+            title="Hi", body="Body", is_published=True, published_at=original
+        )
+        self.assertEqual(announcement.published_at, original)
+
+    def test_creating_unpublished_leaves_published_at_unset(self):
+        announcement = Announcement.objects.create(
+            title="Hi", body="Body", is_published=False
+        )
+        self.assertIsNone(announcement.published_at)
+
+    def test_saving_again_after_publish_does_not_change_published_at(self):
+        announcement = Announcement.objects.create(
+            title="Hi", body="Body", is_published=True
+        )
+        first_published_at = announcement.published_at
+
+        announcement.title = "Updated"
+        announcement.save()
+
+        self.assertEqual(announcement.published_at, first_published_at)
+
+
+class AnnouncementAdminReadonlyFieldsTest(TestCase):
+    def setUp(self):
+        self.admin = AnnouncementAdmin(Announcement, django_admin.site)
+
+    def test_published_at_editable_when_unset(self):
+        announcement = Announcement.objects.create(title="Hi", body="Body")
+        self.assertNotIn(
+            "published_at", self.admin.get_readonly_fields(None, announcement)
+        )
+
+    def test_published_at_readonly_once_set(self):
+        announcement = Announcement.objects.create(
+            title="Hi", body="Body", is_published=True
+        )
+        self.assertIn(
+            "published_at", self.admin.get_readonly_fields(None, announcement)
+        )
+
+    def test_published_at_editable_for_new_unsaved_announcement(self):
+        self.assertNotIn("published_at", self.admin.get_readonly_fields(None, None))