From 9650c7d0abdba76205715468f05415948608e10c Mon Sep 17 00:00:00 2001
From: Dean Menezes <dmm3297@my.utexas.edu>
Date: Sun, 1 Mar 2026 15:24:59 -0600
Subject: [PATCH 01/14] feat: add user timezone setting with auto-detection

Add timezone field to UserProfile that allows users to view all timestamps in their local timezone:
- CharField with blank default (uses server time America/New_York when blank)
- JavaScript auto-detection using Intl API to prefill detected timezone
- TimezoneMiddleware activates user's timezone per-request using zoneinfo
- All existing |date template filters automatically respect the activated timezone
---
 core/middleware.py                           | 21 ++++++++++++++++++++
 core/migrations/0064_userprofile_timezone.py | 18 +++++++++++++++++
 core/models.py                               |  7 +++++++
 core/templates/core/userprofile_form.html    | 16 +++++++++++++++
 core/views.py                                |  2 ++
 otisweb/settings.py                          |  1 +
 6 files changed, 65 insertions(+)
 create mode 100644 core/migrations/0064_userprofile_timezone.py

diff --git a/core/middleware.py b/core/middleware.py
index e9587775f..cc0da4fd5 100644
--- a/core/middleware.py
+++ b/core/middleware.py
@@ -1,5 +1,7 @@
 from typing import Callable
 
+import zoneinfo
+
 from django.core.cache import cache
 from django.http.request import HttpRequest
 from django.http.response import HttpResponse
@@ -25,3 +27,22 @@ def __call__(self, request: HttpRequest):
             up.last_seen = timezone.now()
             up.save(update_fields=("last_seen",))
         return response
+
+
+class TimezoneMiddleware:
+    def __init__(self, get_response: Callable[[HttpRequest], HttpResponse]):
+        self.get_response = get_response
+
+    def __call__(self, request: HttpRequest):
+        if request.user.is_authenticated:
+            user_timezone = request.user.profile.timezone
+            if user_timezone:
+                try:
+                    timezone.activate(zoneinfo.ZoneInfo(user_timezone))
+                except zoneinfo.ZoneInfoNotFoundError:
+                    timezone.deactivate()
+            else:
+                timezone.deactivate()
+        response = self.get_response(request)
+        timezone.deactivate()
+        return response
diff --git a/core/migrations/0064_userprofile_timezone.py b/core/migrations/0064_userprofile_timezone.py
new file mode 100644
index 000000000..811e76463
--- /dev/null
+++ b/core/migrations/0064_userprofile_timezone.py
@@ -0,0 +1,18 @@
+# Generated by Django 5.2.11 on 2026-03-01 21:24
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0063_alter_userprofile_dynamic_progress_and_more'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='userprofile',
+            name='timezone',
+            field=models.CharField(blank=True, default='', help_text='Your local time zone for displaying timestamps. Leave blank to use server time (America/New_York).', max_length=63, verbose_name='Time zone'),
+        ),
+    ]
diff --git a/core/models.py b/core/models.py
index 948c7b342..c065b7709 100644
--- a/core/models.py
+++ b/core/models.py
@@ -298,6 +298,13 @@ class UserProfile(models.Model):
         help_text="Hide all hints from the problem archive (ARCH).",
         default=False,
     )
+    timezone = models.CharField(
+        max_length=63,
+        blank=True,
+        default="",
+        verbose_name="Time zone",
+        help_text="Your local time zone for displaying timestamps. Leave blank to use server time (America/New_York).",
+    )
 
     email_on_announcement = models.BooleanField(
         verbose_name="Receive emails for announcements",
diff --git a/core/templates/core/userprofile_form.html b/core/templates/core/userprofile_form.html
index e3f912508..9548eb559 100644
--- a/core/templates/core/userprofile_form.html
+++ b/core/templates/core/userprofile_form.html
@@ -35,4 +35,20 @@ <h1>Advanced settings</h1>
       <button type="submit" class="btn btn-success">Update settings</button>
     </div>
   </form>
+  <script>
+    // Auto-detect and prefill timezone if field is empty
+    document.addEventListener('DOMContentLoaded', function() {
+      const timezoneField = document.getElementById('id_timezone');
+      if (timezoneField && !timezoneField.value) {
+        try {
+          const detectedTimezone = Intl.DateTimeFormat().resolvedOptions().timeZone;
+          if (detectedTimezone) {
+            timezoneField.value = detectedTimezone;
+          }
+        } catch (error) {
+          console.log('Could not auto-detect timezone:', error);
+        }
+      }
+    });
+  </script>
 {% endblock layout-content %}
diff --git a/core/views.py b/core/views.py
index d20e38e11..86441eb89 100644
--- a/core/views.py
+++ b/core/views.py
@@ -304,6 +304,7 @@ class UserProfileUpdateView(
         "show_portal_instructions",
         "show_unit_petitions",
         "disable_hints",
+        "timezone",
         "use_twemoji",
     )
     success_url = reverse_lazy("profile")
@@ -332,6 +333,7 @@ def get_context_data(self, **kwargs):
             form["show_portal_instructions"],
             form["show_unit_petitions"],
             form["disable_hints"],
+            form["timezone"],
             form["use_twemoji"],
         )
 
diff --git a/otisweb/settings.py b/otisweb/settings.py
index 597c117c3..4b46280d8 100644
--- a/otisweb/settings.py
+++ b/otisweb/settings.py
@@ -128,6 +128,7 @@
     "allauth.account.middleware.AccountMiddleware",
     "hijack.middleware.HijackUserMiddleware",
     "core.middleware.LastSeenMiddleware",
+    "core.middleware.TimezoneMiddleware",
 ]
 
 ROOT_URLCONF = "otisweb.urls"

From a665f0be65cdde2c7fa10539703911cbb5c5fe2b Mon Sep 17 00:00:00 2001
From: Dean Menezes <dmm3297@my.utexas.edu>
Date: Sun, 1 Mar 2026 15:26:35 -0600
Subject: [PATCH 02/14] style: apply ruff and djlint formatting

---
 core/middleware.py                           |  3 +--
 core/migrations/0064_userprofile_timezone.py | 15 +++++++----
 core/templates/core/userprofile_form.html    | 26 ++++++++++----------
 3 files changed, 24 insertions(+), 20 deletions(-)

diff --git a/core/middleware.py b/core/middleware.py
index cc0da4fd5..4034a5182 100644
--- a/core/middleware.py
+++ b/core/middleware.py
@@ -1,6 +1,5 @@
-from typing import Callable
-
 import zoneinfo
+from typing import Callable
 
 from django.core.cache import cache
 from django.http.request import HttpRequest
diff --git a/core/migrations/0064_userprofile_timezone.py b/core/migrations/0064_userprofile_timezone.py
index 811e76463..6cc92a4c9 100644
--- a/core/migrations/0064_userprofile_timezone.py
+++ b/core/migrations/0064_userprofile_timezone.py
@@ -4,15 +4,20 @@
 
 
 class Migration(migrations.Migration):
-
     dependencies = [
-        ('core', '0063_alter_userprofile_dynamic_progress_and_more'),
+        ("core", "0063_alter_userprofile_dynamic_progress_and_more"),
     ]
 
     operations = [
         migrations.AddField(
-            model_name='userprofile',
-            name='timezone',
-            field=models.CharField(blank=True, default='', help_text='Your local time zone for displaying timestamps. Leave blank to use server time (America/New_York).', max_length=63, verbose_name='Time zone'),
+            model_name="userprofile",
+            name="timezone",
+            field=models.CharField(
+                blank=True,
+                default="",
+                help_text="Your local time zone for displaying timestamps. Leave blank to use server time (America/New_York).",
+                max_length=63,
+                verbose_name="Time zone",
+            ),
         ),
     ]
diff --git a/core/templates/core/userprofile_form.html b/core/templates/core/userprofile_form.html
index 9548eb559..b54ddb302 100644
--- a/core/templates/core/userprofile_form.html
+++ b/core/templates/core/userprofile_form.html
@@ -36,19 +36,19 @@ <h1>Advanced settings</h1>
     </div>
   </form>
   <script>
-    // Auto-detect and prefill timezone if field is empty
-    document.addEventListener('DOMContentLoaded', function() {
-      const timezoneField = document.getElementById('id_timezone');
-      if (timezoneField && !timezoneField.value) {
-        try {
-          const detectedTimezone = Intl.DateTimeFormat().resolvedOptions().timeZone;
-          if (detectedTimezone) {
-            timezoneField.value = detectedTimezone;
+      // Auto-detect and prefill timezone if field is empty
+      document.addEventListener('DOMContentLoaded', function() {
+          const timezoneField = document.getElementById('id_timezone');
+          if (timezoneField && !timezoneField.value) {
+              try {
+                  const detectedTimezone = Intl.DateTimeFormat().resolvedOptions().timeZone;
+                  if (detectedTimezone) {
+                      timezoneField.value = detectedTimezone;
+                  }
+              } catch (error) {
+                  console.log('Could not auto-detect timezone:', error);
+              }
           }
-        } catch (error) {
-          console.log('Could not auto-detect timezone:', error);
-        }
-      }
-    });
+      });
   </script>
 {% endblock layout-content %}

From 0d7233f23532f62a11850cff1d29d2f9a930e905 Mon Sep 17 00:00:00 2001
From: Dean Menezes <dmm3297@my.utexas.edu>
Date: Sun, 1 Mar 2026 15:32:04 -0600
Subject: [PATCH 03/14] fix: use getattr to satisfy pyright type checking in
 TimezoneMiddleware

---
 core/middleware.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/core/middleware.py b/core/middleware.py
index 4034a5182..5e5209d10 100644
--- a/core/middleware.py
+++ b/core/middleware.py
@@ -34,7 +34,9 @@ def __init__(self, get_response: Callable[[HttpRequest], HttpResponse]):
 
     def __call__(self, request: HttpRequest):
         if request.user.is_authenticated:
-            user_timezone = request.user.profile.timezone
+            user_timezone = getattr(
+                getattr(request.user, "profile", None), "timezone", ""
+            )
             if user_timezone:
                 try:
                     timezone.activate(zoneinfo.ZoneInfo(user_timezone))

From b48586cb85fab00e4b704f02b20f0024da2418fa Mon Sep 17 00:00:00 2001
From: Dean Menezes <dmm3297@my.utexas.edu>
Date: Sun, 1 Mar 2026 15:50:35 -0600
Subject: [PATCH 04/14] refactor: use get_or_create for UserProfile access in
 TimezoneMiddleware

Replace nested getattr with get_or_create for better readability,
matching the pattern used in LastSeenMiddleware above it.
---
 core/middleware.py | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/core/middleware.py b/core/middleware.py
index 5e5209d10..1bdbf0399 100644
--- a/core/middleware.py
+++ b/core/middleware.py
@@ -34,12 +34,10 @@ def __init__(self, get_response: Callable[[HttpRequest], HttpResponse]):
 
     def __call__(self, request: HttpRequest):
         if request.user.is_authenticated:
-            user_timezone = getattr(
-                getattr(request.user, "profile", None), "timezone", ""
-            )
-            if user_timezone:
+            up, _ = UserProfile.objects.get_or_create(user=request.user)
+            if up.timezone:
                 try:
-                    timezone.activate(zoneinfo.ZoneInfo(user_timezone))
+                    timezone.activate(zoneinfo.ZoneInfo(up.timezone))
                 except zoneinfo.ZoneInfoNotFoundError:
                     timezone.deactivate()
             else:

From c1eaea40ee285de8e77094fc1f5f3049009272cd Mon Sep 17 00:00:00 2001
From: Dean Menezes <dmm3297@my.utexas.edu>
Date: Sun, 1 Mar 2026 16:05:54 -0600
Subject: [PATCH 05/14] refactor: improve timezone feature based on feedback

- Add timezone validation to prevent invalid values in database
- Remove unnecessary timezone.deactivate() calls in middleware
- Move JavaScript to proper scripts block
- Change auto-fill to suggestion UX with dismissible alert
- Remove explicit UTC timezone display from pset queue
- Add comprehensive unit tests for timezone functionality
  - Validator tests for valid/invalid timezones
  - UserProfile model validation tests
  - Middleware tests for authenticated/unauthenticated users
  - Form integration tests
---
 core/middleware.py                            |   4 +-
 .../0065_alter_userprofile_timezone.py        |  19 +++
 core/models.py                                |  11 ++
 core/templates/core/userprofile_form.html     |  37 +++++-
 core/tests.py                                 | 116 ++++++++++++++++++
 .../templates/dashboard/pset_queue_list.html  |   4 +-
 6 files changed, 182 insertions(+), 9 deletions(-)
 create mode 100644 core/migrations/0065_alter_userprofile_timezone.py

diff --git a/core/middleware.py b/core/middleware.py
index 1bdbf0399..55b13f1b8 100644
--- a/core/middleware.py
+++ b/core/middleware.py
@@ -39,9 +39,7 @@ def __call__(self, request: HttpRequest):
                 try:
                     timezone.activate(zoneinfo.ZoneInfo(up.timezone))
                 except zoneinfo.ZoneInfoNotFoundError:
-                    timezone.deactivate()
-            else:
-                timezone.deactivate()
+                    pass  # Fall back to default timezone
         response = self.get_response(request)
         timezone.deactivate()
         return response
diff --git a/core/migrations/0065_alter_userprofile_timezone.py b/core/migrations/0065_alter_userprofile_timezone.py
new file mode 100644
index 000000000..65a26e503
--- /dev/null
+++ b/core/migrations/0065_alter_userprofile_timezone.py
@@ -0,0 +1,19 @@
+# Generated by Django 5.2.11 on 2026-03-01 22:05
+
+import core.models
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0064_userprofile_timezone'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='userprofile',
+            name='timezone',
+            field=models.CharField(blank=True, default='', help_text='Your local time zone for displaying timestamps. Leave blank to use server time (America/New_York).', max_length=63, validators=[core.models.validate_timezone], verbose_name='Time zone'),
+        ),
+    ]
diff --git a/core/models.py b/core/models.py
index c065b7709..352ac86b8 100644
--- a/core/models.py
+++ b/core/models.py
@@ -2,9 +2,11 @@
 
 import datetime
 import os
+import zoneinfo
 from typing import Callable
 
 from django.contrib.auth import get_user_model
+from django.core.exceptions import ValidationError
 from django.db import models
 from django.db.models.manager import BaseManager
 from django.urls import reverse
@@ -14,6 +16,14 @@
 # Create your models here.
 
 
+def validate_timezone(value: str) -> None:
+    if value:  # blank is allowed
+        try:
+            zoneinfo.ZoneInfo(value)
+        except zoneinfo.ZoneInfoNotFoundError:
+            raise ValidationError(f"{value} is not a valid timezone")
+
+
 class Semester(models.Model):
     """Represents an academic semester/year/etc, e.g. "Fall 2017"
     or "Year III"."""
@@ -304,6 +314,7 @@ class UserProfile(models.Model):
         default="",
         verbose_name="Time zone",
         help_text="Your local time zone for displaying timestamps. Leave blank to use server time (America/New_York).",
+        validators=[validate_timezone],
     )
 
     email_on_announcement = models.BooleanField(
diff --git a/core/templates/core/userprofile_form.html b/core/templates/core/userprofile_form.html
index b54ddb302..1a6f4dc08 100644
--- a/core/templates/core/userprofile_form.html
+++ b/core/templates/core/userprofile_form.html
@@ -33,17 +33,46 @@ <h1>Display settings</h1>
       <h1>Advanced settings</h1>
       {% for field in advanced_fields %}{{ field|as_crispy_field }}{% endfor %}
       <button type="submit" class="btn btn-success">Update settings</button>
+      <div id="timezone-suggestion"
+           class="alert alert-info mt-2"
+           style="display: none">
+        Detected timezone: <strong id="detected-tz"></strong>
+        <button type="button"
+                class="btn btn-sm btn-primary ms-2"
+                id="use-detected-tz">Use this timezone</button>
+        <button type="button"
+                class="btn-close float-end"
+                aria-label="Close"
+                id="dismiss-tz-suggestion"></button>
+      </div>
     </div>
   </form>
+{% endblock layout-content %}
+{% block scripts %}
   <script>
-      // Auto-detect and prefill timezone if field is empty
+      // Show timezone suggestion if field is empty
       document.addEventListener('DOMContentLoaded', function() {
           const timezoneField = document.getElementById('id_timezone');
-          if (timezoneField && !timezoneField.value) {
+          const suggestionDiv = document.getElementById('timezone-suggestion');
+          const detectedTzSpan = document.getElementById('detected-tz');
+          const useButton = document.getElementById('use-detected-tz');
+          const dismissButton = document.getElementById('dismiss-tz-suggestion');
+
+          if (timezoneField && !timezoneField.value && suggestionDiv) {
               try {
                   const detectedTimezone = Intl.DateTimeFormat().resolvedOptions().timeZone;
                   if (detectedTimezone) {
-                      timezoneField.value = detectedTimezone;
+                      detectedTzSpan.textContent = detectedTimezone;
+                      suggestionDiv.style.display = 'block';
+
+                      useButton.addEventListener('click', function() {
+                          timezoneField.value = detectedTimezone;
+                          suggestionDiv.style.display = 'none';
+                      });
+
+                      dismissButton.addEventListener('click', function() {
+                          suggestionDiv.style.display = 'none';
+                      });
                   }
               } catch (error) {
                   console.log('Could not auto-detect timezone:', error);
@@ -51,4 +80,4 @@ <h1>Advanced settings</h1>
           }
       });
   </script>
-{% endblock layout-content %}
+{% endblock scripts %}
diff --git a/core/tests.py b/core/tests.py
index 031e004b6..ec6aca939 100644
--- a/core/tests.py
+++ b/core/tests.py
@@ -452,3 +452,119 @@ def test_set_default_artwork_action_single_unit_group():
     assert ug.artwork == "artwork/test-unit.png"
     assert ug.artwork_thumb_md == "artwork-thumb-md/test-unit.png"
     assert ug.artwork_thumb_sm == "artwork-thumb-sm/test-unit.png"
+
+
+@pytest.mark.django_db
+def test_timezone_validator():
+    from django.core.exceptions import ValidationError
+
+    from core.models import validate_timezone
+
+    # Valid timezones should not raise
+    validate_timezone("")  # blank is allowed
+    validate_timezone("America/New_York")
+    validate_timezone("Europe/London")
+    validate_timezone("Asia/Tokyo")
+    validate_timezone("UTC")
+
+    # Invalid timezones should raise ValidationError
+    with pytest.raises(ValidationError):
+        validate_timezone("Invalid/Timezone")
+    with pytest.raises(ValidationError):
+        validate_timezone("Not_A_Timezone")
+
+
+@pytest.mark.django_db
+def test_user_profile_timezone():
+    from django.core.exceptions import ValidationError
+
+    from core.models import UserProfile
+
+    user = UserFactory.create()
+    profile = UserProfile.objects.create(user=user, timezone="America/Los_Angeles")
+    profile.full_clean()  # Should not raise
+    assert profile.timezone == "America/Los_Angeles"
+
+    # Test blank timezone is allowed
+    profile.timezone = ""
+    profile.full_clean()  # Should not raise
+
+    # Test invalid timezone raises validation error
+    profile.timezone = "Invalid/Zone"
+    with pytest.raises(ValidationError):
+        profile.full_clean()
+
+
+@pytest.mark.django_db
+def test_timezone_middleware():
+    from unittest.mock import Mock, PropertyMock
+
+    from core.middleware import TimezoneMiddleware
+    from core.models import UserProfile
+
+    # Test 1: User with valid timezone
+    user1 = UserFactory.create()
+    UserProfile.objects.create(user=user1, timezone="America/Los_Angeles")
+
+    request = Mock()
+    request.user = user1
+    type(request.user).is_authenticated = PropertyMock(return_value=True)
+
+    mock_response = Mock()
+    get_response = Mock(return_value=mock_response)
+    middleware = TimezoneMiddleware(get_response)
+
+    response = middleware(request)
+    assert response == mock_response
+    get_response.assert_called_once()
+
+    # Test 2: User with no timezone set (should use default)
+    user2 = UserFactory.create()
+    UserProfile.objects.create(user=user2, timezone="")
+
+    request2 = Mock()
+    request2.user = user2
+    type(request2.user).is_authenticated = PropertyMock(return_value=True)
+
+    get_response2 = Mock(return_value=mock_response)
+    middleware2 = TimezoneMiddleware(get_response2)
+
+    response2 = middleware2(request2)
+    assert response2 == mock_response
+    get_response2.assert_called_once()
+
+    # Test 3: Unauthenticated user
+    request3 = Mock()
+    request3.user = Mock()
+    type(request3.user).is_authenticated = PropertyMock(return_value=False)
+
+    get_response3 = Mock(return_value=mock_response)
+    middleware3 = TimezoneMiddleware(get_response3)
+
+    response3 = middleware3(request3)
+    assert response3 == mock_response
+    get_response3.assert_called_once()
+
+
+@pytest.mark.django_db
+def test_timezone_in_profile_form(otis):
+    from core.models import UserProfile
+
+    user = UserFactory.create()
+    otis.login(user)
+
+    # Get the profile preferences page
+    response = otis.get("profile")
+
+    # Verify timezone field is in the form
+    content = response.content.decode()
+    assert "timezone" in content.lower() or "time zone" in content.lower()
+    assert "id_timezone" in content
+
+    # Verify we can set and save timezone directly on model
+    profile, _ = UserProfile.objects.get_or_create(user=user)
+    profile.timezone = "Europe/Paris"
+    profile.save()
+
+    profile.refresh_from_db()
+    assert profile.timezone == "Europe/Paris"
diff --git a/dashboard/templates/dashboard/pset_queue_list.html b/dashboard/templates/dashboard/pset_queue_list.html
index 6145147b1..522abfc3a 100644
--- a/dashboard/templates/dashboard/pset_queue_list.html
+++ b/dashboard/templates/dashboard/pset_queue_list.html
@@ -11,7 +11,7 @@
       <tr>
         <th class="text-end">#</th>
         <th>Unit</th>
-        <th>Timestamp (UTC)</th>
+        <th>Timestamp</th>
         <th class="text-end">PK</th>
       </tr>
     </thead>
@@ -30,7 +30,7 @@
               {% endif %}
             {% endif %}
           </td>
-          <td>{{ pset.upload.created_at|timezone:"UTC"|date:"Y-m-d H:i" }}</td>
+          <td>{{ pset.upload.created_at|date:"Y-m-d H:i" }}</td>
           <td class="text-end">
             {% if request.user.is_staff %}
               <a href="{% url "admin:dashboard_pset_change" pset.pk %}">{{ pset.pk }}</a>

From 646c8b971cc17cb2e5a380408a064ddfeda8f694 Mon Sep 17 00:00:00 2001
From: Dean Menezes <dmm3297@my.utexas.edu>
Date: Sun, 1 Mar 2026 16:08:30 -0600
Subject: [PATCH 06/14] fix: apply ruff formatting to migration file

---
 .../0065_alter_userprofile_timezone.py        | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/core/migrations/0065_alter_userprofile_timezone.py b/core/migrations/0065_alter_userprofile_timezone.py
index 65a26e503..ea04c91fb 100644
--- a/core/migrations/0065_alter_userprofile_timezone.py
+++ b/core/migrations/0065_alter_userprofile_timezone.py
@@ -1,19 +1,26 @@
 # Generated by Django 5.2.11 on 2026-03-01 22:05
 
-import core.models
 from django.db import migrations, models
 
+import core.models
+
 
 class Migration(migrations.Migration):
-
     dependencies = [
-        ('core', '0064_userprofile_timezone'),
+        ("core", "0064_userprofile_timezone"),
     ]
 
     operations = [
         migrations.AlterField(
-            model_name='userprofile',
-            name='timezone',
-            field=models.CharField(blank=True, default='', help_text='Your local time zone for displaying timestamps. Leave blank to use server time (America/New_York).', max_length=63, validators=[core.models.validate_timezone], verbose_name='Time zone'),
+            model_name="userprofile",
+            name="timezone",
+            field=models.CharField(
+                blank=True,
+                default="",
+                help_text="Your local time zone for displaying timestamps. Leave blank to use server time (America/New_York).",
+                max_length=63,
+                validators=[core.models.validate_timezone],
+                verbose_name="Time zone",
+            ),
         ),
     ]

From 2dfc93218020777d769430b729588876d96c998c Mon Sep 17 00:00:00 2001
From: Dean Menezes <dmm3297@my.utexas.edu>
Date: Thu, 5 Mar 2026 17:14:49 -0600
Subject: [PATCH 07/14] fix: avoid timezone middleware writes and improve
 timezone picker

---
 core/middleware.py                        |  4 ++--
 core/templates/core/userprofile_form.html | 11 ++++++++++-
 core/views.py                             | 16 ++++++++++++++++
 3 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/core/middleware.py b/core/middleware.py
index 55b13f1b8..47ed27a3c 100644
--- a/core/middleware.py
+++ b/core/middleware.py
@@ -34,8 +34,8 @@ def __init__(self, get_response: Callable[[HttpRequest], HttpResponse]):
 
     def __call__(self, request: HttpRequest):
         if request.user.is_authenticated:
-            up, _ = UserProfile.objects.get_or_create(user=request.user)
-            if up.timezone:
+            up = UserProfile.objects.filter(user=request.user).only("timezone").first()
+            if up and up.timezone:
                 try:
                     timezone.activate(zoneinfo.ZoneInfo(up.timezone))
                 except zoneinfo.ZoneInfoNotFoundError:
diff --git a/core/templates/core/userprofile_form.html b/core/templates/core/userprofile_form.html
index 1a6f4dc08..b5855d85f 100644
--- a/core/templates/core/userprofile_form.html
+++ b/core/templates/core/userprofile_form.html
@@ -33,6 +33,9 @@ <h1>Display settings</h1>
       <h1>Advanced settings</h1>
       {% for field in advanced_fields %}{{ field|as_crispy_field }}{% endfor %}
       <button type="submit" class="btn btn-success">Update settings</button>
+      <datalist id="timezone-list">
+        {% for tz in timezone_choices %}<option value="{{ tz }}"></option>{% endfor %}
+      </datalist>
       <div id="timezone-suggestion"
            class="alert alert-info mt-2"
            style="display: none">
@@ -53,11 +56,17 @@ <h1>Advanced settings</h1>
       // Show timezone suggestion if field is empty
       document.addEventListener('DOMContentLoaded', function() {
           const timezoneField = document.getElementById('id_timezone');
+          const timezoneList = document.getElementById('timezone-list');
           const suggestionDiv = document.getElementById('timezone-suggestion');
           const detectedTzSpan = document.getElementById('detected-tz');
           const useButton = document.getElementById('use-detected-tz');
           const dismissButton = document.getElementById('dismiss-tz-suggestion');
 
+          if (timezoneField && timezoneList) {
+              timezoneField.setAttribute('list', 'timezone-list');
+              timezoneField.setAttribute('autocomplete', 'off');
+          }
+
           if (timezoneField && !timezoneField.value && suggestionDiv) {
               try {
                   const detectedTimezone = Intl.DateTimeFormat().resolvedOptions().timeZone;
@@ -75,7 +84,7 @@ <h1>Advanced settings</h1>
                       });
                   }
               } catch (error) {
-                  console.log('Could not auto-detect timezone:', error);
+                  // Fail silently if auto-detection isn't available.
               }
           }
       });
diff --git a/core/views.py b/core/views.py
index 86441eb89..abaa5fefa 100644
--- a/core/views.py
+++ b/core/views.py
@@ -1,3 +1,4 @@
+import zoneinfo
 from typing import Any, Optional
 
 from braces.views import LoginRequiredMixin
@@ -39,6 +40,20 @@
 
 # Create your views here.
 
+PREFERRED_TIMEZONES = (
+    "America/New_York",
+    "America/Chicago",
+    "America/Denver",
+    "America/Los_Angeles",
+    "America/Phoenix",
+    "America/Anchorage",
+    "Pacific/Honolulu",
+)
+_all_timezones = set(zoneinfo.available_timezones())
+_preferred_timezones = [tz for tz in PREFERRED_TIMEZONES if tz in _all_timezones]
+_remaining_timezones = sorted(_all_timezones - set(_preferred_timezones))
+TIMEZONE_CHOICES = [*_preferred_timezones, *_remaining_timezones]
+
 
 class AdminUnitListView(AdminRequiredMixin, ListView[Unit]):
     model = Unit
@@ -336,6 +351,7 @@ def get_context_data(self, **kwargs):
             form["timezone"],
             form["use_twemoji"],
         )
+        context["timezone_choices"] = TIMEZONE_CHOICES
 
         return context
 

From f99b3e479c708c0e28ff7a9a963281319f477caf Mon Sep 17 00:00:00 2001
From: Dean Menezes <dmm3297@my.utexas.edu>
Date: Thu, 5 Mar 2026 17:19:15 -0600
Subject: [PATCH 08/14] chore: merge timezone and disable_hints migrations

---
 core/migrations/0066_merge_20260305_1818.py | 14 ++++++++++++++
 1 file changed, 14 insertions(+)
 create mode 100644 core/migrations/0066_merge_20260305_1818.py

diff --git a/core/migrations/0066_merge_20260305_1818.py b/core/migrations/0066_merge_20260305_1818.py
new file mode 100644
index 000000000..596885c04
--- /dev/null
+++ b/core/migrations/0066_merge_20260305_1818.py
@@ -0,0 +1,14 @@
+# Generated by Django 5.2.12 on 2026-03-05 23:18
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0064_userprofile_disable_hints'),
+        ('core', '0065_alter_userprofile_timezone'),
+    ]
+
+    operations = [
+    ]

From cd691301941ecc9a6182edf2d958486b917f6742 Mon Sep 17 00:00:00 2001
From: Dean Menezes <dmm3297@my.utexas.edu>
Date: Thu, 5 Mar 2026 17:25:51 -0600
Subject: [PATCH 09/14] test: cover timezone middleware and view context

---
 core/tests.py | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/core/tests.py b/core/tests.py
index ec6aca939..e9635d286 100644
--- a/core/tests.py
+++ b/core/tests.py
@@ -546,6 +546,26 @@ def test_timezone_middleware():
     get_response3.assert_called_once()
 
 
+@pytest.mark.django_db
+def test_timezone_middleware_does_not_create_profile():
+    from django.http import HttpResponse
+    from django.test import RequestFactory
+
+    from core.middleware import TimezoneMiddleware
+    from core.models import UserProfile
+
+    user = UserFactory.create()
+    assert not UserProfile.objects.filter(user=user).exists()
+
+    request = RequestFactory().get("/")
+    request.user = user
+
+    middleware = TimezoneMiddleware(lambda _: HttpResponse("ok"))
+    middleware(request)
+
+    assert not UserProfile.objects.filter(user=user).exists()
+
+
 @pytest.mark.django_db
 def test_timezone_in_profile_form(otis):
     from core.models import UserProfile
@@ -568,3 +588,23 @@ def test_timezone_in_profile_form(otis):
 
     profile.refresh_from_db()
     assert profile.timezone == "Europe/Paris"
+
+
+@pytest.mark.django_db
+def test_profile_timezone_choices_order(otis):
+    user = UserFactory.create()
+    otis.login(user)
+
+    response = otis.get_20x("profile")
+    timezone_choices = response.context["timezone_choices"]
+
+    assert timezone_choices[:7] == [
+        "America/New_York",
+        "America/Chicago",
+        "America/Denver",
+        "America/Los_Angeles",
+        "America/Phoenix",
+        "America/Anchorage",
+        "Pacific/Honolulu",
+    ]
+    assert "Europe/London" in timezone_choices

From 131aa80764951bedbd293f313650ff4de6937c91 Mon Sep 17 00:00:00 2001
From: Dean Menezes <dmm3297@my.utexas.edu>
Date: Thu, 5 Mar 2026 17:26:47 -0600
Subject: [PATCH 10/14] chore: format merge migration

---
 core/migrations/0066_merge_20260305_1818.py | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/core/migrations/0066_merge_20260305_1818.py b/core/migrations/0066_merge_20260305_1818.py
index 596885c04..2da7cce7a 100644
--- a/core/migrations/0066_merge_20260305_1818.py
+++ b/core/migrations/0066_merge_20260305_1818.py
@@ -4,11 +4,9 @@
 
 
 class Migration(migrations.Migration):
-
     dependencies = [
-        ('core', '0064_userprofile_disable_hints'),
-        ('core', '0065_alter_userprofile_timezone'),
+        ("core", "0064_userprofile_disable_hints"),
+        ("core", "0065_alter_userprofile_timezone"),
     ]
 
-    operations = [
-    ]
+    operations = []

From e6038f22a875991e226375c4ca42dcf83dd46e03 Mon Sep 17 00:00:00 2001
From: Evan Chen <evan@evanchen.cc>
Date: Thu, 5 Mar 2026 18:37:39 -0500
Subject: [PATCH 11/14] refactor: clean up migration files

---
 core/migrations/0064_userprofile_timezone.py  | 23 -------------------
 ...mezone.py => 0065_userprofile_timezone.py} |  6 ++---
 core/migrations/0066_merge_20260305_1818.py   | 12 ----------
 3 files changed, 3 insertions(+), 38 deletions(-)
 delete mode 100644 core/migrations/0064_userprofile_timezone.py
 rename core/migrations/{0065_alter_userprofile_timezone.py => 0065_userprofile_timezone.py} (82%)
 delete mode 100644 core/migrations/0066_merge_20260305_1818.py

diff --git a/core/migrations/0064_userprofile_timezone.py b/core/migrations/0064_userprofile_timezone.py
deleted file mode 100644
index 6cc92a4c9..000000000
--- a/core/migrations/0064_userprofile_timezone.py
+++ /dev/null
@@ -1,23 +0,0 @@
-# Generated by Django 5.2.11 on 2026-03-01 21:24
-
-from django.db import migrations, models
-
-
-class Migration(migrations.Migration):
-    dependencies = [
-        ("core", "0063_alter_userprofile_dynamic_progress_and_more"),
-    ]
-
-    operations = [
-        migrations.AddField(
-            model_name="userprofile",
-            name="timezone",
-            field=models.CharField(
-                blank=True,
-                default="",
-                help_text="Your local time zone for displaying timestamps. Leave blank to use server time (America/New_York).",
-                max_length=63,
-                verbose_name="Time zone",
-            ),
-        ),
-    ]
diff --git a/core/migrations/0065_alter_userprofile_timezone.py b/core/migrations/0065_userprofile_timezone.py
similarity index 82%
rename from core/migrations/0065_alter_userprofile_timezone.py
rename to core/migrations/0065_userprofile_timezone.py
index ea04c91fb..39c22f1aa 100644
--- a/core/migrations/0065_alter_userprofile_timezone.py
+++ b/core/migrations/0065_userprofile_timezone.py
@@ -1,4 +1,4 @@
-# Generated by Django 5.2.11 on 2026-03-01 22:05
+# Generated by Django 5.2.12 on 2026-03-05 23:37
 
 from django.db import migrations, models
 
@@ -7,11 +7,11 @@
 
 class Migration(migrations.Migration):
     dependencies = [
-        ("core", "0064_userprofile_timezone"),
+        ("core", "0064_userprofile_disable_hints"),
     ]
 
     operations = [
-        migrations.AlterField(
+        migrations.AddField(
             model_name="userprofile",
             name="timezone",
             field=models.CharField(
diff --git a/core/migrations/0066_merge_20260305_1818.py b/core/migrations/0066_merge_20260305_1818.py
deleted file mode 100644
index 2da7cce7a..000000000
--- a/core/migrations/0066_merge_20260305_1818.py
+++ /dev/null
@@ -1,12 +0,0 @@
-# Generated by Django 5.2.12 on 2026-03-05 23:18
-
-from django.db import migrations
-
-
-class Migration(migrations.Migration):
-    dependencies = [
-        ("core", "0064_userprofile_disable_hints"),
-        ("core", "0065_alter_userprofile_timezone"),
-    ]
-
-    operations = []

From 24f509ff3c468bd077311ea05534ad6c7dc32e6f Mon Sep 17 00:00:00 2001
From: Evan Chen <evan@evanchen.cc>
Date: Thu, 5 Mar 2026 18:43:31 -0500
Subject: [PATCH 12/14] polish: some presentation changes

---
 core/views.py | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/core/views.py b/core/views.py
index abaa5fefa..46278e36a 100644
--- a/core/views.py
+++ b/core/views.py
@@ -41,13 +41,13 @@
 # Create your views here.
 
 PREFERRED_TIMEZONES = (
-    "America/New_York",
-    "America/Chicago",
-    "America/Denver",
+    "Pacific/Honolulu",
+    "America/Anchorage",
     "America/Los_Angeles",
     "America/Phoenix",
-    "America/Anchorage",
-    "Pacific/Honolulu",
+    "America/Denver",
+    "America/Chicago",
+    "America/New_York",
 )
 _all_timezones = set(zoneinfo.available_timezones())
 _preferred_timezones = [tz for tz in PREFERRED_TIMEZONES if tz in _all_timezones]
@@ -348,8 +348,8 @@ def get_context_data(self, **kwargs):
             form["show_portal_instructions"],
             form["show_unit_petitions"],
             form["disable_hints"],
-            form["timezone"],
             form["use_twemoji"],
+            form["timezone"],
         )
         context["timezone_choices"] = TIMEZONE_CHOICES
 

From 7938d977acde5dcd73ef23eca104968e6b7616a5 Mon Sep 17 00:00:00 2001
From: Evan Chen <evan@evanchen.cc>
Date: Thu, 5 Mar 2026 18:46:25 -0500
Subject: [PATCH 13/14] tests: match PREFERRED_TIMEZONES

---
 core/tests.py | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/core/tests.py b/core/tests.py
index e9635d286..5f7afb27f 100644
--- a/core/tests.py
+++ b/core/tests.py
@@ -599,12 +599,12 @@ def test_profile_timezone_choices_order(otis):
     timezone_choices = response.context["timezone_choices"]
 
     assert timezone_choices[:7] == [
-        "America/New_York",
-        "America/Chicago",
-        "America/Denver",
+        "Pacific/Honolulu",
+        "America/Anchorage",
         "America/Los_Angeles",
         "America/Phoenix",
-        "America/Anchorage",
-        "Pacific/Honolulu",
+        "America/Denver",
+        "America/Chicago",
+        "America/New_York",
     ]
     assert "Europe/London" in timezone_choices

From 3716127fd071101ac93977ed9f8320cfdd89e813 Mon Sep 17 00:00:00 2001
From: Dean Menezes <dmm3297@my.utexas.edu>
Date: Thu, 5 Mar 2026 18:09:49 -0600
Subject: [PATCH 14/14] Improve timezone picker search and add alias coverage
 tests

---
 core/templates/core/userprofile_form.html | 78 +++++++++++++++++++++--
 core/tests.py                             | 20 ++++++
 core/views.py                             | 18 +++++-
 3 files changed, 108 insertions(+), 8 deletions(-)

diff --git a/core/templates/core/userprofile_form.html b/core/templates/core/userprofile_form.html
index b5855d85f..5b467b79a 100644
--- a/core/templates/core/userprofile_form.html
+++ b/core/templates/core/userprofile_form.html
@@ -32,10 +32,15 @@ <h1>Display settings</h1>
     <div class="section">
       <h1>Advanced settings</h1>
       {% for field in advanced_fields %}{{ field|as_crispy_field }}{% endfor %}
+      <div class="mb-2">
+        <label for="timezone-search" class="form-label">Search time zone</label>
+        <input type="text"
+               class="form-control"
+               id="timezone-search"
+               placeholder="Type to filter, e.g. Seoul or Korea" />
+      </div>
+      {{ timezone_field|as_crispy_field }}
       <button type="submit" class="btn btn-success">Update settings</button>
-      <datalist id="timezone-list">
-        {% for tz in timezone_choices %}<option value="{{ tz }}"></option>{% endfor %}
-      </datalist>
       <div id="timezone-suggestion"
            class="alert alert-info mt-2"
            style="display: none">
@@ -49,6 +54,7 @@ <h1>Advanced settings</h1>
                 id="dismiss-tz-suggestion"></button>
       </div>
     </div>
+    {{ timezone_extra_aliases|json_script:"timezone-extra-aliases" }}
   </form>
 {% endblock layout-content %}
 {% block scripts %}
@@ -56,15 +62,73 @@ <h1>Advanced settings</h1>
       // Show timezone suggestion if field is empty
       document.addEventListener('DOMContentLoaded', function() {
           const timezoneField = document.getElementById('id_timezone');
-          const timezoneList = document.getElementById('timezone-list');
+          const timezoneSearch = document.getElementById('timezone-search');
           const suggestionDiv = document.getElementById('timezone-suggestion');
           const detectedTzSpan = document.getElementById('detected-tz');
           const useButton = document.getElementById('use-detected-tz');
           const dismissButton = document.getElementById('dismiss-tz-suggestion');
+          const aliasesScript = document.getElementById('timezone-extra-aliases');
+          let aliasesByTimezone = {};
+          if (aliasesScript) {
+              aliasesByTimezone = JSON.parse(aliasesScript.textContent);
+          }
 
-          if (timezoneField && timezoneList) {
-              timezoneField.setAttribute('list', 'timezone-list');
-              timezoneField.setAttribute('autocomplete', 'off');
+          function getTimezoneNameForSearch(timezoneName) {
+              if (!timezoneName) {
+                  return '';
+              }
+              try {
+                  const parts = new Intl.DateTimeFormat('en-US', {
+                      timeZone: timezoneName,
+                      timeZoneName: 'longGeneric',
+                  }).formatToParts(new Date());
+                  const zonePart = parts.find(function(part) {
+                      return part.type === 'timeZoneName';
+                  });
+                  return zonePart ? zonePart.value : '';
+              } catch (error) {
+                  return '';
+              }
+          }
+
+          let allOptions = [];
+          if (timezoneField) {
+              allOptions = Array.from(timezoneField.options).map(function(opt) {
+                  const aliasText = (aliasesByTimezone[opt.value] || []).join(' ');
+                  const zoneNameText = getTimezoneNameForSearch(opt.value);
+                  return {
+                      value: opt.value,
+                      label: opt.textContent,
+                      searchText: (opt.textContent + ' ' + zoneNameText + ' ' + aliasText).toLowerCase()
+                  };
+              });
+          }
+
+          if (timezoneSearch && timezoneField) {
+              timezoneSearch.addEventListener('input', function() {
+                  const query = timezoneSearch.value.toLowerCase().trim();
+                  const selectedValue = timezoneField.value;
+                  const filtered = allOptions.filter(function(opt) {
+                      if (!query) {
+                          return true;
+                      }
+                      return opt.searchText.includes(query);
+                  });
+                  timezoneField.innerHTML = '';
+                  filtered.forEach(function(opt) {
+                      const option = document.createElement('option');
+                      option.value = opt.value;
+                      option.textContent = opt.label;
+                      timezoneField.appendChild(option);
+                  });
+                  if (filtered.some(function(opt) {
+                          return opt.value === selectedValue;
+                      })) {
+                      timezoneField.value = selectedValue;
+                  } else if (filtered.length > 0) {
+                      timezoneField.selectedIndex = 0;
+                  }
+              });
           }
 
           if (timezoneField && !timezoneField.value && suggestionDiv) {
diff --git a/core/tests.py b/core/tests.py
index 5f7afb27f..48ebf139e 100644
--- a/core/tests.py
+++ b/core/tests.py
@@ -580,6 +580,8 @@ def test_timezone_in_profile_form(otis):
     content = response.content.decode()
     assert "timezone" in content.lower() or "time zone" in content.lower()
     assert "id_timezone" in content
+    assert '<select name="timezone"' in content
+    assert "Asia/Seoul" in content
 
     # Verify we can set and save timezone directly on model
     profile, _ = UserProfile.objects.get_or_create(user=user)
@@ -608,3 +610,21 @@ def test_profile_timezone_choices_order(otis):
         "America/New_York",
     ]
     assert "Europe/London" in timezone_choices
+
+
+@pytest.mark.django_db
+def test_profile_timezone_search_aliases(otis):
+    user = UserFactory.create()
+    otis.login(user)
+
+    response = otis.get_20x("profile")
+    extra_aliases = response.context["timezone_extra_aliases"]
+    content = response.content.decode()
+
+    assert "timeZoneName: 'longGeneric'" in content
+    assert "Asia/Seoul" in content
+    assert "Europe/Vienna" in content
+    if "Asia/Kolkata" in response.context["timezone_choices"]:
+        assert "bombay" in extra_aliases["Asia/Kolkata"]
+    elif "Asia/Calcutta" in response.context["timezone_choices"]:
+        assert "bombay" in extra_aliases["Asia/Calcutta"]
diff --git a/core/views.py b/core/views.py
index 46278e36a..526e202dc 100644
--- a/core/views.py
+++ b/core/views.py
@@ -12,6 +12,7 @@
 from django.db.models.expressions import Value
 from django.db.models.query import QuerySet
 from django.db.models.query_utils import Q
+from django.forms import Select
 from django.forms.models import BaseModelForm
 from django.http import Http404, HttpRequest, HttpResponse, HttpResponseRedirect
 from django.http.response import JsonResponse
@@ -53,6 +54,15 @@
 _preferred_timezones = [tz for tz in PREFERRED_TIMEZONES if tz in _all_timezones]
 _remaining_timezones = sorted(_all_timezones - set(_preferred_timezones))
 TIMEZONE_CHOICES = [*_preferred_timezones, *_remaining_timezones]
+TIMEZONE_SELECT_CHOICES = [
+    ("", "Server default (America/New_York)"),
+    *((tz, tz) for tz in TIMEZONE_CHOICES),
+]
+TIMEZONE_EXTRA_ALIASES: dict[str, tuple[str, ...]] = {
+    # Common legacy city names users may still search for.
+    "Asia/Kolkata": ("bombay",),
+    "Asia/Calcutta": ("bombay",),
+}
 
 
 class AdminUnitListView(AdminRequiredMixin, ListView[Unit]):
@@ -349,12 +359,18 @@ def get_context_data(self, **kwargs):
             form["show_unit_petitions"],
             form["disable_hints"],
             form["use_twemoji"],
-            form["timezone"],
         )
+        context["timezone_field"] = form["timezone"]
         context["timezone_choices"] = TIMEZONE_CHOICES
+        context["timezone_extra_aliases"] = TIMEZONE_EXTRA_ALIASES
 
         return context
 
+    def get_form(self, form_class=None):
+        form = super().get_form(form_class)
+        form.fields["timezone"].widget = Select(choices=TIMEZONE_SELECT_CHOICES)
+        return form
+
 
 @login_required
 def dismiss(request: AuthHttpRequest) -> JsonResponse: