[books] Allow timezone changes when importing from KOReader

Turns out you need a city-based timezone for DST stuff to work properly.
The US/Eastern timezone doesn't mess with DST because it can be so wonky
in different regions. So while we fix timezone defaulting to a
DST-friendly timezone too.

vrobbler/apps/books/koreader.py

@@ -4,7 +4,8 @@ import sqlite3
 from datetime import datetime, timedelta
 from enum import Enum
 
-import pytz
+import pendulum
+from zoneinfo import ZoneInfo
 import requests
 from books.constants import BOOKS_TITLES_TO_IGNORE
 from django.apps import apps
@@ -208,6 +209,35 @@ def build_page_data(page_rows: list, book_map: dict, user_tz=None) -> dict:
         )
     return book_map
 
+def one_off_fix_colins_profile(profile):
+    home_tz = "America/New_York"
+
+    europe = "2023-10-15"
+    europe_tz = "Europe/Paris"
+    europe_end = "2023-12-15"
+
+    washington = "2023-10-15"
+    washington_tz = "America/Los_Angeles"
+    washington_end = "2023-05-04"
+
+    camp = "2024-08-04"
+    camp_end = "2024-08-10"
+    camp_tz = "America/Halifax"
+
+    summer = "2025-07-10"
+    summer_end = "2025-07-13"
+    summer_tz = "America/Los_Angeles"
+
+    profile.timezone_change_log = ""
+    profile.timezone_change_log += f"{europe_tz} - {pendulum.parse(europe)}\n"
+    profile.timezone_change_log += f"{home_tz} - {pendulum.parse(europe_end)}\n"
+    profile.timezone_change_log += f"{washington_tz} - {pendulum.parse(washington)}\n"
+    profile.timezone_change_log += f"{home_tz} - {pendulum.parse(washington_end)}\n"
+    profile.timezone_change_log += f"{camp_tz} - {pendulum.parse(camp)}\n"
+    profile.timezone_change_log += f"{home_tz} - {pendulum.parse(camp_end)}\n"
+    profile.timezone_change_log += f"{summer_tz} - {pendulum.parse(summer)}\n"
+    profile.timezone_change_log += f"{home_tz} - {pendulum.parse(summer_end)}\n"
+    profile.save()
 
 def build_scrobbles_from_book_map(
     book_map: dict, user: "User"
@@ -278,55 +308,18 @@ def build_scrobbles_from_book_map(
                     )
                     continue
 
-                timezone = user.profile.timezone
-
-                timestamp = datetime.fromtimestamp(
-                    int(first_page.get("start_ts"))
-                ).replace(tzinfo=pytz.timezone(timezone))
-
-                # Add a shim here temporarily to fix imports while we were in France
-                # if date is between 10/15 and 12/15, cast it to Europe/Central
-                if (
-                    datetime(2023, 10, 15).replace(
-                        tzinfo=pytz.timezone("Europe/Paris")
-                    )
-                    <= timestamp
-                    <= datetime(2023, 12, 15).replace(
-                        tzinfo=pytz.timezone("Europe/Paris")
-                    )
-                ):
-                    timezone = "Europe/Paris"
-                if (
-                    datetime(2024, 4, 28).replace(
-                        tzinfo=pytz.timezone("US/Pacific")
-                    )
-                    <= timestamp
-                    <= datetime(2024, 5, 4).replace(
-                        tzinfo=pytz.timezone("US/Pacific")
-                    )
-                ):
-                    timezone = "US/Pacific"
-                if (
-                    datetime(2024, 8, 4).replace(
-                        tzinfo=pytz.timezone("Canada/Atlantic")
-                    )
-                    <= timestamp
-                    <= datetime(2024, 8, 10).replace(
-                        tzinfo=pytz.timezone("Canada/Atlantic")
-                    )
-                ):
-                    timezone = "Canada/Atlantic"
+                timestamp = user.profile.get_timestamp_with_tz(datetime.fromtimestamp(int(first_page.get("start_ts"))))
+                stop_timestamp = user.profile.get_timestamp_with_tz(datetime.fromtimestamp(int(last_page.get("end_ts"))))
 
-                stop_timestamp = datetime.fromtimestamp(
-                    int(last_page.get("end_ts"))
-                ).replace(tzinfo=pytz.timezone(timezone))
+                if user.id == 1 and not user.profile.timezone_change_log:
+                    one_off_fix_colins_profile(user.profile)
 
-                if (
-                    timestamp.tzinfo._dst.seconds == 0
-                    or stop_timestamp.tzinfo._dst.seconds == 0
-                ):
+                # Adjust for Daylight Saving Time
+                if timestamp.dst() == timedelta(0) or stop_timestamp.dst() == timedelta(0):
                     timestamp = timestamp - timedelta(hours=1)
                     stop_timestamp = stop_timestamp - timedelta(hours=1)
+                else:
+                    print("In DST! ", timestamp)
 
                 scrobble = Scrobble.objects.filter(
                     timestamp=timestamp,
@@ -356,7 +349,7 @@ def build_scrobbles_from_book_map(
                             in_progress=False,
                             played_to_completion=True,
                             long_play_complete=False,
-                            timezone=timezone,
+                            timezone=timestamp.tzinfo.name
                         )
                     )
                 # Then start over
@@ -398,9 +391,9 @@ def process_koreader_sqlite_file(file_path, user_id) -> list:
 
     new_scrobbles = []
     user = User.objects.filter(id=user_id).first()
-    tz = pytz.utc
+    tz = ZoneInfo("UTC")
     if user:
-        tz = user.profile.timezone
+        tz = user.profile.tzinfo
 
     is_os_file = "https://" not in file_path
     if is_os_file:

vrobbler/apps/profiles/migrations/0026_userprofile_timezone_change_log.py

@@ -0,0 +1,18 @@
+# Generated by Django 4.2.19 on 2025-07-11 22:24
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('profiles', '0025_rename_bgstat_id_userprofile_bgstats_id'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='userprofile',
+            name='timezone_change_log',
+            field=models.TextField(blank=True, null=True),
+        ),
+    ]

vrobbler/apps/profiles/models.py

@@ -1,4 +1,8 @@
-import pytz
+from zoneinfo import ZoneInfo
+import pendulum
+from datetime import datetime
+from django.utils import timezone
+import logging
 from django.conf import settings
 from django.contrib.auth import get_user_model
 from django.db import models
@@ -10,6 +14,7 @@ from profiles.constants import PRETTY_TIMEZONE_CHOICES
 User = get_user_model()
 BNULL = {"blank": True, "null": True}
 
+logger = logging.getLogger(__name__)
 
 class UserProfile(TimeStampedModel):
     user = models.OneToOneField(
@@ -18,6 +23,7 @@ class UserProfile(TimeStampedModel):
     timezone = models.CharField(
         max_length=255, choices=PRETTY_TIMEZONE_CHOICES, default="UTC"
     )
+    timezone_change_log = models.TextField(**BNULL)
     lastfm_username = models.CharField(max_length=255, **BNULL)
     lastfm_password = EncryptedField(**BNULL)
     lastfm_auto_import = models.BooleanField(default=False)
@@ -59,7 +65,51 @@ class UserProfile(TimeStampedModel):
 
     @property
     def tzinfo(self):
-        return pytz.timezone(self.timezone)
+        return ZoneInfo(self.timezone)
+
+    def save(self, *args, **kwargs):
+        if not self._state.adding:
+            old_instance = UserProfile.objects.get(pk=self.pk)
+            is_timezone_change = self.timezone != old_instance.timezone
+            if is_timezone_change:
+                logger.info("Updating timezone changelog for user", extra={"profile_id": self.id})
+                previous_changes = old_instance.timezone_change_log
+                now = timezone.now().replace(microsecond=0)
+                new_log = f"{self.timezone} - {now}"
+                if previous_changes:
+                    new_log = previous_changes + f"\n{new_log}"
+                self.timezone_change_log = new_log
+        super(UserProfile, self).save(*args, **kwargs)
+
+    @property
+    def historic_timezone_changes(self) -> list:
+        """Return a list of datetimes with timezones for the specific changed time"""
+        history = [pendulum.datetime(1900, 1, 1, 0, 0, 0, tz=self.tzinfo.key)]
+        if self.timezone_change_log:
+            for change in self.timezone_change_log.split("\n"):
+                if " - " in change:
+                    tz, date = change.split(" - ")
+                    history.append(pendulum.parse(date).in_timezone(tz))
+        return history
+
+    def get_timestamp_with_tz(self, timestamp):
+        timezone = self.tzinfo
+        if self.timezone_change_log:
+            change_list = self.historic_timezone_changes
+            for idx, start in enumerate(change_list):
+                try:
+                    end = change_list[idx+1]
+                except IndexError:
+                    end = None
+
+                if end:
+                    if start <= timestamp.replace(tzinfo=end.timezone) <= end:
+                        timezone = start.timezone
+                else:
+                    if start <= timestamp.replace(tzinfo=start.timezone):
+                        timezone = start.timezone
+
+        return timestamp.replace(tzinfo=timezone)
 
     @cached_property
     def task_context_tags(self) -> list[str]:

vrobbler/apps/scrobbles/admin.py

@@ -139,6 +139,7 @@ class ScrobbleAdmin(admin.ModelAdmin):
         "media_type",
         "long_play_complete",
         "source",
+        "timezone",
     )
     ordering = ("-timestamp",)
 

vrobbler/apps/scrobbles/models.py

@@ -5,7 +5,7 @@ import logging
 from collections import defaultdict
 from typing import Optional
 from uuid import uuid4
-
+from zoneinfo import ZoneInfo
 import pendulum
 import pytz
 from beers.models import Beer
@@ -750,7 +750,16 @@ class Scrobble(TimeStampedModel):
 
     @property
     def tzinfo(self):
-        return pytz.timezone(self.timezone)
+        return ZoneInfo(self.timezone)
+
+    @property
+    def local_timestamp(self):
+        return timezone.localtime(self.timestamp, timezone=self.tzinfo)
+
+    @property
+    def local_stop_timestamp(self):
+        if self.stop_tiemstamp:
+            return timezone.localtime(self.stop_timestamp, timezone=self.tzinfo)
 
     @property
     def scrobble_media_key(self) -> str:

vrobbler/settings.py

@@ -92,7 +92,7 @@ DEFAULT_TASK_CONTEXT_TAGS = [
 
 DEFAULT_AUTO_FIELD = "django.db.models.BigAutoField"
 
-TIME_ZONE = os.getenv("VROBBLER_TIME_ZONE", "US/Eastern")
+TIME_ZONE = os.getenv("VROBBLER_TIME_ZONE", "America/New_York")
 
 ALLOWED_HOSTS = ["*"]
 CSRF_TRUSTED_ORIGINS = [
@@ -111,7 +111,7 @@ CELERY_TASK_ALWAYS_EAGER = (
 )
 CELERY_BROKER_URL = REDIS_URL if REDIS_URL else "memory://localhost/"
 CELERY_RESULT_BACKEND = "django-db"
-CELERY_TIMEZONE = os.getenv("VROBBLER_TIME_ZONE", "US/Eastern")
+CELERY_TIMEZONE = os.getenv("VROBBLER_TIME_ZONE", "America/New_York")
 CELERY_TASK_TRACK_STARTED = True
 
 INSTALLED_APPS = [