Handle prices with UTC timestamps in the raw data for non-FI regions

Author: slovdahl

spothinta_api/models.py

@@ -257,16 +257,26 @@ def prices_today(self) -> dict[datetime, float]:
             The prices for today.
 
         """
-        today = self.now_in_timezone().astimezone().date()
+        today = self.now_in_timezone().date()
         prices = {
             timestamp: price
             for timestamp, price in self.prices.items()
-            if timestamp.date() == today
+            if timestamp.astimezone(self.time_zone).date() == today
         }
 
-        if (self.resolution == timedelta(minutes=15) and len(prices) == 96) or (
-            self.resolution == timedelta(minutes=60) and len(prices) == 24
-        ):
+        # Use midnight-to-midnight span to avoid off-by-one from 23:59:59.999999.
+        day_start = datetime.combine(today, datetime.min.time(), tzinfo=self.time_zone)
+        next_day_start = datetime.combine(
+            today + timedelta(days=1),
+            datetime.min.time(),
+            tzinfo=self.time_zone,
+        )
+        expected_intervals = max(
+            1,
+            int((next_day_start - day_start) / self.resolution),
+        )
+
+        if len(prices) == expected_intervals:
             return prices
 
         return {}
@@ -279,16 +289,30 @@ def prices_tomorrow(self) -> dict[datetime, float]:
             The prices for tomorrow.
 
         """
-        tomorrow = (self.now_in_timezone() + timedelta(days=1)).astimezone().date()
+        tomorrow = (self.now_in_timezone() + timedelta(days=1)).date()
         prices = {
             timestamp: price
             for timestamp, price in self.prices.items()
-            if timestamp.date() == tomorrow
+            if timestamp.astimezone(self.time_zone).date() == tomorrow
         }
 
-        if (self.resolution == timedelta(minutes=15) and len(prices) == 96) or (
-            self.resolution == timedelta(minutes=60) and len(prices) == 24
-        ):
+        # Use midnight-to-midnight span to avoid off-by-one from 23:59:59.999999.
+        day_start = datetime.combine(
+            tomorrow,
+            datetime.min.time(),
+            tzinfo=self.time_zone,
+        )
+        next_day_start = datetime.combine(
+            tomorrow + timedelta(days=1),
+            datetime.min.time(),
+            tzinfo=self.time_zone,
+        )
+        expected_intervals = max(
+            1,
+            int((next_day_start - day_start) / self.resolution),
+        )
+
+        if len(prices) == expected_intervals:
             return prices
 
         return {}

tests/test_models.py

@@ -1,6 +1,7 @@
 """Test the models."""
 
 from datetime import datetime, timedelta, timezone
+from zoneinfo import ZoneInfo
 
 import pytest
 from aiohttp import ClientSession
@@ -140,10 +141,10 @@ async def test_model_se1_15_minute_resolution(aresponses: ResponsesMockServer) -
         assert energy.highest_price_tomorrow == 0.0059
         assert energy.lowest_price_today == 0.00001
         assert energy.lowest_price_tomorrow == 0.00005
-        assert energy.average_price_today == 0.00113
-        assert energy.average_price_tomorrow == 0.00249
+        assert energy.average_price_today == 0.00121
+        assert energy.average_price_tomorrow == 0.00232
         assert energy.current_price == 0.00128
-        assert energy.intervals_priced_equal_or_lower == 57
+        assert energy.intervals_priced_equal_or_lower == 51
         # The price for another interval
         another_interval = datetime(2025, 10, 4, 18, 0, tzinfo=timezone.utc)
         assert energy.price_at_time(another_interval) == 0.00242
@@ -166,6 +167,26 @@ async def test_model_se1_15_minute_resolution(aresponses: ResponsesMockServer) -
         assert isinstance(energy.timestamp_prices, list)
 
 
+@pytest.mark.freeze_time("2025-10-04 16:00:00+02:00")
+async def test_prices_today_uses_region_local_date_for_utc_timestamps() -> None:
+    """Use local date boundaries for SE1 even when source timestamps are UTC."""
+    start_utc = datetime(2025, 10, 3, 22, 0, tzinfo=timezone.utc)
+    prices = {start_utc + i * timedelta(minutes=15): i / 100000 for i in range(96)}
+    energy = Electricity(
+        prices=prices,
+        resolution=timedelta(minutes=15),
+        time_zone=ZoneInfo("Europe/Stockholm"),
+    )
+
+    prices_today = energy.prices_today()
+    assert len(prices_today) == 96
+    assert energy.current_price == 0.00064
+    assert energy.lowest_price_today == 0.0
+    assert energy.highest_price_today == 0.00095
+    assert energy.average_price_today == 0.00047
+    assert energy.prices_tomorrow() == {}
+
+
 @pytest.mark.freeze_time("2023-05-06 15:00:00+03:00")
 async def test_model_no_prices_for_tomorrow(aresponses: ResponsesMockServer) -> None:
     """Test the model for usage at 15:00:00 UTC+3 with no prices for tomorrow."""