fix block playout epg time zone (#2166)

CHANGELOG.md

@@ -138,6 +138,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Fix VAAPI tonemap failure
 - Fix green bars after VAAPI tonemap
 - Fix bug where playout mode `Multiple` would ignore fixed start time
+- Fix block playout EPG generation to use XMLTV Time Zone setting
 
 ## [25.2.0] - 2025-06-24
 ### Added

ErsatzTV.Application/Channels/Commands/RefreshChannelDataHandler.cs

@@ -346,7 +346,7 @@ public class RefreshChannelDataHandler : IRequestHandler<RefreshChannelData>
         }
     }
 
-    private static async Task WriteBlockPlayoutXml(
+    private async Task WriteBlockPlayoutXml(
         RefreshChannelData request,
         List<PlayoutItem> sorted,
         XmlTemplateContext templateContext,
@@ -358,6 +358,10 @@ public class RefreshChannelDataHandler : IRequestHandler<RefreshChannelData>
         XmlMinifier minifier,
         XmlWriter xml)
     {
+        XmltvTimeZone xmltvTimeZone = await _configElementRepository
+            .GetValue<XmltvTimeZone>(ConfigElementKey.XmltvTimeZone)
+            .IfNoneAsync(XmltvTimeZone.Local);
+
         var groups = sorted.GroupBy(s => new { s.GuideStart, s.GuideFinish, s.GuideGroup });
         foreach (var group in groups)
         {
@@ -373,7 +377,12 @@ public class RefreshChannelDataHandler : IRequestHandler<RefreshChannelData>
 
             TimeSpan perItem = groupDuration / itemsToInclude.Count;
 
-            DateTimeOffset currentStart = new DateTimeOffset(groupStart, TimeSpan.Zero).ToLocalTime();
+            DateTimeOffset currentStart = xmltvTimeZone switch
+            {
+                XmltvTimeZone.Utc => new DateTimeOffset(groupStart, TimeSpan.Zero),
+                _ => new DateTimeOffset(groupStart, TimeSpan.Zero).ToLocalTime()
+            };
+
             DateTimeOffset currentFinish = currentStart + perItem;
 
             foreach (PlayoutItem item in itemsToInclude)

ErsatzTV.Core.Tests/Scheduling/MultiPartEpisodeGrouperTests.cs

@@ -57,7 +57,9 @@ public class MultiPartEpisodeGrouperTests
 
     [Test]
     [TestCase("The Meddlers (Part One)", "The Meddlers (Part Two)", "The Meddlers (Part Three)")]
-    [TestCase("S01E01 The Slaves of Jedikiah, Part 1", "S01E02 The Slaves of Jedikiah, Part 2", "S01E03 The Slaves of Jedikiah, Part 3")]
+    [TestCase("The Slaves of Jedikiah, Part 1", "The Slaves of Jedikiah, Part 2", "The Slaves of Jedikiah, Part 3")]
+    [TestCase("An Unearthly Child: An Unearthly Child (1)", "An Unearthly Child: The Cave of Skulls (2)", "An Unearthly Child: The Forest of Fear (3)")]
+    [TestCase("The Savages (1)", "The Savages (2)", "The Savages (3)")]
     public void All_Grouped(string one, string two, string three)
     {
         var mediaItems = new List<MediaItem>