From 9ab26976c2794cd49f26fb4a3b1b81c445c61e47 Mon Sep 17 00:00:00 2001
From: Christian Benincasa <chrisbenincasa@gmail.com>
Date: Sat, 11 Apr 2026 09:00:32 -0400
Subject: [PATCH] fix: backdate initial guide generation at startup

---
 server/src/services/TvGuideService.ts | 14 ++++++++++++--
 server/src/tasks/UpdateXmlTvTask.ts   | 15 ++++++++++++++-
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/server/src/services/TvGuideService.ts b/server/src/services/TvGuideService.ts
index 6c35af0f..a69f2271 100644
--- a/server/src/services/TvGuideService.ts
+++ b/server/src/services/TvGuideService.ts
@@ -189,7 +189,11 @@ export class TVGuideService {
     );
   }
 
-  async buildAllChannels(guideDuration: Duration, force: boolean = false) {
+  async buildAllChannels(
+    guideDuration: Duration,
+    force: boolean = false,
+    startTime: number = +dayjs(),
+  ) {
     return this.withGuideContext(async () => {
       if (isEmpty(this.channelsById)) {
         const placeholderChannel = await this.makePlaceholderChannel();
@@ -198,7 +202,13 @@ export class TVGuideService {
         delete this.cachedGuide[PlaceholderChannelId];
         await Promise.all(
           keys(this.channelsById).map((channelId) =>
-            this.buildChannelGuide(guideDuration, channelId, false, force),
+            this.buildChannelGuide(
+              guideDuration,
+              channelId,
+              false,
+              force,
+              startTime,
+            ),
           ),
         );
       }
diff --git a/server/src/tasks/UpdateXmlTvTask.ts b/server/src/tasks/UpdateXmlTvTask.ts
index 745ffcb3..15d4f43b 100644
--- a/server/src/tasks/UpdateXmlTvTask.ts
+++ b/server/src/tasks/UpdateXmlTvTask.ts
@@ -84,9 +84,22 @@ export class UpdateXmlTvTask extends Task2<typeof UpdateXmlTvTaskRequest> {
           true,
         );
       } else {
+        // Round start time down to the nearest hour so guide boundaries align
+        // with the hour-granular requests made by the UI and other consumers.
+        // Extend the duration by the fractional hour we went back so the guide
+        // end time — and therefore coverage before the next scheduled run — is
+        // identical to what it would have been without rounding.
+        const now = dayjs();
+        const startTime = now.startOf('hour');
+        const extraDuration = dayjs.duration(now.diff(startTime));
+        const guideDuration = dayjs
+          .duration({ hours: xmltvSettings.programmingHours })
+          .add(extraDuration);
+
         await this.guideService.buildAllChannels(
-          dayjs.duration({ hours: xmltvSettings.programmingHours }),
+          guideDuration,
           false,
+          startTime.valueOf(),
         );
       }