From f7f6fdc7709a9aba9e2863cc5241dec0ea836af6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jorge=20Mart=C3=ADn?= <jorgem@element.io>
Date: Wed, 19 Jul 2023 13:14:45 +0200
Subject: [PATCH] Don't blindly retry fetching pending or failed event details

---
 .../matrix/api/timeline/item/event/EventContent.kt | 14 ++++++++++++++
 .../api/timeline/item/event/EventTimelineItem.kt   |  2 +-
 .../impl/timeline/item/event/EventMessageMapper.kt |  3 ++-
 3 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/timeline/item/event/EventContent.kt b/libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/timeline/item/event/EventContent.kt
index 843c232890..203fb30794 100644
--- a/libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/timeline/item/event/EventContent.kt
+++ b/libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/timeline/item/event/EventContent.kt
@@ -35,7 +35,13 @@ data class MessageContent(
 
 
 sealed interface InReplyTo {
+    /** The event details are not loaded yet. We can fetch them. */
     data class NotLoaded(val eventId: EventId) : InReplyTo
+
+    /** The event details are pending to be fetched. We should **not** fetch them again. */
+    object Pending : InReplyTo
+
+    /** The event details are available. */
     data class Ready(
         val eventId: EventId,
         val content: MessageContent,
@@ -44,6 +50,14 @@ sealed interface InReplyTo {
         val senderAvatarUrl: String?,
     ) : InReplyTo
 
+    /**
+     * Fetching the event details failed.
+     *
+     * We can try to fetch them again **with a proper retry strategy**, but not blindly:
+     *
+     * If the reason for the failure is consistent on the server, we'd enter a loop
+     * where we keep trying to fetch the same event.
+     * */
     object Error : InReplyTo
 }
 
diff --git a/libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/timeline/item/event/EventTimelineItem.kt b/libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/timeline/item/event/EventTimelineItem.kt
index ef7f4d47b0..50bf5f8ce5 100644
--- a/libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/timeline/item/event/EventTimelineItem.kt
+++ b/libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/timeline/item/event/EventTimelineItem.kt
@@ -42,6 +42,6 @@ data class EventTimelineItem(
     }
     fun hasNotLoadedInReplyTo(): Boolean {
         val details = inReplyTo()
-        return details is InReplyTo.NotLoaded || details is InReplyTo.Error
+        return details is InReplyTo.NotLoaded
     }
 }
diff --git a/libraries/matrix/impl/src/main/kotlin/io/element/android/libraries/matrix/impl/timeline/item/event/EventMessageMapper.kt b/libraries/matrix/impl/src/main/kotlin/io/element/android/libraries/matrix/impl/timeline/item/event/EventMessageMapper.kt
index 2ecad95e4f..9f4df1f6b3 100644
--- a/libraries/matrix/impl/src/main/kotlin/io/element/android/libraries/matrix/impl/timeline/item/event/EventMessageMapper.kt
+++ b/libraries/matrix/impl/src/main/kotlin/io/element/android/libraries/matrix/impl/timeline/item/event/EventMessageMapper.kt
@@ -58,7 +58,8 @@ class EventMessageMapper {
                     )
                 }
                 is RepliedToEventDetails.Error -> InReplyTo.Error
-                is RepliedToEventDetails.Pending, is RepliedToEventDetails.Unavailable -> InReplyTo.NotLoaded(inReplyToId!!)
+                is RepliedToEventDetails.Pending -> InReplyTo.Pending
+                is RepliedToEventDetails.Unavailable -> InReplyTo.NotLoaded(inReplyToId!!)
             }
         }
         MessageContent(