From 0f10dbff8c7637652e440a0df94ff004ebdb78b1 Mon Sep 17 00:00:00 2001
From: Bohdan Horbeshko <bodqhrohro@gmail.com>
Date: Mon, 25 Aug 2025 09:27:31 -0400
Subject: [PATCH] Take flip-page into account when calculating MAM RSM
 count/index

---
 xmpp/handlers.go | 25 ++++++++++++++++++++-----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/xmpp/handlers.go b/xmpp/handlers.go
index 90aa9d6..a6560e3 100644
--- a/xmpp/handlers.go
+++ b/xmpp/handlers.go
@@ -2549,11 +2549,21 @@ func handleSetQueryMAM2(s xmpp.Sender, iq *stanza.IQ, query *extensions.MAM2Quer
 		log.Debugf("MAM: beyond")
 	} else {
 		if len(messages) > 0 {
+			firstMsgId := messages[0].Id
+			lastMsgId := messages[len(messages)-1].Id
 			if fromStart {
-				overallyFirstMessageId = messages[0].Id
+				if reverse {
+					overallyFirstMessageId = lastMsgId
+				} else {
+					overallyFirstMessageId = firstMsgId
+				}
 			}
 			if complete {
-				overallyLastMessageId = messages[len(messages)-1].Id
+				if reverse {
+					overallyLastMessageId = firstMsgId
+				} else {
+					overallyLastMessageId = lastMsgId
+				}
 			}
 		}
 
@@ -2581,17 +2591,22 @@ func handleSetQueryMAM2(s xmpp.Sender, iq *stanza.IQ, query *extensions.MAM2Quer
 		}
 
 		if len(messages) > 0 {
+			firstMsgId := messages[0].Id
+			lastMsgId := messages[len(messages)-1].Id
+			if reverse {
+				firstMsgId, lastMsgId = lastMsgId, firstMsgId
+			}
 			rs.First = &stanza.First{
-				Content: strconv.FormatInt(messages[0].Id, 10),
+				Content: strconv.FormatInt(firstMsgId, 10),
 			}
 			if firstMsgPositionCount != 0 {
-				rsmFirstMsgPosition, rsmFirstMsgPositionErr := session.GetChatMessagePosition(toID, messages[0].Id)
+				rsmFirstMsgPosition, rsmFirstMsgPositionErr := session.GetChatMessagePosition(toID, firstMsgId)
 				if rsmFirstMsgPositionErr == nil && rsmFirstMsgPosition != nil {
 					index := int(firstMsgPositionCount - rsmFirstMsgPosition.Count)
 					rs.First.Index = &index
 				}
 			}
-			last := strconv.FormatInt(messages[len(messages)-1].Id, 10)
+			last := strconv.FormatInt(lastMsgId, 10)
 			rs.Last = &last
 		}
 	}