From fcf6ed4dd798906df1935db5370c4df37b2fe166 Mon Sep 17 00:00:00 2001
From: Djorkaeff Alexandre <djorkaeff.unb@gmail.com>
Date: Tue, 9 Jun 2020 17:09:18 -0300
Subject: [PATCH] [FIX] Load messages when hideSystemMessages is enabled
 (#2101)

* [WIP] Load messages when hideSystemMessages is enabled

* Improve method name

* Minor improvements

Co-authored-by: Diego Mello <diegolmello@gmail.com>
---
 app/views/RoomView/List.js | 32 ++++++++++++++++++++++++++++----
 1 file changed, 28 insertions(+), 4 deletions(-)

diff --git a/app/views/RoomView/List.js b/app/views/RoomView/List.js
index 51240c7a0..eeec5dee4 100644
--- a/app/views/RoomView/List.js
+++ b/app/views/RoomView/List.js
@@ -171,9 +171,9 @@ class List extends React.Component {
 
 	onEndReached = debounce(async() => {
 		const {
-			loading, end, messages
+			loading, end, messages, latest = messages[messages.length - 1].ts
 		} = this.state;
-		if (loading || end || messages.length < 50) {
+		if (loading || end) {
 			return;
 		}
 
@@ -185,16 +185,40 @@ class List extends React.Component {
 				// `offset` is `messages.length - 1` because we append thread start to `messages` obj
 				result = await RocketChat.loadThreadMessages({ tmid, rid, offset: messages.length - 1 });
 			} else {
-				result = await RocketChat.loadMessagesForRoom({ rid, t, latest: messages[messages.length - 1].ts });
+				result = await RocketChat.loadMessagesForRoom({ rid, t, latest });
 			}
 
-			this.setState({ end: result.length < 50, loading: false });
+			this.setState({ end: result.length < 50, loading: false, latest: result[result.length - 1].ts }, () => this.loadMoreMessages(result));
 		} catch (e) {
 			this.setState({ loading: false });
 			log(e);
 		}
 	}, 300)
 
+	loadMoreMessages = (result) => {
+		const { end } = this.state;
+
+		if (end) {
+			return;
+		}
+
+		// handle servers with version < 3.0.0
+		let { hideSystemMessages = [] } = this.props;
+		if (!Array.isArray(hideSystemMessages)) {
+			hideSystemMessages = [];
+		}
+
+		if (!hideSystemMessages.length) {
+			return;
+		}
+
+		const hasReadableMessages = result.filter(message => !message.t || (message.t && !hideSystemMessages.includes(message.t))).length > 0;
+		// if this batch doesn't contain any messages that will be displayed, we'll request a new batch
+		if (!hasReadableMessages) {
+			this.onEndReached();
+		}
+	}
+
 	onRefresh = () => this.setState({ refreshing: true }, async() => {
 		const { messages } = this.state;
 		const { rid, tmid } = this.props;