From 57b81bd6796ca4540351785affb7f19a632e195a Mon Sep 17 00:00:00 2001
From: Diego Sampaio <chinello@gmail.com>
Date: Wed, 26 Sep 2018 11:06:25 -0300
Subject: [PATCH] Fix duplicate emails on mentions

---
 .../server/functions/notifications/index.js   |  4 +-
 .../server/lib/sendNotificationsOnMessage.js  | 50 ++++++++++++-------
 .../server/models/Subscriptions.js            |  4 +-
 3 files changed, 37 insertions(+), 21 deletions(-)

diff --git a/packages/rocketchat-lib/server/functions/notifications/index.js b/packages/rocketchat-lib/server/functions/notifications/index.js
index c948bdbc4435..40fd2f03bb9b 100644
--- a/packages/rocketchat-lib/server/functions/notifications/index.js
+++ b/packages/rocketchat-lib/server/functions/notifications/index.js
@@ -58,9 +58,9 @@ export function messageContainsHighlight(message, highlights) {
 	});
 }
 
-export function callJoinRoom(user, rid) {
+export function callJoinRoom(userId, rid) {
 	return new Promise((resolve, reject) => {
-		Meteor.runAsUser(user._id, () => Meteor.call('joinRoom', rid, (error, result) => {
+		Meteor.runAsUser(userId, () => Meteor.call('joinRoom', rid, (error, result) => {
 			if (error) {
 				return reject(error);
 			}
diff --git a/packages/rocketchat-lib/server/lib/sendNotificationsOnMessage.js b/packages/rocketchat-lib/server/lib/sendNotificationsOnMessage.js
index 398207532816..345dc856c54a 100644
--- a/packages/rocketchat-lib/server/lib/sendNotificationsOnMessage.js
+++ b/packages/rocketchat-lib/server/lib/sendNotificationsOnMessage.js
@@ -243,23 +243,39 @@ function sendAllNotifications(message, room) {
 
 	// on public channels, if a mentioned user is not member of the channel yet, he will first join the channel and then be notified based on his preferences.
 	if (room.t === 'c') {
-		const mentions = message.mentions.filter(({ _id }) => _id !== 'here' && _id !== 'all').map(({ _id }) => _id);
-		Promise.all(RocketChat.models.Subscriptions.findByRoomIdAndUserIds(room._id, mentions)
-			.fetch()
-			.map(async(subscription) => {
-				await callJoinRoom(subscription.u, room._id);
-				return subscription;
-			})).then((subscriptions) => subscriptions.forEach((subscription) =>
-			sendNotification({
-				subscription,
-				sender,
-				hasMentionToAll,
-				hasMentionToHere,
-				message,
-				notificationMessage,
-				room,
-				mentionIds,
-			})));
+		// get subscriptions from users already in room (to not send them a notification)
+		const mentions = [...mentionIdsWithoutGroups];
+		RocketChat.models.Subscriptions.findByRoomIdAndUserIds(room._id, mentionIdsWithoutGroups, { fields: { 'u._id': 1 } }).forEach((subscription) => {
+			const index = mentions.indexOf(subscription.u._id);
+			if (index !== -1) {
+				mentions.splice(index, 1);
+			}
+		});
+
+		Promise.all(mentions
+			.map(async(userId) => {
+				await callJoinRoom(userId, room._id);
+
+				return userId;
+			})
+		).then((users) => {
+			users.forEach((userId) => {
+				const subscription = RocketChat.models.Subscriptions.findOneByRoomIdAndUserId(room._id, userId);
+
+				sendNotification({
+					subscription,
+					sender,
+					hasMentionToAll,
+					hasMentionToHere,
+					message,
+					notificationMessage,
+					room,
+					mentionIds,
+				});
+			});
+		}).catch((error) => {
+			throw new Meteor.Error(error);
+		});
 	}
 
 	return message;
diff --git a/packages/rocketchat-lib/server/models/Subscriptions.js b/packages/rocketchat-lib/server/models/Subscriptions.js
index 1315c1df25c0..0c413020da87 100644
--- a/packages/rocketchat-lib/server/models/Subscriptions.js
+++ b/packages/rocketchat-lib/server/models/Subscriptions.js
@@ -158,7 +158,7 @@ class ModelSubscriptions extends RocketChat.models._Base {
 		return subscription && subscription.ls;
 	}
 
-	findByRoomIdAndUserIds(roomId, userIds) {
+	findByRoomIdAndUserIds(roomId, userIds, options) {
 		const query = {
 			rid: roomId,
 			'u._id': {
@@ -166,7 +166,7 @@ class ModelSubscriptions extends RocketChat.models._Base {
 			},
 		};
 
-		return this.find(query);
+		return this.find(query, options);
 	}
 
 	findByRoomIdAndUserIdsOrAllMessages(roomId, userIds) {