Revert " #4755 Combining consecutive user join/leave system messages to single message and few other changes." (#7072)

* Revert "PLT-6603: Don't return all posts on invalid query. (#7061)"

This reverts commit 25a2013890c7e07b4621fa9b18342e7f35363049.

* Revert " #4755 Combining consecutive user join/leave system messages to single message and few other changes. (#5945)"

This reverts commit 8a91235fb3cdc8d094dbc2eaa0d7baa447132b3c.

1 files changed, 44 insertions, 117 deletions

diff --git a/app/channel.go b/app/channel.go
index 083700795..03df0e800 100644
--- a/app/channel.go
+++ b/app/channel.go
@@ -897,75 +897,19 @@ func JoinChannel(channel *model.Channel, userId string) *model.AppError {
 	return nil
 }
 
-func createUserActivitySystemMessage(channel *model.Channel, user *model.User, otherUsername, messageType, message string) *model.AppError {
-	props := model.StringInterface{"username": user.Username}
-	if messageType == model.POST_ADD_TO_CHANNEL {
-		props["addedUsername"] = otherUsername
-	}
-
-	if messageType == model.POST_REMOVE_FROM_CHANNEL {
-		props["removedUsername"] = user.Username
-		delete(props, "username")
-	}
-
+func postJoinChannelMessage(user *model.User, channel *model.Channel) *model.AppError {
 	post := &model.Post{
 		ChannelId: channel.Id,
-		Message:   message,
-		Type:      messageType,
+		Message:   fmt.Sprintf(utils.T("api.channel.join_channel.post_and_forget"), user.Username),
+		Type:      model.POST_JOIN_CHANNEL,
 		UserId:    user.Id,
-		Props:     props,
+		Props: model.StringInterface{
+			"username": user.Username,
+		},
 	}
 
 	if _, err := CreatePost(post, channel.TeamId, false); err != nil {
-		return model.NewLocAppError("createUserActivitySystemMessage", "api.channel.create_user_activity_post.error", nil, err.Error())
-	}
-
-	return nil
-}
-
-func updateUserActivitySystemMessage(post *model.Post, username, otherUsername, messageType, messageToAdd string) *model.AppError {
-	post.Message += " " + messageToAdd
-	props := model.StringMap{"type": messageType, "username": username}
-	if messageType == model.POST_ADD_TO_CHANNEL {
-		props["addedUsername"] = otherUsername
-	}
-
-	if messageType == model.POST_REMOVE_FROM_CHANNEL {
-		props["removedUsername"] = username
-		delete(props, "username")
-	}
-
-	if val, ok := post.Props["messages"]; ok {
-		post.Props["messages"] = append(val.([]interface{}), props)
-	} else {
-		oldProps := make(model.StringInterface)
-		for key, value := range post.Props {
-			oldProps[key] = value
-		}
-		oldProps["type"] = post.Type
-		post.Props["messages"] = []interface{}{oldProps, props}
-	}
-
-	if _, err := UpdatePost(post, false); err != nil {
-		return model.NewLocAppError("updateUserActivitySystemMessage", "api.channel.update_user_activity_post.error", nil, err.Error())
-	}
-
-	return nil
-}
-
-func postJoinChannelMessage(user *model.User, channel *model.Channel) *model.AppError {
-	message := fmt.Sprintf(utils.T("api.channel.join_channel.post_and_forget"), user.Username)
-
-	if post, err := GetLastPostForChannel(channel.Id); err != nil {
-		return err
-	} else if post.IsUserActivitySystemMessage() {
-		if err := updateUserActivitySystemMessage(post, user.Username, "", model.POST_JOIN_CHANNEL, message); err != nil {
-			return err
-		}
-	} else {
-		if err := createUserActivitySystemMessage(channel, user, "", model.POST_JOIN_CHANNEL, message); err != nil {
-			return err
-		}
+		return model.NewLocAppError("postJoinChannelMessage", "api.channel.post_user_add_remove_message_and_forget.error", nil, err.Error())
 	}
 
 	return nil
@@ -1010,64 +954,55 @@ func LeaveChannel(channelId string, userId string) *model.AppError {
 }
 
 func postLeaveChannelMessage(user *model.User, channel *model.Channel) *model.AppError {
-	message := fmt.Sprintf(utils.T("api.channel.leave.left"), user.Username)
+	post := &model.Post{
+		ChannelId: channel.Id,
+		Message:   fmt.Sprintf(utils.T("api.channel.leave.left"), user.Username),
+		Type:      model.POST_LEAVE_CHANNEL,
+		UserId:    user.Id,
+		Props: model.StringInterface{
+			"username": user.Username,
+		},
+	}
 
-	if post, err := GetLastPostForChannel(channel.Id); err != nil {
-		return err
-	} else if post.IsUserActivitySystemMessage() {
-		if err := updateUserActivitySystemMessage(post, user.Username, "", model.POST_LEAVE_CHANNEL, message); err != nil {
-			return err
-		}
-	} else {
-		if err := createUserActivitySystemMessage(channel, user, "", model.POST_LEAVE_CHANNEL, message); err != nil {
-			return err
-		}
+	if _, err := CreatePost(post, channel.TeamId, false); err != nil {
+		return model.NewLocAppError("postLeaveChannelMessage", "api.channel.post_user_add_remove_message_and_forget.error", nil, err.Error())
 	}
 
 	return nil
 }
 
 func PostAddToChannelMessage(user *model.User, addedUser *model.User, channel *model.Channel) *model.AppError {
-	message := fmt.Sprintf(utils.T("api.channel.add_member.added"), user.Username, addedUser.Username)
-
-	if post, err := GetLastPostForChannel(channel.Id); err != nil {
-		return err
-	} else if post.IsUserActivitySystemMessage() {
-		if err := updateUserActivitySystemMessage(post, user.Username, addedUser.Username, model.POST_ADD_TO_CHANNEL, message); err != nil {
-			return err
-		}
+	post := &model.Post{
+		ChannelId: channel.Id,
+		Message:   fmt.Sprintf(utils.T("api.channel.add_member.added"), addedUser.Username, user.Username),
+		Type:      model.POST_ADD_TO_CHANNEL,
+		UserId:    user.Id,
+		Props: model.StringInterface{
+			"username":      user.Username,
+			"addedUsername": addedUser.Username,
+		},
+	}
 
-		SendNotificationsForSystemMessageAddRemove(user, addedUser, channel, post)
-	} else {
-		if err := createUserActivitySystemMessage(channel, user, addedUser.Username, model.POST_ADD_TO_CHANNEL, message); err != nil {
-			return err
-		}
+	if _, err := CreatePost(post, channel.TeamId, false); err != nil {
+		return model.NewLocAppError("postAddToChannelMessage", "api.channel.post_user_add_remove_message_and_forget.error", nil, err.Error())
 	}
 
 	return nil
 }
 
 func PostRemoveFromChannelMessage(removerUserId string, removedUser *model.User, channel *model.Channel) *model.AppError {
-	message := fmt.Sprintf(utils.T("api.channel.remove_member.removed"), removedUser.Username)
-
-	removerUser, err := GetUser(removerUserId)
-	if err != nil {
-		fmt.Printf("err: %+v\n", err)
-		return err
+	post := &model.Post{
+		ChannelId: channel.Id,
+		Message:   fmt.Sprintf(utils.T("api.channel.remove_member.removed"), removedUser.Username),
+		Type:      model.POST_REMOVE_FROM_CHANNEL,
+		UserId:    removerUserId,
+		Props: model.StringInterface{
+			"removedUsername": removedUser.Username,
+		},
 	}
 
-	if post, err := GetLastPostForChannel(channel.Id); err != nil {
-		return err
-	} else if post.IsUserActivitySystemMessage() {
-		if err := updateUserActivitySystemMessage(post, removedUser.Username, removerUser.Username, model.POST_REMOVE_FROM_CHANNEL, message); err != nil {
-			return err
-		}
-
-		SendNotificationsForSystemMessageAddRemove(removerUser, removedUser, channel, post)
-	} else {
-		if err := createUserActivitySystemMessage(channel, removedUser, removerUser.Username, model.POST_ADD_TO_CHANNEL, message); err != nil {
-			return err
-		}
+	if _, err := CreatePost(post, channel.TeamId, false); err != nil {
+		return model.NewLocAppError("postRemoveFromChannelMessage", "api.channel.post_user_add_remove_message_and_forget.error", nil, err.Error())
 	}
 
 	return nil
@@ -1111,28 +1046,20 @@ func RemoveUserFromChannel(userIdToRemove string, removerUserId string, channel
 		return err
 	}
 
-	var userToRemove *model.User
-	if userToRemove, err = GetUser(userIdToRemove); err != nil {
+	var user *model.User
+	if user, err = GetUser(userIdToRemove); err != nil {
 		return err
 	}
 
 	if userIdToRemove == removerUserId {
-		postLeaveChannelMessage(userToRemove, channel)
+		postLeaveChannelMessage(user, channel)
 	} else {
-		go PostRemoveFromChannelMessage(removerUserId, userToRemove, channel)
+		go PostRemoveFromChannelMessage(removerUserId, user, channel)
 	}
 
 	return nil
 }
 
-func GetLastPostForChannel(channelId string) (*model.Post, *model.AppError) {
-	result := <-Srv.Store.Post().GetLastPostForChannel(channelId)
-	if result.Err != nil {
-		return nil, result.Err
-	}
-	return result.Data.(*model.Post), nil
-}
-
 func GetNumberOfChannelsOnTeam(teamId string) (int, *model.AppError) {
 	// Get total number of channels on current team
 	if result := <-Srv.Store.Channel().GetTeamChannels(teamId); result.Err != nil {