From 751998e980d01122f1eea18b7520a2e91a2d5298 Mon Sep 17 00:00:00 2001
From: Oskar Thoren <ot@oskarthoren.com>
Date: Thu, 4 Jan 2018 23:25:13 +0900
Subject: [PATCH] Intercept received messages and queue them

- Exposes behavior under QUEUE_MESSAGE_ENABLED flag that is turned off in
production.

- Delays messages to allow for reordering of latecoming messages up to 500ms
---
 .env                                         |  1 +
 .env.jenkins                                 |  1 +
 .env.prod                                    |  1 +
 src/status_im/chat/events.cljs               |  1 +
 src/status_im/chat/events/queue_message.cljs | 30 ++++++++++++++++++++
 src/status_im/protocol/handlers.cljs         |  2 +-
 src/status_im/utils/config.cljs              |  1 +
 7 files changed, 36 insertions(+), 1 deletion(-)
 create mode 100644 src/status_im/chat/events/queue_message.cljs

diff --git a/.env b/.env
index 971e63785c..491608bf4e 100644
--- a/.env
+++ b/.env
@@ -7,3 +7,4 @@ OFFLINE_INBOX_ENABLED=1
 LOG_LEVEL=debug
 LOG_LEVEL_STATUS_GO=info
 JSC_ENABLED=1
+QUEUE_MESSAGE_ENABLED=1
\ No newline at end of file
diff --git a/.env.jenkins b/.env.jenkins
index 38fa94b86e..beeff5c1b6 100644
--- a/.env.jenkins
+++ b/.env.jenkins
@@ -7,3 +7,4 @@ OFFLINE_INBOX_ENABLED=1
 LOG_LEVEL=debug
 LOG_LEVEL_STATUS_GO=info
 JSC_ENABLED=0
+QUEUE_MESSAGE_ENABLED=1
diff --git a/.env.prod b/.env.prod
index 18f4650c3f..58e7942d0c 100644
--- a/.env.prod
+++ b/.env.prod
@@ -7,3 +7,4 @@ OFFLINE_INBOX_ENABLED=0
 LOG_LEVEL=info
 LOG_LEVEL_STATUS_GO=
 JSC_ENABLED=0
+QUEUE_MESSAGE_ENABLED=0
\ No newline at end of file
diff --git a/src/status_im/chat/events.cljs b/src/status_im/chat/events.cljs
index f5020b7316..3d963d14d0 100644
--- a/src/status_im/chat/events.cljs
+++ b/src/status_im/chat/events.cljs
@@ -20,6 +20,7 @@
             status-im.chat.events.commands
             status-im.chat.events.requests
             status-im.chat.events.animation
+            status-im.chat.events.queue-message
             status-im.chat.events.receive-message
             status-im.chat.events.sign-up
             status-im.chat.events.console
diff --git a/src/status_im/chat/events/queue_message.cljs b/src/status_im/chat/events/queue_message.cljs
new file mode 100644
index 0000000000..eca1d67bb6
--- /dev/null
+++ b/src/status_im/chat/events/queue_message.cljs
@@ -0,0 +1,30 @@
+(ns status-im.chat.events.queue-message
+  (:require-macros [cljs.core.async.macros :as async-macros])
+  (:require [cljs.core.async :as async]
+            [re-frame.core :as re-frame]
+            [status-im.utils.config :as config]
+            [status-im.utils.pre-receiver :as pre-receiver]
+            [status-im.utils.handlers :as handlers]))
+
+;; We queue messaged before receiving them to allow lagging messages to catch up.
+;; This ensures proper ordering from a user's POV the vast majority of the time.
+
+;; XXX(oskarth): Hacky def, consider better encapsulation
+(when config/queue-message-enabled?
+  (def in-ch (pre-receiver/start!
+              {:delay-ms 500
+               :reorder? true
+               :add-fn   #(re-frame/dispatch [:chat-received-message/add %])})))
+
+;; NOTE(oskarth): in-ch is assumed to exist
+(re-frame/reg-fx
+ ::queue-message
+ (fn [message]
+   (async/put! in-ch message)))
+
+(handlers/register-handler-fx
+ :pre-received-message
+ (fn [_ [_ message]]
+   (if config/queue-message-enabled?
+     {::queue-message message}
+     {:dispatch [:chat-received-message/add message]})))
diff --git a/src/status_im/protocol/handlers.cljs b/src/status_im/protocol/handlers.cljs
index d0c31f8965..d7fe485137 100644
--- a/src/status_im/protocol/handlers.cljs
+++ b/src/status_im/protocol/handlers.cljs
@@ -316,7 +316,7 @@
               route-fx (case type
                          (:message
                           :group-message
-                          :public-group-message) {:dispatch [:chat-received-message/add (transform-protocol-message message)]} 
+                          :public-group-message) {:dispatch [:pre-received-message (transform-protocol-message message)]}
                          :pending                (cond-> {::pending-messages-save message}
                                                    chat-message
                                                    (assoc :dispatch
diff --git a/src/status_im/utils/config.cljs b/src/status_im/utils/config.cljs
index 8d9f5d6d2e..e42b2c1277 100644
--- a/src/status_im/utils/config.cljs
+++ b/src/status_im/utils/config.cljs
@@ -30,3 +30,4 @@
       keyword))
 
 (def jsc-enabled? (enabled? (get-config :JSC_ENABLED 0)))
+(def queue-message-enabled? (enabled? (get-config :QUEUE_MESSAGE_ENABLED 0)))