load messages on scroll

Former-commit-id: ff1291dac0

src/status_im/chat/handlers.cljs

@@ -27,13 +27,12 @@
     (assoc db :show-actions show-actions)))
 
 (register-handler :load-more-messages
-  (fn [db _]
-    db
-    ;; TODO implement
-    #_(let [chat-id      (get-in db [:chat :current-chat-id])
-            messages     [:chats chat-id :messages]
-            new-messages (gen-messages 10)]
-        (update-in db messages concat new-messages))))
+  debug
+  (fn [{:keys [current-chat-id] :as db} _]
+    (let [messages-path [:chats current-chat-id :messages]
+          messages (get-in db messages-path)
+          new-messages (messages/get-messages current-chat-id (count messages))]
+      (update-in db messages-path concat new-messages))))
 
 (defn safe-trim [s]
   (when (string? s)
@@ -287,10 +286,8 @@
 
 (defn load-messages!
   ([db] (load-messages! db nil))
-  ([db _]
-   (->> (:current-chat-id db)
-        messages/get-messages
-        (assoc db :messages))))
+  ([{:keys [current-chat-id] :as db} _]
+   (assoc db :messages (messages/get-messages current-chat-id))))
 
 (defn init-chat
   ([db] (init-chat db nil))

src/status_im/constants.cljs

@@ -15,3 +15,5 @@
 
 (def response-input-hiding-duration 100)
 (def response-suggesstion-resize-duration 100)
+
+(def default-number-of-messages 10)

src/status_im/models/messages.cljs

@@ -3,7 +3,6 @@
             [re-frame.core :refer [dispatch]]
             [cljs.reader :refer [read-string]]
             [status-im.utils.random :refer [timestamp]]
-            [status-im.db :as db]
             [status-im.utils.logging :as log]
             [clojure.string :refer [join split]]
             [clojure.walk :refer [stringify-keys keywordize-keys]]
@@ -46,16 +45,19 @@
     #{c/content-type-command c/content-type-command-request}
     type))
 
-(defn get-messages [chat-id]
+(defn get-messages
+  ([chat-id] (get-messages chat-id 0))
+  ([chat-id from]
     (->> (-> (r/get-by-field :msgs :chat-id chat-id)
              (r/sorted :timestamp :desc)
+             (r/page from (+ from c/default-number-of-messages))
              (r/collection->map))
          (into '())
          reverse
          (map (fn [{:keys [content-type] :as message}]
                 (if (command-type? content-type)
                   (update message :content str-to-map)
-                message)))))
+                  message))))))
 
 (defn update-message! [{:keys [msg-id] :as msg}]
   (log/debug "update-message!" msg)