Automatically reload messages on reconnect

Signed-off-by: Janne Koschinski <janne@kuschku.de>

app/src/main/java/de/kuschku/quasseldroid/ui/chat/messages/MessageListFragment.kt

@@ -40,9 +40,12 @@ import com.bumptech.glide.Glide
 import com.bumptech.glide.ListPreloader
 import com.bumptech.glide.integration.recyclerview.RecyclerViewPreloader
 import com.bumptech.glide.util.FixedPreloadSizeProvider
+import de.kuschku.libquassel.connection.ConnectionState
 import de.kuschku.libquassel.protocol.BufferId
 import de.kuschku.libquassel.protocol.MsgId
 import de.kuschku.libquassel.quassel.syncables.BufferSyncer
+import de.kuschku.libquassel.session.SessionManager
+import de.kuschku.libquassel.util.helpers.mapSwitchMap
 import de.kuschku.libquassel.util.helpers.value
 import de.kuschku.libquassel.util.irc.HostmaskHelper
 import de.kuschku.quasseldroid.GlideApp
@@ -246,8 +249,7 @@ class MessageListFragment : ServiceBoundFragment() {
     }
 
     var isScrolling = false
-    messageList.addOnScrollListener(
-      object : RecyclerView.OnScrollListener() {
+    messageList.addOnScrollListener(object : RecyclerView.OnScrollListener() {
       override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
         val canScrollDown = recyclerView.canScrollVertically(1)
         val isScrollingDown = dy > 0
@@ -314,6 +316,15 @@ class MessageListFragment : ServiceBoundFragment() {
       swipeRefreshLayout.isEnabled = (bufferId != null || bufferId != -1)
     })
 
+    viewModel.sessionManager.mapSwitchMap(SessionManager::state).distinctUntilChanged().toLiveData().observe(
+      this, Observer {
+      if (it?.orNull() == ConnectionState.CONNECTED) {
+        runInBackgroundDelayed(16) {
+          loadMore()
+        }
+      }
+    })
+
     var previousVisible = -1L
     viewModel.buffer.toFlowable(BackpressureStrategy.LATEST).switchMap { buffer ->
       database.filtered().listenRx(accountId, buffer).switchMap { filtered ->