[🐴] State transitions (#3880)

* Handle init/resume/suspend/background and polling

* Add debug and temp guard

* Make state transitions sync

* Make init sync also

* Checkpoint: confusing but working state machine

* Reducer-esque

* Remove poll events

* Guard fetchConvo

(cherry picked from commit 8385579d31500bb4bfb60afeecdc1eb3ddd7e747)

* Clean up polling, make sync

(cherry picked from commit 7f75cd04c3bf81c94662785748698640a84bef51)

* Update history handling

(cherry picked from commit b82b552ba4040adf7ead2377541132a386964ff8)

* Check for screen focus in app state listener

* Get rid of ad-hoc status checks

src/screens/Messages/Conversation/MessageListError.tsx

@@ -18,10 +18,10 @@ export function MessageListError({
   const {_} = useLingui()
   const message = React.useMemo(() => {
     return {
-      [ConvoItemError.HistoryFailed]: _(msg`Failed to load past messages.`),
-      [ConvoItemError.ResumeFailed]: _(
+      [ConvoItemError.Network]: _(
         msg`There was an issue connecting to the chat.`,
       ),
+      [ConvoItemError.HistoryFailed]: _(msg`Failed to load past messages.`),
       [ConvoItemError.PollFailed]: _(
         msg`This chat was disconnected due to a network error.`,
       ),

src/screens/Messages/Conversation/index.tsx

@@ -18,6 +18,7 @@ import {PreviewableUserAvatar} from 'view/com/util/UserAvatar'
 import {CenteredView} from 'view/com/util/Views'
 import {MessagesList} from '#/screens/Messages/Conversation/MessagesList'
 import {atoms as a, useBreakpoints, useTheme} from '#/alf'
+import {Button, ButtonText} from '#/components/Button'
 import {ConvoMenu} from '#/components/dms/ConvoMenu'
 import {ListMaybePlaceholder} from '#/components/Lists'
 import {Text} from '#/components/Typography'
@@ -51,8 +52,21 @@ function Inner() {
   }
 
   if (chat.status === ConvoStatus.Error) {
-    // TODO error
-    return null
+    // TODO
+    return (
+      <View>
+        <CenteredView style={{flex: 1}} sideBorders>
+          <Text>Something went wrong</Text>
+          <Button
+            label="Retry"
+            onPress={() => {
+              chat.error.retry()
+            }}>
+            <ButtonText>Retry</ButtonText>
+          </Button>
+        </CenteredView>
+      </View>
+    )
   }
 
   /*