refactor: api_types/model: Improve types for typing notifications.

With the addition of stream typing notifications, and soon the migration to
"direct" in place of "private", message type can now be useful to include.

However, note that we don't yet explicitly specify the type for the
direct/private message form, since this was added only in ZFL 58, Zulip 4.0.

zulipterminal/api_types.py

@@ -17,12 +17,6 @@
 
 RESOLVED_TOPIC_PREFIX = "✔ "
 
-# Refer to https://zulip.com/api/set-typing-status for the protocol
-# on typing notifications sent by clients.
-TYPING_STARTED_WAIT_PERIOD = 10
-TYPING_STOPPED_WAIT_PERIOD = 5
-
-
 ###############################################################################
 # These values are in the register response from ZFL 53
 # Before this feature level, they had the listed default (fixed) values
@@ -42,6 +36,37 @@
 MessageType = Union[DirectMessageString, StreamMessageString]
 
 
+###############################################################################
+# Parameters to pass in request to:
+#   https://zulip.com/api/set-typing-status
+# Refer to the top of that page for the expected protocol clients should observe
+#
+# NOTE: `to` field could be email until ZFL 11/3.0; ids were possible from 2.0+
+
+# Timing parameters for when notifications should occur
+TYPING_STARTED_WAIT_PERIOD: Final = 10
+TYPING_STOPPED_WAIT_PERIOD: Final = 5
+TYPING_STARTED_EXPIRY_PERIOD: Final = 15  # TODO: Needs implementation in ZT
+
+TypingStatusChange = Literal["start", "stop"]
+
+
+class DirectTypingNotification(TypedDict):
+    # The type field was added in ZFL 58, Zulip 4.0, so don't require it yet
+    ## type: DirectMessageString
+    op: TypingStatusChange
+    to: List[int]
+
+
+# NOTE: Not yet implemented in ZT
+# New in ZFL 58, Zulip 4.0
+class StreamTypingNotification(TypedDict):
+    type: StreamMessageString
+    op: TypingStatusChange
+    to: List[int]  # NOTE: Length 1, stream id
+    topic: str
+
+
 ###############################################################################
 # Parameter to pass in request to:
 #   https://zulip.com/api/send-message

zulipterminal/model.py

@@ -27,14 +27,15 @@
 
 import zulip
 from bs4 import BeautifulSoup
-from typing_extensions import Literal, TypedDict
+from typing_extensions import TypedDict
 
 from zulipterminal import unicode_emojis
 from zulipterminal.api_types import (
     MAX_MESSAGE_LENGTH,
     MAX_STREAM_NAME_LENGTH,
     MAX_TOPIC_NAME_LENGTH,
     Composition,
+    DirectTypingNotification,
     EditPropagateMode,
     Event,
     PrivateComposition,
@@ -44,6 +45,7 @@
     StreamComposition,
     StreamMessageUpdateRequest,
     Subscription,
+    TypingStatusChange,
 )
 from zulipterminal.config.keys import primary_key_for_command
 from zulipterminal.config.symbols import STREAM_TOPIC_SEPARATOR
@@ -513,12 +515,12 @@ def mark_message_ids_as_read(self, id_list: List[int]) -> None:
 
     @asynch
     def send_typing_status_by_user_ids(
-        self, recipient_user_ids: List[int], *, status: Literal["start", "stop"]
+        self, recipient_user_ids: List[int], *, status: TypingStatusChange
     ) -> None:
         if not self.user_settings()["send_private_typing_notifications"]:
             return
         if recipient_user_ids:
-            request = {"to": recipient_user_ids, "op": status}
+            request: DirectTypingNotification = {"to": recipient_user_ids, "op": status}
             response = self.client.set_typing_status(request)
             display_error_if_present(response, self.controller)
         else: