core: sort chat previews by chat ts (#1625)

src/Simplex/Chat/Migrations/M20221222_chat_ts.hs

@@ -0,0 +1,14 @@
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Chat.Migrations.M20221222_chat_ts where
+
+import Database.SQLite.Simple (Query)
+import Database.SQLite.Simple.QQ (sql)
+
+m20221222_chat_ts :: Query
+m20221222_chat_ts =
+  [sql|
+ALTER TABLE contacts ADD COLUMN chat_ts TEXT;
+
+ALTER TABLE groups ADD COLUMN chat_ts TEXT;
+|]

src/Simplex/Chat/Migrations/chat_schema.sql

@@ -60,6 +60,7 @@ CREATE TABLE contacts(
   unread_chat INTEGER DEFAULT 0 CHECK(unread_chat NOT NULL),
   contact_used INTEGER DEFAULT 0 CHECK(contact_used NOT NULL),
   user_preferences TEXT DEFAULT '{}' CHECK(user_preferences NOT NULL),
+  chat_ts TEXT,
   FOREIGN KEY(user_id, local_display_name)
   REFERENCES display_names(user_id, local_display_name)
   ON DELETE CASCADE
@@ -130,7 +131,8 @@ CREATE TABLE groups(
   chat_item_id INTEGER DEFAULT NULL REFERENCES chat_items ON DELETE SET NULL,
   enable_ntfs INTEGER,
   host_conn_custom_user_profile_id INTEGER REFERENCES contact_profiles ON DELETE SET NULL,
-  unread_chat INTEGER DEFAULT 0 CHECK(unread_chat NOT NULL), -- received
+  unread_chat INTEGER DEFAULT 0 CHECK(unread_chat NOT NULL),
+  chat_ts TEXT, -- received
   FOREIGN KEY(user_id, local_display_name)
   REFERENCES display_names(user_id, local_display_name)
   ON DELETE CASCADE