home_page: implement shuffling

lib/home_page.dart

@@ -25,7 +25,7 @@ class _MyHomePageState extends State<MyHomePage> {
   String? appName;
   String? appVersion;
   bool shuffling = false;
-  late final Future<List<Sheet>> sheets;
+  late Future<List<Sheet>> sheets;
 
   @override
   void initState() {
@@ -87,6 +87,18 @@ class _MyHomePageState extends State<MyHomePage> {
     ).pushReplacement(MaterialPageRoute(builder: (_) => LoginPage()));
   }
 
+  void switchShufflingState(bool newState) async {
+    if (newState) {
+      (await sheets).shuffle();
+    } else {
+      sheets = sortSheetsByAccessTime(await sheets);
+    }
+
+    setState(() {
+      shuffling = newState;
+    });
+  }
+
   Drawer _buildDrawer() {
     return Drawer(
       child: SafeArea(
@@ -104,22 +116,17 @@ class _MyHomePageState extends State<MyHomePage> {
                       color: shuffling ? Colors.blue : null,
                     ),
                     title: const Text('Shuffle'),
-                    trailing: Switch(
-                      value: shuffling,
-                      onChanged: (value) {
-                        setState(() {
-                          shuffling = value;
-                        });
-                      },
-                    ),
-                  ),
-                  ListTile(
-                    leading: const Icon(Icons.sync),
-                    title: const Text('Sync Mode'),
                     onTap: () {
-                      // TODO
+                      switchShufflingState(!shuffling);
                     },
                   ),
+                  // ListTile(
+                  //   leading: const Icon(Icons.sync),
+                  //   title: const Text('Sync Mode'),
+                  //   onTap: () {
+                  //     // TODO
+                  //   },
+                  // ),
                   ListTile(
                     leading: const Icon(Icons.logout),
                     title: const Text('Logout'),