Save and sort sheets by last access time

lib/home_page.dart

@@ -25,50 +25,75 @@ class _MyHomePageState extends State<MyHomePage> {
   }
 
   Future<List<Sheet>> acquireSheets() async {
-    final url = await _storageHelper.read(StorageKey.url);
-    final jwt = await _storageHelper.read(StorageKey.jwt);
+    final url = await _storageHelper.readSecure(SecureStorageKey.url);
+    final jwt = await _storageHelper.readSecure(SecureStorageKey.jwt);
     apiClient = ApiClient(baseUrl: url!, token: jwt);
     // TODO: check if really logged in
     final sheets = await apiClient!.fetchSheets();
     log.info("${sheets.length} sheets fetched");
+    final sheetsSorted = await sortSheetsByAccessTime(sheets);
+    log.info("${sheetsSorted.length} sheets sorted");
+    return sheetsSorted;
+  }
+
+  Future<List<Sheet>> sortSheetsByAccessTime(List<Sheet> sheets) async {
+    final accessTimes = await _storageHelper.readSheetAccessTimes();
+
+    sheets.sort((a, b) {
+      final dateA = accessTimes[a.uuid];
+      final dateB = accessTimes[b.uuid];
+
+      if (dateB == null) {
+        // b has no date, sort below a
+        return -1;
+      } else if (dateA == null) {
+        // a has no date, sort below b
+        return 1;
+      } else {
+        // compare both and sort by date
+        return dateB.compareTo(dateA);
+      }
+    });
+
     return sheets;
   }
 
   @override
   Widget build(BuildContext context) {
     return Scaffold(
-      appBar: AppBar(
-        title: const Text("My Sheets"),
-      ),
+      appBar: AppBar(title: const Text("My Sheets")),
       body: FutureBuilder(
-          future: acquireSheets(),
-          builder: (BuildContext context, AsyncSnapshot<List<Sheet>> snapshot) {
-            if (snapshot.hasData) {
-              return SheetsWidget(
-                sheets: snapshot.data!,
-                callback: (sheet) => Navigator.push(
+        future: acquireSheets(),
+        builder: (BuildContext context, AsyncSnapshot<List<Sheet>> snapshot) {
+          if (snapshot.hasData) {
+            return SheetsWidget(
+              sheets: snapshot.data!,
+              onSheetOpenRequest: (sheet) {
+                _storageHelper.writeSheetAccessTime(sheet.uuid, DateTime.now());
+                Navigator.push(
                   context,
                   MaterialPageRoute(
-                    builder: (context) => SheetViewerPage(
-                      sheet: sheet,
-                      apiClient: apiClient!,
-                    ),
+                    builder: (context) =>
+                        SheetViewerPage(sheet: sheet, apiClient: apiClient!),
                   ),
-                ),
-              );
-            } else if (snapshot.hasError) {
-              return Center(
-                  child: Text(
-                      style: Theme.of(context)
-                          .textTheme
-                          .displaySmall!
-                          .copyWith(color: Colors.red),
-                      textAlign: TextAlign.center,
-                      snapshot.error.toString()));
-            } else {
-              return const Center(child: CircularProgressIndicator());
-            }
-          }),
+                );
+              },
+            );
+          } else if (snapshot.hasError) {
+            return Center(
+              child: Text(
+                style: Theme.of(
+                  context,
+                ).textTheme.displaySmall!.copyWith(color: Colors.red),
+                textAlign: TextAlign.center,
+                snapshot.error.toString(),
+              ),
+            );
+          } else {
+            return const Center(child: CircularProgressIndicator());
+          }
+        },
+      ),
     );
   }
 }