feature: HTPC mode startup argument (#358)

Co-authored-by: PartyDonut <PartyDonut@users.noreply.github.com>

lib/util/resolution_checker.dart

@@ -0,0 +1,63 @@
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:screen_retriever/screen_retriever.dart';
+import 'package:window_manager/window_manager.dart';
+
+import 'package:fladder/providers/arguments_provider.dart';
+
+class ResolutionChecker extends ConsumerStatefulWidget {
+  final Widget child;
+  const ResolutionChecker({required this.child, super.key});
+
+  @override
+  ConsumerState<ResolutionChecker> createState() => _ResolutionCheckerState();
+}
+
+class _ResolutionCheckerState extends ConsumerState<ResolutionChecker> {
+  Size? lastResolution;
+  Timer? _timer;
+
+  @override
+  void initState() {
+    super.initState();
+    WidgetsBinding.instance.addPostFrameCallback((value) async {
+      if (ref.read(argumentsStateProvider).htpcMode) {
+        lastResolution = (await screenRetriever.getPrimaryDisplay()).size;
+        _timer = Timer.periodic(const Duration(seconds: 2), (timer) => checkResolution());
+      }
+    });
+  }
+
+  Future<void> checkResolution() async {
+    if (!mounted) return;
+    final newResolution = (await screenRetriever.getPrimaryDisplay()).size;
+    if (lastResolution != newResolution) {
+      lastResolution = newResolution;
+      shouldSetResolution();
+    }
+  }
+
+  Future<void> shouldSetResolution() async {
+    if (lastResolution != null) {
+      final isFullScreen = await windowManager.isFullScreen();
+      if (isFullScreen) {
+        await windowManager.setFullScreen(false);
+      }
+      await windowManager.setFullScreen(true);
+    }
+  }
+
+  @override
+  void dispose() {
+    _timer?.cancel();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return widget.child;
+  }
+}