opt.: add tip for upgrading pkgs (#326)

lib/view/widget/count_down_btn.dart

@@ -0,0 +1,69 @@
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:toolbox/core/extension/context/locale.dart';
+
+final class CountDownBtn extends StatefulWidget {
+  final int seconds;
+  final String text;
+  final Color? afterColor;
+  final VoidCallback onTap;
+
+  const CountDownBtn({
+    super.key,
+    required this.onTap,
+    this.seconds = 3,
+    this.text = 'Go',
+    this.afterColor,
+  });
+
+  @override
+  State<CountDownBtn> createState() => _CountDownBtnState();
+}
+
+final class _CountDownBtnState extends State<CountDownBtn> {
+  late int _seconds = widget.seconds;
+  Timer? _timer;
+
+  @override
+  void initState() {
+    super.initState();
+    _startCountDown();
+  }
+
+  @override
+  void dispose() {
+    _timer?.cancel();
+    super.dispose();
+  }
+
+  bool get isCounting => _seconds > 0;
+
+  void _startCountDown() {
+    if (isCounting) return;
+    _timer = Timer.periodic(const Duration(seconds: 1), (timer) {
+      if (!isCounting) {
+        _timer?.cancel();
+      }
+      setState(() {
+        _seconds--;
+      });
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return TextButton(
+      onPressed: () {
+        if (isCounting) return;
+        widget.onTap();
+      },
+      child: Text(
+        isCounting ? '$_seconds${l10n.second}' : widget.text,
+        style: TextStyle(
+          color: _seconds > 0 ? Colors.grey : widget.afterColor,
+        ),
+      ),
+    );
+  }
+}

lib/view/widget/server_func_btns.dart

@@ -18,6 +18,7 @@ import 'package:toolbox/data/res/path.dart';
 import 'package:toolbox/data/res/provider.dart';
 import 'package:toolbox/data/res/store.dart';
 import 'package:toolbox/data/res/ui.dart';
+import 'package:toolbox/view/widget/count_down_btn.dart';
 
 import '../../core/route.dart';
 import '../../core/utils/server.dart';
@@ -279,12 +280,13 @@ Future<void> _onPkg(BuildContext context, ServerPrivateInfo spi) async {
   final gotoUpgrade = await context.showRoundDialog<bool>(
     title: Text(l10n.attention),
     child: SingleChildScrollView(
-      child: Text('${l10n.foundNUpdate(upgradeable.length)}\n\n$upgradeCmd'),
+      child: Text('${l10n.pkgUpgradeTip}\n${l10n.foundNUpdate(upgradeable.length)}\n\n$upgradeCmd'),
     ),
     actions: [
-      TextButton(
-        onPressed: () => context.pop(true),
-        child: Text(l10n.update),
+      CountDownBtn(
+        onTap: () => context.pop(true),
+        text: l10n.update,
+        afterColor: Colors.red,
       ),
     ],
   );