Add basic shop screen

This removes the "support me" button on the home screen and replaces it
with a link to the future shop. The rewarded video ad can be reached
from there. I also cleaned up the localizations and reformated
lib/screens/home.dart.

lib/localizations.dart

@@ -15,16 +15,15 @@ class ChristmasCatsLocalizations {
       'records3': '3. %i',
       'back': 'Back',
       'intro': 'Introduction',
-      'ad': 'Support me',
+      'shop': 'Shop',
+      'coins': '%i Coins',
+      'getCoins': 'Get coins',
+      'adLoading': 'Ad loading',
       'noAds': 'No ads available',
       'poem': 'Cats are climbing Christmas trees,\n'
           'The trees are getting wiggly,\n'
           'You\'ll get a lot of trouble,\n'
           'If you don\'t tap them quickly.',
-      'intro1': 'Cats are climbing Christmas trees,',
-      'intro2': 'The trees are getting wiggly,',
-      'intro3': 'You\'ll get a lot of trouble,',
-      'intro4': 'If You don\'t tap them quickly.',
       'paused': 'Paused',
       'unpause': 'Continue',
       'exit': 'Exit',
@@ -42,16 +41,15 @@ class ChristmasCatsLocalizations {
       'records3': '3. %i',
       'back': 'Zurück',
       'intro': 'Einführung',
-      'ad': 'Mich unterstützen',
+      'shop': 'Laden',
+      'coins': '%i Münzen',
+      'adLoading': 'Werbung wird geladen',
       'noAds': 'Keine Werbung verfügbar',
+      'getCoins': 'Münzen bekommen',
       'poem': 'Katzen, die auf Tannen steigen,\n'
           'Welche sich gefährlich neigen,\n'
           'Du musst auf die Tannen tippen,\n'
           'Denn sonst werden diese kippen!',
-      'intro1': 'Katzen, die auf Tannen steigen,',
-      'intro2': 'Welche sich gefährlich neigen,',
-      'intro3': 'Du musst auf die Tannen tippen,',
-      'intro4': 'Denn sonst werden diese kippen!',
       'paused': 'Pausiert',
       'unpause': 'Weiter',
       'exit': 'Beenden',
@@ -77,13 +75,12 @@ class ChristmasCatsLocalizations {
   String get records3 => localizedStrings['records3'];
   String get back => localizedStrings['back'];
   String get intro => localizedStrings['intro'];
-  String get ad => localizedStrings['ad'];
+  String get shop => localizedStrings['shop'];
+  String get coins => localizedStrings['coins'];
+  String get adLoading => localizedStrings['adLoading'];
   String get noAds => localizedStrings['noAds'];
+  String get getCoins => localizedStrings['getCoins'];
   String get poem => localizedStrings['poem'];
-  String get intro1 => localizedStrings['intro1'];
-  String get intro2 => localizedStrings['intro2'];
-  String get intro3 => localizedStrings['intro3'];
-  String get intro4 => localizedStrings['intro4'];
   String get paused => localizedStrings['paused'];
   String get unpause => localizedStrings['unpause'];
   String get exit => localizedStrings['exit'];

lib/screens/home.dart

@@ -1,4 +1,3 @@
-import 'package:firebase_admob/firebase_admob.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 
@@ -9,6 +8,7 @@ import '../widgets/menu_entry.dart';
 import 'game.dart';
 import 'intro.dart';
 import 'records.dart';
+import 'shop.dart';
 
 class HomeScreen extends StatelessWidget {
   @override
@@ -24,51 +24,39 @@ class HomeScreen extends StatelessWidget {
           MenuEntry(
             text: localizations.play,
             onTap: () => Navigator.push(
-                context,
-                MaterialPageRoute(
-                  builder: (context) => GameScreen(),
-                )),
+              context,
+              MaterialPageRoute(
+                builder: (context) => GameScreen(),
+              ),
+            ),
           ),
           MenuEntry(
             text: localizations.records,
             onTap: () => Navigator.push(
-                context,
-                MaterialPageRoute(
-                  builder: (context) => RecordsScreen(),
-                )),
+              context,
+              MaterialPageRoute(
+                builder: (context) => RecordsScreen(),
+              ),
+            ),
           ),
           MenuEntry(
             text: localizations.intro,
             onTap: () => Navigator.push(
-                context,
-                MaterialPageRoute(
-                  builder: (context) => IntroScreen(),
-                )),
+              context,
+              MaterialPageRoute(
+                builder: (context) => IntroScreen(),
+              ),
+            ),
           ),
           Builder(
             builder: (context) => MenuEntry(
-              text: localizations.ad,
-              onTap: () {
-                final ad = RewardedVideoAd.instance;
-
-                ad.listener = (event, {rewardAmount, rewardType}) {
-                  if (event == RewardedVideoAdEvent.loaded) {
-                    ad.show();
-                  } else if (event == RewardedVideoAdEvent.failedToLoad) {
-                    Scaffold.of(context).showSnackBar(SnackBar(
-                      content: Text(localizations.noAds),
-                      duration: const Duration(seconds: 2),
-                    ));
-                  } else if (event == RewardedVideoAdEvent.rewarded) {
-                    // TODO: Reward user
-                  }
-                };
-
-                ad.load(
-                  adUnitId: 'ca-app-pub-4129701777413448/6712208196',
-                  targetingInfo: MobileAdTargetingInfo(),
-                );
-              },
+              text: localizations.shop,
+              onTap: () => Navigator.push(
+                context,
+                MaterialPageRoute(
+                  builder: (context) => ShopScreen(),
+                ),
+              ),
             ),
           ),
           MenuEntry(

lib/screens/shop.dart

@@ -0,0 +1,63 @@
+import 'package:firebase_admob/firebase_admob.dart';
+import 'package:flutter/foundation.dart';
+import 'package:flutter/material.dart';
+import 'package:sprintf/sprintf.dart';
+
+import '../localizations.dart';
+import '../storage.dart';
+import '../widgets/menu.dart';
+import '../widgets/menu_entry.dart';
+
+class ShopScreen extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    final localizations = ChristmasCatsLocalizations.of(context);
+
+    return Scaffold(
+      resizeToAvoidBottomInset: false,
+      body: StreamBuilder(
+        stream: storage.coins,
+        builder: (context, snapshot) => Menu(
+          title: localizations.shop,
+          subtitle: sprintf(localizations.coins, [snapshot?.data ?? 0]),
+          children: <Widget>[
+            MenuEntry(
+              text: localizations.getCoins,
+              onTap: () {
+                final scaffold = Scaffold.of(context);
+                scaffold.showSnackBar(SnackBar(
+                  content: Text(localizations.adLoading),
+                  // Show it until the ad is loaded
+                  duration: Duration(minutes: 1),
+                ));
+
+                final ad = RewardedVideoAd.instance;
+                ad.listener = (event, {rewardAmount, rewardType}) {
+                  scaffold.removeCurrentSnackBar();
+                  if (event == RewardedVideoAdEvent.loaded) {
+                    ad.show();
+                  } else if (event == RewardedVideoAdEvent.failedToLoad) {
+                    scaffold.showSnackBar(SnackBar(
+                      content: Text(localizations.noAds),
+                      duration: const Duration(seconds: 2),
+                    ));
+                  } else if (event == RewardedVideoAdEvent.rewarded) {
+                    storage.addCoins(rewardAmount);
+                  }
+                };
+
+                ad.load(
+                  adUnitId: kReleaseMode
+                      ? 'ca-app-pub-4129701777413448/6712208196'
+                      : 'ca-app-pub-3940256099942544/5224354917',
+                  targetingInfo: MobileAdTargetingInfo(),
+                );
+              },
+            ),
+          ],
+          showBackButton: true,
+        ),
+      ),
+    );
+  }
+}