refactors design to flutter driven service core.

lib/main.dart

@@ -1,6 +1,7 @@
+import 'dart:async';
+
 import 'package:flutter/material.dart';
 import 'package:flutter/foundation.dart';
-import 'package:just_audio_background/just_audio_background.dart';
 import 'package:flutter/services.dart';
 import 'package:timezone/data/latest.dart' as tz;
 import 'app_theme_business_object.dart';
@@ -12,13 +13,7 @@ import 'streaming_audio_business_object.dart';
 Future<void> main() async {
   WidgetsFlutterBinding.ensureInitialized();
   tz.initializeTimeZones();
-  await JustAudioBackground.init(
-    androidNotificationChannelId: 'com.kryzgoflutter.audio.channel',
-    androidNotificationChannelName: 'KRYZ Audio Playback',
-    androidNotificationOngoing: true,
-  );
-
-  WidgetsFlutterBinding.ensureInitialized();
+  unawaited(StreamingAudioBusinessObject.initializeBackgroundAudio());
   await SystemChrome.setPreferredOrientations([
     DeviceOrientation.portraitUp,
     DeviceOrientation.portraitDown,
@@ -139,11 +134,6 @@ class _MainPageState extends State<MainPage> {
     _liveInfo.addListener(_handleLiveInfoChanged);
     _liveInfo.start();
     _playbackChannel.setMethodCallHandler(_handlePlaybackMethodCall);
-    // Tell native that Flutter is ready to receive method calls.
-    // On Android this unblocks any pending auto_play from Android Auto.
-    if (defaultTargetPlatform == TargetPlatform.android) {
-      _playbackChannel.invokeMethod<void>('flutterReady');
-    }
   }
 
   Future<void> _handlePlaybackMethodCall(MethodCall call) async {
@@ -163,19 +153,11 @@ class _MainPageState extends State<MainPage> {
     setState(() {
       // Rebuild when playback state changes from the player.
     });
-
-    _syncAutoPlaybackState();
-  }
-
-  void _syncAutoPlaybackState() {
-    if (defaultTargetPlatform != TargetPlatform.android) return;
-    _playbackChannel.invokeMethod<void>('updatePlaybackState', {
-      'isPlaying': _audio.isPlaying,
-      'isBuffering': _audio.isBuffering,
-    });
   }
 
   void _handleLiveInfoChanged() {
+    _audio.updateMetadataFromLiveInfo(_liveInfo.snapshot);
+
     if (!mounted) {
       return;
     }
@@ -213,8 +195,8 @@ class _MainPageState extends State<MainPage> {
     try {
       await _casting.startCastingLiveStream(
         streamUrl: _audio.streamUrl,
-        title: 'KRYZ Live Stream',
-        subtitle: 'KRYZ Radio',
+        title: _audio.currentTitle,
+        subtitle: _audio.currentSubtitle,
       );
 
       _castStreamStartedForActiveSession = true;