import 'package:flutter/services.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:melo/player/audio_effects.dart';
import 'package:shared_preferences/shared_preferences.dart';

void main() {
  TestWidgetsFlutterBinding.ensureInitialized();

  const channel = MethodChannel('de.baka.melo/audio_effects');
  late List<MethodCall> calls;

  void mockChannel({Object? Function(MethodCall call)? handler}) {
    calls = [];
    TestDefaultBinaryMessengerBinding.instance.defaultBinaryMessenger
        .setMockMethodCallHandler(channel, (call) async {
      calls.add(call);
      if (handler != null) return handler(call);
      if (call.method == 'attach') {
        return {
          'bands': [
            {'index': 0, 'centerFrequencyMilliHz': 60000, 'level': 0},
            {'index': 1, 'centerFrequencyMilliHz': 14000000, 'level': 0},
          ],
          'presets': ['Normal', 'Rock'],
          'minLevel': -1500,
          'maxLevel': 1500,
          'bassSupported': true,
          'virtualizerSupported': true,
        };
      }
      return null;
    });
  }

  setUp(() {
    SharedPreferences.setMockInitialValues({});
    mockChannel();
  });

  tearDown(() {
    TestDefaultBinaryMessengerBinding.instance.defaultBinaryMessenger
        .setMockMethodCallHandler(channel, null);
  });

  test('attach liest Bänder, Presets und Grenzen vom Gerät', () async {
    final effects = AudioEffects();

    await effects.attach(42);

    expect(effects.available, isTrue);
    expect(effects.bands.map((b) => b.centerHz), [60, 14000]);
    expect(effects.presets, ['Normal', 'Rock']);
    expect(effects.minLevel, -1500);
    expect(effects.bassSupported, isTrue);
    expect(calls.first.arguments['sessionId'], 42);
  });

  test('Frequenz-Beschriftung wie in der Vorlage', () {
    expect(const EqBand(index: 0, centerHz: 60, level: 0).label, '60Hz');
    expect(const EqBand(index: 4, centerHz: 14000, level: 0).label, '14.0kHz');
  });

  test('Bandpegel wird auf den erlaubten Bereich begrenzt', () async {
    final effects = AudioEffects();
    await effects.attach(1);

    await effects.setBandLevel(0, 9999);

    expect(effects.bands.first.level, 1500);
    final call = calls.lastWhere((c) => c.method == 'setBandLevel');
    expect(call.arguments['level'], 1500);
  });

  test('Bass und Immersives Audio bleiben zwischen 0 und 1000', () async {
    final effects = AudioEffects();
    await effects.attach(1);

    await effects.setBass(2000);
    await effects.setVirtualizer(-5);

    expect(effects.bass, 1000);
    expect(effects.virtualizer, 0);
  });

  test('gespeicherte Werte werden beim nächsten Attach wiederhergestellt',
      () async {
    final effects = AudioEffects();
    await effects.attach(1);
    await effects.setEnabled(true);
    await effects.setBandLevel(1, 600);
    await effects.setBass(300);

    final neu = AudioEffects();
    await neu.init();
    await neu.attach(2);

    expect(neu.enabled, isTrue);
    expect(neu.bands[1].level, 600);
    expect(neu.bass, 300);
  });

  test('Gerät ohne Effekte meldet nicht verfügbar statt abzustürzen', () async {
    mockChannel(handler: (call) {
      throw PlatformException(code: 'audio_effects', message: 'nicht möglich');
    });
    final effects = AudioEffects();

    await effects.attach(1);

    expect(effects.available, isFalse);
    expect(effects.error, 'nicht möglich');
  });
}