import 'package:flutter/material.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:pluriwave/l10n/gen/app_localizations.dart';
import 'package:pluriwave/modelos/preset_ecualizador.dart';
import 'package:pluriwave/tema/pluriwave_tokens.dart';
import 'package:pluriwave/widgets/ecualizador_widget.dart';

/// WU13 task 13.1 — first-class regression guard (design ADR-5, spec
/// `eq-custom-presets` "Five-Band Equalizer"): the equalizer widget must
/// always render exactly 5 vertical sliders. Band count is device-reported
/// via `just_audio`'s `AndroidEqualizer` (spike, Engram id 2498), not
/// app-chosen — any future change rendering 7 sliders is rejected on sight.
///
/// **Correction found at apply time**: `tasks.md`'s WU13 Verify command
/// names this file as if it already existed ("Modified tests:
/// ecualizador_widget_test.dart"). No such file existed before this commit
/// (`ecualizador_widget.dart` had zero test coverage) — created new instead.
void main() {
  Widget buildWidget({
    PresetEcualizador? preset,
    bool habilitado = true,
    void Function(PresetEcualizador)? onCambio,
  }) {
    return MaterialApp(
      locale: const Locale('en'),
      localizationsDelegates: AppLocalizations.localizationsDelegates,
      supportedLocales: AppLocalizations.supportedLocales,
      home: Scaffold(
        body: EcualizadorWidget(
          preset: preset ?? PresetEcualizador.flat,
          habilitado: habilitado,
          onCambio: onCambio ?? (_) {},
        ),
      ),
    );
  }

  testWidgets('renders exactly 5 vertical sliders, one per band', (
    tester,
  ) async {
    await tester.pumpWidget(buildWidget());

    expect(find.byType(Slider), findsNWidgets(5));
  });

  testWidgets('renders exactly 5 sliders regardless of the preset selected', (
    tester,
  ) async {
    // Regression guard restated: a future change proposing 7 sliders (the
    // rejected mockup band count) must fail this test regardless of which
    // fixed preset is active.
    await tester.pumpWidget(buildWidget(preset: PresetEcualizador.jazz));

    expect(find.byType(Slider), findsNWidgets(5));
  });

  testWidgets('dragging a slider reports the updated band back via onCambio', (
    tester,
  ) async {
    PresetEcualizador? reportado;
    await tester.pumpWidget(buildWidget(onCambio: (p) => reportado = p));

    final slider = tester.widget<Slider>(find.byType(Slider).first);
    slider.onChanged?.call(6.0);
    await tester.pump();

    expect(reportado, isNotNull);
    expect(reportado!.bandas.length, 5);
    expect(reportado!.bandas.first, 6.0);
  });

  testWidgets(
    'habilitado: false disables every slider (greyed, non-interactive)',
    (tester) async {
      await tester.pumpWidget(buildWidget(habilitado: false));

      final sliders = tester.widgetList<Slider>(find.byType(Slider));
      expect(sliders, hasLength(5));
      for (final slider in sliders) {
        expect(slider.onChanged, isNull);
      }
    },
  );

  testWidgets('habilitado: true (default) keeps every slider interactive', (
    tester,
  ) async {
    await tester.pumpWidget(buildWidget());

    final sliders = tester.widgetList<Slider>(find.byType(Slider));
    expect(sliders, hasLength(5));
    for (final slider in sliders) {
      expect(slider.onChanged, isNotNull);
    }
  });

  // Visual-fidelity guards (audit id 2521, items 11.4 and 11.6). These two
  // values drifted silently once already: the whole point of the fidelity
  // pass was that behavioural tests ("renders 5 sliders") never noticed the
  // sliders were 46% too short and painted in the wrong colour family.
  testWidgets('each band column is 280 tall, as the prototype draws it', (
    tester,
  ) async {
    await tester.pumpWidget(buildWidget());

    final columnas = tester.widgetList<SizedBox>(
      find.descendant(
        of: find.byType(EcualizadorWidget),
        matching: find.byType(SizedBox),
      ),
    );

    expect(
      columnas.where((c) => c.height == 280),
      hasLength(5),
      reason:
          'prototype t4 line 581 sizes the band column at 280; 152 left the '
          'sliders 46% short',
    );
  });

  testWidgets('band fill uses the brand teal, not the LIVE-badge green', (
    tester,
  ) async {
    await tester.pumpWidget(buildWidget());

    final tema = SliderTheme.of(tester.element(find.byType(Slider).first));

    expect(tema.activeTrackColor, PluriWaveTokens.brand);
    expect(tema.thumbColor, PluriWaveTokens.brand);
    expect(
      tema.activeTrackColor,
      isNot(PluriWaveTokens.dark.liveGreen),
      reason:
          'liveGreen (#7EE4C2) is the LIVE badge colour; the prototype fills '
          'EQ bands with brand teal #21D4D9 (t4 line 585)',
    );
  });
}