import 'package:flutter_test/flutter_test.dart';
import 'package:pluriwave/modelos/alarma_musical.dart';

void main() {
  AlarmaMusical base({DateTime? snoozeHasta, DateTime? fechaUnica}) =>
      AlarmaMusical(
        id: 'f1',
        nombre: 'Fechas',
        hora: 7,
        minuto: 30,
        tipoProgramacion:
            fechaUnica != null
                ? TipoProgramacionAlarma.unica
                : TipoProgramacionAlarma.diaria,
        diasSemana: const [],
        fechaUnica: fechaUnica,
        snoozeHasta: snoozeHasta,
        snoozeOrigen: snoozeHasta?.subtract(const Duration(minutes: 5)),
        ultimaEjecucionGestionada: snoozeHasta?.subtract(
          const Duration(minutes: 5),
        ),
      );

  test('los instantes se serializan como UTC con offset explicito (Z)', () {
    // A local toIso8601String() carries no offset, so re-parsing it after a
    // device timezone change reinterprets the same wall fields as a
    // DIFFERENT instant (a snooze set in Madrid would shift hours after
    // landing in New York). Instants must round-trip offset-carrying.
    final snooze = DateTime(2026, 7, 13, 7, 10);
    final json = base(snoozeHasta: snooze).toJson();

    expect((json['snoozeHasta'] as String).endsWith('Z'), isTrue);
    expect((json['snoozeOrigen'] as String).endsWith('Z'), isTrue);
    expect(
      (json['ultimaEjecucionGestionada'] as String).endsWith('Z'),
      isTrue,
    );
  });

  test('el round-trip de instantes preserva el instante exacto', () {
    final snooze = DateTime(2026, 7, 13, 7, 10);
    final recuperada = AlarmaMusical.fromJson(base(snoozeHasta: snooze).toJson());

    expect(recuperada.snoozeHasta, snooze);
    expect(
      recuperada.snoozeOrigen,
      snooze.subtract(const Duration(minutes: 5)),
    );
  });

  test('los payloads legados sin offset siguen leyendose como hora local '
      '(sin migracion)', () {
    final legado = base().toJson()
      ..['snoozeHasta'] = '2026-07-13T07:10:00.000';
    final recuperada = AlarmaMusical.fromJson(legado);

    expect(recuperada.snoozeHasta, DateTime(2026, 7, 13, 7, 10));
  });

  test('fechaUnica sigue siendo fecha de pared: conserva y/m/d en local', () {
    final unica = DateTime(2026, 7, 13);
    final recuperada = AlarmaMusical.fromJson(
      base(fechaUnica: unica).toJson(),
    );

    expect(recuperada.fechaUnica!.year, 2026);
    expect(recuperada.fechaUnica!.month, 7);
    expect(recuperada.fechaUnica!.day, 13);
  });
}