import 'package:flutter_test/flutter_test.dart';

import 'arb_test_helpers.dart';

/// WU18 task 18.1 / 18.2 -- ARB key-parity guard.
///
/// `l10n.yaml` sets `template-arb-file: app_es.arb`, so Spanish is the l10n
/// template: any key missing from a locale's ARB silently falls back to the
/// Spanish value at runtime (not English, which is the more common
/// assumption). This test guarantees all 13 locales carry the same key set,
/// so nothing can silently render in Spanish because a locale was never
/// given that key.
void main() {
  test('all 13 ARB files declare an identical key set', () {
    final arbs = {
      for (final locale in supportedArbLocales) locale: readArb(locale),
    };
    final templateKeys = realKeys(arbs['es']!);

    for (final locale in supportedArbLocales) {
      if (locale == 'es') continue;
      final keys = realKeys(arbs[locale]!);
      final missing = templateKeys.difference(keys);
      final extra = keys.difference(templateKeys);

      expect(
        missing,
        isEmpty,
        reason:
            'app_$locale.arb is missing ${missing.length} key(s) present in '
            'the es template (these silently fall back to Spanish at '
            'runtime): $missing',
      );
      expect(
        extra,
        isEmpty,
        reason:
            'app_$locale.arb has ${extra.length} key(s) not present in the '
            'es template: $extra',
      );
    }
  });

  test('navHome exists as a key in all 13 locales', () {
    for (final locale in supportedArbLocales) {
      final arb = readArb(locale);
      expect(
        realKeys(arb).contains('navHome'),
        isTrue,
        reason: 'app_$locale.arb is missing the navHome key',
      );
    }
  });
}