import 'package:flutter_test/flutter_test.dart';
import 'package:pad_scanner/services/boxing_context.dart';

void main() {
  group('decideMultiCodePaichanContext', () {
    test('first scan records context and fills recommended box if empty', () {
      final decision = decideMultiCodePaichanContext(
        lastPaichanNo: null,
        currentPaichanNo: 'W00009',
        currentBoxNoText: '',
        maxBoxNo: 3,
      );

      expect(decision.change, PaichanContextChange.firstScan);
      expect(decision.boxNoToApply, 4);
      expect(decision.isSwitched, isFalse);
    });

    test('same paichan keeps current box number', () {
      final decision = decideMultiCodePaichanContext(
        lastPaichanNo: 'W00009',
        currentPaichanNo: 'W00009',
        currentBoxNoText: '8',
        maxBoxNo: 3,
      );

      expect(decision.change, PaichanContextChange.samePaichan);
      expect(decision.boxNoToApply, isNull);
      expect(decision.isSwitched, isFalse);
    });

    test('switched paichan resets to new paichan max box plus one', () {
      final decision = decideMultiCodePaichanContext(
        lastPaichanNo: 'W00009',
        currentPaichanNo: 'W00010',
        currentBoxNoText: '8',
        maxBoxNo: 1,
      );

      expect(decision.change, PaichanContextChange.switchedPaichan);
      expect(decision.boxNoToApply, 2);
      expect(decision.isSwitched, isTrue);
    });

    test(
      'same paichan defensively fills recommended box when box is empty',
      () {
        final decision = decideMultiCodePaichanContext(
          lastPaichanNo: 'W00009',
          currentPaichanNo: 'W00009',
          currentBoxNoText: '',
          maxBoxNo: 4,
        );

        expect(decision.change, PaichanContextChange.samePaichan);
        expect(decision.boxNoToApply, 5);
      },
    );
  });
}