// The security area on the VM and compiled to JavaScript: the part of the
// vectors of Go that test/vectors/security_vectors.g.dart holds, which
// tool/security_go_vectors.go writes with package capsule of the reference,
// and what the API does: the boundary with the reader of CMS of alg 2 and
// seal_type 2, an evaluation that never throws, and the context that the
// opening builds.
library;

import 'dart:convert';
import 'dart:math';
import 'dart:typed_data';

import 'package:datekeys/datekeys.dart';
import 'package:test/test.dart';

import 'open_vectors_support.dart';
import 'security_support.dart';
import 'vectors/security_vectors.g.dart';

final Json _vectors = jsonDecode(securityVectorsJson) as Json;

List<Json> _section(String name) => (_vectors[name]! as List).cast<Json>();

/// A reader of CMS that answers what it is given, and records its calls.
final class FakeCms implements CmsEvaluator {
  FakeCms({this.signature, this.seal, this.throws = false});

  final CmsSignatureVerdict? Function()? signature;
  final CmsSealVerdict Function()? seal;
  final bool throws;
  final calls = <String>[];
  Uint8List? signedWith;
  bool? hasSeal;

  @override
  CmsSignatureVerdict? evaluateSignature(
    Uint8List signers,
    Uint8List value,
    bool hasSeal,
    SecurityContext context,
  ) {
    calls.add('signature');
    this.hasSeal = hasSeal;
    if (throws) throw StateError('broken');
    return signature!();
  }

  @override
  CmsSealVerdict evaluateSeal(
    Uint8List token,
    Uint8List? signature,
    SecurityContext context,
  ) {
    calls.add('seal');
    signedWith = signature;
    if (throws) throw StateError('broken');
    return seal!();
  }
}

void main() {
  test('the part of the vectors is of this spec, from its generator', () {
    expect(_vectors['spec'], specVersion);
    expect(_vectors['generator'], 'tool/security_go_vectors.go');
    expect(_section('evaluate'), hasLength(greaterThan(150)));
  });

  test('the commitments, as Go builds them', () {
    expect(commitmentDifferences(_vectors['commitments']! as Json), isEmpty);
  });

  test('the encoders, as Go writes them', () {
    expect(encodeDifferences(_section('encode')), isEmpty);
    expect(encodeSecurity(), hasLength(22));
  });

  test('every eighth evaluation, with the verdicts and lines of Go', () {
    final contexts = contextsOf(_vectors);
    final texts = (_vectors['texts']! as List).cast<String>();
    final bases = [
      for (final b in (_vectors['bases']! as List).cast<String>()) fromHex(b),
    ];
    for (final c in _section('evaluate')) {
      final security = securityOf(c, bases);
      expect(
        evaluateDifferences(c, security, contexts, texts),
        isEmpty,
        reason: canonical(c),
      );
    }
  });

  test('the lines and the earliest seal of every verdict and detail', () {
    for (final c in _section('lines')) {
      expect(lineDifferences(c), isEmpty, reason: str(c, 'name'));
    }
  });

  test('the name of a certificate, as holderText of Go', () {
    final cases = _section('holder');
    expect(cases, hasLength(greaterThan(200)));
    for (final c in cases) {
      expect(
        holderText(nameOf(c), fromHex(str(c, 'hash'))),
        c['result'],
        reason: canonical(c),
      );
    }
    // A hash that is not a SHA-256 is an error of the caller.
    expect(() => holderText('Ana', Uint8List(31)), throwsArgumentError);
  });

  group('the reader of CMS', () {
    final context = SecurityContext(
      controlCommit: Uint8List(32)..[0] = 1,
      headDigest: Uint8List(32)..[0] = 2,
      roundTime: parseRfc3339('2030-01-01T00:00:00Z'),
    );
    final alg2 = encodeAuthorSignature(algCms, [0x80], [1, 2, 3]);
    final seal2 = encodeSeal(sealTypeRfc3161, [4, 5, 6]);
    final ana = SignerLine(
      holder: 'Ana',
      issuer: 'CA',
      result: SignerResult.valid,
      sealHolder: 'TSA',
      sealTime: parseRfc3339('2026-09-30T12:00:00.5Z'),
      before: true,
    );
    final tsaTime = parseRfc3339('2026-09-29T10:00:00Z');

    test('is cmsReader by default, and the opening evaluates with it', () {
      // SIGNERS empty is F1, and a token that is not DER, S2.
      final v = evaluateSecurity(
        encodeSecurityWith(signature: alg2, seal: seal2),
        context: context,
      );
      expect(
        [v.signature, v.seal, v.evaluated],
        [Verdict.signatureUnchecked, Verdict.sealUnreadable, true],
      );
      expect(v.lines, [
        Verdict.signatureUnchecked.text,
        Verdict.sealUnreadable.text,
      ]);
    });

    test('without one, alg 2 and seal_type 2 are not evaluated', () {
      final v = evaluateSecurity(
        encodeSecurityWith(signature: alg2, seal: seal2),
        context: context,
        cms: null,
      );
      expect(
        [v.signature, v.seal, v.evaluated, v.lines],
        [null, null, false, isEmpty],
      );
      final s = evaluateSecurity(
        encodeSecurityWith(signature: alg2, seal: encodeSeal(1, [1])),
        context: context,
        cms: null,
      );
      expect(
        [s.signature, s.seal, s.lines],
        [
          null,
          Verdict.sealUnsupported,
          [Verdict.sealUnsupported.text],
        ],
      );
      final f = evaluateSecurity(
        encodeSecurityWith(
          signature: encodeAuthorSignature(9, [], []),
          seal: seal2,
        ),
        context: context,
        cms: null,
      );
      expect(
        [f.signature, f.seal, f.lines],
        [
          Verdict.signatureUnchecked,
          null,
          [Verdict.signatureUnchecked.text],
        ],
      );
      expect('$f', 'Verdicts(F1, not evaluated)');
    });

    test('without a context it is never asked, as a reader of v0.10', () {
      final cms = FakeCms();
      final v = evaluateSecurity(
        encodeSecurityWith(signature: alg2, seal: seal2),
        cms: cms,
      );
      expect(
        [v.signature, v.seal],
        [Verdict.signatureUnchecked, Verdict.sealUnsupported],
      );
      expect(cms.calls, isEmpty);
    });

    test('gives F2, F5 or F6 with the signers, and the seal with its '
        'authority, in one detail', () {
      final cms = FakeCms(
        signature: () =>
            CmsSignatureVerdict(Verdict.signedComplete, Detail(signers: [ana])),
        seal: () =>
            CmsSealVerdict(Verdict.sealed, holder: 'TSA 2', time: tsaTime),
      );
      final security = encodeSecurityWith(signature: alg2, seal: seal2);
      final v = evaluateSecurity(security, context: context, cms: cms);
      expect([v.signature, v.seal], [Verdict.signedComplete, Verdict.sealed]);
      expect(cms.calls, ['signature', 'seal']);
      expect([cms.hasSeal, cms.signedWith], [true, alg2]);
      expect(v.detail!.signers, [ana]);
      expect([v.detail!.sealHolder, v.detail!.sealTime], ['TSA 2', tsaTime]);
      // The lines are those of these verdicts, which the vectors of Go
      // check: those of F6 with its signer, and S4 with its authority.
      final merged = Verdicts(
        signature: Verdict.signedComplete,
        seal: Verdict.sealed,
        detail: Detail(signers: [ana], sealHolder: 'TSA 2', sealTime: tsaTime),
      );
      expect(v.lines, merged.lines);
      expect(v.lines, hasLength(4));
      expect(v.sealedAt, tsaTime);
      // A seal without a signature seals SIG_PART 0x00.
      final alone = evaluateSecurity(
        encodeSecurityWith(seal: seal2),
        context: context,
        cms: cms,
      );
      expect(
        [alone.signature, alone.seal, cms.signedWith],
        [Verdict.noSignature, Verdict.sealed, null],
      );
    });

    test('null is F1, and S1 to S3 name no authority', () {
      final cms = FakeCms(
        signature: () => null,
        seal: () =>
            CmsSealVerdict(Verdict.sealInvalid, holder: 'x', time: tsaTime),
      );
      final v = evaluateSecurity(
        encodeSecurityWith(signature: alg2, seal: seal2),
        context: context,
        cms: cms,
      );
      expect(
        [v.signature, v.seal, v.detail],
        [Verdict.signatureUnchecked, Verdict.sealInvalid, null],
      );
    });

    test('what it throws, or a verdict out of its range, fails its own part '
        'only, as a panic in Go', () {
      final security = encodeSecurityWith(signature: alg2, seal: seal2);
      final broken = evaluateSecurity(
        security,
        context: context,
        cms: FakeCms(throws: true),
      );
      expect(
        [broken.signature, broken.seal, broken.detail],
        [Verdict.signatureUnchecked, Verdict.sealUnreadable, null],
      );
      for (final (sig, seal) in [
        (
          () => CmsSignatureVerdict(Verdict.signedSaved, Detail()),
          () => const CmsSealVerdict(Verdict.noSeal),
        ),
        (
          () => CmsSignatureVerdict(Verdict.unreadable, Detail()),
          () => const CmsSealVerdict(Verdict.sealed, holder: 'no time'),
        ),
      ]) {
        final v = evaluateSecurity(
          security,
          context: context,
          cms: FakeCms(signature: sig, seal: seal),
        );
        expect(
          [v.signature, v.seal, v.detail],
          [Verdict.signatureUnchecked, Verdict.sealUnreadable, null],
        );
      }
      // The seal fails, and the signers of the signature stay.
      final half = evaluateSecurity(
        security,
        context: context,
        cms: FakeCms(
          signature: () => CmsSignatureVerdict(
            Verdict.signedIncomplete,
            Detail(signers: [ana]),
          ),
          seal: () => throw StateError('broken'),
        ),
      );
      expect(
        [half.signature, half.seal],
        [Verdict.signedIncomplete, Verdict.sealUnreadable],
      );
      expect(
        [half.detail!.signers, half.detail!.sealTime],
        [
          [ana],
          null,
        ],
      );
    });
  });

  test('never throws, whatever the area holds', () {
    final r = Random(20261005);
    final valid = encodeSecurityWith(
      signature: encodeAuthorSignature(1, Uint8List(32), Uint8List(64)),
      seal: encodeSeal(1, [1]),
    );
    final context = SecurityContext(
      controlCommit: Uint8List(32),
      headDigest: Uint8List(32),
    );
    for (var i = 0; i < 300; i++) {
      final b = Uint8List.fromList(valid);
      for (var j = 0; j < 1 + r.nextInt(3); j++) {
        b[r.nextInt(b.length)] = r.nextInt(256);
      }
      final cut = Uint8List.sublistView(b, 0, r.nextInt(b.length + 1));
      for (final area in [
        b,
        cut,
        Uint8List.fromList(List.generate(r.nextInt(40), (_) => r.nextInt(256))),
      ]) {
        for (final ctx in [null, context]) {
          final v = evaluateSecurity(area, context: ctx);
          expect(v.evaluated, isTrue);
          expect(v.lines, isNotEmpty);
        }
      }
    }
  });

  test('the context of the opening: control_commit, head_digest, the round '
      'time and the keys', () {
    final built =
        ((_vectors['commitments']! as Json)['control_commit']! as List)
            .cast<Json>()
            .firstWhere((c) => c['decode_format'] == 3 && c['format'] == 3);
    final control = decodeControl(
      fromHex(str(built, 'control')),
      CapsuleFormat.format3,
    );
    final head = Uint8List.fromList(utf8.encode('a head'));
    final keys = {'dkauthor1x': 'Ana'};
    final input = SecurityInput(
      security: encodeSecurity(),
      head: head,
      control: control,
      format: CapsuleFormat.format3,
      roundTime: parseRfc3339('2030-01-01T00:00:00Z'),
      authorKeys: keys,
    );
    final c = securityContext(input);
    expect(toHex(c.controlCommit), built['commit']);
    expect(c.headDigest, headDigest(head));
    expect([c.roundTime, c.authorKeys], [input.roundTime, keys]);
    expect(
      [
        evaluateSecurityInput(input).signature,
        evaluateSecurityInput(input).seal,
      ],
      [Verdict.noSignature, Verdict.noSeal],
    );
    // A control that CONTROL_SIG cannot hold leaves control_commit at zero,
    // as in Go.
    final odd = securityContext(
      SecurityInput(
        security: input.security,
        head: head,
        control: control,
        format: CapsuleFormat.format1,
        roundTime: input.roundTime,
        authorKeys: const {},
      ),
    );
    expect(odd.controlCommit, Uint8List(32));
  });

  test('the texts of the verdicts and of the results', () {
    // S0 shows nothing, and the verdicts that name a key, a holder or a
    // time have their text in the lines.
    for (final v in Verdict.values) {
      expect(v.text.isEmpty, {'S0', 'F3', 'F4', 'F6', 'S4'}.contains(v.code));
    }
    for (final r in SignerResult.values) {
      expect(SignerResult.fromCode(r.code), r);
    }
    expect(SignerResult.fromCode('valida'), isNull);
    expect(Verdicts.notEvaluated.lines, isEmpty);
    expect(Verdicts.failed(StateError('x')).lines, isEmpty);
  });
}