import 'dart:typed_data';

import 'package:sodium/sodium_sumo.dart';
import 'package:test/test.dart';

/// [hex] as bytes.
Uint8List _bytes(String hex) => Uint8List.fromList([
  for (var i = 0; i < hex.length; i += 2)
    int.parse(hex.substring(i, i + 2), radix: 16),
]);

/// [bytes] in lower-case hex.
String _hex(List<int> bytes) =>
    bytes.map((byte) => byte.toRadixString(16).padLeft(2, '0')).join();

Future<void> main() async {
  final sodium = await SodiumSumoInit.init();

  // libsodium's own known answers for crypto_pwhash with Argon2id
  // (libsodium 1.0.18, test/default/pwhash_argon2id.c's tv(), vectors 0
  // and 6, and their lines 1 and 7 of pwhash_argon2id.exp): the password
  // and salt as the test cuts them (the password to its length, the salt
  // to 16 bytes), the output length, the passes and the memory.
  const vectors =
      <
        ({
          String password,
          int length,
          String salt,
          int outLen,
          int opsLimit,
          int memLimit,
          String expected,
        })
      >[
        (
          password:
              'a347ae92bce9f80f6f595a4480fc9c2fe7e7d7148d371e9487d75f5c23008ffa'
              'e065577a928febd9b1973a5a95073acdbeb6a030cfc0d79caa2dc5cd011cef02'
              'c08da232d76d52dfbca38ca8dcbd665b17d1665f7cf5fe59772ec909733b24de'
              '97d6f58d220b20c60d7c07ec1fd93c52c31020300c6c1facd77937a597c7a6',
          length: 127,
          salt: '5541fbc995d5c197ba290346d2c559de',
          outLen: 155,
          opsLimit: 5,
          memLimit: 7256678,
          expected:
              '18acec5d6507739f203d1f5d9f1d862f7c2cdac4f19d2bdff64487e60d969e3c'
              'ed615337b9eec6ac4461c6ca07f0939741e57c24d0005c7ea171a0ee1e734824'
              '9d135b38f222e4dad7b9a033ed83f5ca27277393e316582033c74affe2566a2b'
              'ea47f91f0fd9fe49ece7e1f79f3ad6e9b23e0277c8ecc4b313225748dd2a80f5'
              '679534a0700e246a79a49b3f74eb89ec6205fe1eeb941c73b1fcf1',
        ),
        (
          password:
              'b540beb016a5366524d4605156493f9874514a5aa58818cd0c6dfffaa9e90205'
              'f17b',
          length: 34,
          salt: '44071f6d181561670bda728d43fb79b4',
          outLen: 231,
          opsLimit: 1,
          memLimit: 1631659,
          expected:
              '7fb72409b0987f8190c3729710e98c3f80c5a8727d425fdcde7f3644d467fe97'
              '3f5b5fee683bd3fce812cb9ae5e9921a2d06c2f1905e4e839692f2b934b682f1'
              '1a2fe2b90482ea5dd234863516dba6f52dc0702d324ec77d860c2e181f84472b'
              'd7104fedce071ffa93c5309494ad51623d214447a7b2b1462dc7d5d55a1f6fd5'
              'b54ce024118d86f0c6489d16545aaa87b6689dad9f2fb47fda9894f8e12b87d9'
              '78b483ccd4cc5fd9595cdc7a818452f915ce2f7df95ec12b1c72e3788d473441'
              'd884f9748eb14703c21b45d82fd667b85f5b2d98c13303b3fe76285531a826b6'
              'fc0fe8e3dddecf',
        ),
      ];

  for (final (index, vector) in vectors.indexed) {
    test("Argon2id gives libsodium's known answer $index", () {
      final key = sodium.crypto.pwhash.callRaw(
        outLen: vector.outLen,
        password: Int8List.fromList(_bytes(vector.password)),
        salt: _bytes(vector.salt),
        opsLimit: vector.opsLimit,
        memLimit: vector.memLimit,
        alg: CryptoPwhashAlgorithm.argon2id13,
      );
      expect(_bytes(vector.password), hasLength(vector.length));
      expect(_hex(key.extractBytes()), vector.expected);
      key.dispose();
    });
  }
}