// Copyright 2019 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "util/crypto/sha2.h"

#include <stddef.h>
#include <stdint.h>

#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "util/std_util.h"

namespace openscreen {

using testing::ElementsAreArray;

TEST(Sha256Test, Test1) {
  // Example B.1 from FIPS 180-2: one-block message.
  std::string input = "abc";
  constexpr uint8_t kExpected[] = {
      0xba, 0x78, 0x16, 0xbf, 0x8f, 0x01, 0xcf, 0xea, 0x41, 0x41, 0x40,
      0xde, 0x5d, 0xae, 0x22, 0x23, 0xb0, 0x03, 0x61, 0xa3, 0x96, 0x17,
      0x7a, 0x9c, 0xb4, 0x10, 0xff, 0x61, 0xf2, 0x00, 0x15, 0xad};

  uint8_t output[SHA256_DIGEST_LENGTH];
  EXPECT_EQ(Error::None(), SHA256HashString(input, output));
  EXPECT_THAT(output, ElementsAreArray(kExpected));
}

TEST(Sha256Test, Test1_String) {
  // Same as the above, but using the wrapper that returns a std::string.
  // Example B.1 from FIPS 180-2: one-block message.
  std::string input = "abc";
  constexpr uint8_t kExpected[] = {
      0xba, 0x78, 0x16, 0xbf, 0x8f, 0x01, 0xcf, 0xea, 0x41, 0x41, 0x40,
      0xde, 0x5d, 0xae, 0x22, 0x23, 0xb0, 0x03, 0x61, 0xa3, 0x96, 0x17,
      0x7a, 0x9c, 0xb4, 0x10, 0xff, 0x61, 0xf2, 0x00, 0x15, 0xad};

  const ErrorOr<std::string> output = SHA256HashString(input);
  EXPECT_TRUE(output.is_value());
  ASSERT_EQ(static_cast<size_t>(SHA256_DIGEST_LENGTH), output.value().size());
  EXPECT_THAT(output.value(), ElementsAreArray(kExpected));
}

TEST(Sha256Test, Test2) {
  // Example B.2 from FIPS 180-2: multi-block message.
  std::string input =
      "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq";
  constexpr uint8_t kExpected[] = {
      0x24, 0x8d, 0x6a, 0x61, 0xd2, 0x06, 0x38, 0xb8, 0xe5, 0xc0, 0x26,
      0x93, 0x0c, 0x3e, 0x60, 0x39, 0xa3, 0x3c, 0xe4, 0x59, 0x64, 0xff,
      0x21, 0x67, 0xf6, 0xec, 0xed, 0xd4, 0x19, 0xdb, 0x06, 0xc1};

  uint8_t output[SHA256_DIGEST_LENGTH];
  EXPECT_EQ(Error::None(), SHA256HashString(input, output));
  EXPECT_THAT(output, ElementsAreArray(kExpected));
}

TEST(Sha256Test, Test3) {
  // Example B.3 from FIPS 180-2: long message.
  std::string input(1000000, 'a');  // 'a' repeated a million times
  constexpr uint8_t kExpected[] = {
      0xcd, 0xc7, 0x6e, 0x5c, 0x99, 0x14, 0xfb, 0x92, 0x81, 0xa1, 0xc7,
      0xe2, 0x84, 0xd7, 0x3e, 0x67, 0xf1, 0x80, 0x9a, 0x48, 0xa4, 0x97,
      0x20, 0x0e, 0x04, 0x6d, 0x39, 0xcc, 0xc7, 0x11, 0x2c, 0xd0};

  uint8_t output[SHA256_DIGEST_LENGTH];
  EXPECT_EQ(Error::None(), SHA256HashString(input, output));
  EXPECT_THAT(output, ElementsAreArray(kExpected));
}
}  // namespace openscreen