// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "net/quic/quic_sent_entropy_manager.h"

#include <algorithm>
#include <vector>

#include "testing/gmock/include/gmock/gmock.h"
#include "testing/gtest/include/gtest/gtest.h"

using std::make_pair;
using std::pair;
using std::vector;

namespace net {
namespace test {
namespace {

class QuicSentEntropyManagerTest : public ::testing::Test {
 protected:
  QuicSentEntropyManager entropy_manager_;
};

TEST_F(QuicSentEntropyManagerTest, SentEntropyHash) {
  EXPECT_EQ(0, entropy_manager_.EntropyHash(0));

  vector<pair<QuicPacketSequenceNumber, QuicPacketEntropyHash> > entropies;
  entropies.push_back(make_pair(1, 12));
  entropies.push_back(make_pair(2, 1));
  entropies.push_back(make_pair(3, 33));
  entropies.push_back(make_pair(4, 3));

  for (size_t i = 0; i < entropies.size(); ++i) {
    entropy_manager_.RecordPacketEntropyHash(entropies[i].first,
                                             entropies[i].second);
  }

  QuicPacketEntropyHash hash = 0;
  for (size_t i = 0; i < entropies.size(); ++i) {
    hash ^= entropies[i].second;
    EXPECT_EQ(hash, entropy_manager_.EntropyHash(i + 1));
  }
}

TEST_F(QuicSentEntropyManagerTest, IsValidEntropy) {
  QuicPacketEntropyHash entropies[10] =
      {12, 1, 33, 3, 32, 100, 28, 42, 22, 255};
  for (size_t i = 0; i < 10; ++i) {
    entropy_manager_.RecordPacketEntropyHash(i + 1, entropies[i]);
  }

  SequenceNumberSet missing_packets;
  missing_packets.insert(1);
  missing_packets.insert(4);
  missing_packets.insert(7);
  missing_packets.insert(8);

  QuicPacketEntropyHash entropy_hash = 0;
  for (size_t i = 0; i < 10; ++i) {
    if (missing_packets.find(i + 1) == missing_packets.end()) {
      entropy_hash ^= entropies[i];
    }
  }

  EXPECT_TRUE(entropy_manager_.IsValidEntropy(10, missing_packets,
                                              entropy_hash));
}

}  // namespace
}  // namespace test
}  // namespace net