/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/**
 * Copyright (c) 2014-2015,  Regents of the University of California
 *
 * This file is part of ndn-group-encrypt (Group-based Encryption Protocol for NDN).
 * See AUTHORS.md for complete list of ndn-group-encrypt authors and contributors.
 *
 * ndn-group-encrypt is free software: you can redistribute it and/or modify it under the terms
 * of the GNU General Public License as published by the Free Software Foundation,
 * either version 3 of the License, or (at your option) any later version.
 *
 * ndn-group-encrypt is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 * PURPOSE.  See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * ndn-group-encrypt, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author Zhiyi Zhang <dreamerbarrychang@gmail.com>
 * @author Yingdi Yu <yingdi@cs.ucla.edu>
 */

#include "consumer.hpp"
#include "boost-test.hpp"
#include "algo/encryptor.hpp"
#include "unit-test-time-fixture.hpp"

#include <ndn-cxx/security/key-chain.hpp>
#include <ndn-cxx/util/dummy-client-face.hpp>
#include <ndn-cxx/util/time-unit-test-clock.hpp>
#include <boost/filesystem.hpp>
#include <boost/asio.hpp>

namespace ndn {
namespace gep {
namespace tests {

static const uint8_t DATA_CONTEN[] = {
  0xcb, 0xe5, 0x6a, 0x80, 0x41, 0x24, 0x58, 0x23,
  0x84, 0x14, 0x15, 0x61, 0x80, 0xb9, 0x5e, 0xbd,
  0xce, 0x32, 0xb4, 0xbe, 0xbc, 0x91, 0x31, 0xd6,
  0x19, 0x00, 0x80, 0x8b, 0xfa, 0x00, 0x05, 0x9c
};

static const uint8_t AES_KEY[] = {
  0xdd, 0x60, 0x77, 0xec, 0xa9, 0x6b, 0x23, 0x1b,
  0x40, 0x6b, 0x5a, 0xf8, 0x7d, 0x3d, 0x55, 0x32
};

static const uint8_t IV[] = {
  0x73, 0x6f, 0x6d, 0x65, 0x72, 0x61, 0x6e, 0x64,
  0x6f, 0x6d, 0x76, 0x65, 0x63, 0x74, 0x6f, 0x72
};

class ConsumerFixture : public UnitTestTimeFixture
{
public:
  ConsumerFixture()
    : tmpPath(boost::filesystem::path(TMP_TESTS_PATH))
    , face1(util::makeDummyClientFace(io, {true, true}))
    , face2(util::makeDummyClientFace(io, {true, true}))
    , readInterestOffset1(0)
    , readDataOffset1(0)
    , readInterestOffset2(0)
    , readDataOffset2(0)
    , groupName("/Prefix/READ")
    , contentName("/Prefix/SAMPLE/Content")
    , cKeyName("/Prefix/SAMPLE/Content/C-KEY/1")
    , eKeyName("/Prefix/READ/E-KEY/1/2")
    , dKeyName("/Prefix/READ/D-KEY/1/2")
    , uKeyName("/U/Key")
    , uName("/U")
  {
    boost::filesystem::create_directories(tmpPath);

    // generate e/d key
    RandomNumberGenerator rng;
    RsaKeyParams params;
    fixtureDKeyBuf = algo::Rsa::generateKey(rng, params).getKeyBits();
    fixtureEKeyBuf = algo::Rsa::deriveEncryptKey(fixtureDKeyBuf).getKeyBits();

    // generate user key
    fixtureUDKeyBuf = algo::Rsa::generateKey(rng, params).getKeyBits();
    fixtureUEKeyBuf = algo::Rsa::deriveEncryptKey(fixtureUDKeyBuf).getKeyBits();

    // load C-KEY
    fixtureCKeyBuf = Buffer(AES_KEY, sizeof(AES_KEY));
  }

  ~ConsumerFixture()
  {
    boost::filesystem::remove_all(tmpPath);
  }

  shared_ptr<Data>
  createEncryptedContent()
  {
    shared_ptr<Data> contentData = make_shared<Data>(contentName);
    algo::EncryptParams eparams(tlv::AlgorithmAesCbc);
    eparams.setIV(IV, sizeof(IV));
    algo::encryptData(*contentData, DATA_CONTEN, sizeof(DATA_CONTEN), cKeyName,
                      fixtureCKeyBuf.buf(), fixtureCKeyBuf.size(), eparams);
    keyChain.sign(*contentData);
    return contentData;
  }

  shared_ptr<Data>
  createEncryptedCKey()
  {
    shared_ptr<Data> cKeyData = make_shared<Data>(cKeyName);
    algo::EncryptParams eparams(tlv::AlgorithmRsaOaep);
    algo::encryptData(*cKeyData, fixtureCKeyBuf.buf(), fixtureCKeyBuf.size(), dKeyName,
                      fixtureEKeyBuf.buf(), fixtureEKeyBuf.size(), eparams);
    keyChain.sign(*cKeyData);
    return cKeyData;
  }

  shared_ptr<Data>
  createEncryptedDKey()
  {
    shared_ptr<Data> dKeyData = make_shared<Data>(dKeyName);
    algo::EncryptParams eparams(tlv::AlgorithmRsaOaep);
    algo::encryptData(*dKeyData, fixtureDKeyBuf.buf(), fixtureDKeyBuf.size(), uKeyName,
                      fixtureUEKeyBuf.buf(), fixtureUEKeyBuf.size(), eparams);
    keyChain.sign(*dKeyData);
    return dKeyData;
  }

  bool
  passPacket()
  {
    bool hasPassed = false;

    checkFace(face1->sentInterests, readInterestOffset1, *face2, hasPassed);
    checkFace(face1->sentDatas, readDataOffset1, *face2, hasPassed);
    checkFace(face2->sentInterests, readInterestOffset2, *face1, hasPassed);
    checkFace(face2->sentDatas, readDataOffset2, *face1, hasPassed);

    return hasPassed;
  }

  template<typename Packet>
  void
  checkFace(std::vector<Packet>& receivedPackets,
            size_t& readPacketOffset,
            util::DummyClientFace& receiver,
            bool& hasPassed)
  {
    while (receivedPackets.size() > readPacketOffset) {
      receiver.receive(receivedPackets[readPacketOffset]);
      readPacketOffset++;
      hasPassed = true;
    }
  }

public:
  boost::filesystem::path tmpPath;

  shared_ptr<util::DummyClientFace> face1;
  shared_ptr<util::DummyClientFace> face2;

  size_t readInterestOffset1;
  size_t readDataOffset1;
  size_t readInterestOffset2;
  size_t readDataOffset2;

  KeyChain keyChain;

  Buffer fixtureCKeyBuf;
  Buffer fixtureEKeyBuf;
  Buffer fixtureDKeyBuf;
  Buffer fixtureUEKeyBuf;
  Buffer fixtureUDKeyBuf;

  Name groupName;
  Name contentName;
  Name cKeyName;
  Name eKeyName;
  Name dKeyName;
  Name uKeyName;
  Name uName;
};

BOOST_FIXTURE_TEST_SUITE(TestConsumer, ConsumerFixture)

BOOST_AUTO_TEST_CASE(DecryptContent)
{
  std::string dbDir = tmpPath.c_str();
  dbDir += "/test.db";

  // generate AES key pairs
  Buffer aesKeyBuf = Buffer(AES_KEY, sizeof(AES_KEY));

  // generate C-KEY packet
  auto cKeyData = createEncryptedCKey();
  // generate Content packet
  auto contentData = createEncryptedContent();

  // create consumer
  Consumer consumer(*face1, Name("/Group"), Name("/U"), dbDir);

  // decrypt
  consumer.decrypt(cKeyData->getContent().blockFromValue(),
                   fixtureDKeyBuf,
                   [=](const Buffer& result){
                     BOOST_CHECK_EQUAL_COLLECTIONS(result.begin(), result.end(),
                                                   aesKeyBuf.begin(),
                                                   aesKeyBuf.end());
                   },
                   [=](const ErrorCode&, const std::string&){
                     BOOST_CHECK(false);
                   });

  // decrypt
  consumer.decrypt(contentData->getContent().blockFromValue(),
                   fixtureCKeyBuf,
                   [=](const Buffer& result){
                     BOOST_CHECK_EQUAL_COLLECTIONS(result.begin(), result.end(),
                                                   DATA_CONTEN,
                                                   DATA_CONTEN + sizeof(DATA_CONTEN));
                   },
                   [=](const ErrorCode&, const std::string&){
                     BOOST_CHECK(false);
                   });
}

BOOST_AUTO_TEST_CASE(Consume)
{
  auto contentData = createEncryptedContent();
  auto cKeyData = createEncryptedCKey();
  auto dKeyData = createEncryptedDKey();

  int contentCount = 0;
  int cKeyCount = 0;
  int dKeyCount = 0;

  Name prefix("/Prefix");
  // prepare face1
  face1->setInterestFilter(prefix,
                           [&] (const InterestFilter&, const Interest& i) {
                             if (i.matchesData(*contentData)) {
                               contentCount = 1;
                               face1->put(*contentData);
                               return;
                             }
                             if (i.matchesData(*cKeyData)) {
                               cKeyCount = 1;
                               face1->put(*cKeyData);
                               return;
                             }
                             if (i.matchesData(*dKeyData)) {
                               dKeyCount = 1;
                               face1->put(*dKeyData);
                               return;
                             }
                             return;
                           },
                           RegisterPrefixSuccessCallback(),
                           [] (const Name&, const std::string& e) { });

  do {
    advanceClocks(time::milliseconds(10), 20);
  } while (passPacket());

  // create consumer
  std::string dbDir = tmpPath.c_str();
  dbDir += "/test.db";
  Consumer consumer(*face2, groupName, uName, dbDir);
  consumer.addDecryptionKey(uKeyName, fixtureUDKeyBuf);

  int finalCount = 0;
  consumer.consume(contentName,
                   [&](const Data& data, const Buffer& result){
                     finalCount = 1;
                     BOOST_CHECK_EQUAL_COLLECTIONS(result.begin(), result.end(),
                                                   DATA_CONTEN,
                                                   DATA_CONTEN + sizeof(DATA_CONTEN));
                   },
                   [&](const ErrorCode& code, const std::string& str){
                     BOOST_CHECK(false);
                   });

  do {
    advanceClocks(time::milliseconds(10), 20);
  } while (passPacket());

  BOOST_CHECK_EQUAL(contentCount, 1);
  BOOST_CHECK_EQUAL(cKeyCount, 1);
  BOOST_CHECK_EQUAL(dKeyCount, 1);
  BOOST_CHECK_EQUAL(finalCount, 1);
}

BOOST_AUTO_TEST_SUITE_END()

} // namespace test
} // namespace gep
} // namespace ndn