#include <gflags/gflags.h>
#include <glog/logging.h>

#include "bolt_common.hpp"
#include "communication/bolt/v1/session.hpp"

using communication::bolt::ClientError;
using communication::bolt::Session;
using communication::bolt::SessionException;
using communication::bolt::State;
using communication::bolt::Value;

static const char *kInvalidQuery = "invalid query";
static const char *kQueryReturn42 = "RETURN 42";
static const char *kQueryEmpty = "no results";

class TestSessionData {};

class TestSession : public Session<TestInputStream, TestOutputStream> {
 public:
  using Session<TestInputStream, TestOutputStream>::TEncoder;

  TestSession(TestSessionData *data, TestInputStream *input_stream,
              TestOutputStream *output_stream)
      : Session<TestInputStream, TestOutputStream>(input_stream,
                                                   output_stream) {}

  std::vector<std::string> Interpret(
      const std::string &query,
      const std::map<std::string, Value> &params) override {
    if (query == kQueryReturn42 || query == kQueryEmpty) {
      query_ = query;
      return {"result_name"};
    } else {
      query_ = "";
      throw ClientError("client sent invalid query");
    }
  }

  std::map<std::string, Value> PullAll(TEncoder *encoder) override {
    if (query_ == kQueryReturn42) {
      encoder->MessageRecord(std::vector<Value>{Value(42)});
      return {};
    } else if (query_ == kQueryEmpty) {
      return {};
    } else {
      throw ClientError("client sent invalid query");
    }
  }

  void Abort() override {}

  bool Authenticate(const std::string &username,
                    const std::string &password) override {
    return true;
  }

 private:
  std::string query_;
};

// TODO: This could be done in fixture.
// Shortcuts for writing variable initializations in tests
#define INIT_VARS                                                    \
  TestInputStream input_stream;                                      \
  TestOutputStream output_stream;                                    \
  TestSessionData session_data;                                      \
  TestSession session(&session_data, &input_stream, &output_stream); \
  std::vector<uint8_t> &output = output_stream.output;

// Sample testdata that has correct inputs and outputs.
const uint8_t handshake_req[] = {0x60, 0x60, 0xb0, 0x17, 0x00, 0x00, 0x00,
                                 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                                 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
const uint8_t handshake_resp[] = {0x00, 0x00, 0x00, 0x01};
const uint8_t init_req[] = {
    0xb2, 0x01, 0xd0, 0x15, 0x6c, 0x69, 0x62, 0x6e, 0x65, 0x6f, 0x34,
    0x6a, 0x2d, 0x63, 0x6c, 0x69, 0x65, 0x6e, 0x74, 0x2f, 0x31, 0x2e,
    0x32, 0x2e, 0x31, 0xa3, 0x86, 0x73, 0x63, 0x68, 0x65, 0x6d, 0x65,
    0x85, 0x62, 0x61, 0x73, 0x69, 0x63, 0x89, 0x70, 0x72, 0x69, 0x6e,
    0x63, 0x69, 0x70, 0x61, 0x6c, 0x80, 0x8b, 0x63, 0x72, 0x65, 0x64,
    0x65, 0x6e, 0x74, 0x69, 0x61, 0x6c, 0x73, 0x80};
const uint8_t init_resp[] = {0x00, 0x03, 0xb1, 0x70, 0xa0, 0x00, 0x00};
const uint8_t run_req_header[] = {0xb2, 0x10, 0xd1};
const uint8_t pullall_req[] = {0xb0, 0x3f};
const uint8_t discardall_req[] = {0xb0, 0x2f};
const uint8_t reset_req[] = {0xb0, 0x0f};
const uint8_t ackfailure_req[] = {0xb0, 0x0e};
const uint8_t success_resp[] = {0x00, 0x03, 0xb1, 0x70, 0xa0, 0x00, 0x00};
const uint8_t ignored_resp[] = {0x00, 0x02, 0xb0, 0x7e, 0x00, 0x00};

// Write bolt chunk header (length)
void WriteChunkHeader(TestInputStream &input_stream, uint16_t len) {
  len = utils::HostToBigEndian(len);
  input_stream.Write(reinterpret_cast<uint8_t *>(&len), sizeof(len));
}

// Write bolt chunk tail (two zeros)
void WriteChunkTail(TestInputStream &input_stream) {
  WriteChunkHeader(input_stream, 0);
}

// Check that the server responded with a failure message.
void CheckFailureMessage(std::vector<uint8_t> &output) {
  ASSERT_GE(output.size(), 6);
  // skip the first two bytes because they are the chunk header
  ASSERT_EQ(output[2], 0xB1);  // tiny struct 1
  ASSERT_EQ(output[3], 0x7F);  // signature failure
  output.clear();
}

// Check that the server responded with a success message.
void CheckSuccessMessage(std::vector<uint8_t> &output, bool clear = true) {
  ASSERT_GE(output.size(), 6);
  // skip the first two bytes because they are the chunk header
  ASSERT_EQ(output[2], 0xB1);  // tiny struct 1
  ASSERT_EQ(output[3], 0x70);  // signature success
  if (clear) {
    output.clear();
  }
}

// Check that the server responded with a ignore message.
void CheckIgnoreMessage(std::vector<uint8_t> &output) {
  ASSERT_GE(output.size(), 6);
  // skip the first two bytes because they are the chunk header
  ASSERT_EQ(output[2], 0xB0);
  ASSERT_EQ(output[3], 0x7E);  // signature ignore
  output.clear();
}

// Execute and check a correct handshake
void ExecuteHandshake(TestInputStream &input_stream, TestSession &session,
                      std::vector<uint8_t> &output) {
  input_stream.Write(handshake_req, 20);
  session.Execute();
  ASSERT_EQ(session.state_, State::Init);
  PrintOutput(output);
  CheckOutput(output, handshake_resp, 4);
}

// Write bolt chunk and execute command
void ExecuteCommand(TestInputStream &input_stream, TestSession &session,
                    const uint8_t *data, size_t len, bool chunk = true) {
  if (chunk) WriteChunkHeader(input_stream, len);
  input_stream.Write(data, len);
  if (chunk) WriteChunkTail(input_stream);
  session.Execute();
}

// Execute and check a correct init
void ExecuteInit(TestInputStream &input_stream, TestSession &session,
                 std::vector<uint8_t> &output) {
  ExecuteCommand(input_stream, session, init_req, sizeof(init_req));
  ASSERT_EQ(session.state_, State::Idle);
  PrintOutput(output);
  CheckOutput(output, init_resp, 7);
}

// Write bolt encoded run request
void WriteRunRequest(TestInputStream &input_stream, const char *str) {
  // write chunk header
  auto len = strlen(str);
  WriteChunkHeader(input_stream, 3 + 2 + len + 1);

  // write string header
  input_stream.Write(run_req_header, 3);

  // write string length
  WriteChunkHeader(input_stream, len);

  // write string
  input_stream.Write(str, len);

  // write empty map for parameters
  input_stream.Write("\xA0", 1);  // TinyMap0

  // write chunk tail
  WriteChunkTail(input_stream);
}

TEST(BoltSession, HandshakeWrongPreamble) {
  INIT_VARS;

  // write 0x00000001 five times
  for (int i = 0; i < 5; ++i) input_stream.Write(handshake_req + 4, 4);
  ASSERT_THROW(session.Execute(), SessionException);

  ASSERT_EQ(session.state_, State::Close);
  PrintOutput(output);
  CheckFailureMessage(output);
}

TEST(BoltSession, HandshakeInTwoPackets) {
  INIT_VARS;

  input_stream.Write(handshake_req, 10);
  session.Execute();

  ASSERT_EQ(session.state_, State::Handshake);

  input_stream.Write(handshake_req + 10, 10);
  session.Execute();

  ASSERT_EQ(session.state_, State::Init);
  PrintOutput(output);
  CheckOutput(output, handshake_resp, 4);
}

TEST(BoltSession, HandshakeWriteFail) {
  INIT_VARS;
  output_stream.SetWriteSuccess(false);
  ASSERT_THROW(ExecuteCommand(input_stream, session, handshake_req,
                              sizeof(handshake_req), false),
               SessionException);

  ASSERT_EQ(session.state_, State::Close);
  ASSERT_EQ(output.size(), 0);
}

TEST(BoltSession, HandshakeOK) {
  INIT_VARS;
  ExecuteHandshake(input_stream, session, output);
}

TEST(BoltSession, InitWrongSignature) {
  INIT_VARS;
  ExecuteHandshake(input_stream, session, output);
  ASSERT_THROW(ExecuteCommand(input_stream, session, run_req_header,
                              sizeof(run_req_header)),
               SessionException);

  ASSERT_EQ(session.state_, State::Close);
  CheckFailureMessage(output);
}

TEST(BoltSession, InitWrongMarker) {
  INIT_VARS;
  ExecuteHandshake(input_stream, session, output);

  // wrong marker, good signature
  uint8_t data[2] = {0x00, init_req[1]};
  ASSERT_THROW(ExecuteCommand(input_stream, session, data, 2),
               SessionException);

  ASSERT_EQ(session.state_, State::Close);
  CheckFailureMessage(output);
}

TEST(BoltSession, InitMissingData) {
  // test lengths, they test the following situations:
  // missing header data, missing client name, missing metadata
  int len[] = {1, 2, 25};

  for (int i = 0; i < 3; ++i) {
    INIT_VARS;
    ExecuteHandshake(input_stream, session, output);
    ASSERT_THROW(ExecuteCommand(input_stream, session, init_req, len[i]),
                 SessionException);

    ASSERT_EQ(session.state_, State::Close);
    CheckFailureMessage(output);
  }
}

TEST(BoltSession, InitWriteFail) {
  INIT_VARS;
  ExecuteHandshake(input_stream, session, output);
  output_stream.SetWriteSuccess(false);
  ASSERT_THROW(
      ExecuteCommand(input_stream, session, init_req, sizeof(init_req)),
      SessionException);

  ASSERT_EQ(session.state_, State::Close);
  ASSERT_EQ(output.size(), 0);
}

TEST(BoltSession, InitOK) {
  INIT_VARS;
  ExecuteHandshake(input_stream, session, output);
  ExecuteInit(input_stream, session, output);
}

TEST(BoltSession, ExecuteRunWrongMarker) {
  INIT_VARS;

  ExecuteHandshake(input_stream, session, output);
  ExecuteInit(input_stream, session, output);

  // wrong marker, good signature
  uint8_t data[2] = {0x00, run_req_header[1]};
  ASSERT_THROW(ExecuteCommand(input_stream, session, data, sizeof(data)),
               SessionException);

  ASSERT_EQ(session.state_, State::Close);
  CheckFailureMessage(output);
}

TEST(BoltSession, ExecuteRunMissingData) {
  // test lengths, they test the following situations:
  // missing header data, missing query data, missing parameters
  int len[] = {1, 2, 37};

  for (int i = 0; i < 3; ++i) {
    INIT_VARS;
    ExecuteHandshake(input_stream, session, output);
    ExecuteInit(input_stream, session, output);
    ASSERT_THROW(ExecuteCommand(input_stream, session, run_req_header, len[i]),
                 SessionException);

    ASSERT_EQ(session.state_, State::Close);
    CheckFailureMessage(output);
  }
}

TEST(BoltSession, ExecuteRunBasicException) {
  // first test with socket write success, then with socket write fail
  for (int i = 0; i < 2; ++i) {
    INIT_VARS;

    ExecuteHandshake(input_stream, session, output);
    ExecuteInit(input_stream, session, output);

    output_stream.SetWriteSuccess(i == 0);
    WriteRunRequest(input_stream, kInvalidQuery);
    if (i == 0) {
      session.Execute();
    } else {
      ASSERT_THROW(session.Execute(), SessionException);
    }

    if (i == 0) {
      ASSERT_EQ(session.state_, State::Error);
      CheckFailureMessage(output);
    } else {
      ASSERT_EQ(session.state_, State::Close);
      ASSERT_EQ(output.size(), 0);
    }
  }
}

TEST(BoltSession, ExecuteRunWithoutPullAll) {
  INIT_VARS;

  ExecuteHandshake(input_stream, session, output);
  ExecuteInit(input_stream, session, output);

  WriteRunRequest(input_stream, kQueryReturn42);
  session.Execute();

  ASSERT_EQ(session.state_, State::Result);
}

TEST(BoltSession, ExecutePullAllDiscardAllResetWrongMarker) {
  // This test first tests PULL_ALL then DISCARD_ALL and then RESET
  // It tests for missing data in the message header
  const uint8_t *dataset[3] = {pullall_req, discardall_req, reset_req};

  for (int i = 0; i < 3; ++i) {
    INIT_VARS;

    ExecuteHandshake(input_stream, session, output);
    ExecuteInit(input_stream, session, output);

    // wrong marker, good signature
    uint8_t data[2] = {0x00, dataset[i][1]};
    ASSERT_THROW(ExecuteCommand(input_stream, session, data, sizeof(data)),
                 SessionException);

    ASSERT_EQ(session.state_, State::Close);
    CheckFailureMessage(output);
  }
}

TEST(BoltSession, ExecutePullAllBufferEmpty) {
  // first test with socket write success, then with socket write fail
  for (int i = 0; i < 2; ++i) {
    INIT_VARS;

    ExecuteHandshake(input_stream, session, output);
    ExecuteInit(input_stream, session, output);

    output_stream.SetWriteSuccess(i == 0);
    ASSERT_THROW(
        ExecuteCommand(input_stream, session, pullall_req, sizeof(pullall_req)),
        SessionException);

    ASSERT_EQ(session.state_, State::Close);
    if (i == 0) {
      CheckFailureMessage(output);
    } else {
      ASSERT_EQ(output.size(), 0);
    }
  }
}

TEST(BoltSession, ExecutePullAllDiscardAllReset) {
  // This test first tests PULL_ALL then DISCARD_ALL and then RESET
  // It tests a good message
  const uint8_t *dataset[3] = {pullall_req, discardall_req, reset_req};

  for (int i = 0; i < 3; ++i) {
    // first test with socket write success, then with socket write fail
    for (int j = 0; j < 2; ++j) {
      INIT_VARS;

      ExecuteHandshake(input_stream, session, output);
      ExecuteInit(input_stream, session, output);
      WriteRunRequest(input_stream, kQueryReturn42);
      session.Execute();

      if (j == 1) output.clear();

      output_stream.SetWriteSuccess(j == 0);
      if (j == 0) {
        ExecuteCommand(input_stream, session, dataset[i], 2);
      } else {
        ASSERT_THROW(ExecuteCommand(input_stream, session, dataset[i], 2),
                     SessionException);
      }

      if (j == 0) {
        ASSERT_EQ(session.state_, State::Idle);
        ASSERT_FALSE(session.encoder_buffer_.HasData());
        PrintOutput(output);
      } else {
        ASSERT_EQ(session.state_, State::Close);
        ASSERT_EQ(output.size(), 0);
      }
    }
  }
}

TEST(BoltSession, ExecuteInvalidMessage) {
  INIT_VARS;

  ExecuteHandshake(input_stream, session, output);
  ExecuteInit(input_stream, session, output);
  ASSERT_THROW(
      ExecuteCommand(input_stream, session, init_req, sizeof(init_req)),
      SessionException);

  ASSERT_EQ(session.state_, State::Close);
  CheckFailureMessage(output);
}

TEST(BoltSession, ErrorIgnoreMessage) {
  // first test with socket write success, then with socket write fail
  for (int i = 0; i < 2; ++i) {
    INIT_VARS;

    ExecuteHandshake(input_stream, session, output);
    ExecuteInit(input_stream, session, output);

    WriteRunRequest(input_stream, kInvalidQuery);
    session.Execute();

    output.clear();

    output_stream.SetWriteSuccess(i == 0);
    if (i == 0) {
      ExecuteCommand(input_stream, session, init_req, sizeof(init_req));
    } else {
      ASSERT_THROW(
          ExecuteCommand(input_stream, session, init_req, sizeof(init_req)),
          SessionException);
    }

    // assert that all data from the init message was cleaned up
    ASSERT_EQ(session.decoder_buffer_.Size(), 0);

    if (i == 0) {
      ASSERT_EQ(session.state_, State::Error);
      CheckOutput(output, ignored_resp, sizeof(ignored_resp));
    } else {
      ASSERT_EQ(session.state_, State::Close);
      ASSERT_EQ(output.size(), 0);
    }
  }
}

TEST(BoltSession, ErrorRunAfterRun) {
  // first test with socket write success, then with socket write fail
  INIT_VARS;

  ExecuteHandshake(input_stream, session, output);
  ExecuteInit(input_stream, session, output);

  WriteRunRequest(input_stream, kQueryReturn42);
  session.Execute();

  output.clear();

  output_stream.SetWriteSuccess(true);

  // Session holds results of last run.
  ASSERT_EQ(session.state_, State::Result);

  // New run request.
  WriteRunRequest(input_stream, kQueryReturn42);
  ASSERT_THROW(session.Execute(), SessionException);

  ASSERT_EQ(session.state_, State::Close);
}

TEST(BoltSession, ErrorCantCleanup) {
  INIT_VARS;

  ExecuteHandshake(input_stream, session, output);
  ExecuteInit(input_stream, session, output);

  WriteRunRequest(input_stream, kInvalidQuery);
  session.Execute();

  output.clear();

  // there is data missing in the request, cleanup should fail
  ASSERT_THROW(
      ExecuteCommand(input_stream, session, init_req, sizeof(init_req) - 10),
      SessionException);

  ASSERT_EQ(session.state_, State::Close);
  CheckFailureMessage(output);
}

TEST(BoltSession, ErrorWrongMarker) {
  INIT_VARS;

  ExecuteHandshake(input_stream, session, output);
  ExecuteInit(input_stream, session, output);

  WriteRunRequest(input_stream, kInvalidQuery);
  session.Execute();

  output.clear();

  // wrong marker, good signature
  uint8_t data[2] = {0x00, init_req[1]};
  ASSERT_THROW(ExecuteCommand(input_stream, session, data, sizeof(data)),
               SessionException);

  ASSERT_EQ(session.state_, State::Close);
  CheckFailureMessage(output);
}

TEST(BoltSession, ErrorOK) {
  // test ACK_FAILURE and RESET
  const uint8_t *dataset[] = {ackfailure_req, reset_req};

  for (int i = 0; i < 2; ++i) {
    // first test with socket write success, then with socket write fail
    for (int j = 0; j < 2; ++j) {
      INIT_VARS;

      ExecuteHandshake(input_stream, session, output);
      ExecuteInit(input_stream, session, output);

      WriteRunRequest(input_stream, kInvalidQuery);
      session.Execute();

      output.clear();

      output_stream.SetWriteSuccess(j == 0);
      if (j == 0) {
        ExecuteCommand(input_stream, session, dataset[i], 2);
      } else {
        ASSERT_THROW(ExecuteCommand(input_stream, session, dataset[i], 2),
                     SessionException);
      }

      // assert that all data from the init message was cleaned up
      ASSERT_EQ(session.decoder_buffer_.Size(), 0);

      if (j == 0) {
        ASSERT_EQ(session.state_, State::Idle);
        CheckOutput(output, success_resp, sizeof(success_resp));
      } else {
        ASSERT_EQ(session.state_, State::Close);
        ASSERT_EQ(output.size(), 0);
      }
    }
  }
}

TEST(BoltSession, ErrorMissingData) {
  INIT_VARS;

  ExecuteHandshake(input_stream, session, output);
  ExecuteInit(input_stream, session, output);

  WriteRunRequest(input_stream, kInvalidQuery);
  session.Execute();

  output.clear();

  // some marker, missing signature
  uint8_t data[1] = {0x00};
  ASSERT_THROW(ExecuteCommand(input_stream, session, data, sizeof(data)),
               SessionException);

  ASSERT_EQ(session.state_, State::Close);
  CheckFailureMessage(output);
}

TEST(BoltSession, MultipleChunksInOneExecute) {
  INIT_VARS;

  ExecuteHandshake(input_stream, session, output);
  ExecuteInit(input_stream, session, output);

  WriteRunRequest(input_stream, kQueryReturn42);
  ExecuteCommand(input_stream, session, pullall_req, sizeof(pullall_req));

  ASSERT_EQ(session.state_, State::Idle);
  PrintOutput(output);

  // Count chunks in output
  int len, num = 0;
  while (output.size() > 0) {
    len = (output[0] << 8) + output[1];
    output.erase(output.begin(), output.begin() + len + 4);
    ++num;
  }

  // there should be 3 chunks in the output
  // the first is a success with the query headers
  // the second is a record message
  // and the last is a success message with query run metadata
  ASSERT_EQ(num, 3);
}

TEST(BoltSession, PartialChunk) {
  INIT_VARS;
  ExecuteHandshake(input_stream, session, output);
  ExecuteInit(input_stream, session, output);

  WriteChunkHeader(input_stream, sizeof(discardall_req));
  input_stream.Write(discardall_req, sizeof(discardall_req));

  // missing chunk tail
  session.Execute();

  ASSERT_EQ(session.state_, State::Idle);
  ASSERT_EQ(output.size(), 0);

  WriteChunkTail(input_stream);

  ASSERT_THROW(session.Execute(), SessionException);

  ASSERT_EQ(session.state_, State::Close);
  ASSERT_GT(output.size(), 0);
  PrintOutput(output);
}

int main(int argc, char **argv) {
  google::InitGoogleLogging(argv[0]);
  ::testing::InitGoogleTest(&argc, argv);
  return RUN_ALL_TESTS();
}