////////////////////////////////////////////////////////////////////////////////
/// @brief test suite for CuckooFilter based index selectivity estimator
///
/// @file
///
/// DISCLAIMER
///
/// Copyright 2017 ArangoDB GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
///     http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
///
/// @author Andreas Streichardt
/// @author Copyright 2017, ArangoDB GmbH, Cologne, Germany
////////////////////////////////////////////////////////////////////////////////

#include "gtest/gtest.h"

#include "Rest/GeneralResponse.h"
#include "Rest/HttpRequest.h"
#include "SimpleHttpClient/Callbacks.h"
#include "SimpleHttpClient/Communicator.h"

#include <thread>
#include <chrono>

using namespace arangodb;
using namespace arangodb::communicator;

TEST(SimpleHttpClientCommunicatorTest, requests_are_properly_aborted) {
  Communicator communicator;

  bool callbacksCalled = false;

  communicator::Callbacks callbacks([&callbacksCalled](std::unique_ptr<GeneralResponse> response) {
    ASSERT_TRUE(false); // it should be aborted?!
    callbacksCalled = true;
  }, [&callbacksCalled](int errorCode, std::unique_ptr<GeneralResponse> response) {
    ASSERT_FALSE(response);
    ASSERT_EQ(errorCode, TRI_ERROR_COMMUNICATOR_REQUEST_ABORTED);
    callbacksCalled = true;
  });
  auto request = std::unique_ptr<HttpRequest>(HttpRequest::createHttpRequest(rest::ContentType::TEXT, "", 0, {}));
  request->setRequestType(RequestType::GET);
  communicator::Options opt;
  auto destination = std::string("http://www.example.com");
  auto newRequest = std::make_unique<communicator::NewRequest>(
    std::move(destination), 
    std::move(request), 
    callbacks, opt);

  communicator.addRequest(std::move(newRequest));
  communicator.work_once();
  communicator.abortRequests();
  while (communicator.work_once() > 0) {
    std::this_thread::sleep_for(std::chrono::microseconds(1));
  }
  ASSERT_TRUE(callbacksCalled);
}

TEST(SimpleHttpClientCommunicatorTest, requests_will_call_the_progress_callback) {
  Communicator communicator;

  communicator::Callbacks callbacks([](std::unique_ptr<GeneralResponse> response) {
  }, [](int errorCode, std::unique_ptr<GeneralResponse> response) {
  });

  auto request = std::unique_ptr<HttpRequest>(HttpRequest::createHttpRequest(rest::ContentType::TEXT, "", 0, {}));
  request->setRequestType(RequestType::GET);

  // CURL_LAST /* never use! */ HA! FOOL!
  CURLcode curlRc = CURL_LAST;
  communicator::Options opt;
  opt._curlRcFn = std::make_shared<std::function<void(CURLcode)>>([&curlRc](CURLcode rc) {
    curlRc = rc;
  });

  auto destination = std::string("http://www.example.com");
  auto newRequest = std::make_unique<communicator::NewRequest>(
    std::move(destination), 
    std::move(request), 
    callbacks, opt);

  communicator.addRequest(std::move(newRequest));
  communicator.work_once();
  communicator.abortRequests();
  while (communicator.work_once() > 0) {
    std::this_thread::sleep_for(std::chrono::microseconds(1));
  }
  ASSERT_EQ(curlRc, CURLE_ABORTED_BY_CALLBACK); // curlRcFn was called
}


class ConnectionCountTester : public ConnectionCount {
public:

  /// this allows testing of time bucket rotation
    void moveCursor() {advanceCursor();}


};// class ConnectionCountTester


TEST(SimpleHttpClientCommunicatorTest, connection_count) {
  ConnectionCountTester tester;
  int loop;

  // loop through the coverage minutes, see if minimum is consistent
  for (loop=0; loop<=ConnectionCount::eMinutesTracked; ++loop) {
    ASSERT_EQ(ConnectionCount::eMinOpenConnects, tester.newMaxConnections(0));
    tester.moveCursor();
  } // for

  // parameter to newMaxConnections() does NOT change history
  ASSERT_EQ(ConnectionCount::eMinOpenConnects+10, tester.newMaxConnections(10));
  ASSERT_EQ(ConnectionCount::eMinOpenConnects, tester.newMaxConnections(0));
  ASSERT_EQ(ConnectionCount::eMinOpenConnects+2, tester.newMaxConnections(2));
  ASSERT_EQ(ConnectionCount::eMinOpenConnects, tester.newMaxConnections(0));

  // parameter to updateMaxConnections() DOES change history if bigger
  tester.updateMaxConnections(10);
  ASSERT_EQ(10, tester.newMaxConnections(0));
  ASSERT_EQ(16, tester.newMaxConnections(6));
  tester.updateMaxConnections(7);
  ASSERT_EQ(10, tester.newMaxConnections(0));
  ASSERT_EQ(13, tester.newMaxConnections(3));

  // simulate time passing and returned max changing ... assumes 6 min history
  //  "10" is still in current minute
  ASSERT_EQ(6, ConnectionCount::eMinutesTracked);
  ASSERT_EQ(10, tester.newMaxConnections(0));
  tester.updateMaxConnections(17);
  ASSERT_EQ(17, tester.newMaxConnections(0));
  tester.moveCursor();
  tester.updateMaxConnections(13);
  ASSERT_EQ(17, tester.newMaxConnections(0));
  tester.moveCursor();
  tester.updateMaxConnections(11);
  ASSERT_EQ(17, tester.newMaxConnections(0));
  tester.moveCursor();
  tester.updateMaxConnections(9);
  ASSERT_EQ(17, tester.newMaxConnections(0));
  tester.moveCursor();
  tester.updateMaxConnections(10);
  ASSERT_EQ(17, tester.newMaxConnections(0));
  tester.moveCursor();
  tester.updateMaxConnections(7);
  ASSERT_EQ(17, tester.newMaxConnections(0));
  tester.moveCursor();

  // minute history now full ... should see sliding window now
  ASSERT_EQ(13, tester.newMaxConnections(0));
  tester.moveCursor();
  ASSERT_EQ(11, tester.newMaxConnections(0));
  tester.moveCursor();
  ASSERT_EQ(10, tester.newMaxConnections(0)); // 9 smaller than 10
  tester.moveCursor();
  ASSERT_EQ(10, tester.newMaxConnections(0));
  tester.moveCursor();
  ASSERT_EQ(7, tester.newMaxConnections(0));
  tester.moveCursor();
  ASSERT_EQ(ConnectionCount::eMinOpenConnects, tester.newMaxConnections(0));
  tester.moveCursor();
  ASSERT_EQ(ConnectionCount::eMinOpenConnects, tester.newMaxConnections(0));

}