#include "gtest/gtest.h"

#include <atomic>
#include <chrono>
#include <cstdlib>
#include <iostream>
#include <string>
#include <thread>
#include <vector>

#include "communication.hpp"

TEST(SystemTest, ReturnWithoutThrowing) {
  struct Master : public Reactor {
    Master(System *system, std::string name) : Reactor(system, name) {}
    virtual void Run() {
      CloseConnector("main");
    }
  };

  System system;
  ASSERT_NO_THROW(system.StartServices());
  ASSERT_NO_THROW(system.Spawn<Master>("master"));
  ASSERT_NO_THROW(system.AwaitShutdown());
}


TEST(ChannelCreationTest, ThrowOnReusingChannelName) {
  struct Master : public Reactor {
    Master(System *system, std::string name) : Reactor(system, name) {}
    virtual void Run() {
      Open("channel");
      ASSERT_THROW(Open("channel"), std::runtime_error);
      CloseConnector("main");
      CloseConnector("channel");
    }
  };

  System system;
  system.Spawn<Master>("master");
  system.AwaitShutdown();
}


TEST(ConnectorSetUpTest, CheckMainChannelIsSet) {
  struct Master : public Reactor {
    Master(System *system, std::string name) : Reactor(system, name) {}
    virtual void Run() {
      std::shared_ptr<Channel> channel;
      while (!(channel = system_->FindChannel("worker", "main")))
        std::this_thread::sleep_for(std::chrono::seconds(1));
      std::this_thread::sleep_for(std::chrono::seconds(1));
      CloseConnector("main");
    }
  };

  struct Worker : public Reactor {
    Worker(System *system, std::string name) : Reactor(system, name) {}
    virtual void Run() {
      std::shared_ptr<Channel> channel;
      while (!(channel = system_->FindChannel("master", "main")))
        std::this_thread::sleep_for(std::chrono::seconds(1));
      std::this_thread::sleep_for(std::chrono::seconds(1));
      CloseConnector("main");
    }
  };

  System system;
  system.Spawn<Master>("master");
  system.Spawn<Worker>("worker");
  system.AwaitShutdown();
}


TEST(SimpleSendTest, OneSimpleSend) {
  struct MessageInt : public Message {
    MessageInt(int xx) : x(xx) {}
    int x;
  };

  struct Master : public Reactor {
    Master(System *system, std::string name) : Reactor(system, name) {}
    virtual void Run() {
      std::shared_ptr<Channel> channel;
      while (!(channel = system_->FindChannel("worker", "main")))
        std::this_thread::sleep_for(std::chrono::seconds(1));
      channel->Send(typeid(nullptr), std::make_unique<MessageInt>(123));
      CloseConnector("main"); // Write-end doesn't need to be closed because it's in RAII.
    }
  };

  struct Worker : public Reactor {
    Worker(System *system, std::string name) : Reactor(system, name) {}
    virtual void Run() {
      EventStream* stream = main_.first;
      std::unique_ptr<Message> m_uptr = stream->AwaitEvent();
      CloseConnector("main");
      MessageInt* msg = dynamic_cast<MessageInt *>(m_uptr.get());
      ASSERT_NE(msg, nullptr);
      ASSERT_EQ(msg->x, 123);
    }
  };

  System system;
  system.Spawn<Master>("master");
  system.Spawn<Worker>("worker");
  system.AwaitShutdown();
}


TEST(SimpleSendTest, IgnoreAfterClose) {
  struct MessageInt : public Message {
    MessageInt(int xx) : x(xx) {}
    int x;
  };

  struct Master : public Reactor {
    Master(System *system, std::string name) : Reactor(system, name) {}
    virtual void Run() {
      std::shared_ptr<Channel> channel;
      while (!(channel = system_->FindChannel("worker", "main")))
        std::this_thread::sleep_for(std::chrono::seconds(1));
      channel->Send(typeid(nullptr), std::make_unique<MessageInt>(101));
      channel->Send(typeid(nullptr), std::make_unique<MessageInt>(102));
      std::this_thread::sleep_for(std::chrono::seconds(1));
      channel->Send(typeid(nullptr), std::make_unique<MessageInt>(103)); // these ones should be ignored
      channel->Send(typeid(nullptr), std::make_unique<MessageInt>(104));
      CloseConnector("main"); // Write-end doesn't need to be closed because it's in RAII.
    }
  };

  struct Worker : public Reactor {
    Worker(System *system, std::string name) : Reactor(system, name) {}
    virtual void Run() {
      EventStream* stream = main_.first;
      std::unique_ptr<Message> m_uptr = stream->AwaitEvent();
      CloseConnector("main");
      MessageInt* msg = dynamic_cast<MessageInt *>(m_uptr.get());
      ASSERT_NE(msg, nullptr);
      ASSERT_EQ(msg->x, 101);
    }
  };

  System system;
  system.Spawn<Master>("master");
  system.Spawn<Worker>("worker");
  system.AwaitShutdown();
}


TEST(SimpleSendTest, OnEvent) {
  struct MessageInt : public Message {
    MessageInt(int xx) : x(xx) {}
    int x;
  };
  struct MessageChar : public Message {
    MessageChar(char xx) : x(xx) {}
    char x;
  };


  struct Master : public Reactor {
    Master(System *system, std::string name) : Reactor(system, name) {}
    virtual void Run() {
      std::shared_ptr<Channel> channel;
      while (!(channel = system_->FindChannel("worker", "main")))
        std::this_thread::sleep_for(std::chrono::seconds(1));

      channel->Send(typeid(MessageInt), std::make_unique<MessageInt>(101));
      channel->Send(typeid(MessageChar), std::make_unique<MessageChar>('a'));
      channel->Send(typeid(MessageInt), std::make_unique<MessageInt>(103)); // these ones should be ignored
      channel->Send(typeid(MessageChar), std::make_unique<MessageChar>('b'));
      CloseConnector("main"); // Write-end doesn't need to be closed because it's in RAII.
    }
  };

  struct Worker : public Reactor {
    Worker(System *system, std::string name) : Reactor(system, name) {}

    struct EndMessage : Message {};
    int correct_vals = 0;

    virtual void Run() {
      EventStream* stream = main_.first;
      correct_vals = 0;

      stream->OnEvent(typeid(MessageInt), [this](const Message& msg, EventStream::Subscription& subscription) {
          const MessageInt& msgint = dynamic_cast<const MessageInt&>(msg);
          std::cout << "msg has int " << msgint.x << std::endl;
          ASSERT_TRUE(msgint.x == 101 || msgint.x == 103);
          ++correct_vals;
          main_.second->Send(typeid(EndMessage), std::make_unique<EndMessage>());
        });

      stream->OnEvent(typeid(MessageChar), [this](const Message& msg, EventStream::Subscription& subscription) {
          const MessageChar& msgchar = dynamic_cast<const MessageChar&>(msg);
          std::cout << "msg has char " << msgchar.x << std::endl;

          ASSERT_TRUE(msgchar.x == 'a' || msgchar.x == 'b');
          ++correct_vals;
          main_.second->Send(typeid(EndMessage), std::make_unique<EndMessage>());
        });

      stream->OnEvent(typeid(EndMessage), [this](const Message&, EventStream::Subscription&) {
          ASSERT_LE(correct_vals, 4);
          if (correct_vals == 4) {
            CloseConnector("main");
          }
        });
    }
  };

  System system;
  system.Spawn<Master>("master");
  system.Spawn<Worker>("worker");
  system.AwaitShutdown();
}





int main(int argc, char **argv) {
  ::testing::InitGoogleTest(&argc, argv);
  return RUN_ALL_TESTS();
}