#include <MWSessionI.h>
#include <MWUtils.h>

using namespace std;

class SessionCallbackAdapter : public MWMapCallbackAdapter,
                               public enable_shared_from_this<SessionCallbackAdapter>
{
public:
  
  SessionCallbackAdapter(const shared_ptr<MW::MWRoomCallbackPrx>& callback,
			 const shared_ptr<MW::MWSessionPrx>& session,
			 bool trace, const shared_ptr<Ice::Logger>& logger, const std::string& name) :
    _callback(callback),
    _session(session),
    _trace(trace),
    _logger(logger),
    _name(name)
  {
  }
  
  void init(Ice::StringSeq users) override
  {
    auto self = shared_from_this();
    try
      {
	_callback->initAsync(users, nullptr, [self](std::exception_ptr eptr) { self->failed(eptr); });
      }
    catch(const Ice::CommunicatorDestroyedException&)
      {
	// Ignored server is being shutdown
      }
  }
  
  void join(const shared_ptr<MW::UserJoinedEvent>& e) override
  {
    auto self = shared_from_this();
    try
      {
	_callback->joinAsync(e->timestamp, e->name, nullptr, [self](exception_ptr eptr) { self->failed(eptr); });
      }
    catch(const Ice::CommunicatorDestroyedException&)
      {
	// Ignored server is being shutdown
      }
  }
  
  void leave(const shared_ptr<MW::UserLeftEvent>& e) override
  {
    auto self = shared_from_this();
    try
      {
	_callback->leaveAsync(e->timestamp, e->name, nullptr, [self](exception_ptr eptr) { self->failed(eptr); });
      }
    catch(const Ice::CommunicatorDestroyedException&)
      {
	// Ignored server is being shutdown
      }
  }

  void send(const shared_ptr<MW::MessageEvent>& e) override
  {
    auto self = shared_from_this();
    try
      {
	_callback->sendAsync(e->timestamp, e->name, e->message, nullptr, [self](exception_ptr eptr) { self->failed(eptr); });
      }
    catch(const Ice::CommunicatorDestroyedException&)
      {
	// Ignored server is being shutdown
      }
  }
  
  void failed(exception_ptr)
  {
    if(_trace)
      {
	Ice::Trace out(_logger, "info");
	out << "Error sending request to user '" << _name << "'. The user's session will be destroyed.";
      }
    try
      {
	_session->ice_endpoints(Ice::EndpointSeq())->destroy(); // Collocated call.
      }
    catch(const Ice::LocalException&)
      {
      }
  }
  
private:

  const shared_ptr<MW::MWMapCallbackPrx> _callback;
  const shared_ptr<MW::MWSessionPrx> _session;
  const bool _trace;
  const shared_ptr<Ice::Logger> _logger;
  const string _name;
};

MWSessionI::MWSessionI(const shared_ptr<MWMap>& MWMap, const string& name, bool trace, const shared_ptr<Ice::Logger>& logger) :
  _MWMap(MWMap),
  _name(name),
  _trace(trace),
  _logger(logger)
{
}

void
MWSessionI::setCallback(shared_ptr<MW::MWMapCallbackPrx> callback, const Ice::Current& current)
{
  lock_guard<mutex> sync(_mutex);
  if(_destroy)
    {
      if(_trace)
        {
	  Ice::Trace out(_logger, "info");
	  out << "User '" << _name << "' tried to set the session callback but the session is already destroyed.";
        }
      throw Ice::ObjectNotExistException(__FILE__, __LINE__);
    }
  
  if(_callback || !callback)
    {
      return;
    }
  
  Ice::Context ctx;
  ctx["_fwd"] = "o";
  _callback = make_shared<SessionCallbackAdapter>(
						  callback->ice_context(ctx),
						  Ice::uncheckedCast<MW::MWSessionPrx>(current.adapter->createProxy(current.id)),
						  _trace, _logger, _name);
  _MWRoom->join(_name, _callback);
}

long long
MWSessionI::send(string message, const Ice::Current&)
{
  lock_guard<mutex> sync(_mutex);
  if(_destroy)
    {
      if(_trace)
        {
	  Ice::Trace out(_logger, "info");
	  out << "User '" << _name << "' tried to send a message but the session is already destroyed.";
        }
      throw Ice::ObjectNotExistException(__FILE__, __LINE__);
    }
  if(!_callback)
    {
      if(_trace)
        {
	  Ice::Trace out(_logger, "info");
	  out << "User '" << _name << "' tried to send a message without setting the callback.";
        }
      throw MW::InvalidMessageException("You cannot send messages until you join the MW Map.");
    }
  string msg;
  try
    {
      msg = validateMessage(message);
    }
  catch(const exception& ex)
    {
      if(_trace)
        {
	  Ice::Trace out(_logger, "info");
	  out << "User '" << _name << "' sent an invalid message:\n" << ex;
        }
      throw MW::InvalidMessageException(ex.what());
    }
  return _MWMap->send(_name, move(msg));
}

void
MWSessionI::destroy(const Ice::Current& current)
{
  lock_guard<mutex> sync(_mutex);
  if(_destroy)
    {
      if(_trace)
        {
	  Ice::Trace out(_logger, "info");
	  out << "Trying to destroy the session for user '" << _name << "' but the session is already destroyed.";
        }
      throw Ice::ObjectNotExistException(__FILE__, __LINE__);
    }
  try
    {
      current.adapter->remove(current.id);
      if(_callback)
        {
	  _MWMap->leave(_name);
        }
      else
        {
	  _MWMap->unreserve(_name);
        }
    }
  catch(const Ice::ObjectAdapterDeactivatedException&)
    {
      // No need to clean up, the server is shutting down.
    }
  if(_trace)
    {
      Ice::Trace out(_logger, "info");
      out << "Push session for user '" << _name << "' destroyed.";
    }
  _destroy = true;
}