#pragma once

#include "EpistmoolServer/Connection.hpp"

#include <QMultiHash>
#include <QObject>
#include <unordered_map>
#include <vector>

namespace Epistmool::Server {

struct SessionId {
	int index;

	static SessionId makeInvalid();
	bool isInvalid() const;

	bool operator==(const SessionId&) const = default;
};

class Session
{
	friend class SessionManager;

private:
	std::vector<ConnectionId> mConnections;
	SessionId mSessionId;

public:
	explicit Session(SessionId id);

	SessionId getSessionId() const;
	const std::vector<ConnectionId>& getConnections() const;
};

class SessionManager : public QObject
{
	Q_OBJECT

	friend class Session;

private:
	// Use this intead of QHash for 1. pointer stability 2. Session is a move-only type
	std::unordered_map<int, Session> mSessions;
	QMultiHash<int, int> mConnection2SessionMap;
	int mNextIndex;

public:
	explicit SessionManager(QObject* parent = nullptr);

	Session* findOrCreateSession(SessionId id);
	Session* findSession(SessionId id);

	void addConnection(SessionId id, ConnectionId connId);

public slots:
	void dropConnection(Epistmool::Server::ConnectionId connId);
};

} // namespace Epistmool::Server