/*
 * Copyright 2003-2017 The Music Player Daemon Project
 * http://www.musicpd.org
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef MPD_NEIGHBOR_ALL_HXX
#define MPD_NEIGHBOR_ALL_HXX

#include "check.h"
#include "Compiler.h"
#include "thread/Mutex.hxx"

#include <forward_list>

class EventLoop;
class NeighborExplorer;
class NeighborListener;
struct NeighborInfo;

/**
 * A class that initializes and opens all configured neighbor plugins.
 */
class NeighborGlue {
	struct Explorer {
		NeighborExplorer *const explorer;

		Explorer(NeighborExplorer *_explorer):explorer(_explorer) {}
		Explorer(const Explorer &) = delete;
		~Explorer();
	};

	Mutex mutex;

	std::forward_list<Explorer> explorers;

public:
	typedef std::forward_list<NeighborInfo> List;

	NeighborGlue() = default;
	NeighborGlue(const NeighborGlue &) = delete;
	~NeighborGlue();

	bool IsEmpty() const {
		return explorers.empty();
	}

	/**
	 * Throws std::runtime_error on error.
	 */
	void Init(EventLoop &loop, NeighborListener &listener);

	void Open();
	void Close();

	/**
	 * Get the combined list of all neighbors from all active
	 * plugins.
	 */
	gcc_pure
	List GetList() const noexcept;
};

#endif
