/*
 Copyright (C) 2018 Erik Ogenvik

 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#ifndef CYPHESIS_ASSETSMANAGER_H
#define CYPHESIS_ASSETSMANAGER_H


#include "Singleton.h"
#include <list>
#include <map>
#include <filesystem>

class FileSystemObserver;

/**
 * Observes a series of paths. By calling "observeFile" and "observeDirectory" you can then install callbacks for when files are changed.
 */
class AssetsManager : public Singleton<AssetsManager> {
public:

	explicit AssetsManager(std::unique_ptr<FileSystemObserver> file_system_observer);

	~AssetsManager() override;

	/**
	 * Tell the assets manager to observe the "assets" directory, which contains all assets that we serve to the clients.
	 */
	void observeAssetsDirectory();

	void observeFile(std::filesystem::path path, const std::function<void(const std::filesystem::path& path)>& callback);

	void observeDirectory(std::filesystem::path path, const std::function<void(const std::filesystem::path& path)>& callback);

	std::filesystem::path getAssetsPath() const { return mAssetsPath; }

	void stopFileObserver();

private:

	std::unique_ptr<FileSystemObserver> m_file_system_observer;

	std::filesystem::path mAssetsPath;

	std::map<std::filesystem::path, std::list<std::function<void(const std::filesystem::path& path)>>> m_callbacks;
	std::map<std::filesystem::path, std::list<std::function<void(const std::filesystem::path& path)>>> m_directoryCallbacks;

};


#endif //CYPHESIS_ASSETSMANAGER_H
