// This file is part of RSS Guard.
//
// Copyright (C) 2011-2017 by Martin Rotter <rotter.martinos@gmail.com>
//
// RSS Guard 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 3 of the License, or
// (at your option) any later version.
//
// RSS Guard 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 RSS Guard. If not, see <http://www.gnu.org/licenses/>.

#ifndef APPLICATION_H
#define APPLICATION_H

#include "qtsingleapplication/qtsingleapplication.h"

#include "definitions/definitions.h"
#include "miscellaneous/settings.h"
#include "miscellaneous/systemfactory.h"
#include "miscellaneous/skinfactory.h"
#include "miscellaneous/localization.h"
#include "miscellaneous/databasefactory.h"
#include "miscellaneous/iofactory.h"
#include "gui/systemtrayicon.h"
#include "network-web/downloadmanager.h"
#include "core/feeddownloader.h"

#include <QList>

#if defined(qApp)
#undef qApp
#endif

// Define new qApp macro. Yeaaaaah.
#define qApp (Application::instance())


class FormMain;
class IconFactory;
class QAction;
class Mutex;
class QWebEngineDownloadItem;
class FeedReader;
class WebFactory;

#if defined(USE_WEBENGINE)
class NetworkUrlInterceptor;
#endif

class Application : public QtSingleApplication {
		Q_OBJECT

	public:
		// Constructors and destructors.
		explicit Application(const QString& id, int& argc, char** argv);
		virtual ~Application();

		FeedReader* feedReader();
		void setFeedReader(FeedReader* feed_reader);

		// Globally accessible actions.
		QList<QAction*> userActions();

		// Check whether this application starts for the first time (ever).
		bool isFirstRun();

		// Check whether GIVEN VERSION of the application starts for the first time.
		bool isFirstRun(const QString& version);

    WebFactory* web();
		SystemFactory* system();
		SkinFactory* skins();
		Localization* localization();
		DatabaseFactory* database();
		IconFactory* icons();
		DownloadManager* downloadManager();
		Settings* settings();
		Mutex* feedUpdateLock();
		FormMain* mainForm();
		QWidget* mainFormWidget();
		SystemTrayIcon* trayIcon();

#if defined(USE_WEBENGINE)
		NetworkUrlInterceptor* urlIinterceptor();
#endif

		QString getTempFolderPath();
		QString getDocumentsFolderPath();
		QString getHomeFolderPath();
		QString getConfigHomePath();

		// These return user ready folders.
		QString getUserDataAppPath();
		QString getUserDataHomePath();

		// Returns the base folder to which store user data, the "data" folder.
		// NOTE: Use this to get correct path under which store user data.
		QString getUserDataPath();

		void setMainForm(FormMain* main_form);

		void backupDatabaseSettings(bool backup_database, bool backup_settings,
		                            const QString& target_path, const QString& backup_name);
		void restoreDatabaseSettings(bool restore_database, bool restore_settings,
		                             const QString& source_database_file_path = QString(),
		                             const QString& source_settings_file_path = QString());

		void showTrayIcon();
		void deleteTrayIcon();

		// Displays given simple message in tray icon bubble or OSD
		// or in message box if tray icon is disabled.
		void showGuiMessage(const QString& title, const QString& message, QSystemTrayIcon::MessageIcon message_type,
		                    QWidget* parent = nullptr, bool show_at_least_msgbox = false,
		                    QObject* invokation_target = nullptr, const char* invokation_slot = nullptr);

		// Returns pointer to "GOD" application singleton.
		inline static Application* instance() {
			return static_cast<Application*>(QCoreApplication::instance());
		}

	public slots:
		// Restarts the application.
		void restart();

		// Processes incoming message from another RSS Guard instance.
		void processExecutionMessage(const QString& message);

	private slots:
		// Last-minute reactors.
		void onCommitData(QSessionManager& manager);
		void onSaveState(QSessionManager& manager);
		void onAboutToQuit();

#if defined(USE_WEBENGINE)
		void downloadRequested(QWebEngineDownloadItem* download_item);
#endif

		void onFeedUpdatesStarted();
		void onFeedUpdatesProgress(const Feed* feed, int current, int total);
		void onFeedUpdatesFinished(FeedDownloadResults results);

	private:
		void eliminateFirstRun();
		void eliminateFirstRun(const QString& version);

#if defined(USE_WEBENGINE)
    NetworkUrlInterceptor* m_urlInterceptor;
#endif

		FeedReader* m_feedReader;

		// This read-write lock is used by application on its close.
		// Application locks this lock for WRITING.
		// This means that if application locks that lock, then
		// no other transaction-critical action can acquire lock
		// for reading and won't be executed, so no critical action
		// will be running when application quits
		//
		// EACH critical action locks this lock for READING.
		// Several actions can lock this lock for reading.
		// But of user decides to close the application (in other words,
		// tries to lock the lock for writing), then no other
		// action will be allowed to lock for reading.
		QScopedPointer<Mutex> m_updateFeedsLock;

		QList<QAction*> m_userActions;
		FormMain* m_mainForm;
		SystemTrayIcon* m_trayIcon;
		Settings* m_settings;
    WebFactory* m_webFactory;
		SystemFactory* m_system;
		SkinFactory* m_skins;
		Localization* m_localization;
		IconFactory* m_icons;
		DatabaseFactory* m_database;
		DownloadManager* m_downloadManager;
		bool m_shouldRestart;
};

#endif // APPLICATION_H