src/messagelog.h

/*
 *  LDForge: LDraw parts authoring CAD
 *  Copyright (C) 2013 Santeri Piippo
 *
 *  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 3 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, see <http://www.gnu.org/licenses/>.
 */

#ifndef MESSAGELOG_H
#define MESSAGELOG_H

#include <QObject>
#include <QDate>
#include "common.h"
#include "types.h"

class GLRenderer;
class QTimer;

/* The message manager is an object which keeps track of messages that appear
 * on the renderer's screen. Each line is contained in a separate object which
 * contains the text, expiry time and alpha. The message manager is doubly
 * linked to its corresponding renderer.
 *
 * Message manager calls its tick() function regularly to update the messages,
 * where each line's expiry is checked for. Lines begin to fade out when nearing
 * their expiry. If the message manager's lines change, the renderer undergoes
 * repainting.
 */
class MessageManager : public QObject {
	Q_OBJECT
	PROPERTY (GLRenderer*, renderer, setRenderer)
	
public:
	// Single line of the message log.
	class Line {
	public:
		Line (str text);
		bool update (bool& changed);
		
		str text;
		float alpha;
		QDateTime expiry;
	};
	
	typedef List<Line>::it it;
	typedef List<Line>::c_it c_it;
	
	explicit MessageManager (QObject* parent = 0);
	void addLine (str line);
	c_it begin() const;
	c_it end() const;
	
	MessageManager& operator<< (str line);
	
private:
	List<Line> m_lines;
	QTimer* m_ticker;
	
private slots:
	void tick();
};

#endif // MESSAGELOG_H