/** \file
 * \brief Declaration of the Fraysseix, Pach, Pollack Algorithm (FPPLayout)
 *        algorithm.
 *
 * \author Till Schäfer
 *
 * \par License:
 * This file is part of the Open Graph Drawing Framework (OGDF).
 *
 * \par
 * Copyright (C)<br>
 * See README.md in the OGDF root directory for details.
 *
 * \par
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * Version 2 or 3 as published by the Free Software Foundation;
 * see the file LICENSE.txt included in the packaging of this file
 * for details.
 *
 * \par
 * 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.
 *
 * \par
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, see
 * http://www.gnu.org/copyleft/gpl.html
 */

#pragma once

#include <ogdf/basic/Graph.h>
#include <ogdf/basic/basic.h>
#include <ogdf/basic/geometry.h>
#include <ogdf/planarlayout/GridLayoutModule.h>

namespace ogdf {
class GraphCopy;
class GridLayout;

/**
 * The class FPPLayout represents the layout algorithm by
 * de Fraysseix, Pach, Pollack [DPP90]. This algorithm draws a planar graph G
 * straight-line without crossings. G must not contain self-loops or multiple
 * edges. The grid layout size is (2<i>n</i>-4) * (<i>n</i>-2) for a graph with
 * n nodes (<i>n</i> ≥ 3).
 * The algorithm runs in three phases. In the ﬁrst phase, the graph is
 * augmented by adding new artiﬁcial edges to get a triangulated plane graph.
 * Then, a so-called shelling order (also called canonical ordering)
 * for triangulated planar graphs is computed. In the third phase the vertices
 * are placed incrementally according to the shelling order.
 */
class OGDF_EXPORT FPPLayout : public PlanarGridLayoutModule {
public:
	FPPLayout();

private:
	virtual void doCall(const Graph& G, adjEntry adjExternal, GridLayout& gridLayout,
			IPoint& boundingBox, bool fixEmbedding) override;

	void computeOrder(const GraphCopy& G, NodeArray<int>& num, NodeArray<adjEntry>& e_wp,
			NodeArray<adjEntry>& e_wq, adjEntry e_12, adjEntry e_2n, adjEntry e_n1);

	void computeCoordinates(const GraphCopy& G, IPoint& boundingBox, GridLayout& gridLayout,
			NodeArray<int>& num, NodeArray<adjEntry>& e_wp, NodeArray<adjEntry>& e_wq);
};

}
