/*
 * Copyright 2006 - 2013
 *     Stefan Balev     <stefan.balev@graphstream-project.org>
 *     Julien Baudry    <julien.baudry@graphstream-project.org>
 *     Antoine Dutot    <antoine.dutot@graphstream-project.org>
 *     Yoann Pigné      <yoann.pigne@graphstream-project.org>
 *     Guilhelm Savin   <guilhelm.savin@graphstream-project.org>
 * 
 * This file is part of GraphStream <http://graphstream-project.org>.
 * 
 * GraphStream is a library whose purpose is to handle static or dynamic
 * graph, create them from scratch, file or any source and display them.
 * 
 * This program is free software distributed under the terms of two licenses, the
 * CeCILL-C license that fits European law, and the GNU Lesser General Public
 * License. You can  use, modify and/ or redistribute the software under the terms
 * of the CeCILL-C license as circulated by CEA, CNRS and INRIA at the following
 * URL <http://www.cecill.info> or under the terms of the GNU LGPL 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 Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 * 
 * The fact that you are presently reading this means that you have had
 * knowledge of the CeCILL-C and LGPL licenses and that you accept their terms.
 */
package org.graphstream.stream.file;

/**
 * Transform the input events into a GML graph.
 * 
 * <p>
 * THIS CLASS IS REALLY NOT APPROPRIATE FOR GENERAL USE. Indeed the GML format
 * is not dynamic and it is very difficult to export the correct attributes of
 * nodes if the declaration of the attribute is far from the declaration of the
 * node. The only way would be to store the graph in a buffer and output it at
 * once when the file is closed.
 * </p>
 * 
 * <p>
 * Therefore this class outputs attributes of nodes and edges only if their
 * addition directly follows the corresponding node or edge.
 * </p>
 */
public class FileSinkDynamicGML extends FileSinkGML {
        // Construction

        public FileSinkDynamicGML() {
                // NOP
        }

        // Attribute events

        @Override
        public void graphAttributeAdded(String sourceId, long timeId,
                        String attribute, Object value) {
                ensureToFinish();

                String val = valueToString(value);

                if (val != null) {
                        out.printf("\t%s %s%n", attribute, val);
                }
        }

        @Override
        public void graphAttributeChanged(String sourceId, long timeId,
                        String attribute, Object oldValue, Object newValue) {
                ensureToFinish();
                graphAttributeAdded(sourceId, timeId, attribute, newValue);
        }

        @Override
        public void graphAttributeRemoved(String sourceId, long timeId,
                        String attribute) {
                ensureToFinish();
                out.printf("\t-%s%n", attribute);
        }

        @Override
        public void nodeAttributeAdded(String sourceId, long timeId, String nodeId,
                        String attribute, Object value) {
                nodeAttributeChanged(sourceId, timeId, nodeId, attribute, null, value);
        }

        @Override
        public void nodeAttributeChanged(String sourceId, long timeId,
                        String nodeId, String attribute, Object oldValue, Object newValue) {

                if(nodeToFinish == null || (!nodeToFinish.equals(nodeId))) {
                        ensureToFinish();
                        out.printf("\t+node [%n");
                        out.printf("\t\tid \"%s\"%n", nodeId);
                        nodeToFinish = nodeId;
                }

                if(newValue != null) {
                        String val = valueToString(newValue);
                        
                        if (val != null) {
                                out.printf("\t\t%s %s%n", attribute, val);
                        }
                } else {
                        out.printf("\t\t-%s%n", attribute);
                }
        }

        @Override
        public void nodeAttributeRemoved(String sourceId, long timeId,
                        String nodeId, String attribute) {
                nodeAttributeChanged(sourceId, timeId, nodeId, attribute, null, null);
        }

        @Override
        public void edgeAttributeAdded(String sourceId, long timeId, String edgeId,
                        String attribute, Object value) {
                edgeAttributeChanged(sourceId, timeId, edgeId, attribute, null, value);
        }

        @Override
        public void edgeAttributeChanged(String sourceId, long timeId,
                        String edgeId, String attribute, Object oldValue, Object newValue) {

                if(edgeToFinish == null || (!edgeToFinish.equals(edgeId))) {
                        ensureToFinish();
                        out.printf("\t+edge [%n");
                        out.printf("\t\tid \"%s\"%n", edgeId);
                        edgeToFinish = edgeId;
                }

                if(newValue != null) {
                        String val = valueToString(newValue);
                        
                        if (val != null) {
                                out.printf("\t\t%s %s%n", attribute, val);
                        }
                } else {
                        out.printf("\t\t-%s%n", attribute);
                }
        }

        @Override
        public void edgeAttributeRemoved(String sourceId, long timeId,
                        String edgeId, String attribute) {
                edgeAttributeChanged(sourceId, timeId, edgeId, attribute, null, null);
        }

        // Element events

        @Override
        public void nodeAdded(String sourceId, long timeId, String nodeId) {
                ensureToFinish();
                out.printf("\tnode [%n");
                out.printf("\t\tid \"%s\"%n", nodeId);
                nodeToFinish = nodeId;
        }

        @Override
        public void nodeRemoved(String sourceId, long timeId, String nodeId) {
                ensureToFinish();
                out.printf("\t-node \"%s\"%n", nodeId);
        }

        @Override
        public void edgeAdded(String sourceId, long timeId, String edgeId,
                        String fromNodeId, String toNodeId, boolean directed) {
                ensureToFinish();
                out.printf("\tedge [%n");
                out.printf("\t\tid \"%s\"%n", edgeId);
                out.printf("\t\tsource \"%s\"%n", fromNodeId);
                out.printf("\t\ttarget \"%s\"%n", toNodeId);
                out.printf("\t\tdirected %s%n", directed ? "1" : "0");
                edgeToFinish = edgeId;
        }

        @Override
        public void edgeRemoved(String sourceId, long timeId, String edgeId) {
                ensureToFinish();
                out.printf("\t-edge \"%s\"%n", edgeId);
        }

        @Override
        public void graphCleared(String sourceId, long timeId) {
                // Ah ah ah !!
        }

        @Override
        public void stepBegins(String sourceId, long timeId, double step) {
                ensureToFinish();
                if((step-((int)step))==0) 
                     out.printf("\tstep %d%n", (int)step);
                else out.printf("\tstep %f%n", step);
        }
}