/*******************************************************************************
    * SAT4J: a SATisfiability library for Java Copyright (C) 2004-2008 Daniel Le Berre
    *
    * All rights reserved. This program and the accompanying materials
    * are made available under the terms of the Eclipse Public License v1.0
    * which accompanies this distribution, and is available at
    * http://www.eclipse.org/legal/epl-v10.html
    *
    * Alternatively, the contents of this file may be used under the terms of
   * either the GNU Lesser General Public License Version 2.1 or later (the
   * "LGPL"), in which case the provisions of the LGPL are applicable instead
   * of those above. If you wish to allow use of your version of this file only
   * under the terms of the LGPL, and not to allow others to use your version of
   * this file under the terms of the EPL, indicate your decision by deleting
   * the provisions above and replace them with the notice and other provisions
   * required by the LGPL. If you do not delete the provisions above, a recipient
   * may use your version of this file under the terms of the EPL or the LGPL.
   * 
   * Based on the original MiniSat specification from:
   * 
   * An extensible SAT solver. Niklas Een and Niklas Sorensson. Proceedings of the
   * Sixth International Conference on Theory and Applications of Satisfiability
   * Testing, LNCS 2919, pp 502-518, 2003.
   *
   * See www.minisat.se for the original solver in C++.
   * 
   *******************************************************************************/
  package org.sat4j.minisat.core;
  
  import java.io.FileWriter;
  import java.io.IOException;
  import java.io.ObjectInputStream;
  import java.io.PrintWriter;
  import java.io.Writer;
  import java.util.Map;
  
  import org.sat4j.core.Vec;
  import org.sat4j.specs.IConstr;
  import org.sat4j.specs.Lbool;
  import org.sat4j.specs.SearchListener;
  
  /**
   * Class allowing to express the search as a tree in the dot language. The
   * resulting file can be viewed in a tool like <a
   * href="http://www.graphviz.org/">Graphviz</a>
   * 
   * To use only on small benchmarks.
   * 
   * Note that also does not make sense to use such a listener on a distributed or
   * remote solver.
   * 
   * @author daniel
   * 
   */
  public class DotSearchListener<T> implements SearchListener {
  
  	/**
       * 
       */
  	private static final long serialVersionUID = 1L;
  
  	private final Vec<String> pile;
  
  	private String currentNodeName = null;
  
  	private transient Writer out;
  
  	private boolean estOrange = false;
  
  	private final Map<Integer, T> mapping;
  
  	/**
  	 * @since 2.1
  	 */
  	public DotSearchListener(final String fileNameToSave,
  			Map<Integer, T> mapping) {
  		pile = new Vec<String>();
  		this.mapping = mapping;
  		try {
  			out = new FileWriter(fileNameToSave);
  		} catch (IOException e) {
  			System.err.println("Problem when created file.");
  		}
  	}
  
  	private String node(int dimacs) {
  		if (mapping != null) {
  			int var = Math.abs(dimacs);
  			T t = mapping.get(var);
  			if (t != null) {
  				if (dimacs > 0)
  					return t.toString();
  				return "-" + t.toString();
  			}
  		}
  		return Integer.toString(dimacs);
  	}
  
  	public final void assuming(final int p) {
 		final int absP = Math.abs(p);
 		String newName;
 
 		if (currentNodeName == null) {
 			newName = "" + absP;
 			pile.push(newName);
 			saveLine(lineTab("\"" + newName + "\"" + "[label=\"" + node(p)
 					+ "\", shape=circle, color=blue, style=filled]"));
 		} else {
 			newName = currentNodeName;
 			pile.push(newName);
 			saveLine(lineTab("\"" + newName + "\"" + "[label=\"" + node(p)
 					+ "\", shape=circle, color=blue, style=filled]"));
 		}
 		currentNodeName = newName;
 	}
 
 	/**
 	 * @since 2.1
 	 */
 	public final void propagating(final int p, IConstr reason) {
 		String newName = currentNodeName + "." + p;
 
 		if (currentNodeName == null) {
 			saveLine(lineTab("\"null\" [label=\"\", shape=point]"));
 		}
 		final String couleur = estOrange ? "orange" : "green";
 
 		saveLine(lineTab("\"" + newName + "\"" + "[label=\"" + node(p)
 				+ "\",shape=point, color=black]"));
 		saveLine(lineTab("\"" + currentNodeName + "\"" + " -- " + "\""
 				+ newName + "\"" + "[label=" + "\" " + node(p)
 				+ "\", fontcolor =" + couleur + ", color = " + couleur
 				+ ", style = bold]"));
 		currentNodeName = newName;
 		estOrange = false;
 	}
 
 	public final void backtracking(final int p) {
 		final String temp = pile.last();
 		pile.pop();
 		saveLine("\"" + temp + "\"" + "--" + "\"" + currentNodeName + "\""
 				+ "[label=\"\", color=red, style=dotted]");
 		currentNodeName = temp;
 	}
 
 	public final void adding(final int p) {
 		estOrange = true;
 	}
 
 	/**
 	 * @since 2.1
 	 */
 	public final void learn(final IConstr clause) {
 	}
 
 	public final void delete(final int[] clause) {
 	}
 
 	/**
 	 * @since 2.1
 	 */
 	public final void conflictFound(IConstr confl) {
 		saveLine(lineTab("\"" + currentNodeName
 				+ "\" [label=\"\", shape=box, color=\"red\", style=filled]"));
 	}
 
 	/**
 	 * @since 2.1
 	 */
 	public final void conflictFound(int p) {
 		saveLine(lineTab("\"" + currentNodeName
 				+ "\" [label=\"\", shape=box, color=\"red\", style=filled]"));
 	}
 
 	public final void solutionFound() {
 		saveLine(lineTab("\"" + currentNodeName
 				+ "\" [label=\"\", shape=box, color=\"green\", style=filled]"));
 	}
 
 	public final void beginLoop() {
 	}
 
 	public final void start() {
 		saveLine("graph G {");
 	}
 
 	/**
 	 * @since 2.1
 	 */
 	public final void end(Lbool result) {
 		saveLine("}");
 	}
 
 	private final String lineTab(final String line) {
 		return "\t" + line;
 	}
 
 	private final void saveLine(final String line) {
 		try {
 			out.write(line + '\n');
 			if ("}".equals(line)) {
 				out.close();
 			}
 		} catch (IOException e) {
 			e.printStackTrace();
 		}
 	}
 
 	private void readObject(ObjectInputStream stream) throws IOException,
 			ClassNotFoundException {
 		// if the solver is serialized, out is linked to stdout
 		stream.defaultReadObject();
 		out = new PrintWriter(System.out);
 	}
 }