/*******************************************************************************
    * SAT4J: a SATisfiability library for Java Copyright (C) 2004, 2012 Artois University and CNRS
    *
    * 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++.
   *
   * Contributors:
   *   CRIL - initial API and implementation
   *******************************************************************************/
  package org.sat4j.tools;
  
  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.ISolverService;
  import org.sat4j.specs.Lbool;
  
  /**
   * 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
   * @since 2.2
   */
  public class DotSearchTracing<T> extends SearchListenerAdapter<ISolverService> {
  
      /**
       * 
       */
      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 DotSearchTracing(final String fileNameToSave, Map<Integer, T> mapping) {
          this.pile = new Vec<String>();
          this.mapping = mapping;
          try {
              this.out = new FileWriter(fileNameToSave);
          } catch (IOException e) {
              System.err.println("Problem when created file.");
          }
      }
  
      private String node(int dimacs) {
          if (this.mapping != null) {
              int var = Math.abs(dimacs);
              T t = this.mapping.get(var);
              if (t != null) {
                  if (dimacs > 0) {
                      return t.toString();
                  }
                  return "-" + t.toString();
              }
          }
          return Integer.toString(dimacs);
      }
 
     @Override
     public final void assuming(final int p) {
         final int absP = Math.abs(p);
         String newName;
 
         if (this.currentNodeName == null) {
             newName = "" + absP;
             this.pile.push(newName);
             saveLine(lineTab("\"" + newName + "\"" + "[label=\"" + node(p)
                     + "\", shape=circle, color=blue, style=filled]"));
         } else {
             newName = this.currentNodeName;
             this.pile.push(newName);
             saveLine(lineTab("\"" + newName + "\"" + "[label=\"" + node(p)
                     + "\", shape=circle, color=blue, style=filled]"));
         }
         this.currentNodeName = newName;
     }
 
     /**
      * @since 2.1
      */
     @Override
     public final void propagating(final int p, IConstr reason) {
         String newName = this.currentNodeName + "." + p;
 
         if (this.currentNodeName == null) {
             saveLine(lineTab("\"null\" [label=\"\", shape=point]"));
         }
         final String couleur = this.estOrange ? "orange" : "green";
 
         saveLine(lineTab("\"" + newName + "\"" + "[label=\"" + node(p)
                 + "\",shape=point, color=black]"));
         saveLine(lineTab("\"" + this.currentNodeName + "\"" + " -- " + "\""
                 + newName + "\"" + "[label=" + "\" " + node(p)
                 + "\", fontcolor =" + couleur + ", color = " + couleur
                 + ", style = bold]"));
         this.currentNodeName = newName;
         this.estOrange = false;
     }
 
     @Override
     public final void backtracking(final int p) {
         final String temp = this.pile.last();
         this.pile.pop();
         saveLine("\"" + temp + "\"" + "--" + "\"" + this.currentNodeName + "\""
                 + "[label=\"\", color=red, style=dotted]");
         this.currentNodeName = temp;
     }
 
     @Override
     public final void adding(final int p) {
         this.estOrange = true;
     }
 
     /**
      * @since 2.1
      */
     @Override
     public final void learn(final IConstr clause) {
     }
 
     @Override
     public final void delete(final int[] clause) {
     }
 
     /**
      * @since 2.1
      */
     @Override
     public final void conflictFound(IConstr confl, int dlevel, int trailLevel) {
         saveLine(lineTab("\"" + this.currentNodeName
                 + "\" [label=\"\", shape=box, color=\"red\", style=filled]"));
     }
 
     /**
      * @since 2.1
      */
     @Override
     public final void conflictFound(int p) {
         saveLine(lineTab("\"" + this.currentNodeName
                 + "\" [label=\"\", shape=box, color=\"red\", style=filled]"));
     }
 
     @Override
     public final void solutionFound(int[] model) {
         saveLine(lineTab("\"" + this.currentNodeName
                 + "\" [label=\"\", shape=box, color=\"green\", style=filled]"));
     }
 
     @Override
     public final void beginLoop() {
     }
 
     @Override
     public final void start() {
         saveLine("graph G {");
     }
 
     /**
      * @since 2.1
      */
     @Override
     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 {
             this.out.write(line + '\n');
             if ("}".equals(line)) {
                 this.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();
         this.out = new PrintWriter(System.out);
     }
 }