/*******************************************************************************
    * 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.reader;
  
  import java.io.FileNotFoundException;
  import java.io.IOException;
  import java.io.PrintWriter;
  import java.net.URL;
  import java.util.Locale;
  
  import org.sat4j.specs.ContradictionException;
  import org.sat4j.specs.IProblem;
  import org.sat4j.specs.ISolver;
  
  /**
   * An reader having the responsability to choose the right reader according to
   * the input.
   * 
   * @author leberre
   */
  public class InstanceReader extends Reader {
  
      private AAGReader aag;
  
      private AIGReader aig;
  
      private DimacsReader ezdimacs;
  
      private LecteurDimacs dimacs;
  
      private Reader reader = null;
  
      private final ISolver solver;
  
      public InstanceReader(ISolver solver) {
          // dimacs = new DimacsReader(solver);
          this.solver = solver;
      }
  
      private Reader getDefaultSATReader() {
          if (this.dimacs == null) {
              this.dimacs = new LecteurDimacs(this.solver);// new
                                                           // LecteurDimacs(solver);
          }
          return this.dimacs;
      }
  
      private Reader getEZSATReader() {
          if (this.ezdimacs == null) {
              this.ezdimacs = new DimacsReader(this.solver);// new
                                                            // LecteurDimacs(solver);
          }
          return this.ezdimacs;
      }
  
      private Reader getAIGReader() {
          if (this.aig == null) {
              this.aig = new AIGReader(this.solver);
          }
          return this.aig;
      }
  
      private Reader getAAGReader() {
          if (this.aag == null) {
              this.aag = new AAGReader(this.solver);
          }
          return this.aag;
      }
  
      @Override
      public IProblem parseInstance(String filename)
              throws FileNotFoundException, ParseFormatException, IOException,
             ContradictionException {
         String fname;
         boolean isHttp = false;
         String tempFileName = "";
         String prefix = "";
 
         if (filename.startsWith("http://")) {
             isHttp = true;
             tempFileName = filename;
             filename = filename.substring(filename.lastIndexOf('/'),
                     filename.length() - 1);
         }
 
         if (filename.indexOf(':') != -1) {
 
             String[] parts = filename.split(":");
             filename = parts[1];
             prefix = parts[0].toUpperCase(Locale.getDefault());
 
         }
 
         if (filename.endsWith(".gz")) {
             fname = filename.substring(0, filename.lastIndexOf('.'));
         } else {
             fname = filename;
         }
         if ("EZCNF".equals(prefix)) {
             this.reader = getEZSATReader();
         } else if (fname.endsWith(".aag")) {
             this.reader = getAAGReader();
         } else if (fname.endsWith(".aig")) {
             this.reader = getAIGReader();
 
         } else {
             this.reader = getDefaultSATReader();
         }
 
         if (isHttp) {
             return this.reader
                     .parseInstance(new URL(tempFileName).openStream());
         }
         return this.reader.parseInstance(filename);
     }
 
     @Override
     @Deprecated
     public String decode(int[] model) {
         return this.reader.decode(model);
     }
 
     @Override
     public void decode(int[] model, PrintWriter out) {
         this.reader.decode(model, out);
     }
 
     @Override
     public IProblem parseInstance(java.io.InputStream in)
             throws ParseFormatException, ContradictionException, IOException {
         throw new UnsupportedOperationException(
                 "Use a domain specific Reader (LecteurDimacs, AIGReader, etc.) for stream input ");
     }
 
 }