package org.llgc;

import java.io.File;
import java.io.IOException;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.helpers.DefaultHandler;

public class XMLSAX extends DefaultHandler
{
  private boolean close = false;
  private int deep = 0;
  private Deep0 pos0 = Deep0.UNKNOWN;
  private Deep1 pos1 = Deep1.UNKNOWN;
  private Deep2 pos2 = Deep2.UNKNOWN;

  public enum Deep0
  {
    UNKNOWN, CONTACTS
  };

  public enum Deep1
  {
    UNKNOWN, CONTACT
  };

  public enum Deep2
  {
    UNKNOWN, NOM, PRENOM, IP
  };

  @Override
  public void startDocument () throws SAXException
  {
    System.out.println ("Liste des documents");
    close = false;
    deep = 0;
  }

  @Override
  public void startElement (String uri, String localName, String qName, Attributes attributes) throws SAXException
  {
    close = false;
    switch (deep)
    {
      case 0:
      {
        if (qName.equals ("contacts"))
        {
          pos0 = Deep0.CONTACTS;
        }
        else
        {
          fatalError (new SAXParseException ("Fichier invalide. Élément racine incorrect : " + qName + ".", null));
        }
        break;
      }
      case 1:
      {
        if (qName.equals ("contact"))
        {
          pos1 = Deep1.CONTACT;
        }
        else
        {
          fatalError (new SAXParseException ("Fichier invalide. Élément niveau 1 incorrect : " + qName + ".", null));
        }
        break;
      }
      case 2:
      {
        if (qName.equals ("nom"))
        {
          pos2 = Deep2.NOM;
        }
        else if (qName.equals ("prenom"))
        {
          pos2 = Deep2.PRENOM;
        }
        else if (qName.equals ("ip"))
        {
          pos2 = Deep2.IP;
        }
        else
        {
          fatalError (new SAXParseException ("Fichier invalide. Élément niveau 2 incorrect : " + qName + ".", null));
        }
        break;
      }
      default:
      {
        fatalError (new SAXParseException ("Fichier invalide. Niveau d'arborescence (3) trop grand.", null));
        break;
      }
    }
    if ( (pos0 == Deep0.CONTACTS) && (pos1 == Deep1.CONTACT) && (pos2 == Deep2.UNKNOWN))
    {
      System.out.println (qName + " - " + attributes.getValue ("id") + " : ");
    }
    deep++;
  }

  @Override
  public void characters (char[] ch, int start, int length) throws SAXException
  {
    if (close)
    {
      return;
    }

    if ( (ch[start] != '\n') && (pos0 == Deep0.CONTACTS) && (pos1 == Deep1.CONTACT))
    {
      switch (pos2)
      {
        case NOM:
          System.out.print ("Nom : ");
          break;
        case PRENOM:
          System.out.print ("Prénom : ");
          break;
        case IP:
          System.out.print ("IP : ");
          break;
        default:
          fatalError (new SAXParseException ("Fichier invalide. Type inconnu.", null)); // Erreur
                                                                                        // impossible
                                                                                        // normalement.
          break;
      }
      System.out.println (new String (ch, start, length));
    }
  }

  @Override
  public void endElement (String uri, String localName, String qName) throws SAXException
  {
    deep--;
    switch (deep)
    {
      case 0:
        pos0 = Deep0.UNKNOWN;
        break;
      case 1:
        pos1 = Deep1.UNKNOWN;
        break;
      case 2:
        pos2 = Deep2.UNKNOWN;
        break;
      default:
        // Erreur impossible normalement.
        fatalError (new SAXParseException ("Fichier invalide. Type inconnu.", null));
        break;
    }
    close = true;
  }

  @Override
  public void endDocument () throws SAXException
  {
    close = true;
  }

  @Override
  public void fatalError (SAXParseException e) throws SAXException
  {
    throw new SAXException (e);
  }

  public static void main (String[] args)
  {
    SAXParserFactory factory = SAXParserFactory.newInstance ();
    try
    {
      SAXParser parser = factory.newSAXParser ();
      parser.parse (new File ("contact.xml"), new XMLSAX ());
    }
    catch (ParserConfigurationException | SAXException | IOException e)
    {
      e.printStackTrace ();
      return;
    }
  }
}