DefaultEbicsRootElement.java

/*
 * Copyright (c) 1990-2012 kopiLeft Development SARL, Bizerte, Tunisia
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License version 2.1 as published by the Free Software Foundation.
 *
 * This library 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 library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 */

package org.kopi.ebics.xml;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintStream;
import java.math.BigInteger;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import javax.xml.namespace.QName;

import org.apache.xml.security.c14n.Canonicalizer;
import org.apache.xmlbeans.XmlCursor;
import org.apache.xmlbeans.XmlError;
import org.apache.xmlbeans.XmlObject;
import org.apache.xmlbeans.XmlOptions;
import org.kopi.ebics.exception.EbicsException;
import org.kopi.ebics.interfaces.EbicsOrderType;
import org.kopi.ebics.interfaces.EbicsRootElement;
import org.kopi.ebics.session.EbicsSession;
import org.kopi.ebics.utils.Utils;

public abstract class DefaultEbicsRootElement implements EbicsRootElement {

  /**
   * Constructs a new default <code>EbicsRootElement</code>
   * @param session the current ebics session
   */
  protected DefaultEbicsRootElement(EbicsSession session) {
    this.session = session;
    suggestedPrefixes = new HashMap<>();
  }

  /**
   *  Constructs a new default <code>EbicsRootElement</code>
   */
  protected DefaultEbicsRootElement() {
    this(null);
  }

  /**
   * Saves the Suggested Prefixes when the XML is printed
   * @param uri the namespace URI
   * @param prefix the namespace URI prefix
   */
  protected void setSaveSuggestedPrefixes(String uri, String prefix) {
    suggestedPrefixes.put(uri, prefix);
  }

  /**
   * Prints a pretty XML document in Canonical XML.
   * @return the canonical XML document.
   */
  public byte[] prettyPrint() {
      try {
          Canonicalizer canon = Canonicalizer.getInstance(Canonicalizer.ALGO_ID_C14N_OMIT_COMMENTS);
          var bos = new ByteArrayOutputStream();
          canon.canonicalize(toByteArray(), bos, true);
          return bos.toByteArray();
      } catch (Exception e) {
          throw new RuntimeException("Failed to canonicalize XML", e);
      }
  }

    public String toPrettyString() {
        return new String(prettyPrint(), StandardCharsets.UTF_8);
    }

  /**
   * Inserts a schema location to the current ebics root element.
   * @param namespaceURI the name space URI
   * @param localPart the local part
   * @param prefix the prefix
   * @param value the value
   */
  public void insertSchemaLocation(String namespaceURI,
                                   String localPart,
                                   String prefix,
                                   String value)
  {

      try (XmlCursor cursor = document.newCursor()) {
          while (cursor.hasNextToken()) {
              if (cursor.isStart()) {
                  cursor.toNextToken();
                  cursor.insertAttributeWithValue(new QName(namespaceURI, localPart, prefix),
                      value);
                  break;
              } else {
                  cursor.toNextToken();
              }
          }
      }
  }

  /**
   * Generates a random file name with a prefix.
   * @param type the order type.
   * @return the generated file name.
   */
  public static String generateName(EbicsOrderType type) {
    return type.getCode() + new BigInteger(130, Utils.secureRandom).toString(32);
  }
  
  /**
   * Generates a random file name with a prefix.
   * @param prefix the prefix to use.
   * @return the generated file name.
   */
  public static String generateName(String prefix) {
    return prefix + new BigInteger(130, Utils.secureRandom).toString(32);
  }

  @Override
  public String toString() {
    return new String(toByteArray());
  }

  @Override
  public byte[] toByteArray() {
    XmlOptions		options;

    options = new XmlOptions();
    options.setSavePrettyPrint();
    options.setSaveSuggestedPrefixes(suggestedPrefixes);
    return document.xmlText(options).getBytes();
  }

  @Override
  public void addNamespaceDecl(String prefix, String uri) {
      try (XmlCursor cursor = document.newCursor()) {
          while (cursor.hasNextToken()) {
              if (cursor.isStart()) {
                  cursor.toNextToken();
                  cursor.insertNamespace(prefix, uri);
                  break;
              } else {
                  cursor.toNextToken();
              }
          }
      }
  }

  @Override
  public void validate() throws EbicsException {
    List<XmlError> validationMessages = new ArrayList<>();
    boolean isValid = document.validate(new XmlOptions().setErrorListener(validationMessages));

    if (!isValid) {
      Iterator<XmlError> iter = validationMessages.iterator();
      StringBuilder message = new StringBuilder();
      while (iter.hasNext()) {
        if (!message.toString().isEmpty()) {
          message.append(";");
        }
        message.append(iter.next().getMessage());
      }

        throw new EbicsException(
            "Invalid " + this.getClass().getSimpleName() + ": " + message);
    }
  }

  @Override
  public void save(OutputStream out) throws EbicsException {
      try {
          byte[] element = prettyPrint();
          out.write(element);
          out.flush();
          out.close();
      } catch (IOException e) {
          throw new EbicsException(e.getMessage());
      }
  }

  @Override
  public void print(PrintStream stream) {
    stream.println(document.toString());
  }

  // --------------------------------------------------------------------
  // DATA MEMBERS
  // --------------------------------------------------------------------

  protected XmlObject			document;
  protected EbicsSession 		session;
  private final Map<String, String> 	suggestedPrefixes;
  private static final long 		serialVersionUID = -3928957097145095177L;
}