/*

 */

/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (the "License"); you may not use this file except in compliance with

 * the License.  You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.sun.org.apache.xml.internal.utils;

import java.util.StringTokenizer;

import javax.xml.transform.Source;

import javax.xml.transform.TransformerException;

import javax.xml.transform.URIResolver;

import javax.xml.transform.sax.SAXSource;

import org.xml.sax.Attributes;

import org.xml.sax.InputSource;

import org.xml.sax.helpers.DefaultHandler;

/**

 * Search for the xml-stylesheet processing instructions in an XML document.

 */

public class StylesheetPIHandler extends DefaultHandler

{

  /** The baseID of the document being processed.  */

  String m_baseID;

  /** The desired media criteria. */

  String m_media;

  /** The desired title criteria.  */

  String m_title;

  /** The desired character set criteria.   */

  String m_charset;

  /** A list of SAXSource objects that match the criteria.  */

  // Add code to use a URIResolver. Patch from Dmitri Ilyin.

  /**

   * The object that implements the URIResolver interface,

   * or null.

   */

  URIResolver m_uriResolver;

  /**

   * Get the object that will be used to resolve URIs in href

   * in xml-stylesheet processing instruction.

   *

   * @param resolver An object that implements the URIResolver interface,

   * or null.

   */

  public void setURIResolver(URIResolver resolver)

  {

    m_uriResolver = resolver;

  }

  /**

   * Get the object that will be used to resolve URIs in href

   * in xml-stylesheet processing instruction.

   *

   * @return The URIResolver that was set with setURIResolver.

   */

  public URIResolver getURIResolver()

  {

    return m_uriResolver;

  }

  /**

   * Construct a StylesheetPIHandler instance that will search

   * for xml-stylesheet PIs based on the given criteria.

   *

   * @param baseID The base ID of the XML document, needed to resolve

   *               relative IDs.

   * @param media The desired media criteria.

   * @param title The desired title criteria.

   * @param charset The desired character set criteria.

   */

  public StylesheetPIHandler(String baseID, String media, String title,

                             String charset)

  {

    m_baseID = baseID;

    m_media = media;

    m_title = title;

    m_charset = charset;

  }

  /**

   * Return the last stylesheet found that match the constraints.

   *

   * @return Source object that references the last stylesheet reference

   *         that matches the constraints.

   */

  public Source getAssociatedStylesheet()

  {

    int sz = m_stylesheets.size();

    if (sz > 0)

    {

      return source;

    }

    else

      return null;

  }

  /**

   * Handle the xml-stylesheet processing instruction.

   *

   * @param target The processing instruction target.

   * @param data The processing instruction data, or null if

   *             none is supplied.

   * @throws org.xml.sax.SAXException Any SAX exception, possibly

   *            wrapping another exception.

   * @see org.xml.sax.ContentHandler#processingInstruction

   */

  public void processingInstruction(String target, String data)

          throws org.xml.sax.SAXException

  {

    if (target.equals("xml-stylesheet"))

    {

      String href = null;  // CDATA #REQUIRED

      String type = null;  // CDATA #REQUIRED

      String title = null;  // CDATA #IMPLIED

      String media = null;  // CDATA #IMPLIED

      String charset = null;  // CDATA #IMPLIED

      boolean alternate = false;  // (yes|no) "no"

      StringTokenizer tokenizer = new StringTokenizer(data, " \t=\n", true);

      boolean lookedAhead = false;

      Source source = null;

      String token = "";

      while (tokenizer.hasMoreTokens())

      {

        if (!lookedAhead)

          token = tokenizer.nextToken();

        else

          lookedAhead = false;

        if (tokenizer.hasMoreTokens() &&

               (token.equals(" ") || token.equals("\t") || token.equals("=")))

          continue;

        String name = token;

        if (name.equals("type"))

        {

          token = tokenizer.nextToken();

          while (tokenizer.hasMoreTokens() &&

               (token.equals(" " ) || token.equals("\t") || token.equals("=")))

            token = tokenizer.nextToken();

          type = token.substring(1, token.length() - 1);

        }

        else if (name.equals("href"))

        {

          token = tokenizer.nextToken();

          while (tokenizer.hasMoreTokens() &&

               (token.equals(" " ) || token.equals("\t") || token.equals("=")))

            token = tokenizer.nextToken();

          href = token;

          if (tokenizer.hasMoreTokens())

          {

            token = tokenizer.nextToken();

            // If the href value has parameters to be passed to a

            // servlet(something like "foobar?id=12..."),

            // we want to make sure we get them added to

            // the href value. Without this check, we would move on

            // to try to process another attribute and that would be

            // wrong.

            // We need to set lookedAhead here to flag that we

            // already have the next token.

            while ( token.equals("=") && tokenizer.hasMoreTokens())

            {

              href = href + token + tokenizer.nextToken();

              if (tokenizer.hasMoreTokens())

              {

                token = tokenizer.nextToken();

                lookedAhead = true;

              }

              else

              {

                break;

              }

            }

          }

          href = href.substring(1, href.length() - 1);

          try

          {

            // Add code to use a URIResolver. Patch from Dmitri Ilyin.

            if (m_uriResolver != null)

            {

              source = m_uriResolver.resolve(href, m_baseID);

            }

           else

            {

              href = SystemIDResolver.getAbsoluteURI(href, m_baseID);

              source = new SAXSource(new InputSource(href));

            }

          }

          catch(TransformerException te)

          {

            throw new org.xml.sax.SAXException(te);

          }

        }

        else if (name.equals("title"))

        {

          token = tokenizer.nextToken();

          while (tokenizer.hasMoreTokens() &&

               (token.equals(" " ) || token.equals("\t") || token.equals("=")))

            token = tokenizer.nextToken();

          title = token.substring(1, token.length() - 1);

        }

        else if (name.equals("media"))

        {

          token = tokenizer.nextToken();

          while (tokenizer.hasMoreTokens() &&

               (token.equals(" " ) || token.equals("\t") || token.equals("=")))

            token = tokenizer.nextToken();

          media = token.substring(1, token.length() - 1);

        }

        else if (name.equals("charset"))

        {

          token = tokenizer.nextToken();

          while (tokenizer.hasMoreTokens() &&

              (token.equals(" " ) || token.equals("\t") || token.equals("=")))

            token = tokenizer.nextToken();

          charset = token.substring(1, token.length() - 1);

        }

        else if (name.equals("alternate"))

        {

          token = tokenizer.nextToken();

          while (tokenizer.hasMoreTokens() &&

               (token.equals(" " ) || token.equals("\t") || token.equals("=")))

            token = tokenizer.nextToken();

          alternate = token.substring(1, token.length()

                                             - 1).equals("yes");

        }

      }

      if ((null != type)

          && (type.equals("text/xsl") || type.equals("text/xml") || type.equals("application/xml+xslt"))

          && (null != href))

      {

        if (null != m_media)

        {

          if (null != media)

          {

            if (!media.equals(m_media))

              return;

          }

          else

            return;

        }

        if (null != m_charset)

        {

          if (null != charset)

          {

            if (!charset.equals(m_charset))

              return;

          }

          else

            return;

        }

        if (null != m_title)

        {

          if (null != title)

          {

            if (!title.equals(m_title))

              return;

          }

          else

            return;

        }

      }

    }

  }

  /**

   * The spec notes that "The xml-stylesheet processing instruction is allowed only in the prolog of an XML document.",

   * so, at least for right now, I'm going to go ahead an throw a TransformerException

   * in order to stop the parse.

   *

   * @param namespaceURI The Namespace URI, or an empty string.

   * @param localName The local name (without prefix), or empty string if not namespace processing.

   * @param qName The qualified name (with prefix).

   * @param atts  The specified or defaulted attributes.

   *

   * @throws StopParseException since there can be no valid xml-stylesheet processing

   *                            instructions past the first element.

   */

  public void startElement(

          String namespaceURI, String localName, String qName, Attributes atts)

            throws org.xml.sax.SAXException

  {

    throw new StopParseException();

  }

  /**

    * Added additional getter and setter methods for the Base Id

    * to fix bugzilla bug 24187

    *

    */

   public void setBaseId(String baseId) {

       m_baseID = baseId;

   }

   public String  getBaseId() {

       return m_baseID ;

   }

}