/*
    * Copyright (c) 2002-2026 Gargoyle Software Inc.
    *
    * Licensed 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
    * https://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 org.htmlunit.xml;
  
  import static java.nio.charset.StandardCharsets.UTF_8;
  
  import java.io.IOException;
  import java.nio.charset.Charset;
  import java.util.HashMap;
  
  import javax.xml.parsers.ParserConfigurationException;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.htmlunit.SgmlPage;
  import org.htmlunit.WebResponse;
  import org.htmlunit.WebWindow;
  import org.htmlunit.html.DomElement;
  import org.htmlunit.html.DomProcessingInstruction;
  import org.htmlunit.util.MimeType;
  import org.htmlunit.util.XmlUtils;
  import org.w3c.dom.Attr;
  import org.w3c.dom.DOMConfiguration;
  import org.w3c.dom.DOMImplementation;
  import org.w3c.dom.Document;
  import org.w3c.dom.DocumentType;
  import org.w3c.dom.Element;
  import org.w3c.dom.EntityReference;
  import org.w3c.dom.Node;
  import org.xml.sax.SAXException;
  
  /**
   * A page that will be returned for response with content type "text/xml".
   *
   * @author Marc Guillemot
   * @author David K. Taylor
   * @author Ahmed Ashour
   * @author Frank Danek
   * @author Ronald Brill
   */
  public class XmlPage extends SgmlPage {
  
      private static final Log LOG = LogFactory.getLog(XmlPage.class);
  
      private Node node_;
  
      /**
       * Creates an instance.
       * A warning is logged if an exception is thrown while parsing the XML content
       * (for instance when the content is not a valid XML and can't be parsed).
       *
       * @param webResponse the response from the server
       * @param enclosingWindow the window that holds the page
       * @throws IOException if the page could not be created
       */
      public XmlPage(final WebResponse webResponse, final WebWindow enclosingWindow) throws IOException {
          this(webResponse, enclosingWindow, true);
      }
  
      /**
       * Creates an instance.
       * A warning is logged if an exception is thrown while parsing the XML content
       * (for instance when the content is not a valid XML and can't be parsed).
       *
       * @param node the node to initialize this page with
       * @param enclosingWindow the window that holds the page
       */
      public XmlPage(final Node node, final WebWindow enclosingWindow) {
          super(null, enclosingWindow);
          node_ = node;
          if (node_ != null) {
              XmlUtils.appendChild(this, this, node_, true);
          }
      }
  
      /**
       * Creates an instance.
       * A warning is logged if an exception is thrown while parsing the XML content
       * (for instance when the content is not a valid XML and can't be parsed).
       *
       * @param webResponse the response from the server
       * @param enclosingWindow the window that holds the page
       * @param ignoreSAXException Whether to ignore {@link SAXException} or throw it as {@link IOException}
       * @throws IOException if the page could not be created
       */
      public XmlPage(final WebResponse webResponse, final WebWindow enclosingWindow, final boolean ignoreSAXException)
          throws IOException {
         this(webResponse, enclosingWindow, ignoreSAXException, true);
     }
 
     /**
      * Creates an instance.
      * A warning is logged if an exception is thrown while parsing the XML content
      * (for instance when the content is not a valid XML and can't be parsed).
      *
      * @param webResponse the response from the server
      * @param enclosingWindow the window that holds the page
      * @param ignoreSAXException Whether to ignore {@link SAXException} or throw it as {@link IOException}
      * @param handleXHTMLAsHTML if true elements from the XHTML namespace are handled as HTML elements instead of
      *     DOM elements
      * @throws IOException if the page could not be created
      */
     public XmlPage(final WebResponse webResponse, final WebWindow enclosingWindow, final boolean ignoreSAXException,
         final boolean handleXHTMLAsHTML) throws IOException {
         super(webResponse, enclosingWindow);
 
         try {
             try {
                 final Document document = XmlUtils.buildDocument(webResponse);
                 node_ = document.getFirstChild();
             }
             catch (final SAXException e) {
                 if (LOG.isWarnEnabled()) {
                     LOG.warn("Failed parsing XML document '" + webResponse.getWebRequest().getUrl() + "'", e);
                 }
                 if (!ignoreSAXException) {
                     throw new IOException(
                             "Failed parsing XML document '" + webResponse.getWebRequest().getUrl() + "'", e);
                 }
             }
         }
         catch (final ParserConfigurationException e) {
             if (LOG.isWarnEnabled()) {
                 if (null == webResponse) {
                     LOG.warn("Failed parsing XML empty document: " + e.getMessage(), e);
                 }
                 else {
                     LOG.warn("Failed parsing XML empty document '" + webResponse.getWebRequest().getUrl() + "'", e);
                 }
             }
         }
 
         for (Node node = node_; node != null; node = node.getNextSibling()) {
             XmlUtils.appendChild(this, this, node, handleXHTMLAsHTML);
         }
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void initialize() throws IOException {
         // nothing to do here
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public boolean hasCaseSensitiveTagNames() {
         return true;
     }
 
     /**
      * Returns the DOM representation of the XML content.
      * @return {@code null} if the content couldn't be parsed
      */
     public Document getXmlDocument() {
         if (node_ != null) {
             return node_.getOwnerDocument();
         }
         return null;
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public Node adoptNode(final Node source) {
         throw new UnsupportedOperationException("XmlPage.adoptNode is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public Attr createAttributeNS(final String namespaceURI, final String qualifiedName) {
         throw new UnsupportedOperationException("XmlPage.createAttributeNS is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public DomElement createElement(final String tagName) {
         return createElementNS(null, tagName);
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public DomElement createElementNS(final String namespaceURI, final String qualifiedName) {
         return new DomElement(namespaceURI, qualifiedName, this, new HashMap<>());
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public EntityReference createEntityReference(final String name) {
         throw new UnsupportedOperationException("XmlPage.createEntityReference is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public DomProcessingInstruction createProcessingInstruction(final String target, final String data) {
         return new DomProcessingInstruction(this, target, data);
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public String getDocumentURI() {
         throw new UnsupportedOperationException("XmlPage.getDocumentURI is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public DOMConfiguration getDomConfig() {
         throw new UnsupportedOperationException("XmlPage.getDomConfig is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public Element getElementById(final String elementId) {
         throw new UnsupportedOperationException("XmlPage.getElementById is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public DOMImplementation getImplementation() {
         throw new UnsupportedOperationException("XmlPage.getImplementation is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public String getInputEncoding() {
         throw new UnsupportedOperationException("XmlPage.getInputEncoding is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public boolean getStrictErrorChecking() {
         throw new UnsupportedOperationException("XmlPage.getStrictErrorChecking is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String getXmlEncoding() {
         return null;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public boolean getXmlStandalone() {
         return false;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String getXmlVersion() {
         return "1.0";
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public Node importNode(final Node importedNode, final boolean deep) {
         throw new UnsupportedOperationException("XmlPage.importNode is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public Node renameNode(final Node n, final String namespaceURI, final String qualifiedName) {
         throw new UnsupportedOperationException("XmlPage.renameNode is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public void setDocumentURI(final String documentURI) {
         throw new UnsupportedOperationException("XmlPage.setDocumentURI is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public void setStrictErrorChecking(final boolean strictErrorChecking) {
         throw new UnsupportedOperationException("XmlPage.setStrictErrorChecking is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public void setXmlStandalone(final boolean xmlStandalone) {
         throw new UnsupportedOperationException("XmlPage.setXmlStandalone is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public void setXmlVersion(final String xmlVersion) {
         throw new UnsupportedOperationException("XmlPage.setXmlVersion is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public Charset getCharset() {
         return UTF_8;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String getContentType() {
         return MimeType.APPLICATION_XML;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void setDocumentType(final DocumentType type) {
         super.setDocumentType(type);
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void setNodeValue(final String value) {
         // Default behavior is to do nothing, overridden in some subclasses
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void setPrefix(final String prefix) {
         // Empty.
     }
 }