/*
    * 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.html;
  
  import org.htmlunit.SgmlPage;
  import org.w3c.dom.Attr;
  import org.w3c.dom.TypeInfo;
  
  /**
   * An attribute of an element. Attributes are stored in {@link HtmlElement},
   * but the XPath engine expects attributes to be in a {@link DomNode}.
   *
   * @author Denis N. Antonioli
   * @author David K. Taylor
   * @author Ahmed Ashour
   * @author Ronald Brill
   */
  public class DomAttr extends DomNamespaceNode implements Attr {
  
      private String value_;
      private boolean specified_;
  
      /**
       * Instantiate a new attribute.
       *
       * @param page the page that the attribute belongs to
       * @param namespaceURI the namespace that defines the attribute name (maybe {@code null})
       * @param qualifiedName the name of the attribute
       * @param value the value of the attribute
       * @param specified {@code true} if this attribute was explicitly given a value in the source document,
       *        or if the application changed the value of the attribute
       */
      public DomAttr(final SgmlPage page, final String namespaceURI, final String qualifiedName, final String value,
          final boolean specified) {
          super(namespaceURI, qualifiedName, page);
          value_ = normalizeValue(value);
          specified_ = specified;
      }
  
      private static String normalizeValue(final String value) {
          if (value != null && value.isEmpty()) {
              return DomElement.ATTRIBUTE_VALUE_EMPTY;
          }
          return value;
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public short getNodeType() {
          return ATTRIBUTE_NODE;
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public String getNodeName() {
          return getName();
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public String getNodeValue() {
          return getValue();
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public String getName() {
          return getQualifiedName();
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public String getValue() {
          return value_;
      }
  
      /**
      * {@inheritDoc}
      */
     @Override
     public void setNodeValue(final String value) {
         setValue(value);
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void setValue(final String value) {
         value_ = normalizeValue(value);
         specified_ = true;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public DomElement getOwnerElement() {
         return (DomElement) getParentNode();
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public boolean getSpecified() {
         return specified_;
     }
 
     /**
      * {@inheritDoc}
      * Not yet implemented.
      */
     @Override
     public TypeInfo getSchemaTypeInfo() {
         throw new UnsupportedOperationException("DomAttr.getSchemaTypeInfo is not yet implemented.");
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public boolean isId() {
         return DomElement.ID_ATTRIBUTE.equals(getNodeName());
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String toString() {
         return getClass().getSimpleName() + "[name=" + getNodeName() + " value=" + getNodeValue() + "]";
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String getCanonicalXPath() {
         final DomNode parent = getParentNode();
         if (parent == null) {
             return "/@" + getName();
         }
         return parent.getCanonicalXPath() + "/@" + getName();
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String getTextContent() {
         return getNodeValue();
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void setTextContent(final String textContent) {
         final DomElement owner = getOwnerElement();
         final boolean mappedElement = owner != null
                 && getOwnerDocument() instanceof HtmlPage
                 && (DomElement.NAME_ATTRIBUTE.equals(getName()) || DomElement.ID_ATTRIBUTE.equals(getName()));
 
         final HtmlPage htmlPage = mappedElement ? (HtmlPage) getPage() : null;
 
         if (mappedElement) {
             htmlPage.removeMappedElement(owner, false, false);
         }
         setValue(textContent);
         if (mappedElement) {
             htmlPage.addMappedElement(owner, false);
         }
     }
 }