/*
    * 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.javascript.host.html;
  
  import static org.htmlunit.BrowserVersionFeatures.HTMLCOLLECTION_NAMED_ITEM_ID_FIRST;
  
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.List;
  
  import org.htmlunit.BrowserVersion;
  import org.htmlunit.corejs.javascript.Scriptable;
  import org.htmlunit.html.DomElement;
  import org.htmlunit.html.DomNode;
  import org.htmlunit.html.HtmlForm;
  import org.htmlunit.html.HtmlInput;
  import org.htmlunit.javascript.JavaScriptEngine;
  import org.htmlunit.javascript.configuration.JsxClass;
  import org.htmlunit.javascript.configuration.JsxConstructor;
  import org.htmlunit.javascript.configuration.JsxFunction;
  import org.htmlunit.javascript.configuration.JsxGetter;
  import org.htmlunit.javascript.configuration.JsxSymbol;
  import org.htmlunit.javascript.host.dom.AbstractList;
  
  /**
   * An array of elements. Used for the element arrays returned by <code>document.all</code>,
   * <code>document.all.tags('x')</code>, <code>document.forms</code>, <code>window.frames</code>, etc.
   * Note that this class must not be used for collections that can be modified, for example
   * <code>map.areas</code> and <code>select.options</code>.
   * <br>
   * This class (like all classes in this package) is specific for the JavaScript engine.
   * Users of HtmlUnit shouldn't use it directly.
   *
   * @author Daniel Gredler
   * @author Marc Guillemot
   * @author Chris Erskine
   * @author Ahmed Ashour
   * @author Frank Danek
   * @author Ronald Brill
   *
   * @see <a href="https://developer.mozilla.org/en-US/docs/Web/API/HTMLCollection">MDN Documentation</a>
   */
  @JsxClass
  public class HTMLCollection extends AbstractList {
  
      /**
       * Creates an instance.
       */
      public HTMLCollection() {
          super();
      }
  
      /**
       * JavaScript constructor.
       */
      @JsxConstructor
      public void jsConstructor() {
          // nothing to do
      }
  
      /**
       * Creates an instance.
       * @param domNode the parent scope
       * @param attributeChangeSensitive indicates if the content of the collection may change when an attribute
       *        of a descendant node of domNode changes (attribute added, modified or removed)
       */
      public HTMLCollection(final DomNode domNode, final boolean attributeChangeSensitive) {
          super(domNode, attributeChangeSensitive, null);
      }
  
      /**
       * Constructs an instance with an initial cache value.
       * @param domNode the parent scope, on which we listen for changes
       * @param initialElements the initial content for the cache
       */
      HTMLCollection(final DomNode domNode, final List<DomNode> initialElements) {
          super(domNode, true, new ArrayList<>(initialElements));
      }
  
      private HTMLCollection(final DomNode domNode, final boolean attributeChangeSensitive,
              final List<DomNode> initialElements) {
          super(domNode, attributeChangeSensitive, new ArrayList<>(initialElements));
      }
  
      /**
       * Gets an empty collection.
       * @param domNode the DOM node
      * @return an empty collection
      */
     public static HTMLCollection emptyCollection(final DomNode domNode) {
         return new HTMLCollection(domNode, false, Collections.emptyList());
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     protected HTMLCollection create(final DomNode parentScope, final List<DomNode> initialElements) {
         return new HTMLCollection(parentScope, initialElements);
     }
 
     /**
      * Returns the {@code Symbol.iterator} function that allows iterating over this collection.
      * @return the Iterator symbol
      */
     @JsxSymbol
     public Scriptable iterator() {
         return JavaScriptEngine.newArrayIteratorTypeValues(getParentScope(), this);
     }
 
     /**
      * Returns the length.
      * @return the length
      */
     @JsxGetter
     @Override
     public final int getLength() {
         return super.getLength();
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     protected Object getWithPreemptionByName(final String name, final List<DomNode> elements) {
         final List<DomNode> matchingElements = new ArrayList<>();
         final boolean searchName = isGetWithPreemptionSearchName();
         for (final DomNode next : elements) {
             if (next instanceof DomElement element
                     && (searchName || next instanceof HtmlInput || next instanceof HtmlForm)) {
                 final String nodeName = element.getAttributeDirect(DomElement.NAME_ATTRIBUTE);
                 if (name.equals(nodeName)) {
                     matchingElements.add(next);
                 }
             }
         }
 
         if (matchingElements.isEmpty()) {
             return NOT_FOUND;
         }
 
         if (matchingElements.size() == 1) {
             return getScriptableForElement(matchingElements.get(0));
         }
 
         // many elements => build a sub collection
         final DomNode domNode = getDomNodeOrNull();
         final HTMLCollection collection = new HTMLCollection(domNode, matchingElements);
         collection.setAvoidObjectDetection(true);
         return collection;
     }
 
     /**
      * Returns whether {@link #getWithPreemption(String)} should search by name or not.
      * @return whether {@link #getWithPreemption(String)} should search by name or not
      */
     protected boolean isGetWithPreemptionSearchName() {
         return true;
     }
 
     /**
      * Returns the item or items corresponding to the specified index or key.
      * @param index the index or key corresponding to the element or elements to return
      * @return the element or elements corresponding to the specified index or key
      * @see <a href="https://developer.mozilla.org/en-US/docs/Web/API/HTMLCollection/item">MDN Documentation</a>
      */
     @JsxFunction
     public Object item(final Object index) {
         int idx = 0;
         final double doubleValue = JavaScriptEngine.toNumber(index);
         if (!Double.isNaN(doubleValue)) {
             idx = (int) doubleValue;
         }
 
         final Object object = get(idx, this);
         if (object == NOT_FOUND) {
             return null;
         }
         return object;
     }
 
     /**
      * Retrieves the item or items corresponding to the specified name (checks ids, and if
      * that does not work, then names).
      * @param name the name or id of the element or elements to return
      * @return the element or elements corresponding to the specified name or id
      * @see <a href="https://developer.mozilla.org/en-US/docs/Web/API/HTMLCollection/namedItem">MDN Documentation</a>
      */
     @JsxFunction
     public Scriptable namedItem(final String name) {
         final List<DomNode> elements = getElements();
         final BrowserVersion browserVersion = getBrowserVersion();
         if (browserVersion.hasFeature(HTMLCOLLECTION_NAMED_ITEM_ID_FIRST)) {
             for (final Object next : elements) {
                 if (next instanceof DomElement elem) {
                     final String id = elem.getId();
                     if (name.equals(id)) {
                         return getScriptableForElement(elem);
                     }
                 }
             }
         }
         for (final Object next : elements) {
             if (next instanceof DomElement elem) {
                 final String nodeName = elem.getAttributeDirect(DomElement.NAME_ATTRIBUTE);
                 if (name.equals(nodeName)) {
                     return getScriptableForElement(elem);
                 }
 
                 final String id = elem.getId();
                 if (name.equals(id)) {
                     return getScriptableForElement(elem);
                 }
             }
         }
         return null;
     }
 }