/*
    * 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;
  
  import java.util.Set;
  
  import org.htmlunit.Page;
  import org.htmlunit.WebWindow;
  import org.htmlunit.corejs.javascript.Context;
  import org.htmlunit.corejs.javascript.Function;
  import org.htmlunit.corejs.javascript.FunctionObject;
  import org.htmlunit.corejs.javascript.Scriptable;
  import org.htmlunit.corejs.javascript.TopLevel;
  import org.htmlunit.corejs.javascript.VarScope;
  import org.htmlunit.javascript.AbstractJavaScriptEngine;
  import org.htmlunit.javascript.HtmlUnitContextFactory;
  import org.htmlunit.javascript.JavaScriptEngine;
  import org.htmlunit.javascript.PostponedAction;
  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.JsxSetter;
  import org.htmlunit.javascript.host.event.Event;
  import org.htmlunit.javascript.host.event.EventTarget;
  import org.htmlunit.javascript.host.event.MessageEvent;
  import org.htmlunit.util.UrlUtils;
  
  /**
   * JavaScript host object for {@code BroadcastChannel}.
   *
   * @author Ronald Brill
   *
   * @see <a href="https://developer.mozilla.org/en-US/docs/Web/API/BroadcastChannel">MDN Documentation</a>
   */
  @JsxClass
  public class BroadcastChannel extends EventTarget {
  
      private String name_;
  
      /**
       * Creates an instance of this object.
       *
       * @param cx the current context
       * @param scope the scope
       * @param args the constructor arguments
       * @param ctorObj the function object
       * @param inNewExpr whether invoked via {@code new}
       * @return the new {@code BroadcastChannel} instance
       */
      @JsxConstructor
      public static BroadcastChannel jsConstructor(final Context cx, final VarScope scope,
              final Object[] args, final Function ctorObj, final boolean inNewExpr) {
          if (args.length < 1 || JavaScriptEngine.isUndefined(args[0])) {
              throw JavaScriptEngine.typeError("BroadcastChannel constructor requires a channel name argument");
          }
  
          final BroadcastChannel broadcastChannel = new BroadcastChannel();
          final Window window = getWindow(ctorObj);
          broadcastChannel.setParentScope(getTopLevelScope(scope));
          broadcastChannel.setPrototype(((FunctionObject) ctorObj).getClassPrototype());
  
          broadcastChannel.name_ = JavaScriptEngine.toString(args[0]);
  
          final Set<BroadcastChannel> broadcastChannels = window.getWebWindow().getWebClient().getBroadcastChannels();
          synchronized (broadcastChannels) {
              broadcastChannels.add(broadcastChannel);
          }
  
          return broadcastChannel;
      }
  
      /**
       * Returns the channel name.
       *
       * @return the channel name
       */
      @JsxGetter
      public String getName() {
          return name_;
      }
  
      /**
       * Returns the {@code onmessage} event handler.
       *
       * @return the {@code onmessage} event handler
       */
     @JsxGetter
     public Function getOnmessage() {
         return getEventListenersContainer().getEventHandler(Event.TYPE_MESSAGE);
     }
 
     /**
      * Sets the {@code onmessage} event handler.
      *
      * @param onmessage the {@code onmessage} event handler
      */
     @JsxSetter
     public void setOnmessage(final Object onmessage) {
         getEventListenersContainer().setEventHandler(Event.TYPE_MESSAGE, onmessage);
     }
 
     /**
      * Returns the {@code onmessageerror} event handler.
      *
      * @return the {@code onmessageerror} event handler
      */
     @JsxGetter
     public Function getOnmessageerror() {
         return getEventListenersContainer().getEventHandler("messageerror");
     }
 
     /**
      * Sets the {@code onmessageerror} event handler.
      *
      * @param onmessageerror the {@code onmessageerror} event handler
      */
     @JsxSetter
     public void setOnmessageerror(final Object onmessageerror) {
         getEventListenersContainer().setEventHandler("messageerror", onmessageerror);
     }
 
     /**
      * Posts a message to all other {@code BroadcastChannel} objects with the same name.
      *
      * @param message the message to send
      * @see <a href="https://developer.mozilla.org/en-US/docs/Web/API/BroadcastChannel/postMessage">MDN Documentation</a>
      */
     @JsxFunction
     public void postMessage(final Object message) {
         if (name_ == null) {
             return;
         }
 
         final Window w = getWindow();
         final WebWindow webWindow = w.getWebWindow();
         final Page page = webWindow.getEnclosedPage();
         final java.net.URL currentURL = page.getUrl();
         final String origin = currentURL.getProtocol() + "://" + currentURL.getHost() + ':' + currentURL.getPort();
 
         final AbstractJavaScriptEngine<?> jsEngine = webWindow.getWebClient().getJavaScriptEngine();
 
         final Set<BroadcastChannel> broadcastChannels = webWindow.getWebClient().getBroadcastChannels();
 
         synchronized (broadcastChannels) {
             for (final BroadcastChannel channel : broadcastChannels) {
                 if (channel != this && name_.equals(channel.name_)) {
                     final Window channelWindow = channel.getWindow();
                     final Page channelPage = channelWindow.getWebWindow().getEnclosedPage();
 
                     if (UrlUtils.isSameOrigin(currentURL, channelPage.getUrl())) {
                         final TopLevel scope = getTopLevelScope(channelWindow.getParentScope());
                         final Scriptable ports = JavaScriptEngine.newArray(scope, 0);
 
                         final MessageEvent event = new MessageEvent();
                         event.initMessageEvent(Event.TYPE_MESSAGE, false, false, message, origin, "", null, ports);
                         event.setParentScope(scope);
                         event.setPrototype(channelWindow.getPrototype(event.getClass()));
 
                         final PostponedAction action =
                                 new PostponedAction(channelPage, "BroadcastChannel.postMessage") {
                                 @Override
                                 public void execute() {
                                     final HtmlUnitContextFactory cf = jsEngine.getContextFactory();
                                     cf.call(cx -> channel.dispatchEvent(event));
                                 }
                             };
                         jsEngine.addPostponedAction(action);
                     }
                 }
             }
         }
     }
 
     /**
      * Closes this {@code BroadcastChannel}, indicating it will no longer receive messages
      * and allowing it to be garbage collected.
      */
     @JsxFunction
     public void close() {
         final Set<BroadcastChannel> broadcastChannels =
                 getWindow().getWebWindow().getWebClient().getBroadcastChannels();
         synchronized (broadcastChannels) {
             broadcastChannels.remove(this);
         }
         name_ = null;
     }
 }