code: // Licensed to the Software Freedom Conservancy (SFC) under one
  // or more contributor license agreements.  See the NOTICE file
  // distributed with this work for additional information
  // regarding copyright ownership.  The SFC 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 org.openqa.selenium.devtools.idealized;
  
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Map;
  import java.util.Set;
  import java.util.function.Consumer;
  import org.openqa.selenium.devtools.Command;
  import org.openqa.selenium.devtools.DevTools;
  import org.openqa.selenium.devtools.Event;
  import org.openqa.selenium.devtools.idealized.target.model.SessionID;
  import org.openqa.selenium.internal.Require;
  
  public abstract class Javascript<SCRIPTID, BINDINGCALLED> {
  
    private final DevTools devtools;
    private final Map<SessionID, Map<String, ScriptId>> pinnedScripts = new HashMap<>();
    private final Set<String> bindings = new HashSet<>();
  
    public Javascript(DevTools devtools) {
      this.devtools = Require.nonNull("DevTools", devtools);
    }
  
    public void disable() {
      devtools.send(disableRuntime());
      devtools.send(disablePage());
  
      pinnedScripts.forEach(
          (sessionID, scriptIdMap) ->
              scriptIdMap
                  .values()
                  .forEach(id -> removeScriptToEvaluateOnNewDocument(id.getActualId())));
  
      pinnedScripts.clear();
    }
  
    protected abstract Command<Void> disablePage();
  
    protected abstract Command<Void> disableRuntime();
  
    public ScriptId pin(String exposeScriptAs, String script) {
      Require.nonNull("Script name", exposeScriptAs);
      Require.nonNull("Script", script);
  
      if (pinnedScripts.containsKey(devtools.getCdpSession())) {
        Map<String, ScriptId> scripts = pinnedScripts.get(devtools.getCdpSession());
        if (scripts.containsKey(script)) {
          return scripts.get(script);
        }
      }
  
      devtools.send(enableRuntime());
  
      devtools.send(doAddJsBinding(exposeScriptAs));
  
      devtools.send(enablePage());
  
      SCRIPTID id = devtools.send(addScriptToEvaluateOnNewDocument(script));
      ScriptId scriptId = new ScriptId(id);
  
      Map<String, ScriptId> scripts =
          pinnedScripts.getOrDefault(devtools.getCdpSession(), new HashMap<>());
      scripts.put(script, scriptId);
      pinnedScripts.put(devtools.getCdpSession(), scripts);
  
      return scriptId;
    }
  
    public void addBindingCalledListener(Consumer<String> listener) {
      Require.nonNull("Listener", listener);
  
      devtools.send(enableRuntime());
  
      devtools.addListener(
          bindingCalledEvent(),
          event -> {
            String payload = extractPayload(event);
            listener.accept(payload);
          });
    }
  
    public void addJsBinding(String scriptName) {
      Require.nonNull("Script name", scriptName);
      bindings.add(scriptName);
      doAddJsBinding(scriptName);
    }
  
    public void removeJsBinding(String scriptName) {
      Require.nonNull("Script name", scriptName);
      bindings.remove(scriptName);
      doRemoveJsBinding(scriptName);
    }
  
    protected abstract Command<Void> enableRuntime();
  
    protected abstract Command<Void> doAddJsBinding(String scriptName);
  
    protected abstract Command<Void> doRemoveJsBinding(String scriptName);
  
    protected abstract Command<Void> enablePage();
  
    protected abstract Command<SCRIPTID> addScriptToEvaluateOnNewDocument(String script);
  
    protected abstract Command<Void> removeScriptToEvaluateOnNewDocument(SCRIPTID id);
  
    protected abstract Event<BINDINGCALLED> bindingCalledEvent();
  
    protected abstract String extractPayload(BINDINGCALLED event);
  }
  