/*
    * Copyright 2025 The Netty Project
    *
    * The Netty Project 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:
    *
    *   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 io.netty.handler.ssl;
  
  import io.netty.util.internal.PlatformDependent;
  
  import javax.net.ssl.SSLParameters;
  import java.lang.invoke.MethodHandle;
  import java.lang.invoke.MethodHandles;
  import java.lang.invoke.MethodType;
  import java.security.AccessController;
  import java.security.PrivilegedAction;
  
  final class OpenSslParametersUtil {
  
      private static final MethodHandle GET_NAMED_GROUPS;
      private static final MethodHandle SET_NAMED_GROUPS;
  
      static {
          MethodHandle getNamedGroups = null;
          MethodHandle setNamedGroups = null;
          if (PlatformDependent.javaVersion() >= 20) {
              final MethodHandles.Lookup lookup = MethodHandles.lookup();
              getNamedGroups = obtainHandle(lookup, "getNamedGroups",
                      MethodType.methodType(String[].class));
              setNamedGroups = obtainHandle(lookup, "setNamedGroups",
                      MethodType.methodType(void.class, String[].class));
          }
          GET_NAMED_GROUPS = getNamedGroups;
          SET_NAMED_GROUPS = setNamedGroups;
      }
  
      private static MethodHandle obtainHandle(final MethodHandles.Lookup lookup,
                                               final String methodName, final MethodType type) {
          return AccessController.doPrivileged((PrivilegedAction<MethodHandle>) () -> {
              try {
                  return lookup.findVirtual(SSLParameters.class, methodName, type);
              } catch (UnsupportedOperationException | SecurityException |
                       NoSuchMethodException | IllegalAccessException e) {
                  // Just ignore it.
                  return null;
              }
          });
      }
  
      static String[] getNamesGroups(SSLParameters parameters) {
          if (GET_NAMED_GROUPS == null) {
              return null;
          }
          try {
              return (String[]) GET_NAMED_GROUPS.invoke(parameters);
          } catch (Throwable t) {
              // Just ignore it.
              return null;
          }
      }
  
      static void setNamesGroups(SSLParameters parameters, String[] names) {
          if (SET_NAMED_GROUPS == null) {
              return;
          }
          try {
              SET_NAMED_GROUPS.invoke(parameters, names);
          } catch (Throwable ignore) {
              // Ignore
          }
      }
  
      private OpenSslParametersUtil() { }
  }