/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF 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.apache.fory.io;

import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectStreamClass;
import java.io.StreamCorruptedException;
import java.lang.reflect.Proxy;

// Derived from
// https://github.com/apache/commons-io/blob/5168fa5e9de9dd2ff6ace3f34226397a4faebc14/src/main/java/org/apache/commons/io/input/ClassLoaderObjectInputStream.java.

/**
 * A special ObjectInputStream that loads a class based on a specified <code>ClassLoader</code>
 * rather than the system default.
 *
 * <p>This is useful in dynamic container environments.
 */
public class ClassLoaderObjectInputStream extends ObjectInputStream {

  /** The class loader to use. */
  private final ClassLoader classLoader;

  /**
   * Constructs a new ClassLoaderObjectInputStream.
   *
   * @param classLoader the ClassLoader from which classes should be loaded
   * @param inputStream the InputStream to work on
   * @throws IOException in case of an I/O error
   * @throws StreamCorruptedException if the stream is corrupted
   */
  public ClassLoaderObjectInputStream(ClassLoader classLoader, InputStream inputStream)
      throws IOException, StreamCorruptedException {
    super(inputStream);
    this.classLoader = classLoader;
  }

  /**
   * Resolve a class specified by the descriptor using the specified ClassLoader or the super
   * ClassLoader.
   *
   * @param objectStreamClass descriptor of the class
   * @return the Class object described by the ObjectStreamClass
   * @throws IOException in case of an I/O error
   * @throws ClassNotFoundException if the Class cannot be found
   */
  @Override
  protected Class<?> resolveClass(ObjectStreamClass objectStreamClass)
      throws IOException, ClassNotFoundException {
    Class<?> clazz = Class.forName(objectStreamClass.getName(), false, classLoader);
    if (clazz != null) {
      // the classloader knows of the class
      return clazz;
    } else {
      // classloader knows not of class, let the super classloader do it
      return super.resolveClass(objectStreamClass);
    }
  }

  /**
   * Create a proxy class that implements the specified interfaces using the specified ClassLoader
   * or the super ClassLoader.
   *
   * @param interfaces the interfaces to implement
   * @return a proxy class implementing the interfaces
   * @throws IOException in case of an I/O error
   * @throws ClassNotFoundException if the Class cannot be found
   * @see ObjectInputStream#resolveProxyClass(String[])
   * @since 2.1
   */
  @Override
  protected Class<?> resolveProxyClass(String[] interfaces)
      throws IOException, ClassNotFoundException {
    Class<?>[] interfaceClasses = new Class[interfaces.length];
    for (int i = 0; i < interfaces.length; i++) {
      interfaceClasses[i] = Class.forName(interfaces[i], false, classLoader);
    }
    try {
      return Proxy.getProxyClass(classLoader, interfaceClasses);
    } catch (IllegalArgumentException e) {
      return super.resolveProxyClass(interfaces);
    }
  }
}
