/*
    * 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
    *
    *      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.apache.commons.io.channels;
  
  import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertFalse;
  import static org.junit.jupiter.api.Assertions.assertInstanceOf;
  import static org.junit.jupiter.api.Assertions.assertNotSame;
  import static org.junit.jupiter.api.Assertions.assertSame;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  import static org.mockito.Mockito.mock;
  import static org.mockito.Mockito.never;
  import static org.mockito.Mockito.times;
  import static org.mockito.Mockito.verify;
  import static org.mockito.Mockito.verifyNoInteractions;
  import static org.mockito.Mockito.verifyNoMoreInteractions;
  import static org.mockito.Mockito.when;
  
  import java.io.IOException;
  import java.nio.channels.AsynchronousChannel;
  import java.nio.channels.ByteChannel;
  import java.nio.channels.Channel;
  import java.nio.channels.ClosedChannelException;
  import java.nio.channels.FileChannel;
  import java.nio.channels.GatheringByteChannel;
  import java.nio.channels.InterruptibleChannel;
  import java.nio.channels.NetworkChannel;
  import java.nio.channels.ReadableByteChannel;
  import java.nio.channels.ScatteringByteChannel;
  import java.nio.channels.SeekableByteChannel;
  import java.nio.channels.WritableByteChannel;
  import java.nio.file.Path;
  import java.util.List;
  import java.util.stream.Stream;
  
  import org.apache.commons.io.FileUtils;
  import org.apache.commons.lang3.ClassUtils;
  import org.junit.jupiter.api.Test;
  import org.junit.jupiter.api.io.TempDir;
  import org.junit.jupiter.params.ParameterizedTest;
  import org.junit.jupiter.params.provider.MethodSource;
  
  /**
   * Tests {@link CloseShieldChannel}.
   */
  class CloseShieldChannelTest {
  
      /**
       * JRE {@link Channel} interfaces.
       */
      static Stream<Class<? extends Channel>> channelInterfaces() {
          // @formatter:off
          return Stream.of(
                  AsynchronousChannel.class,
                  ByteChannel.class,
                  Channel.class,
                  GatheringByteChannel.class,
                  InterruptibleChannel.class,
                  NetworkChannel.class,
                  ReadableByteChannel.class,
                  ScatteringByteChannel.class,
                  SeekableByteChannel.class,
                  WritableByteChannel.class);
          // @formatter:on
      }
  
      /**
       * Gets all interfaces implemented by the class {@link FileChannel}.
       */
      static List<Class<?>> fileChannelInterfaces() {
          return ClassUtils.getAllInterfaces(FileChannel.class);
      }
  
      @ParameterizedTest
      @MethodSource("channelInterfaces")
      void testCloseDoesNotCloseDelegate(final Class<? extends Channel> channelClass) throws Exception {
          final Channel channel = mock(channelClass);
          final Channel shield = CloseShieldChannel.wrap(channel);
          shield.close();
          verify(channel, never()).close();
      }
  
     @ParameterizedTest
     @MethodSource("channelInterfaces")
     void testCloseIsIdempotent(final Class<? extends Channel> channelClass) throws Exception {
         final Channel channel = mock(channelClass);
         final Channel shield = CloseShieldChannel.wrap(channel);
         shield.close();
         assertFalse(shield.isOpen());
         shield.close();
         assertFalse(shield.isOpen());
         verifyNoInteractions(channel);
     }
 
     @ParameterizedTest
     @MethodSource("channelInterfaces")
     void testCloseIsShielded(final Class<? extends Channel> channelInterface) throws Exception {
         final Channel channel = mock(channelInterface);
         when(channel.isOpen()).thenReturn(true, false, true, false);
         final Channel shield = CloseShieldChannel.wrap(channel);
         // Reflects delegate state initially
         assertTrue(shield.isOpen(), "isOpen reflects delegate state");
         assertFalse(shield.isOpen(), "isOpen reflects delegate state");
         verify(channel, times(2)).isOpen();
         shield.close();
         // Reflects shield state after close
         assertFalse(shield.isOpen(), "isOpen reflects shield state");
         assertFalse(shield.isOpen(), "isOpen reflects shield state");
         verify(channel, times(2)).isOpen();
     }
 
     @Test
     void testDoesNotDoubleWrap() {
         final ByteChannel channel = mock(ByteChannel.class);
         final ByteChannel shield1 = CloseShieldChannel.wrap(channel);
         final ByteChannel shield2 = CloseShieldChannel.wrap(shield1);
         assertSame(shield1, shield2);
     }
 
     @ParameterizedTest
     @MethodSource("channelInterfaces")
     void testEquals(final Class<? extends Channel> channelClass) throws Exception {
         final Channel channel = mock(channelClass);
         final Channel shield = CloseShieldChannel.wrap(channel);
         final Channel anotherShield = CloseShieldChannel.wrap(channel);
         assertTrue(shield.equals(shield), "reflexive");
         assertFalse(shield.equals(null), "null is not equal");
         assertFalse(shield.equals(channel), "shield not equal to delegate");
         assertTrue(shield.equals(anotherShield), "shields of same delegate are equal");
     }
 
     @Test
     void testGatheringByteChannelMethods() throws Exception {
         final GatheringByteChannel channel = mock(GatheringByteChannel.class);
         when(channel.isOpen()).thenReturn(true);
         final GatheringByteChannel shield = CloseShieldChannel.wrap(channel);
         // Before close write() should delegate
         when(channel.write(null, 0, 0)).thenReturn(42L);
         assertEquals(42, shield.write(null, 0, 0));
         verify(channel).write(null, 0, 0);
         // After close write() should throw ClosedChannelException
         shield.close();
         assertThrows(ClosedChannelException.class, () -> shield.write(null, 0, 0));
         verifyNoMoreInteractions(channel);
     }
 
     @ParameterizedTest
     @MethodSource("channelInterfaces")
     void testHashCode(final Class<? extends Channel> channelClass) throws Exception {
         final Channel channel = mock(channelClass);
         final Channel shield = CloseShieldChannel.wrap(channel);
         final Channel anotherShield = CloseShieldChannel.wrap(channel);
         assertEquals(shield.hashCode(), channel.hashCode(), "delegates hashCode");
         assertEquals(shield.hashCode(), anotherShield.hashCode(), "shields of same delegate have same hashCode");
     }
 
     @Test
     void testNetworkChannelMethods() throws Exception {
         final NetworkChannel channel = mock(NetworkChannel.class);
         when(channel.isOpen()).thenReturn(true);
         final NetworkChannel shield = CloseShieldChannel.wrap(channel);
         // Before close getOption(), setOption(), getLocalAddress() and bind() should delegate
         when(channel.getOption(null)).thenReturn("foo");
         when(channel.setOption(null, null)).thenReturn(channel);
         when(channel.getLocalAddress()).thenReturn(null);
         when(channel.bind(null)).thenReturn(channel);
         assertEquals("foo", shield.getOption(null));
         assertEquals(shield, shield.setOption(null, null));
         assertEquals(null, shield.getLocalAddress());
         assertEquals(shield, shield.bind(null));
         verify(channel).getOption(null);
         verify(channel).setOption(null, null);
         verify(channel).getLocalAddress();
         verify(channel).bind(null);
         // After close supportedOptions() should still work
         shield.close();
         assertDoesNotThrow(shield::supportedOptions);
         verify(channel).supportedOptions();
         // But the remaining methods should throw ClosedChannelException
         assertThrows(ClosedChannelException.class, () -> shield.setOption(null, null));
         assertThrows(ClosedChannelException.class, () -> shield.getOption(null));
         assertThrows(ClosedChannelException.class, shield::getLocalAddress);
         assertThrows(ClosedChannelException.class, () -> shield.bind(null));
         verifyNoMoreInteractions(channel);
     }
 
     @ParameterizedTest
     @MethodSource("channelInterfaces")
     void testPreservesInterfaces(final Class<? extends Channel> channelClass) {
         final Channel channel = mock(channelClass);
         final Channel shield = CloseShieldChannel.wrap(channel);
         assertNotSame(channel, shield);
         assertTrue(channelClass.isInstance(shield));
     }
 
     @Test
     void testReadableByteChannelMethods() throws Exception {
         final ReadableByteChannel channel = mock(ReadableByteChannel.class);
         when(channel.isOpen()).thenReturn(true);
         final ReadableByteChannel shield = CloseShieldChannel.wrap(channel);
         // Before close read() should delegate
         when(channel.read(null)).thenReturn(42);
         assertEquals(42, shield.read(null));
         verify(channel).read(null);
         // After close read() should throw ClosedChannelException
         shield.close();
         assertThrows(ClosedChannelException.class, () -> shield.read(null));
         verifyNoMoreInteractions(channel);
     }
 
     @Test
     void testScatteringByteChannelMethods() throws Exception {
         final ScatteringByteChannel channel = mock(ScatteringByteChannel.class);
         when(channel.isOpen()).thenReturn(true);
         final ScatteringByteChannel shield = CloseShieldChannel.wrap(channel);
         // Before close read() should delegate
         when(channel.read(null, 0, 0)).thenReturn(42L);
         assertEquals(42, shield.read(null, 0, 0));
         verify(channel).read(null, 0, 0);
         // After close read() should throw ClosedChannelException
         shield.close();
         assertThrows(ClosedChannelException.class, () -> shield.read(null, 0, 0));
         verifyNoMoreInteractions(channel);
     }
 
     @Test
     void testSeekableByteChannelMethods() throws Exception {
         final SeekableByteChannel channel = mock(SeekableByteChannel.class);
         when(channel.isOpen()).thenReturn(true);
         final SeekableByteChannel shield = CloseShieldChannel.wrap(channel);
         // Before close position() and size() should delegate
         when(channel.position()).thenReturn(42L);
         when(channel.size()).thenReturn(84L);
         assertEquals(42, shield.position());
         assertEquals(84, shield.size());
         verify(channel).position();
         verify(channel).size();
         // Before close position(long) and truncate(long) should delegate
         when(channel.position(21)).thenReturn(channel);
         when(channel.truncate(21)).thenReturn(channel);
         assertEquals(shield, shield.position(21));
         assertEquals(shield, shield.truncate(21));
         verify(channel).position(21);
         verify(channel).truncate(21);
         // After close position() should throw ClosedChannelException
         shield.close();
         assertThrows(ClosedChannelException.class, shield::position);
         assertThrows(ClosedChannelException.class, () -> shield.position(0));
         assertThrows(ClosedChannelException.class, shield::size);
         assertThrows(ClosedChannelException.class, () -> shield.truncate(0));
         verifyNoMoreInteractions(channel);
     }
 
     @ParameterizedTest
     @MethodSource("channelInterfaces")
     void testToString(final Class<? extends Channel> channelClass) throws Exception {
         final Channel channel = mock(channelClass);
         when(channel.toString()).thenReturn("MyChannel");
         final Channel shield = CloseShieldChannel.wrap(channel);
         final String shieldString = shield.toString();
         assertTrue(shieldString.contains("CloseShield"));
         assertTrue(shieldString.contains("MyChannel"));
     }
 
     @Test
     void testWrapFileChannel(final @TempDir Path tempDir) throws IOException {
         final Path testFile = tempDir.resolve("test.txt");
         FileUtils.touch(testFile.toFile());
         try (FileChannel channel = FileChannel.open(testFile); Channel shield = CloseShieldChannel.wrap(channel)) {
             fileChannelInterfaces().forEach(iface -> assertInstanceOf(iface, shield));
             // FileChannel is not an interface, so can not be implemented.
             assertFalse(shield instanceof FileChannel, "not FileChannel");
         }
     }
 
     @Test
     void testWritableByteChannelMethods() throws Exception {
         final WritableByteChannel channel = mock(WritableByteChannel.class);
         when(channel.isOpen()).thenReturn(true);
         final WritableByteChannel shield = CloseShieldChannel.wrap(channel);
         // Before close write() should delegate
         when(channel.write(null)).thenReturn(42);
         assertEquals(42, shield.write(null));
         verify(channel).write(null);
         // After close write() should throw ClosedChannelException
         shield.close();
         assertThrows(ClosedChannelException.class, () -> shield.write(null));
         verifyNoMoreInteractions(channel);
     }
 }