/*
    * Copyright 2013 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.buffer;
  
  import io.netty.util.ResourceLeakDetector;
  import io.netty.util.ResourceLeakTracker;
  import io.netty.util.internal.ObjectUtil;
  
  import java.nio.ByteOrder;
  
  class SimpleLeakAwareByteBuf extends WrappedByteBuf {
  
      /**
       * This object's is associated with the {@link ResourceLeakTracker}. When {@link ResourceLeakTracker#close(Object)}
       * is called this object will be used as the argument. It is also assumed that this object is used when
       * {@link ResourceLeakDetector#track(Object)} is called to create {@link #leak}.
       */
      private final ByteBuf trackedByteBuf;
      final ResourceLeakTracker<ByteBuf> leak;
  
      SimpleLeakAwareByteBuf(ByteBuf wrapped, ByteBuf trackedByteBuf, ResourceLeakTracker<ByteBuf> leak) {
          super(wrapped);
          this.trackedByteBuf = ObjectUtil.checkNotNull(trackedByteBuf, "trackedByteBuf");
          this.leak = ObjectUtil.checkNotNull(leak, "leak");
      }
  
      SimpleLeakAwareByteBuf(ByteBuf wrapped, ResourceLeakTracker<ByteBuf> leak) {
          this(wrapped, wrapped, leak);
      }
  
      @Override
      public ByteBuf slice() {
          return newSharedLeakAwareByteBuf(super.slice());
      }
  
      @Override
      public ByteBuf retainedSlice() {
          return unwrappedDerived(super.retainedSlice());
      }
  
      @Override
      public ByteBuf retainedSlice(int index, int length) {
          return unwrappedDerived(super.retainedSlice(index, length));
      }
  
      @Override
      public ByteBuf retainedDuplicate() {
          return unwrappedDerived(super.retainedDuplicate());
      }
  
      @Override
      public ByteBuf readRetainedSlice(int length) {
          return unwrappedDerived(super.readRetainedSlice(length));
      }
  
      @Override
      public ByteBuf slice(int index, int length) {
          return newSharedLeakAwareByteBuf(super.slice(index, length));
      }
  
      @Override
      public ByteBuf duplicate() {
          return newSharedLeakAwareByteBuf(super.duplicate());
      }
  
      @Override
      public ByteBuf readSlice(int length) {
          return newSharedLeakAwareByteBuf(super.readSlice(length));
      }
  
      @Override
      public ByteBuf asReadOnly() {
          return newSharedLeakAwareByteBuf(super.asReadOnly());
      }
  
      @Override
      public ByteBuf touch() {
          return this;
      }
  
      @Override
      public ByteBuf touch(Object hint) {
          return this;
      }
  
     @Override
     public boolean release() {
         if (super.release()) {
             closeLeak();
             return true;
         }
         return false;
     }
 
     @Override
     public boolean release(int decrement) {
         if (super.release(decrement)) {
             closeLeak();
             return true;
         }
         return false;
     }
 
     private void closeLeak() {
         // Close the ResourceLeakTracker with the tracked ByteBuf as argument. This must be the same that was used when
         // calling DefaultResourceLeak.track(...).
         boolean closed = leak.close(trackedByteBuf);
         assert closed;
     }
 
     @Override
     public ByteBuf order(ByteOrder endianness) {
         if (order() == endianness) {
             return this;
         } else {
             return newSharedLeakAwareByteBuf(super.order(endianness));
         }
     }
 
     private ByteBuf unwrappedDerived(ByteBuf derived) {
         // We only need to unwrap SwappedByteBuf implementations as these will be the only ones that may end up in
         // the AbstractLeakAwareByteBuf implementations beside slices / duplicates and "real" buffers.
         ByteBuf unwrappedDerived = unwrapSwapped(derived);
 
         if (unwrappedDerived instanceof AbstractPooledDerivedByteBuf) {
             // Update the parent to point to this buffer so we correctly close the ResourceLeakTracker.
             ((AbstractPooledDerivedByteBuf) unwrappedDerived).parent(this);
 
             // force tracking of derived buffers (see issue #13414)
             return newLeakAwareByteBuf(derived, AbstractByteBuf.leakDetector.trackForcibly(derived));
         }
         return newSharedLeakAwareByteBuf(derived);
     }
 
     @SuppressWarnings("deprecation")
     private static ByteBuf unwrapSwapped(ByteBuf buf) {
         if (buf instanceof SwappedByteBuf) {
             do {
                 buf = buf.unwrap();
             } while (buf instanceof SwappedByteBuf);
 
             return buf;
         }
         return buf;
     }
 
     private SimpleLeakAwareByteBuf newSharedLeakAwareByteBuf(
             ByteBuf wrapped) {
         return newLeakAwareByteBuf(wrapped, trackedByteBuf, leak);
     }
 
     private SimpleLeakAwareByteBuf newLeakAwareByteBuf(
             ByteBuf wrapped, ResourceLeakTracker<ByteBuf> leakTracker) {
         return newLeakAwareByteBuf(wrapped, wrapped, leakTracker);
     }
 
     protected SimpleLeakAwareByteBuf newLeakAwareByteBuf(
             ByteBuf buf, ByteBuf trackedByteBuf, ResourceLeakTracker<ByteBuf> leakTracker) {
         return new SimpleLeakAwareByteBuf(buf, trackedByteBuf, leakTracker);
     }
 }