/*
    * 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:
    *
    *   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 io.netty.buffer;
  
  import io.netty.util.Recycler;
  import io.netty.util.internal.PlatformDependent;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.nio.ByteBuffer;
  import java.nio.channels.ClosedChannelException;
  import java.nio.channels.GatheringByteChannel;
  import java.nio.channels.ScatteringByteChannel;
  
  final class PooledUnsafeDirectByteBuf extends PooledByteBuf<ByteBuffer> {
      private static final Recycler<PooledUnsafeDirectByteBuf> RECYCLER = new Recycler<PooledUnsafeDirectByteBuf>() {
          @Override
          protected PooledUnsafeDirectByteBuf newObject(Handle handle) {
              return new PooledUnsafeDirectByteBuf(handle, 0);
          }
      };
  
      static PooledUnsafeDirectByteBuf newInstance(int maxCapacity) {
          PooledUnsafeDirectByteBuf buf = RECYCLER.get();
          buf.reuse(maxCapacity);
          return buf;
      }
  
      private long memoryAddress;
  
      private PooledUnsafeDirectByteBuf(Recycler.Handle recyclerHandle, int maxCapacity) {
          super(recyclerHandle, maxCapacity);
      }
  
      @Override
      void init(PoolChunk<ByteBuffer> chunk, long handle, int offset, int length, int maxLength,
                PoolThreadCache cache) {
          super.init(chunk, handle, offset, length, maxLength, cache);
          initMemoryAddress();
      }
  
      @Override
      void initUnpooled(PoolChunk<ByteBuffer> chunk, int length) {
          super.initUnpooled(chunk, length);
          initMemoryAddress();
      }
  
      private void initMemoryAddress() {
          memoryAddress = PlatformDependent.directBufferAddress(memory) + offset;
      }
  
      @Override
      protected ByteBuffer newInternalNioBuffer(ByteBuffer memory) {
          return memory.duplicate();
      }
  
      @Override
      public boolean isDirect() {
          return true;
      }
  
      @Override
      protected byte _getByte(int index) {
          return UnsafeByteBufUtil.getByte(addr(index));
      }
  
      @Override
      protected short _getShort(int index) {
          return UnsafeByteBufUtil.getShort(addr(index));
      }
  
      @Override
      protected int _getUnsignedMedium(int index) {
          return UnsafeByteBufUtil.getUnsignedMedium(addr(index));
      }
  
      @Override
      protected int _getInt(int index) {
          return UnsafeByteBufUtil.getInt(addr(index));
      }
  
      @Override
      protected long _getLong(int index) {
          return UnsafeByteBufUtil.getLong(addr(index));
     }
 
     @Override
     public ByteBuf getBytes(int index, ByteBuf dst, int dstIndex, int length) {
         UnsafeByteBufUtil.getBytes(this, addr(index), index, dst, dstIndex, length);
         return this;
     }
 
     @Override
     public ByteBuf getBytes(int index, byte[] dst, int dstIndex, int length) {
         UnsafeByteBufUtil.getBytes(this, addr(index), index, dst, dstIndex, length);
         return this;
     }
 
     @Override
     public ByteBuf getBytes(int index, ByteBuffer dst) {
         UnsafeByteBufUtil.getBytes(this, addr(index), index, dst);
         return this;
     }
 
     @Override
     public ByteBuf readBytes(ByteBuffer dst) {
         int length = dst.remaining();
         checkReadableBytes(length);
         getBytes(readerIndex, dst);
         readerIndex += length;
         return this;
     }
 
     @Override
     public ByteBuf getBytes(int index, OutputStream out, int length) throws IOException {
         UnsafeByteBufUtil.getBytes(this, addr(index), index, out, length);
         return this;
     }
 
     @Override
     public int getBytes(int index, GatheringByteChannel out, int length) throws IOException {
         return getBytes(index, out, length, false);
     }
 
     private int getBytes(int index, GatheringByteChannel out, int length, boolean internal) throws IOException {
         checkIndex(index, length);
         if (length == 0) {
             return 0;
         }
 
         ByteBuffer tmpBuf;
         if (internal) {
             tmpBuf = internalNioBuffer();
         } else {
             tmpBuf = memory.duplicate();
         }
         index = idx(index);
         tmpBuf.clear().position(index).limit(index + length);
         return out.write(tmpBuf);
     }
 
     @Override
     public int readBytes(GatheringByteChannel out, int length)
             throws IOException {
         checkReadableBytes(length);
         int readBytes = getBytes(readerIndex, out, length, true);
         readerIndex += readBytes;
         return readBytes;
     }
 
     @Override
     protected void _setByte(int index, int value) {
         UnsafeByteBufUtil.setByte(addr(index), (byte) value);
     }
 
     @Override
     protected void _setShort(int index, int value) {
         UnsafeByteBufUtil.setShort(addr(index), value);
     }
 
     @Override
     protected void _setMedium(int index, int value) {
         UnsafeByteBufUtil.setMedium(addr(index), value);
     }
 
     @Override
     protected void _setInt(int index, int value) {
         UnsafeByteBufUtil.setInt(addr(index), value);
     }
 
     @Override
     protected void _setLong(int index, long value) {
         UnsafeByteBufUtil.setLong(addr(index), value);
     }
 
     @Override
     public ByteBuf setBytes(int index, ByteBuf src, int srcIndex, int length) {
         UnsafeByteBufUtil.setBytes(this, addr(index), index, src, srcIndex, length);
         return this;
     }
 
     @Override
     public ByteBuf setBytes(int index, byte[] src, int srcIndex, int length) {
         UnsafeByteBufUtil.setBytes(this, addr(index), index, src, srcIndex, length);
         return this;
     }
 
     @Override
     public ByteBuf setBytes(int index, ByteBuffer src) {
         UnsafeByteBufUtil.setBytes(this, addr(index), index, src);
         return this;
     }
 
     @Override
     public int setBytes(int index, InputStream in, int length) throws IOException {
         return UnsafeByteBufUtil.setBytes(this, addr(index), index, in, length);
     }
 
     @Override
     public int setBytes(int index, ScatteringByteChannel in, int length) throws IOException {
         checkIndex(index, length);
         ByteBuffer tmpBuf = internalNioBuffer();
         index = idx(index);
         tmpBuf.clear().position(index).limit(index + length);
         try {
             return in.read(tmpBuf);
         } catch (ClosedChannelException ignored) {
             return -1;
         }
     }
 
     @Override
     public ByteBuf copy(int index, int length) {
         return UnsafeByteBufUtil.copy(this, addr(index), index, length);
     }
 
     @Override
     public int nioBufferCount() {
         return 1;
     }
 
     @Override
     public ByteBuffer[] nioBuffers(int index, int length) {
         return new ByteBuffer[] { nioBuffer(index, length) };
     }
 
     @Override
     public ByteBuffer nioBuffer(int index, int length) {
         checkIndex(index, length);
         index = idx(index);
         return ((ByteBuffer) memory.duplicate().position(index).limit(index + length)).slice();
     }
 
     @Override
     public ByteBuffer internalNioBuffer(int index, int length) {
         checkIndex(index, length);
         index = idx(index);
         return (ByteBuffer) internalNioBuffer().clear().position(index).limit(index + length);
     }
 
     @Override
     public boolean hasArray() {
         return false;
     }
 
     @Override
     public byte[] array() {
         throw new UnsupportedOperationException("direct buffer");
     }
 
     @Override
     public int arrayOffset() {
         throw new UnsupportedOperationException("direct buffer");
     }
 
     @Override
     public boolean hasMemoryAddress() {
         return true;
     }
 
     @Override
     public long memoryAddress() {
         ensureAccessible();
         return memoryAddress;
     }
 
     private long addr(int index) {
         return memoryAddress + index;
     }
 
     @Override
     protected Recycler<?> recycler() {
         return RECYCLER;
     }
 
     @Override
     protected SwappedByteBuf newSwappedByteBuf() {
         if (PlatformDependent.isUnaligned()) {
             // Only use if unaligned access is supported otherwise there is no gain.
             return new UnsafeDirectSwappedByteBuf(this);
         }
         return super.newSwappedByteBuf();
     }
 
     @Override
     public ByteBuf setZero(int index, int length) {
         checkIndex(index, length);
         UnsafeByteBufUtil.setZero(addr(index), length);
         return this;
     }
 
     @Override
     public ByteBuf writeZero(int length) {
         ensureWritable(length);
         int wIndex = writerIndex;
         UnsafeByteBufUtil.setZero(addr(wIndex), length);
         writerIndex = wIndex + length;
         return this;
     }
 }