/*
    * Copyright 2016 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.channel.kqueue;
  
  import io.netty.buffer.ByteBufAllocator;
  import io.netty.channel.ChannelException;
  import io.netty.channel.ChannelOption;
  import io.netty.channel.DefaultChannelConfig;
  import io.netty.channel.MessageSizeEstimator;
  import io.netty.channel.RecvByteBufAllocator;
  import io.netty.channel.WriteBufferWaterMark;
  import io.netty.channel.unix.IntegerUnixChannelOption;
  import io.netty.channel.unix.RawUnixChannelOption;
  import io.netty.util.internal.UnstableApi;
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.util.Map;
  
  import static io.netty.channel.kqueue.KQueueChannelOption.RCV_ALLOC_TRANSPORT_PROVIDES_GUESS;
  import static io.netty.channel.unix.Limits.SSIZE_MAX;
  import static java.lang.Math.min;
  
  @UnstableApi
  public class KQueueChannelConfig extends DefaultChannelConfig {
      private volatile boolean transportProvidesGuess;
      private volatile long maxBytesPerGatheringWrite = SSIZE_MAX;
  
      KQueueChannelConfig(AbstractKQueueChannel channel) {
          super(channel);
      }
  
      KQueueChannelConfig(AbstractKQueueChannel channel, RecvByteBufAllocator recvByteBufAllocator) {
          super(channel, recvByteBufAllocator);
      }
  
      @Override
      @SuppressWarnings("deprecation")
      public Map<ChannelOption<?>, Object> getOptions() {
          return getOptions(super.getOptions(), RCV_ALLOC_TRANSPORT_PROVIDES_GUESS);
      }
  
      @SuppressWarnings("unchecked")
      @Override
      public <T> T getOption(ChannelOption<T> option) {
          if (option == RCV_ALLOC_TRANSPORT_PROVIDES_GUESS) {
              return (T) Boolean.valueOf(getRcvAllocTransportProvidesGuess());
          }
          try {
              if (option instanceof IntegerUnixChannelOption) {
                  IntegerUnixChannelOption opt = (IntegerUnixChannelOption) option;
                  return (T) Integer.valueOf(((AbstractKQueueChannel) channel).socket.getIntOpt(
                          opt.level(), opt.optname()));
              }
              if (option instanceof RawUnixChannelOption) {
                  RawUnixChannelOption opt = (RawUnixChannelOption) option;
                  ByteBuffer out = ByteBuffer.allocate(opt.length());
                  ((AbstractKQueueChannel) channel).socket.getRawOpt(opt.level(), opt.optname(), out);
                  return (T) out.flip();
              }
          } catch (IOException e) {
              throw new ChannelException(e);
          }
          return super.getOption(option);
      }
  
      @Override
      public <T> boolean setOption(ChannelOption<T> option, T value) {
          validate(option, value);
  
          if (option == RCV_ALLOC_TRANSPORT_PROVIDES_GUESS) {
              setRcvAllocTransportProvidesGuess((Boolean) value);
          } else {
              try {
                  if (option instanceof IntegerUnixChannelOption) {
                      IntegerUnixChannelOption opt = (IntegerUnixChannelOption) option;
                      ((AbstractKQueueChannel) channel).socket.setIntOpt(opt.level(), opt.optname(), (Integer) value);
                      return true;
                  } else if (option instanceof RawUnixChannelOption) {
                      RawUnixChannelOption opt = (RawUnixChannelOption) option;
                      ((AbstractKQueueChannel) channel).socket.setRawOpt(opt.level(), opt.optname(), (ByteBuffer) value);
                      return true;
                  }
              } catch (IOException e) {
                  throw new ChannelException(e);
              }
             return super.setOption(option, value);
         }
 
         return true;
     }
 
     /**
      * If this is {@code true} then the {@link RecvByteBufAllocator.Handle#guess()} will be overridden to always attempt
      * to read as many bytes as kqueue says are available.
      */
     public KQueueChannelConfig setRcvAllocTransportProvidesGuess(boolean transportProvidesGuess) {
         this.transportProvidesGuess = transportProvidesGuess;
         return this;
     }
 
     /**
      * If this is {@code true} then the {@link RecvByteBufAllocator.Handle#guess()} will be overridden to always attempt
      * to read as many bytes as kqueue says are available.
      */
     public boolean getRcvAllocTransportProvidesGuess() {
         return transportProvidesGuess;
     }
 
     @Override
     public KQueueChannelConfig setConnectTimeoutMillis(int connectTimeoutMillis) {
         super.setConnectTimeoutMillis(connectTimeoutMillis);
         return this;
     }
 
     @Override
     @Deprecated
     public KQueueChannelConfig setMaxMessagesPerRead(int maxMessagesPerRead) {
         super.setMaxMessagesPerRead(maxMessagesPerRead);
         return this;
     }
 
     @Override
     public KQueueChannelConfig setWriteSpinCount(int writeSpinCount) {
         super.setWriteSpinCount(writeSpinCount);
         return this;
     }
 
     @Override
     public KQueueChannelConfig setAllocator(ByteBufAllocator allocator) {
         super.setAllocator(allocator);
         return this;
     }
 
     @Override
     public KQueueChannelConfig setRecvByteBufAllocator(RecvByteBufAllocator allocator) {
         if (!(allocator.newHandle() instanceof RecvByteBufAllocator.ExtendedHandle)) {
             throw new IllegalArgumentException("allocator.newHandle() must return an object of type: " +
                     RecvByteBufAllocator.ExtendedHandle.class);
         }
         super.setRecvByteBufAllocator(allocator);
         return this;
     }
 
     @Override
     public KQueueChannelConfig setAutoRead(boolean autoRead) {
         super.setAutoRead(autoRead);
         return this;
     }
 
     @Override
     @Deprecated
     public KQueueChannelConfig setWriteBufferHighWaterMark(int writeBufferHighWaterMark) {
         super.setWriteBufferHighWaterMark(writeBufferHighWaterMark);
         return this;
     }
 
     @Override
     @Deprecated
     public KQueueChannelConfig setWriteBufferLowWaterMark(int writeBufferLowWaterMark) {
         super.setWriteBufferLowWaterMark(writeBufferLowWaterMark);
         return this;
     }
 
     @Override
     public KQueueChannelConfig setWriteBufferWaterMark(WriteBufferWaterMark writeBufferWaterMark) {
         super.setWriteBufferWaterMark(writeBufferWaterMark);
         return this;
     }
 
     @Override
     public KQueueChannelConfig setMessageSizeEstimator(MessageSizeEstimator estimator) {
         super.setMessageSizeEstimator(estimator);
         return this;
     }
 
     @Override
     protected final void autoReadCleared() {
         ((AbstractKQueueChannel) channel).clearReadFilter();
     }
 
     final void setMaxBytesPerGatheringWrite(long maxBytesPerGatheringWrite) {
         this.maxBytesPerGatheringWrite = min(SSIZE_MAX, maxBytesPerGatheringWrite);
     }
 
     final long getMaxBytesPerGatheringWrite() {
         return maxBytesPerGatheringWrite;
     }
 }