/*
 * Copyright (c) 2008, 2020 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package org.glassfish.grizzly.nio.transport;

import java.io.IOException;
import java.net.SocketAddress;

import org.glassfish.grizzly.Buffer;
import org.glassfish.grizzly.CompletionHandler;
import org.glassfish.grizzly.Connection;
import org.glassfish.grizzly.IOEvent;
import org.glassfish.grizzly.Interceptor;
import org.glassfish.grizzly.ReadResult;
import org.glassfish.grizzly.asyncqueue.AsyncQueueReader;
import org.glassfish.grizzly.asyncqueue.AsyncReadQueueRecord;
import org.glassfish.grizzly.nio.AbstractNIOAsyncQueueReader;
import org.glassfish.grizzly.nio.NIOConnection;
import org.glassfish.grizzly.nio.NIOTransport;

The TCP transport AsyncQueueReader implementation, based on the Java NIO 
Author:
Alexey Stashok/**
 * The TCP transport {@link AsyncQueueReader} implementation, based on the Java NIO
 *
 * @author Alexey Stashok
 */
public final class TCPNIOAsyncQueueReader extends AbstractNIOAsyncQueueReader {
    public TCPNIOAsyncQueueReader(NIOTransport transport) {
        super(transport);
    }

    @Override
    protected int read0(final Connection connection, Buffer buffer, final ReadResult<Buffer, SocketAddress> currentResult) throws IOException {

        final int oldPosition = buffer != null ? buffer.position() : 0;
        if ((buffer = ((TCPNIOTransport) transport).read(connection, buffer)) != null) {
            final int readBytes = buffer.position() - oldPosition;
            currentResult.setMessage(buffer);
            currentResult.setReadSize(currentResult.getReadSize() + readBytes);
            currentResult.setSrcAddressHolder(((TCPNIOConnection) connection).peerSocketAddressHolder);

            return readBytes;
        }

        return 0;
    }

    protected void addRecord(Connection connection, Buffer buffer, CompletionHandler completionHandler, Interceptor<ReadResult> interceptor) {
        final AsyncReadQueueRecord record = AsyncReadQueueRecord.create(connection, buffer, completionHandler, interceptor);
        ((TCPNIOConnection) connection).getAsyncReadQueue().offer(record);
    }

    @Override
    protected void onReadyToRead(Connection connection) throws IOException {
        final NIOConnection nioConnection = (NIOConnection) connection;
        nioConnection.enableIOEvent(IOEvent.READ);
    }
}