/*
 * 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.testsuite.transport.socket;

import io.netty.bootstrap.Bootstrap;
import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.CompositeByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import org.junit.Test;

import java.io.IOException;
import java.util.Random;
import java.util.concurrent.atomic.AtomicReference;

import static org.junit.Assert.*;

public class SocketGatheringWriteTest extends AbstractSocketTest {

    private static final Random random = new Random();
    static final byte[] data = new byte[1048576];

    static {
        random.nextBytes(data);
    }

    @Test(timeout = 30000)
    public void testGatheringWrite() throws Throwable {
        run();
    }

    public void testGatheringWrite(ServerBootstrap sb, Bootstrap cb) throws Throwable {
        testGatheringWrite0(sb, cb, false);
    }

    @Test(timeout = 30000)
    public void testGatheringWriteWithComposite() throws Throwable {
        run();
    }

    public void testGatheringWriteWithComposite(ServerBootstrap sb, Bootstrap cb) throws Throwable {
        testGatheringWrite0(sb, cb, true);
    }

    private static void testGatheringWrite0(ServerBootstrap sb, Bootstrap cb, boolean composite) throws Throwable {
        final TestHandler sh = new TestHandler();
        final TestHandler ch = new TestHandler();

        cb.handler(ch);
        sb.childHandler(sh);

        Channel sc = sb.bind().sync().channel();
        Channel cc = cb.connect().sync().channel();

        for (int i = 0; i < data.length;) {
            int length = Math.min(random.nextInt(1024 * 64), data.length - i);
            ByteBuf buf = Unpooled.wrappedBuffer(data, i, length);
            if (composite && i % 2 == 0) {
                int split =  buf.readableBytes() / 2;
                int size = buf.readableBytes() - split;
                int oldIndex = buf.writerIndex();
                buf.writerIndex(split);
                ByteBuf buf2 = Unpooled.buffer(size).writeBytes(buf, split, oldIndex - split);
                CompositeByteBuf comp = Unpooled.compositeBuffer();
                comp.addComponent(buf).addComponent(buf2).writerIndex(length);
                cc.write(comp);
            } else {
                cc.write(buf);
            }
            i += length;
        }
        assertNotEquals(cc.voidPromise(), cc.writeAndFlush(Unpooled.EMPTY_BUFFER).sync());

        while (sh.counter < data.length) {
            if (sh.exception.get() != null) {
                break;
            }
            if (ch.exception.get() != null) {
                break;
            }
            try {
                Thread.sleep(50);
            } catch (InterruptedException e) {
                // Ignore.
            }
        }
        sh.channel.close().sync();
        ch.channel.close().sync();
        sc.close().sync();

        if (sh.exception.get() != null && !(sh.exception.get() instanceof IOException)) {
            throw sh.exception.get();
        }
        if (sh.exception.get() != null) {
            throw sh.exception.get();
        }
        if (ch.exception.get() != null && !(ch.exception.get() instanceof IOException)) {
            throw ch.exception.get();
        }
        if (ch.exception.get() != null) {
            throw ch.exception.get();
        }
        assertEquals(0, ch.counter);
        assertEquals(Unpooled.wrappedBuffer(data), sh.received);
    }

    private static class TestHandler extends SimpleChannelInboundHandler<ByteBuf> {
        volatile Channel channel;
        final AtomicReference<Throwable> exception = new AtomicReference<Throwable>();
        volatile int counter;
        final ByteBuf received = Unpooled.buffer();
        @Override
        public void channelActive(ChannelHandlerContext ctx)
                throws Exception {
            channel = ctx.channel();
        }

        @Override
        public void channelRead0(ChannelHandlerContext ctx, ByteBuf in) throws Exception {
            counter += in.readableBytes();
            received.writeBytes(in);
        }

        @Override
        public void exceptionCaught(ChannelHandlerContext ctx,
                Throwable cause) throws Exception {
            if (exception.compareAndSet(null, cause)) {
                ctx.close();
            }
        }
    }
}