/*
 * Copyright (c) 2010-2012 Sonatype, Inc. All rights reserved.
 *
 * This program is licensed to you under the Apache License Version 2.0,
 * and you may not use this file except in compliance with the Apache License Version 2.0.
 * You may obtain a copy of the Apache License Version 2.0 at http://www.apache.org/licenses/LICENSE-2.0.
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the Apache License Version 2.0 is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the Apache License Version 2.0 for the specific language governing permissions and limitations there under.
 */
package org.asynchttpclient.providers.netty;

import org.asynchttpclient.Body;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.handler.stream.ChunkedInput;

import java.io.IOException;
import java.nio.ByteBuffer;

/**
 * Adapts a {@link Body} to Netty's {@link ChunkedInput}.
 */
class BodyChunkedInput
        implements ChunkedInput {

    private final Body body;

    private final int chunkSize = 1024 * 8;

    private ByteBuffer nextChunk;

    private static final ByteBuffer EOF = ByteBuffer.allocate(0);

    private boolean endOfInput = false;

    public BodyChunkedInput(Body body) {
        if (body == null) {
            throw new IllegalArgumentException("no body specified");
        }
        this.body = body;
    }

    private ByteBuffer peekNextChunk()
            throws IOException {

        if (nextChunk == null) {
            ByteBuffer buffer = ByteBuffer.allocate(chunkSize);
            long length = body.read(buffer);
            if (length < 0) {
                // Negative means this is finished
                buffer.flip();
                nextChunk = buffer;
                endOfInput = true;
            } else if (length == 0) {
                // Zero means we didn't get anything this time, but may get next time
                buffer.flip();
                nextChunk = null;
            } else {
                buffer.flip();
                nextChunk = buffer;
            }
        }
        return nextChunk;
    }

    /**
     * Having no next chunk does not necessarily means end of input, other chunks may arrive later
     */
    public boolean hasNextChunk() throws Exception {
        return peekNextChunk() != null;
    }

    public Object nextChunk() throws Exception {
        ByteBuffer buffer = peekNextChunk();
        if (buffer == null || buffer == EOF) {
            return null;
        }
        nextChunk = null;

        return ChannelBuffers.wrappedBuffer(buffer);
    }

    public boolean isEndOfInput() throws Exception {
        return endOfInput;
    }

    public void close() throws Exception {
        body.close();
    }

}

/*
 * Copyright (c) 2010-2012 Sonatype, Inc. All rights reserved.
 *
 * This program is licensed to you under the Apache License Version 2.0,
 * and you may not use this file except in compliance with the Apache License Version 2.0.
 * You may obtain a copy of the Apache License Version 2.0 at http://www.apache.org/licenses/LICENSE-2.0.
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the Apache License Version 2.0 is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the Apache License Version 2.0 for the specific language governing permissions and limitations there under.
 */
package org.asynchttpclient.providers.netty;

import org.asynchttpclient.Body;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.handler.stream.ChunkedInput;

import java.nio.ByteBuffer;

/**
 * Adapts a {@link Body} to Netty's {@link ChunkedInput}.
 */
class BodyChunkedInput implements ChunkedInput {

    private static final int DEFAULT_CHUNK_SIZE = 8 * 1024;

    private final Body body;
    private final int contentLength;
    private final int chunkSize;

    private boolean endOfInput;

    public BodyChunkedInput(Body body) {
        if (body == null) {
            throw new IllegalArgumentException("no body specified");
        }
        this.body = body;
        contentLength = (int) body.getContentLength();
        if (contentLength <= 0)
            chunkSize = DEFAULT_CHUNK_SIZE;
        else
            chunkSize = Math.min(contentLength, DEFAULT_CHUNK_SIZE);
    }

    public boolean hasNextChunk() throws Exception {
        // unused
        throw new UnsupportedOperationException();
    }

    public Object nextChunk() throws Exception {
        if (endOfInput) {
            return null;
        } else {
            ByteBuffer buffer = ByteBuffer.allocate(chunkSize);
            long r = body.read(buffer);
            if (r < 0L) {
                endOfInput = true;
                return null;
            } else {
                endOfInput = r == contentLength || r < chunkSize && contentLength > 0;
                buffer.flip();
                return ChannelBuffers.wrappedBuffer(buffer);
            }
        }
    }

    public boolean isEndOfInput() throws Exception {
        // called by ChunkedWriteHandler AFTER nextChunk
        return endOfInput;
    }

    public void close() throws Exception {
        body.close();
    }
}

Refactor BodyChunkedInput