// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF 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 streamer;

public class FakeSource extends BaseElement {

  /**
   * Delay for null packets in poll method when blocking is requested, in
   * milliseconds.
   */
  protected long delay = SyncLink.STANDARD_DELAY_FOR_EMPTY_PACKET;

  public FakeSource(String id) {
    super(id);
  }

  @Override
  public void poll(boolean block) {
    if (numBuffers > 0 && packetNumber >= numBuffers) {
      // Close stream when limit of packets is reached
      sendEventToAllPads(Event.STREAM_CLOSE, Direction.OUT);
      return;
    }

    // Prepare new packet
    ByteBuffer buf = initializeData();

    // Push it to output(s)
    pushDataToAllOuts(buf);

    // Make slight delay when blocking input was requested (to avoid
    // consuming of 100% in parent loop)
    if (block)
      delay();

  }

  /**
   * Make slight delay. Should be used when blocking input is requested in pull
   * mode, but null packed was returned by input.
   */
  protected void delay() {
    try {
      Thread.sleep(delay);
    } catch (InterruptedException e) {
    }
  }

  /**
   * Initialize data.
   */
  public ByteBuffer initializeData() {
    ByteBuffer buf = new ByteBuffer(incommingBufLength);

    // Set first byte of package to it sequance number
    buf.data[buf.offset] = (byte) (packetNumber % 128);

    // Initialize rest of bytes with sequential values, which are
    // corresponding with their position in byte buffer
    for (int i = buf.offset + 1; i < buf.length; i++)
      buf.data[i] = (byte) (i % 128);

    buf.putMetadata(ByteBuffer.SEQUENCE_NUMBER, packetNumber);
    buf.putMetadata("src", id);

    return buf;
  }

  @Override
  public String toString() {
    return "FakeSource(" + id + ")";
  }

  public static void main(String args[]) {

    Element fakeSource = new FakeSource("source 3/10/100") {
      {
        verbose = true;
        this.incommingBufLength = 3;
        this.numBuffers = 10;
        this.delay = 100;
      }
    };

    Element fakeSink = new FakeSink("sink") {
      {
        this.verbose = true;
      }
    };

    Element fakeSink2 = new FakeSink("sink2") {
      {
        this.verbose = true;
      }
    };

    Link link = new SyncLink();

    fakeSource.setLink(STDOUT, link, Direction.OUT);
    fakeSink.setLink(STDIN, link, Direction.IN);

    Link link2 = new SyncLink();

    fakeSource.setLink("out2", link2, Direction.OUT);
    fakeSink2.setLink(STDIN, link2, Direction.IN);

    link.run();

  }

}