* 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.

*/

* This managers determines when to run a non-root fragment node.

*/

  private final PlanFragment fragment;

  private FragmentRoot root;

  private final IncomingBuffers buffers;

  private final StatusReporter runnerListener;

  private volatile FragmentExecutor runner;

  private volatile boolean cancel = false;

  private final WorkerBee bee;

  private final FragmentContext context;

  private List<RemoteConnection> connections = new CopyOnWriteArrayList<>();

  public NonRootFragmentManager(PlanFragment fragment, WorkerBee bee) throws FragmentSetupException{

    try{

      this.fragment = fragment;

      DrillbitContext context = bee.getContext();

      this.bee = bee;

      this.root = context.getPlanReader().readFragmentOperator(fragment.getFragmentJson());

      this.context = new FragmentContext(context, fragment, null, context.getFunctionImplementationRegistry());

      this.buffers = new IncomingBuffers(root, this.context);

      this.context.setBuffers(buffers);

      this.runnerListener = new NonRootStatusReporter(this.context, context.getController().getTunnel(fragment.getForeman()));

    }catch(ExecutionSetupException | IOException e){

      throw new FragmentSetupException("Failure while decoding fragment.", e);

    }

  }

  /* (non-Javadoc)

   * @see org.apache.drill.exec.work.fragment.FragmentHandler#handle(org.apache.drill.exec.rpc.RemoteConnection.ConnectionThrottle, org.apache.drill.exec.record.RawFragmentBatch)

   */

  @Override

  public boolean handle(RawFragmentBatch batch) throws FragmentSetupException {

    return buffers.batchArrived(batch);

  }

  /* (non-Javadoc)

   * @see org.apache.drill.exec.work.fragment.FragmentHandler#getRunnable()

   */

  @Override

  public FragmentExecutor getRunnable(){

    synchronized(this){

      if(runner != null) throw new IllegalStateException("Get Runnable can only be run once.");

      if(cancel) return null;

      runner = new FragmentExecutor(context, bee, root, runnerListener);

      return this.runner;

    }

  }

  /* (non-Javadoc)

   * @see org.apache.drill.exec.work.fragment.FragmentHandler#cancel()

   */

  @Override

  public void cancel(){

    synchronized(this){

      cancel = true;

      if(runner != null){

        runner.cancel();

      }

    }

  }

  @Override

  public FragmentHandle getHandle() {

    return fragment.getHandle();

  }

  @Override

  public boolean isWaiting() {

    return !buffers.isDone() && !cancel;

  }

  @Override

  public FragmentContext getFragmentContext() {

    return context;

  }

  @Override

  public void addConnection(RemoteConnection connection) {

    connections.add(connection);

  }

  @Override

  public void setAutoRead(boolean autoRead) {

    for (RemoteConnection c : connections) {

      c.setAutoRead(autoRead);

    }

  }

}