/*******************************************************************************
 (c) 2005-2014 Copyright, Real-Time Innovations, Inc.  All rights reserved.
 RTI grants Licensee a license to use, modify, compile, and create derivative
 works of the Software.  Licensee has the right to distribute object form only
 for use with RTI products.  The Software is provided "as is", with no warranty
 of any type, including any warranty for fitness for any purpose. RTI is under
 no obligation to maintain or support the Software.  RTI shall not be liable for
 any incidental or consequential damages arising out of the use or inability to
 use the software.
 ******************************************************************************/

import java.util.Objects;

import com.rti.dds.domain.DomainParticipant;
import com.rti.dds.domain.DomainParticipantFactory;
import com.rti.dds.dynamicdata.DynamicData;
import com.rti.dds.dynamicdata.DynamicDataTypeSupport;
import com.rti.dds.dynamicdata.DynamicDataReader;
import com.rti.dds.dynamicdata.DynamicDataSeq;
import com.rti.dds.infrastructure.ConditionSeq;
import com.rti.dds.infrastructure.Duration_t;
import com.rti.dds.infrastructure.RETCODE_NO_DATA;
import com.rti.dds.infrastructure.RETCODE_TIMEOUT;
import com.rti.dds.infrastructure.ResourceLimitsQosPolicy;
import com.rti.dds.infrastructure.StatusKind;
import com.rti.dds.infrastructure.WaitSet;
import com.rti.dds.subscription.InstanceStateKind;
import com.rti.dds.subscription.ReadCondition;
import com.rti.dds.subscription.SampleInfo;
import com.rti.dds.subscription.SampleInfoSeq;
import com.rti.dds.subscription.SampleStateKind;
import com.rti.dds.subscription.Subscriber;
import com.rti.dds.subscription.ViewStateKind;
import com.rti.dds.topic.Topic;
import com.rti.dds.typecode.TypeCode;

// ===========================================================================

public class ShapeTypeSubscriber extends Application implements AutoCloseable {
    private static String EXAMPLE_TYPE_NAME = "ShapesType";

    private DomainParticipant participant = null;  // Usually one per
                                                   // application
    private DynamicDataReader reader = null;
    private final DynamicDataSeq dataSeq = new DynamicDataSeq();
    private final SampleInfoSeq infoSeq = new SampleInfoSeq();

    private int processData()
    {
        int samplesRead = 0;

        try {
            // Take available data from DataReader's queue
            reader.take(
                    dataSeq,
                    infoSeq,
                    ResourceLimitsQosPolicy.LENGTH_UNLIMITED,
                    SampleStateKind.ANY_SAMPLE_STATE,
                    ViewStateKind.ANY_VIEW_STATE,
                    InstanceStateKind.ANY_INSTANCE_STATE);

            for (int i = 0; i < dataSeq.size(); ++i) {
                SampleInfo info = infoSeq.get(i);

                if (info.valid_data) {
                    DynamicData data = (DynamicData) dataSeq.get(i);
                    data.print(null, 1);
                }
                samplesRead++;
            }
        } catch (RETCODE_NO_DATA noData) {
            // No data to process, not a problem
        } finally {
            // Data loaned from Connext for performance. Return loan when done.
            reader.return_loan(dataSeq, infoSeq);
        }

        return samplesRead;
    }

    // -----------------------------------------------------------------------

    private void runApplication()
    {
        // Start communicating in a domain
        participant = Objects.requireNonNull(
                DomainParticipantFactory.get_instance().create_participant(
                        getDomainId(),
                        DomainParticipantFactory.PARTICIPANT_QOS_DEFAULT,
                        null,  // listener
                        StatusKind.STATUS_MASK_NONE));

        // A Subscriber allows an application to create one or more DataReaders
        Subscriber subscriber =
                Objects.requireNonNull(participant.create_subscriber(
                        DomainParticipant.SUBSCRIBER_QOS_DEFAULT,
                        null,  // listener
                        StatusKind.STATUS_MASK_NONE));

        /*
         * Create DynamicData using TypeCode from ShapeTypeTypeCode If you
         * are NOT using a type generated with rtiddsgen, you need to create
         * this TypeCode from scratch.
         */
        TypeCode typeCode = ShapeTypeTypeCode.VALUE;

        // Create the Dynamic data type support object
        DynamicDataTypeSupport typeSupport = new DynamicDataTypeSupport(
                typeCode,
                DynamicDataTypeSupport.TYPE_PROPERTY_DEFAULT);

        // Register type before creating topic
        String typeName = EXAMPLE_TYPE_NAME;
        typeSupport.register_type(participant, typeName);

        /*
         * Make sure both publisher and subscriber share the same topic
         * name. In the Shapes example: we are subscribing to a Square, wich
         * is the topic name. If you want to publish other shapes (Triangle
         * or Circle), you just need to update the topic name.
         */
        Topic topic = Objects.requireNonNull(participant.create_topic(
                "Square",
                typeName,
                DomainParticipant.TOPIC_QOS_DEFAULT,
                null,  // listener
                StatusKind.STATUS_MASK_NONE));

        // This DataReader reads data on "Square" Topic
        reader = (DynamicDataReader) Objects.requireNonNull(
                subscriber.create_datareader(
                        topic,
                        Subscriber.DATAREADER_QOS_DEFAULT,
                        null,  // listener
                        StatusKind.STATUS_MASK_NONE));

        // Create ReadCondition that triggers when data in reader's queue
        ReadCondition condition = reader.create_readcondition(
                SampleStateKind.ANY_SAMPLE_STATE,
                ViewStateKind.ANY_VIEW_STATE,
                InstanceStateKind.ANY_INSTANCE_STATE);

        // WaitSet will be woken when the attached condition is triggered, or
        // timeout
        WaitSet waitset = new WaitSet();
        waitset.attach_condition(condition);
        final Duration_t waitTimeout = new Duration_t(1, 0);

        int samplesRead = 0;
        ConditionSeq activeConditions = new ConditionSeq();

        // Main loop. Wait for data to arrive and process when it arrives
        while (!isShutdownRequested() && samplesRead < getMaxSampleCount()) {
            try {
                // Wait fills in activeConditions or times out
                waitset.wait(activeConditions, waitTimeout);

                // Read condition triggered, process data
                samplesRead += processData();

            } catch (RETCODE_TIMEOUT timeout) {
                // No data received, not a problem
            }
        }
    }

    @Override public void close()
    {
        // Delete all entities (DataReader, Topic, Subscriber,
        // DomainParticipant)
        if (participant != null) {
            participant.delete_contained_entities();

            DomainParticipantFactory.get_instance().delete_participant(
                    participant);
        }
    }

    public static void main(String[] args)
    {
        // Create example and run: Uses try-with-resources,
        // subscriberApplication.close() automatically called
        try (ShapeTypeSubscriber subscriberApplication =
                     new ShapeTypeSubscriber()) {
            subscriberApplication.parseArguments(args);
            subscriberApplication.addShutdownHook();
            subscriberApplication.runApplication();
        }

        // Releases the memory used by the participant factory. Optional at
        // application exit.
        DomainParticipantFactory.finalize_instance();
    }
}