/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2011, Red Hat, Inc., and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */

package org.jboss.as.messaging;

import static org.jboss.as.messaging.CommonAttributes.CONSUMER_COUNT;
import static org.jboss.as.messaging.CommonAttributes.DELIVERING_COUNT;
import static org.jboss.as.messaging.CommonAttributes.DURABLE;
import static org.jboss.as.messaging.CommonAttributes.FILTER;
import static org.jboss.as.messaging.CommonAttributes.MESSAGES_ADDED;
import static org.jboss.as.messaging.CommonAttributes.MESSAGE_COUNT;
import static org.jboss.as.messaging.CommonAttributes.PAUSED;
import static org.jboss.as.messaging.CommonAttributes.SCHEDULED_COUNT;
import static org.jboss.as.messaging.CommonAttributes.TEMPORARY;
import static org.jboss.as.messaging.HornetQActivationService.ignoreOperationIfServerNotActive;
import static org.jboss.as.messaging.MessagingMessages.MESSAGES;
import static org.jboss.as.messaging.QueueDefinition.ADDRESS;
import static org.jboss.as.messaging.QueueDefinition.DEAD_LETTER_ADDRESS;
import static org.jboss.as.messaging.QueueDefinition.EXPIRY_ADDRESS;
import static org.jboss.as.messaging.QueueDefinition.ID;
import static org.jboss.as.messaging.QueueDefinition.forwardToRuntimeQueue;

import java.util.ArrayList;
import java.util.List;

import org.hornetq.api.core.management.QueueControl;
import org.hornetq.api.core.management.ResourceNames;
import org.hornetq.core.server.HornetQServer;
import org.jboss.as.controller.AbstractRuntimeOnlyHandler;
import org.jboss.as.controller.OperationContext;
import org.jboss.as.controller.OperationFailedException;
import org.jboss.as.controller.PathAddress;
import org.jboss.as.controller.SimpleAttributeDefinition;
import org.jboss.as.controller.descriptions.ModelDescriptionConstants;
import org.jboss.as.controller.operations.validation.ParametersValidator;
import org.jboss.as.controller.operations.validation.StringLengthValidator;
import org.jboss.dmr.ModelNode;
import org.jboss.msc.service.ServiceController;
import org.jboss.msc.service.ServiceName;

/**
 * Implements the {@code read-attribute} operation for runtime attributes exposed by a HornetQ
 * {@link org.hornetq.api.core.management.QueueControl}.
 *
 * @author Brian Stansberry (c) 2011 Red Hat Inc.
 */
public class QueueReadAttributeHandler extends AbstractRuntimeOnlyHandler {

    public static final QueueReadAttributeHandler INSTANCE = new QueueReadAttributeHandler(false);

    public static final QueueReadAttributeHandler RUNTIME_INSTANCE = new QueueReadAttributeHandler(true);

    private ParametersValidator validator = new ParametersValidator();

    private final boolean readStorageAttributes;

    private QueueReadAttributeHandler(final boolean readStorageAttributes) {
        this.readStorageAttributes = readStorageAttributes;
        validator.registerValidator(CommonAttributes.NAME, new StringLengthValidator(1));
    }

    @Override
    protected boolean resourceMustExist(OperationContext context, ModelNode operation) {
        return false;
    }

    @Override
    public void executeRuntimeStep(OperationContext context, ModelNode operation) throws OperationFailedException {
        if(ignoreOperationIfServerNotActive(context, operation)) {
            return;
        }

        validator.validate(operation);
        final String attributeName = operation.require(ModelDescriptionConstants.NAME).asString();

        PathAddress address = PathAddress.pathAddress(operation.require(ModelDescriptionConstants.OP_ADDR));
        String queueName = address.getLastElement().getValue();

        if (forwardToRuntimeQueue(context, operation, RUNTIME_INSTANCE)) {
            context.stepCompleted();
            return;
        }

        final ServiceName hqServiceName = MessagingServices.getHornetQServiceName(address);
        ServiceController<?> hqService = context.getServiceRegistry(false).getService(hqServiceName);
        HornetQServer hqServer = HornetQServer.class.cast(hqService.getValue());
        QueueControl control = QueueControl.class.cast(hqServer.getManagementService().getResource(ResourceNames.CORE_QUEUE + queueName));

        if (MESSAGE_COUNT.getName().equals(attributeName)) {
            context.getResult().set(control.getMessageCount());
        } else if (SCHEDULED_COUNT.getName().equals(attributeName)) {
            context.getResult().set(control.getScheduledCount());
        } else if (CONSUMER_COUNT.getName().equals(attributeName)) {
            context.getResult().set(control.getConsumerCount());
        } else if (DELIVERING_COUNT.getName().equals(attributeName)) {
            context.getResult().set(control.getDeliveringCount());
        } else if (MESSAGES_ADDED.getName().equals(attributeName)) {
            context.getResult().set(control.getMessagesAdded());
        } else if (ID.getName().equals(attributeName)) {
            context.getResult().set(control.getID());
        } else if (PAUSED.getName().equals(attributeName)) {
            try {
                context.getResult().set(control.isPaused());
            } catch (RuntimeException e) {
                throw e;
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        } else if (TEMPORARY.getName().equals(attributeName)) {
            context.getResult().set(control.isTemporary());
        } else if (EXPIRY_ADDRESS.getName().equals(attributeName)) {
            context.getResult().set(control.getExpiryAddress());
        } else if (DEAD_LETTER_ADDRESS.getName().equals(attributeName)) {
            context.getResult().set(control.getDeadLetterAddress());
        } else if (readStorageAttributes && getStorageAttributeNames().contains(attributeName)) {
            if (ADDRESS.getName().equals(attributeName)) {
                context.getResult().set(control.getAddress());
            } else if (DURABLE.getName().equals(attributeName)) {
                context.getResult().set(control.isDurable());
            } else if (FILTER.getName().equals(attributeName)) {
                ModelNode result = context.getResult();
                String filter = control.getFilter();
                if (filter != null) {
                    result.set(filter);
                }
            }
        } else {
            throw MESSAGES.unsupportedAttribute(attributeName);
        }

        context.stepCompleted();
    }

    private static List<String> getStorageAttributeNames() {
        List<String> names = new ArrayList<String>();
        for (SimpleAttributeDefinition attr : QueueDefinition.ATTRIBUTES) {
          names.add(attr.getName());
        }
        return names;
    }
}
