package org.jboss.as.clustering.infinispan.subsystem;

import static org.jboss.as.controller.ControllerMessages.MESSAGES;
import static org.jboss.as.controller.descriptions.ModelDescriptionConstants.NAME;
import static org.jboss.as.controller.descriptions.ModelDescriptionConstants.VALUE;

import java.util.HashMap;
import java.util.Map;

import org.jboss.as.controller.AttributeDefinition;
import org.jboss.as.controller.OperationContext;
import org.jboss.as.controller.OperationFailedException;
import org.jboss.as.controller.OperationStepHandler;
import org.jboss.as.controller.PathAddress;
import org.jboss.as.controller.operations.validation.ParametersValidator;
import org.jboss.as.controller.registry.ManagementResourceRegistration;
import org.jboss.dmr.ModelNode;

/**
 * Attribute handler for cache resource.
 *
 * @author Richard Achmatowicz (c) 2011 Red Hat Inc.
 */
public class CacheWriteAttributeHandler implements OperationStepHandler {

    public static final CacheWriteAttributeHandler INSTANCE = new CacheWriteAttributeHandler();
    private final ParametersValidator nameValidator = new ParametersValidator();

    private final Map<String, AttributeDefinition> attributeDefinitions;

    public CacheWriteAttributeHandler(final AttributeDefinition... definitions) {
        assert definitions != null : MESSAGES.nullVar("definitions").getLocalizedMessage();
        attributeDefinitions = new HashMap<String, AttributeDefinition>();
        for (AttributeDefinition def : definitions) {
            attributeDefinitions.put(def.getName(), def);
        }
    }

    /**
     * An attribute write handler which performs special processing for ALIAS attributes.
     *
     * @param context the operation context
     * @param operation the operation being executed
     * @throws org.jboss.as.controller.OperationFailedException
     */
    @Override
    public void execute(OperationContext context, ModelNode operation) throws OperationFailedException {

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

        // Don't require VALUE. Let the validator decide if it's bothered by an undefined value
        ModelNode newValue = operation.hasDefined(VALUE) ? operation.get(VALUE) : new ModelNode();
        final ModelNode submodel = context.readResourceForUpdate(PathAddress.EMPTY_ADDRESS).getModel();

        AttributeDefinition attributeDefinition = null;
        attributeDefinition = getAttributeDefinition(attributeName);
        if (attributeDefinition != null) {
            final ModelNode syntheticOp = new ModelNode();
            syntheticOp.get(attributeName).set(newValue);
            attributeDefinition.validateAndSet(syntheticOp, submodel);
        } else {
            submodel.get(attributeName).set(newValue);
        }

        // since we modified the model, set reload required
        if (requiresRuntime(context)) {
            context.addStep(new OperationStepHandler() {
                @Override
                public void execute(OperationContext context, ModelNode operation) throws OperationFailedException {
                    context.reloadRequired();
                    context.completeStep();
                }
            }, OperationContext.Stage.RUNTIME);
        }
        context.completeStep();
    }

     /**
      * Gets whether a {@link org.jboss.as.controller.OperationContext.Stage#RUNTIME} handler should be added. This default implementation
      * returns {@code true} if the {@link org.jboss.as.controller.OperationContext#getProcessType()}  process type} is
      * a server and {@link org.jboss.as.controller.OperationContext#isBooting() context.isBooting()} returns {@code false}.
      *
      * @param context operation context
      * @return {@code true} if a runtime stage handler should be added; {@code false} otherwise.
      */
     protected boolean requiresRuntime(OperationContext context) {
         return context.getProcessType().isServer() && !context.isBooting();
     }

     protected AttributeDefinition getAttributeDefinition(final String attributeName) {
         return attributeDefinitions == null ? null : attributeDefinitions.get(attributeName);
     }

    public void registerAttributes(final ManagementResourceRegistration registry) {
        for (AttributeDefinition attr : attributeDefinitions.values()) {
           registry.registerReadWriteAttribute(attr, CacheReadAttributeHandler.INSTANCE, this);
        }
    }
}
