/*******************************************************************************
 * Copyright (c) 2014 Raymond Augé and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     Raymond Augé <raymond.auge@liferay.com> - Bug 436698
 ******************************************************************************/

package org.eclipse.equinox.http.servlet.internal.customizer;

import java.util.concurrent.atomic.AtomicReference;
import org.eclipse.equinox.http.servlet.internal.HttpServiceRuntimeImpl;
import org.eclipse.equinox.http.servlet.internal.context.ContextController;
import org.eclipse.equinox.http.servlet.internal.error.HttpWhiteboardFailureException;
import org.eclipse.equinox.http.servlet.internal.registration.ResourceRegistration;
import org.eclipse.equinox.http.servlet.internal.util.StringPlus;
import org.osgi.framework.*;
import org.osgi.service.http.runtime.dto.DTOConstants;
import org.osgi.service.http.runtime.dto.FailedResourceDTO;
import org.osgi.service.http.whiteboard.HttpWhiteboardConstants;

/**
 * @author Raymond Augé
 */
public class ContextResourceTrackerCustomizer
	extends RegistrationServiceTrackerCustomizer<Object, AtomicReference<ResourceRegistration>> {

	public ContextResourceTrackerCustomizer(
		BundleContext bundleContext, HttpServiceRuntimeImpl httpServiceRuntime,
		ContextController contextController) {

		super(bundleContext, httpServiceRuntime);

		this.contextController = contextController;
	}

	@Override
	public AtomicReference<ResourceRegistration> addingService(
		ServiceReference<Object> serviceReference) {
		AtomicReference<ResourceRegistration> result = new AtomicReference<ResourceRegistration>();
		if (!httpServiceRuntime.matches(serviceReference)) {
			return result;
		}

		if (!contextController.matches(serviceReference)) {
			return result;
		}

		try {
			result.set(contextController.addResourceRegistration(serviceReference));
		}
		catch (HttpWhiteboardFailureException hwfe) {
			httpServiceRuntime.log(hwfe.getMessage(), hwfe);

			recordFailedResourceDTO(serviceReference, hwfe.getFailureReason());
		}
		catch (Throwable t) {
			httpServiceRuntime.log(t.getMessage(), t);

			recordFailedResourceDTO(serviceReference, DTOConstants.FAILURE_REASON_EXCEPTION_ON_INIT);
		}

		return result;
	}

	@Override
	public void modifiedService(
		ServiceReference<Object> serviceReference,
		AtomicReference<ResourceRegistration> resourceReference) {

		removedService(serviceReference, resourceReference);
		AtomicReference<ResourceRegistration> added = addingService(serviceReference);
		resourceReference.set(added.get());
	}

	@Override
	public void removedService(
		ServiceReference<Object> serviceReference,
		AtomicReference<ResourceRegistration> resourceReference) {
		ResourceRegistration registration = resourceReference.get();
		if (registration != null) {
			// destroy will unget the service object we were using
			registration.destroy();
		}

		contextController.getHttpServiceRuntime().removeFailedResourceDTO(serviceReference);
	}

	private void recordFailedResourceDTO(
		ServiceReference<Object> serviceReference, int failureReason) {

		FailedResourceDTO failedResourceDTO = new FailedResourceDTO();

		failedResourceDTO.failureReason = failureReason;
		failedResourceDTO.patterns = StringPlus.from(
			serviceReference.getProperty(HttpWhiteboardConstants.HTTP_WHITEBOARD_RESOURCE_PATTERN)).toArray(new String[0]);
		failedResourceDTO.prefix = (String)serviceReference.getProperty(HttpWhiteboardConstants.HTTP_WHITEBOARD_RESOURCE_PREFIX);
		failedResourceDTO.serviceId = (Long)serviceReference.getProperty(Constants.SERVICE_ID);
		failedResourceDTO.servletContextId = contextController.getServiceId();

		contextController.getHttpServiceRuntime().recordFailedResourceDTO(serviceReference, failedResourceDTO);
	}

	private ContextController contextController;

}