Copyright (c) 2008, 2015 Freescale Semiconductor 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:
    Serge Beauchamp (Freescale Semiconductor) - initial API and implementation
    IBM Corporation - ongoing development
    James Blackburn (Broadcom Corp.) - ongoing development
    Lars Vogel  - Bug 473427
/*******************************************************************************
 * Copyright (c) 2008, 2015 Freescale Semiconductor 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:
 *     Serge Beauchamp (Freescale Semiconductor) - initial API and implementation
 *     IBM Corporation - ongoing development
 *     James Blackburn (Broadcom Corp.) - ongoing development
 *     Lars Vogel <Lars.Vogel@vogella.com> - Bug 473427
 *******************************************************************************/
package org.eclipse.core.internal.resources;

import java.util.HashMap;
import org.eclipse.core.resources.IFilterMatcherDescriptor;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.resources.filtermatchers.AbstractFileInfoMatcher;
import org.eclipse.core.runtime.*;

 This class collects all the registered AbstractFileInfoMatcher instances along with their properties. /**
 *  This class collects all the registered {@link AbstractFileInfoMatcher} instances along
 *  with their properties.
 */
class FilterTypeManager implements IManager {

	private static final String FILTER_ELEMENT = "filterMatcher"; //$NON-NLS-1$

	private HashMap<String, IFilterMatcherDescriptor> factories = new HashMap<>();

	public FilterTypeManager() {
		IExtensionPoint point = RegistryFactory.getRegistry().getExtensionPoint(ResourcesPlugin.PI_RESOURCES, ResourcesPlugin.PT_FILTER_MATCHERS);
		if (point != null) {
			// initial population
			for (IExtension extension : point.getExtensions()) {
				processExtension(extension);
			}
			RegistryFactory.getRegistry().addListener(new IRegistryEventListener() {
				@Override
				public void added(IExtension[] extensions) {
					for (IExtension extension : extensions)
						processExtension(extension);
				}

				@Override
				public void added(IExtensionPoint[] extensionPoints) {
					// nothing to do
				}

				@Override
				public void removed(IExtension[] extensions) {
					for (IExtension extension : extensions)
						processRemovedExtension(extension);
				}

				@Override
				public void removed(IExtensionPoint[] extensionPoints) {
					// nothing to do
				}
			});
		}
	}

	public IFilterMatcherDescriptor getFilterDescriptor(String id) {
		return factories.get(id);
	}

	public IFilterMatcherDescriptor[] getFilterDescriptors() {
		return factories.values().toArray(new IFilterMatcherDescriptor[0]);
	}

	protected void processExtension(IExtension extension) {
		IConfigurationElement[] elements = extension.getConfigurationElements();
		for (IConfigurationElement element : elements) {
			if (element.getName().equalsIgnoreCase(FILTER_ELEMENT)) {
				IFilterMatcherDescriptor desc = new FilterDescriptor(element);
				factories.put(desc.getId(), desc);
			}
		}
	}

	protected void processRemovedExtension(IExtension extension) {
		IConfigurationElement[] elements = extension.getConfigurationElements();
		for (IConfigurationElement element : elements) {
			if (element.getName().equalsIgnoreCase(FILTER_ELEMENT)) {
				IFilterMatcherDescriptor desc = new FilterDescriptor(element, false);
				factories.remove(desc.getId());
			}
		}
	}

	@Override
	public void shutdown(IProgressMonitor monitor) {
		//nothing to do
	}

	@Override
	public void startup(IProgressMonitor monitor) {
		//nothing to do
	}
}