plugins/org.apache.karaf.eik.core/src/main/java/org/apache/karaf/eik/core/KarafPlatformModelRegistry.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.karaf.eik.core;

import org.apache.karaf.eik.core.internal.KarafCorePluginActivator;

import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExtension;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.Path;
import org.eclipse.core.runtime.Platform;
import org.eclipse.pde.core.plugin.IPluginModelBase;
import org.eclipse.pde.core.plugin.PluginRegistry;

public final class KarafPlatformModelRegistry {

    private static final String ATT_CLASS = "class";

    private static final String TAG_PLATFORM_MODEL_ITEMTYPE = "model";

    private static final String ATT_SYMBOLIC_NAME = "symbolicName";

    private static final String TAG_TRIGGER_BUNDLE_ITEMTYPE = "triggerBundle";

    /**
     *
     * @return
     * @throws CoreException
     */
    public static KarafPlatformModel findActivePlatformModel() throws CoreException {
        final Map<String, IConfigurationElement> triggerBundleMap =
            getTriggerBundlePlatformFactoryMap();

        for (Map.Entry<String, IConfigurationElement> e : triggerBundleMap.entrySet()) {
            final String symbolicName = e.getKey();

            IPluginModelBase karafPlatformPlugin = PluginRegistry.findModel(symbolicName);

            if (karafPlatformPlugin == null) {
                continue;
            }

            final IConfigurationElement c = e.getValue();
            final KarafPlatformModelFactory f =
                (KarafPlatformModelFactory)c.createExecutableExtension(ATT_CLASS);

            final KarafPlatformValidator validator = f.getPlatformValidator();

            IPath modelPath = new Path(karafPlatformPlugin.getInstallLocation()).removeLastSegments(1);
            while(!modelPath.isEmpty() && !modelPath.isRoot()) {
                modelPath = modelPath.removeLastSegments(1);

                if (validator.isValid(modelPath)) {
                    return f.getPlatformModel(modelPath);
                }
            }
        }

        return null;
    }

    /**
     *
     * @param path
     * @return
     * @throws CoreException
     */
    public static KarafPlatformModel findPlatformModel(IPath path) throws CoreException {
        final KarafPlatformModelFactory factory = findPlatformModelFactory(path);

        if (factory == null) {
            return null;
        }

        return factory.getPlatformModel(path);
    }

    /**
     *
     * @param path
     * @return
     */
    public static KarafPlatformModelFactory findPlatformModelFactory(IPath path) throws CoreException {
        final List<KarafPlatformModelFactory> factories = getPlatformModelFactories();

        for (KarafPlatformModelFactory f : factories) {
            if (f.getPlatformValidator().isValid(path)) {
                return f;
            }
        }

        return null;
    }

    /**
     * Gets all {@link KarafPlatformModelFactory} objects that are a "model"
     *
     * @return a {@link List<KarafPlatformModelFactory>} of 0 or more {@code
     *         KarafPlatformModelFactory}
     * @throws CoreException
     *             if there is a problem fetching information from the extension
     *             registry
     */
    public static List<KarafPlatformModelFactory> getPlatformModelFactories() throws CoreException {
        final List<KarafPlatformModelFactory> factories =
            new ArrayList<KarafPlatformModelFactory>();

        final IExtension[] extensions = Platform.getExtensionRegistry()
                                    .getExtensionPoint(KarafCorePluginActivator.PLUGIN_ID, "platformModel")
                                    .getExtensions();

        for (IExtension e : extensions) {
            for (IConfigurationElement c : e.getConfigurationElements()) {

                if (!c.getName().equals(TAG_PLATFORM_MODEL_ITEMTYPE)) {
                    continue;
                }

                KarafPlatformModelFactory f =
                    (KarafPlatformModelFactory)c.createExecutableExtension(ATT_CLASS);



                factories.add(f);
            }
        }

        return factories;
    }

    /**
     *
     * @return
     * @throws CoreException
     */
    public static List<String> getTriggerBundles() throws CoreException {
        final List<String> triggerBundles = new ArrayList<String>();

        triggerBundles.addAll(getTriggerBundlePlatformFactoryMap().keySet());

        return triggerBundles;
    }

    /**
     *
     * @return
     * @throws CoreException
     */
    public static Map<String, IConfigurationElement> getTriggerBundlePlatformFactoryMap() throws CoreException {
        final Map<String, IConfigurationElement> triggerBundleMap =
            new LinkedHashMap<String, IConfigurationElement>();

        final IExtension[] extensions =
            Platform.getExtensionRegistry()
                .getExtensionPoint(KarafCorePluginActivator.PLUGIN_ID, "platformModel")
                .getExtensions();

        for (IExtension e : extensions) {
            for (IConfigurationElement c : e.getConfigurationElements()) {

                if (!c.getName().equals(TAG_PLATFORM_MODEL_ITEMTYPE)) {
                    continue;
                }

                IConfigurationElement[] children = c.getChildren(TAG_TRIGGER_BUNDLE_ITEMTYPE);
                for (IConfigurationElement tb : children) {
                    triggerBundleMap.put(tb.getAttribute(ATT_SYMBOLIC_NAME), c);
                }

            }
        }

        return triggerBundleMap;
    }

}