Copyright (c) 2005, 2018 IBM Corporation 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:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2005, 2018 IBM Corporation 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/

package org.eclipse.equinox.internal.app;

import java.net.URL;
import java.security.AccessController;
import java.util.*;
import org.eclipse.equinox.app.IApplicationContext;
import org.osgi.framework.Bundle;
import org.osgi.framework.ServiceRegistration;
import org.osgi.service.application.*;
import org.osgi.service.condpermadmin.BundleSignerCondition;
import org.osgi.service.condpermadmin.ConditionInfo;

/*
 * An ApplicationDescriptor for an eclipse application.
 */
public class EclipseAppDescriptor extends ApplicationDescriptor {
	static final String APP_TYPE = "eclipse.application.type"; //$NON-NLS-1$
	static final String APP_DEFAULT = "eclipse.application.default"; //$NON-NLS-1$
	static final String APP_TYPE_MAIN_THREAD = "main.thread"; //$NON-NLS-1$
	static final String APP_TYPE_ANY_THREAD = "any.thread"; //$NON-NLS-1$
	static final int FLAG_VISIBLE = 0x01;
	static final int FLAG_CARD_SINGLETON_GLOGAL = 0x02;
	static final int FLAG_CARD_SINGLETON_SCOPED = 0x04;
	static final int FLAG_CARD_UNLIMITED = 0x08;
	static final int FLAG_CARD_LIMITED = 0x10;
	static final int FLAG_TYPE_MAIN_THREAD = 0x20;
	static final int FLAG_TYPE_ANY_THREAD = 0x40;
	static final int FLAG_DEFAULT_APP = 0x80;
	private long instanceID = 0;
	private ServiceRegistration sr;
	private Boolean locked = Boolean.FALSE;
	private final EclipseAppContainer appContainer;
	private final Bundle contributor;
	private final int flags;
	private final int cardinality;
	private final String name;
	private final URL iconURL;
	private final boolean[] registrationLock = new boolean[] {true};

	protected EclipseAppDescriptor(Bundle contributor, String pid, String name, String iconPath, int flags, int cardinality, EclipseAppContainer appContainer) {
		super(pid);
		this.name = name;
		this.contributor = contributor;
		this.appContainer = appContainer;
		this.locked = AppPersistence.isLocked(this) ? Boolean.TRUE : Boolean.FALSE;
		this.flags = flags;
		this.cardinality = cardinality;
		URL iconResult = null;
		// this bit of code is complex because we want to search fragments;
		// that can only be done by using the Bundle.findEntries method which
		// requires the path to be split up between the base and the file name!!
		if (iconPath != null && iconPath.length() > 0) {
			if (iconPath.charAt(0) == '/')
				iconPath = iconPath.substring(1);
			String baseIconDir = "/"; //$NON-NLS-1$
			String iconFile = iconPath;
			int lastSlash = iconPath.lastIndexOf('/');
			if (lastSlash > 0 && lastSlash < iconPath.length() - 1) {
				baseIconDir = iconPath.substring(0, lastSlash);
				iconFile = iconPath.substring(lastSlash + 1);
			}
			Enumeration<URL> urls = contributor.findEntries(baseIconDir, iconFile, false);
			if (urls != null && urls.hasMoreElements())
				iconResult = urls.nextElement();
		}
		this.iconURL = iconResult;
	}

	@Override
	protected Map getPropertiesSpecific(String locale) {
		// just use the service properties; for now we do not localize any properties
		return getServiceProperties();
	}

	@Override
	protected ApplicationHandle launchSpecific(Map arguments) throws Exception {
		// if this application is locked throw an exception.
		if (getLocked().booleanValue())
			throw new IllegalStateException("Cannot launch a locked application."); //$NON-NLS-1$
		// initialize the appHandle
		EclipseAppHandle appHandle = createAppHandle(arguments);
		try {
			// use the appContainer to launch the application on the main thread.
			appContainer.launch(appHandle);
		} catch (Throwable t) {
			// be sure to destroy the appHandle if an error occurs
			try {
				appHandle.destroy();
			} catch (Throwable destroyError) {
				// ignore and clean up
			}
			if (t instanceof Exception)
				throw (Exception) t;
			throw (Error) t;
		}
		return appHandle;
	}

	@Override
	protected synchronized void lockSpecific() {
		locked = Boolean.TRUE;
		// make sure the service properties are updated with the latest lock info
		refreshProperties();
	}

	@Override
	protected synchronized void unlockSpecific() {
		locked = Boolean.FALSE;
		// make sure the service properties are updated with the latest lock info
		refreshProperties();
	}

	void refreshProperties() {
		ServiceRegistration reg = getServiceRegistration();
		if (reg != null)
			try {
				reg.setProperties(getServiceProperties());
			} catch (IllegalStateException e) {
				// this must mean the service was unregistered
				// just ignore
			}
	}

	void setServiceRegistration(ServiceRegistration sr) {
		synchronized (registrationLock) {
			this.sr = sr;
			registrationLock[0] = sr != null;
			registrationLock.notifyAll();
		}

	}

	private ServiceRegistration getServiceRegistration() {
		synchronized (registrationLock) {
			if (sr == null && registrationLock[0])
				try {
					registrationLock.wait(1000); // timeout after 1 second
				} catch (InterruptedException e) {
					// nothing
				}
			return sr;
		}
	}

	private synchronized Boolean getLocked() {
		return locked;
	}

	/*
	 * Gets a snapshot of the current service properties.
	 */
	Hashtable<String, Object> getServiceProperties() {
		Hashtable<String, Object> props = new Hashtable<>(10);
		props.put(ApplicationDescriptor.APPLICATION_PID, getApplicationId());
		if (name != null)
			props.put(ApplicationDescriptor.APPLICATION_NAME, name);
		props.put(ApplicationDescriptor.APPLICATION_CONTAINER, Activator.PI_APP);
		props.put(ApplicationDescriptor.APPLICATION_LOCATION, getLocation());
		Boolean launchable = appContainer.isLocked(this) == 0 ? Boolean.TRUE : Boolean.FALSE;
		props.put(ApplicationDescriptor.APPLICATION_LAUNCHABLE, launchable);
		props.put(ApplicationDescriptor.APPLICATION_LOCKED, getLocked());
		Boolean visible = (flags & FLAG_VISIBLE) != 0 ? Boolean.TRUE : Boolean.FALSE;
		props.put(ApplicationDescriptor.APPLICATION_VISIBLE, visible);
		props.put(APP_TYPE, getThreadTypeString());
		if ((flags & FLAG_DEFAULT_APP) != 0)
			props.put(APP_DEFAULT, Boolean.TRUE);
		if (iconURL != null)
			props.put(ApplicationDescriptor.APPLICATION_ICON, iconURL);
		return props;
	}

	private String getLocation() {
		if (contributor == null)
			return ""; //$NON-NLS-1$
		return Activator.getLocation(contributor);
	}

	/*
	 * Returns the appHandle.  If it does not exist then one is created.
	 */
	private EclipseAppHandle createAppHandle(Map<String, Object> arguments) throws ApplicationException {
		EclipseAppHandle newAppHandle = new EclipseAppHandle(getInstanceID(), arguments, this);
		appContainer.lock(newAppHandle);
		ServiceRegistration appHandleReg = (ServiceRegistration) AccessController.doPrivileged(appContainer.getRegServiceAction(new String[] {ApplicationHandle.class.getName(), IApplicationContext.class.getName()}, newAppHandle, newAppHandle.getServiceProperties()));
		newAppHandle.setServiceRegistration(appHandleReg);
		return newAppHandle;
	}

	EclipseAppContainer getContainerManager() {
		return appContainer;
	}

	@Override
	public boolean matchDNChain(String pattern) {
		if (contributor == null)
			return false;
		return BundleSignerCondition.getCondition(contributor, new ConditionInfo(BundleSignerCondition.class.getName(), new String[] {pattern})).isSatisfied();
	}

	@Override
	protected boolean isLaunchableSpecific() {
		return true;
	}

	public void unregister() {
		ServiceRegistration temp = getServiceRegistration();
		if (temp != null) {
			setServiceRegistration(null);
			temp.unregister();
		}
	}

	String getThreadTypeString() {
		if ((flags & FLAG_TYPE_ANY_THREAD) != 0)
			return APP_TYPE_ANY_THREAD;
		return APP_TYPE_MAIN_THREAD;
	}

	int getThreadType() {
		return flags & (FLAG_TYPE_ANY_THREAD | FLAG_TYPE_MAIN_THREAD);
	}

	int getCardinalityType() {
		return flags & (FLAG_CARD_SINGLETON_GLOGAL | FLAG_CARD_SINGLETON_SCOPED | FLAG_CARD_LIMITED | FLAG_CARD_UNLIMITED);
	}

	int getCardinality() {
		return cardinality;
	}

	private synchronized String getInstanceID() {
		// make sure the instanceID has not reached the max
		if (instanceID == Long.MAX_VALUE)
			instanceID = 0;
		// create a unique instance id
		return getApplicationId() + "." + instanceID++; //$NON-NLS-1$
	}
}