/*
 This file belongs to the Servoy development and deployment environment, Copyright (C) 1997-2012 Servoy BV

 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU Affero General Public License as published by the Free
 Software Foundation; either version 3 of the License, or (at your option) any
 later version.

 This program is distributed in the hope that it will be useful, but WITHOUT
 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more details.

 You should have received a copy of the GNU Affero General Public License along
 with this program; if not, see http://www.gnu.org/licenses or write to the Free
 Software Foundation,Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
 */

package com.servoy.extension;

import java.io.File;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

/**
 * Extension provider that is able to find extensions from multiple sources.
 * For example you might want to combine a local folder extension provider with a Marketplace extension provider. Or you might want to combine two local folders extension providers.
 * @author acostescu
 */
public class ComposedExtensionProvider implements IExtensionProvider
{

	protected final IExtensionProvider provider1;
	protected final IExtensionProvider provider2;

	/**
	 * Creates a new composed extension provider. This will get extension related data from both specified sources.<br>
	 * It will try to find what it needs in provider1 and then in provider2. In case of duplicate entries only one will be returned - the
	 * one from provider1.
	 * @param provider1 the higher priority extension provider.
	 * @param provider2 the lower priority extension provider.
	 */
	public ComposedExtensionProvider(IExtensionProvider provider1, IExtensionProvider provider2)
	{
		this.provider1 = provider1;
		this.provider2 = provider2;
	}

	public DependencyMetadata[] getDependencyMetadata(ExtensionDependencyDeclaration extensionDependency)
	{
		DependencyMetadata[] dmd1 = provider1.getDependencyMetadata(extensionDependency);
		DependencyMetadata[] dmd2 = provider2.getDependencyMetadata(extensionDependency);

		// if there are duplicates (same extension id/version), only return the ones from provider1
		List<DependencyMetadata> result = new ArrayList<DependencyMetadata>((dmd1 != null ? dmd1.length : 0) + (dmd2 != null ? dmd2.length : 0));
		if (dmd1 != null) result.addAll(Arrays.asList(dmd1));
		if (dmd2 != null)
		{
			for (DependencyMetadata dmd : dmd2)
			{
				// check to see that it's not already present from provider1
				boolean found = false;
				for (int i = result.size() - 1; !found && i >= 0; i--)
				{
					if (dmd.id.equals(result.get(i).id) && VersionStringUtils.sameVersion(dmd.version, result.get(i).version))
					{
						found = true;
					}
				}
				if (!found)
				{
					result.add(dmd);
				}
			}
		}

		return result.size() > 0 ? result.toArray(new DependencyMetadata[result.size()]) : null;
	}

	public File getEXPFile(String extensionId, String version, IProgress progress)
	{
		// TODO create separate sub-progress monitors
		File f = provider1.getEXPFile(extensionId, version, progress);
		if (f == null) f = provider2.getEXPFile(extensionId, version, progress);
		return f;
	}

	public Message[] getMessages()
	{
		Message[] w1 = provider1.getMessages();
		Message[] w2 = provider2.getMessages();
		ArrayList<Message> messages = new ArrayList<Message>(w1.length + w2.length);

		messages.addAll(Arrays.asList(w1));
		messages.addAll(Arrays.asList(w2));
		return messages.toArray(new Message[messages.size()]);
	}

	public void clearMessages()
	{
		provider1.clearMessages();
		provider2.clearMessages();
	}

	public void dispose()
	{
		provider1.dispose();
		provider2.dispose();
	}

}