/*******************************************************************************
 * Copyright (c) 2004, 2012 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.wst.css.core.internal.metamodel;

import java.text.Collator;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.eclipse.core.runtime.Platform;
import org.eclipse.wst.css.core.internal.IProductConstants;
import org.eclipse.wst.css.core.internal.metamodelimpl.RegistryReader;

public class CSSProfileRegistry {

	CSSProfile fDefault = null;

	public synchronized static CSSProfileRegistry getInstance() {
		if (fInstance == null) {
			fInstance = new CSSProfileRegistry();
		}
		return fInstance;
	}
	
	static class ProfileNameComparator implements Comparator {
		static Collator delegate = Collator.getInstance();

		public int compare(Object o1, Object o2) {
			if (o1 instanceof CSSProfile && o2 instanceof CSSProfile) {
				if (((CSSProfile) o1).getProfileName() != null && ((CSSProfile) o2).getProfileName() != null) {
					return delegate.compare(((CSSProfile) o1).getProfileName(), ((CSSProfile) o2).getProfileName());
				}
			}
			return 0;
		}
	}

	public Iterator getProfiles() {
		List values = new ArrayList(fProfiles.values());
		Collections.sort(values, new ProfileNameComparator());
		return Collections.unmodifiableCollection(values).iterator();
	}

	public CSSProfile getProfile(String profileID) {
		return (CSSProfile) fProfiles.get(profileID);
	}

	public CSSProfile getDefaultProfile() {
		if (fDefault != null) {
			return fDefault;
		}

		String id = Platform.getProduct() != null ? Platform.getProduct().getProperty(IProductConstants.DEFAULT_PROFILE) : null;

		Iterator i = getProfiles();
		CSSProfile firstDefault = null;
		while (i.hasNext()) {
			CSSProfile profile = (CSSProfile) i.next();
			if (profile.isDefault()) {
				if (id == null) { // Original scenario
					fDefault = profile;
					return profile;
				}
				else if (firstDefault == null) { // extension point used, flag the first default in case the id doesn't end up matching
					firstDefault = profile;
				}
			}
			if (id != null && id.equals(profile.getProfileID())) { // Found the profile for the extension
				fDefault = profile;
				return profile;
			}
		}
		return firstDefault;
	}

	/**
	 * Constructor for CSSProfileRegistry.
	 */
	private CSSProfileRegistry() {
		super();
		fProfiles = new HashMap();
		Iterator i = new RegistryReader().enumProfiles();
		while (i.hasNext()) {
			Object profile = i.next();
			if (profile instanceof CSSProfile) {
				fProfiles.put(((CSSProfile) profile).getProfileID(), profile);
			}
		}
	}


	private static CSSProfileRegistry fInstance = null;
	private Map fProfiles = null;
}