/*******************************************************************************
 * Copyright (c) 2009 Oracle. 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:
 *     Oracle - initial API and implementation
 ******************************************************************************/
package org.eclipse.jpt.jpa.core.internal;

import java.util.Comparator;
import org.eclipse.jpt.jpa.core.JpaFacet;
import org.eclipse.jpt.jpa.core.JpaPlatform;
import org.eclipse.jpt.jpa.core.JpaPlatformFactory;
import org.eclipse.jpt.jpa.core.JpaPlatformVariation;
import org.eclipse.jpt.jpa.core.internal.jpa1.GenericJpaFactory;
import org.eclipse.wst.common.project.facet.core.DefaultVersionComparator;

/**
 * All the state in the JPA platform should be "static" (i.e. unchanging once
 * it is initialized).
 */
public class GenericJpaPlatformFactory
	implements JpaPlatformFactory
{
	/**
	 * zero-argument constructor
	 */
	public GenericJpaPlatformFactory() {
		super();
	}
	
	public JpaPlatform buildJpaPlatform(String id) {
		return new GenericJpaPlatform(
			id,
			this.buildJpaVersion(),
			new GenericJpaFactory(), 
			new GenericJpaAnnotationProvider(GenericJpaAnnotationDefinitionProvider.instance()),
			GenericJpaPlatformProvider.instance(), 
			this.buildJpaPlatformVariation());
	}
	
	
	private JpaPlatform.Version buildJpaVersion() {
		return new SimpleVersion(JpaFacet.VERSION_1_0.getVersionString());
	}
	
	protected JpaPlatformVariation buildJpaPlatformVariation() {
		return new JpaPlatformVariation() {
			public Supported getTablePerConcreteClassInheritanceIsSupported() {
				return Supported.MAYBE;
			}
			public boolean isJoinTableOverridable() {
				return false;
			}
		};
	}


	public static class SimpleVersion implements JpaPlatform.Version {
		protected final String jpaVersion;

		public static final Comparator<String> JPA_VERSION_COMPARATOR = new DefaultVersionComparator();

		public SimpleVersion(String jpaVersion) {
			super();
			this.jpaVersion = jpaVersion;
		}

		/**
		 * The generic platform's version is the same as the JPA version.
		 */
		public String getVersion() {
			return this.getJpaVersion();
		}
		
		public String getJpaVersion() {
			return this.jpaVersion;
		}

		/**
		 * For now, generic platforms are backward-compatible.
		 */
		public boolean isCompatibleWithJpaVersion(String version) {
			return JPA_VERSION_COMPARATOR.compare(this.jpaVersion, version) >= 0;
		}
		
		@Override
		public String toString() {
			return "JPA version: " + this.getJpaVersion(); //$NON-NLS-1$
		}

	}

}