/*******************************************************************************
 * Copyright (c) 1998, 2009 Oracle. All rights reserved.
 * This program and the accompanying materials are made available under the 
 * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0 
 * which accompanies this distribution. 
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at 
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     dclarke - Dynamic Persistence INCUBATION - Enhancement 200045
 *               http://wiki.eclipse.org/EclipseLink/Development/Dynamic
 *     mnorman - tweaks to work from Ant command-line,
 *               get database properties from System, etc.
 *     
 * This code is being developed under INCUBATION and is not currently included 
 * in the automated EclipseLink build. The API in this code may change, or 
 * may never be included in the product. Please provide feedback through mailing 
 * lists or the bug database.
 ******************************************************************************/
package org.eclipse.persistence.testing.tests.jpa.dynamic;

//javase imports
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.StringReader;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLStreamHandler;
import java.util.Iterator;
import java.util.Map;

import org.xml.sax.InputSource;
import org.xml.sax.XMLReader;

//java eXtension imports
import javax.persistence.EntityManagerFactory;
import javax.persistence.spi.PersistenceProvider;
import javax.persistence.spi.PersistenceUnitInfo;
import javax.persistence.spi.ProviderUtil;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.eclipse.persistence.config.PersistenceUnitProperties;
import org.eclipse.persistence.exceptions.PersistenceUnitLoadingException;
import org.eclipse.persistence.exceptions.XMLParseException;
import org.eclipse.persistence.internal.jpa.EntityManagerFactoryImpl;
import org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl;
import org.eclipse.persistence.internal.jpa.deployment.SEPersistenceUnitInfo;
import org.eclipse.persistence.internal.jpa.deployment.xml.parser.PersistenceContentHandler;
import org.eclipse.persistence.internal.jpa.deployment.xml.parser.XMLException;
import org.eclipse.persistence.internal.jpa.deployment.xml.parser.XMLExceptionHandler;

//domain-specific (testing) imports
import static org.eclipse.persistence.testing.framework.junit.JUnitTestCaseHelper.getDatabaseProperties;

public class DynamicTestHelper {

    public static final String DYNAMIC_PERSISTENCE_NAME = "dynamic";
    static final String DYNAMIC_PERSISTENCE_XML =
        "<?xml version=\"1.0\" encoding=\"UTF-8\"?>" +
        "<persistence version=\"1.0\" xmlns=\"http://java.sun.com/xml/ns/persistence\" " +
            "xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" " +
            "xsi:schemaLocation=\"http://java.sun.com/xml/ns/persistence " +
            "http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd\">" +
            "<persistence-unit name=\"" + DYNAMIC_PERSISTENCE_NAME + 
                "\" transaction-type=\"RESOURCE_LOCAL\">" +
                "<exclude-unlisted-classes>true</exclude-unlisted-classes>" +
            "</persistence-unit>" +
        "</persistence>";

    // custom 'in-memory' URL that doesn't "go" anywhere, doesn't resolve to anything
    static URL dynamicTestUrl = null; 
    static {
        try {
            dynamicTestUrl = new URL(null, "inmemory:", new URLStreamHandler() {
                @Override
                protected URLConnection openConnection(URL url) throws IOException {
                    return new URLConnection(url) {
                        @Override
                        public InputStream getInputStream() throws IOException {
                            return null;
                        }
                        @Override
                        public void connect() throws IOException {
                        }
                    };
                }
            });
        }
        catch (MalformedURLException e) {
            // ignore
        }
    }

    public static EntityManagerFactory createEMF(String emName) {
        PersistenceContentHandler myContentHandler = new PersistenceContentHandler();
        try {
            SAXParserFactory spf = SAXParserFactory.newInstance();
            spf.setNamespaceAware(true);
            SAXParser sp = spf.newSAXParser();
            XMLReader xmlReader = sp.getXMLReader();
            XMLExceptionHandler xmlErrorHandler = new XMLExceptionHandler();
            xmlReader.setErrorHandler(xmlErrorHandler);
            xmlReader.setContentHandler(myContentHandler);
            InputSource inputSource = new InputSource(new StringReader(DYNAMIC_PERSISTENCE_XML));
            xmlReader.parse(inputSource);
        }
        catch (Exception e) {
            return null;
        }
        // only ever one
        final SEPersistenceUnitInfo puInfo = myContentHandler.getPersistenceUnits().get(0);
        puInfo.setPersistenceUnitRootUrl(dynamicTestUrl);
        PersistenceProvider provider = new PersistenceProvider() {
            @Override
            public EntityManagerFactory createContainerEntityManagerFactory(
                PersistenceUnitInfo info, Map map) {
                return null;
            }
            @Override
            public EntityManagerFactory createEntityManagerFactory(String emName, Map map) {
                if (emName.equals(puInfo.getPersistenceUnitName())) {
                    EntityManagerSetupImpl entityManagerSetupImpl = new EntityManagerSetupImpl();
                    map.put(PersistenceUnitProperties.WEAVING, "false");
                    map.put(PersistenceUnitProperties.SESSION_NAME, DYNAMIC_PERSISTENCE_NAME);
                    puInfo.getProperties().put(
                        PersistenceUnitProperties.EXCLUDE_ECLIPSELINK_ORM_FILE, "true");
                    entityManagerSetupImpl.predeploy(puInfo, map);
                    return new EntityManagerFactoryImpl(entityManagerSetupImpl, map);
                }
                else {
                    return null;
                }
            }
            @Override
            public ProviderUtil getProviderUtil() {
                return null;
            }
         };
         return provider.createEntityManagerFactory(emName, getDatabaseProperties());
    }

}