/**
 * Copyright (C) 2010-2017 Gordon Fraser, Andrea Arcuri and EvoSuite
 * contributors
 *
 * This file is part of EvoSuite.
 *
 * EvoSuite is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation, either version 3.0 of the License, or
 * (at your option) any later version.
 *
 * EvoSuite 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
 * Lesser Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with EvoSuite. If not, see <http://www.gnu.org/licenses/>.
 */
package org.evosuite.runtime.javaee.javax.persistence;

import org.hibernate.dialect.HSQLDialect;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.persistenceunit.DefaultPersistenceUnitManager;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;

import javax.persistence.*;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.metamodel.Metamodel;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Properties;

/**
 * A wrapper over an actual EntityManagerFactory.
 * Needed to create and control wrapped instances of EntityManager
 *
 * Created by Andrea Arcuri on 16/06/15.
 */
public class EvoEntityManagerFactory implements EntityManagerFactory{

    private final EntityManagerFactory factory;

    private final List<EvoEntityManager> managers;

    public EvoEntityManagerFactory(){
        factory = createEMFWithSpring();
        managers = new ArrayList<>();
    }

    private EntityManagerFactory createEMFWithSpring(){

        DriverManagerDataSource dataSource = new DriverManagerDataSource();

        // DriverManagerDataSource uses the context classloader for some reason...
        ClassLoader cl1 = Thread.currentThread().getContextClassLoader();
        Thread.currentThread().setContextClassLoader(EvoEntityManagerFactory.class.getClassLoader());
        dataSource.setDriverClassName(org.hsqldb.jdbcDriver.class.getName());
        dataSource.setUrl("jdbc:hsqldb:mem:.");
        dataSource.setUsername("sa");
        dataSource.setPassword("");
        Thread.currentThread().setContextClassLoader(cl1);

        LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
        em.setDataSource(dataSource);
        em.setPackagesToScan(""); //search everything on classpath
        em.setJpaVendorAdapter(new HibernateJpaVendorAdapter());


        try {
            /*
                The code in this class works fine on Mac, but somehow it crashes on Debian (Lux cluster).
                So, the following is just a workaround, although not fully understood while on Debian
                it was behaving differently
             */
            Field f = LocalContainerEntityManagerFactoryBean.class.getDeclaredField("internalPersistenceUnitManager");
            f.setAccessible(true);
            DefaultPersistenceUnitManager m = (DefaultPersistenceUnitManager)f.get(em);
            m.setDefaultPersistenceUnitRootLocation(null);
        } catch (Exception e) {
            e.printStackTrace();
        }

        Properties properties = new Properties();
        properties.setProperty("hibernate.show_sql", "true");
        properties.setProperty("hibernate.dialect", HSQLDialect.class.getName());
        properties.setProperty("hibernate.connection.shutdown", "true");
        properties.setProperty("hibernate.hbm2ddl.auto", "create-drop");
        properties.setProperty("hibernate.classloading.use_current_tccl_as_parent", "false");
        em.setJpaProperties(properties);


        em.afterPropertiesSet();

        return em.getObject();
    }

    public void clearAllEntityManagers(){
        for(EvoEntityManager em : managers){
            if(em!=null){
                if (em.isOpen() && !em.isJoinedToTransaction() && em.getTransaction().isActive()) {
                    em.getTransaction().rollback();
                }
                if(em.isOpen()) {
                    em.close();
                }
            }
        }
        managers.clear();
    }

    //----------  EntityManagerFactory ---------------


    @Override
    public EntityManager createEntityManager() {
        EntityManager em = factory.createEntityManager();
        EvoEntityManager evo = new EvoEntityManager(em,this);
        managers.add(evo);

        return evo;
    }

    @Override
    public EntityManager createEntityManager(Map map) {
        EntityManager em = factory.createEntityManager(map);
        EvoEntityManager evo = new EvoEntityManager(em,this);
        managers.add(evo);

        return evo;
    }

    @Override
    public EntityManager createEntityManager(SynchronizationType synchronizationType) {
        EntityManager em = factory.createEntityManager(synchronizationType);
        EvoEntityManager evo = new EvoEntityManager(em,this);
        managers.add(evo);

        return evo;
    }

    @Override
    public EntityManager createEntityManager(SynchronizationType synchronizationType, Map map) {
        EntityManager em = factory.createEntityManager(synchronizationType,map);
        EvoEntityManager evo = new EvoEntityManager(em,this);
        managers.add(evo);

        return evo;
    }

    @Override
    public CriteriaBuilder getCriteriaBuilder() {
        return factory.getCriteriaBuilder();
    }

    @Override
    public Metamodel getMetamodel() {
        return factory.getMetamodel();
    }

    @Override
    public boolean isOpen() {
        return factory.isOpen();
    }

    @Override
    public void close() {
        factory.close();
    }

    @Override
    public Map<String, Object> getProperties() {
        return factory.getProperties();
    }

    @Override
    public Cache getCache() {
        return factory.getCache();
    }

    @Override
    public PersistenceUnitUtil getPersistenceUnitUtil() {
        return factory.getPersistenceUnitUtil();
    }

    @Override
    public void addNamedQuery(String name, Query query) {
        factory.addNamedQuery(name,query);
    }

    @Override
    public <T> T unwrap(Class<T> cls) {
        return factory.unwrap(cls);
    }

    @Override
    public <T> void addNamedEntityGraph(String graphName, EntityGraph<T> entityGraph) {
        factory.addNamedEntityGraph(graphName,entityGraph);
    }
}