package br.com.germantech.ecf.infraestrutura.persistencia.entityManager;

import java.util.HashMap;
import java.util.Map;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;

import org.apache.log4j.Logger;
import org.eclipse.persistence.config.PersistenceUnitProperties;
import org.eclipse.persistence.config.TargetDatabase;
import org.eclipse.persistence.internal.jpa.EntityManagerImpl;
import org.eclipse.persistence.jpa.PersistenceProvider;
import org.eclipse.persistence.sessions.UnitOfWork;
import org.postgresql.Driver;

import br.com.germantech.ecf.Bootstrap;
import br.com.germantech.ecf.aplicacao.helpers.PropertiesHelper;

public abstract class GermantechEntityManager {

	private static Logger log = Logger.getLogger(GermantechEntityManager.class);
	
	private static EntityManagerFactory emf = null;
	private static Map<String, Object> properties = new HashMap<String, Object>();

	private static UnitOfWork uow;

	private static final ThreadLocal<EntityManager> ENTITY_MANAGER_CACHE = new ThreadLocal<EntityManager>();

	private synchronized static void init() {
		properties.put(PersistenceUnitProperties.TARGET_DATABASE, TargetDatabase.PostgreSQL);
		properties.put(PersistenceUnitProperties.JDBC_DRIVER, Driver.class.getCanonicalName());
		properties.put(PersistenceUnitProperties.JDBC_URL, PropertiesHelper.getProperty(PropertiesHelper.URL));
		properties.put(PersistenceUnitProperties.JDBC_USER, PropertiesHelper.getProperty(PropertiesHelper.USUARIO));
		properties.put(PersistenceUnitProperties.JDBC_PASSWORD, PropertiesHelper.getProperty(PropertiesHelper.SENHA));
		properties.put(PersistenceUnitProperties.CONNECTION_POOL_MIN, "1");
		properties.put(PersistenceUnitProperties.CONNECTION_POOL_MAX, "10");
		properties.put(PersistenceUnitProperties.CACHE_STATEMENTS, "true");
		properties.put(PersistenceUnitProperties.BATCH_WRITING, "JDBC");
		properties.put(PersistenceUnitProperties.CLASSLOADER, Bootstrap.class.getClassLoader());
		
		// Cria tabelas novas (mas não atualiza)
		if("true".equalsIgnoreCase(PropertiesHelper.getProperty(PropertiesHelper.GERAR_TABELAS))){
			log.info("Gerando tabelas...");
			properties.put(PersistenceUnitProperties.DDL_GENERATION, PersistenceUnitProperties.CREATE_OR_EXTEND);
		}
		
		// Cria os arquivos de geração do banco de dados
//		properties.put(PersistenceUnitProperties.CREATE_JDBC_DDL_FILE, "createDDL_ddlGeneration.jdbc");
//		properties.put(PersistenceUnitProperties.DDL_GENERATION_MODE, PersistenceUnitProperties.DDL_BOTH_GENERATION);
		
		properties.put("eclipselink.logging.level", "FINE");
		properties.put("eclipselink.logging.timestamp", "true");
		properties.put("eclipselink.logging.session", "true");
		properties.put("eclipselink.logging.thread", "true");
		properties.put("eclipselink.logging.exceptions", "true");
		
		emf = new PersistenceProvider().createEntityManagerFactory("gtech", properties);
	}

	/**
	 * Retorna um {@link EntityManager}. Caso não exista, cria um novo
	 */
	public synchronized static EntityManager getEntityManager() {
		EntityManager entityManager = ENTITY_MANAGER_CACHE.get();
		if (entityManager == null) {
			log.info("entityManager é null");
			init();
			ENTITY_MANAGER_CACHE.set(entityManager = emf.createEntityManager());
		}
		
		return entityManager;
	}
}