package com.class3601.persistence;

import org.hibernate.CacheMode;
import org.hibernate.FlushMode;
import org.hibernate.HibernateException;
import org.hibernate.SQLQuery;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
//import org.hibernate.service.ServiceRegistryBuilder;


/**
* Utility class related to the persistence.
* Contains API used for Hibernate session management.
*
*
*/
public class HibernateUtil {

private static  SessionFactory sessionFactory;
private static ServiceRegistry serviceRegistry;
private static String DATABASE_NAME = "social";

//private static  Session session;

/**
* Builds Hibernate session factory based on the Hibernate configuration file.
*/
private static void buildSessionFactory(){

    if (sessionFactory == null) {
            try {
                Configuration configuration = new Configuration();
                configuration.setProperty("hibernate.connection.driver_class", "com.mysql.jdbc.Driver");  //Should read from file
                configuration.setProperty("hibernate.connection.url", "jdbc:mysql://localhost:3306/" + DATABASE_NAME + "?autoReconnect=true"); //Should read from file
                configuration.setProperty("show_sql", "false");
                configuration.setProperty("hibernate.dialect", "org.hibernate.dialect.MySQLDialect");
                configuration.setProperty("hibernate.connection.password", "social"); //Should read from file or prompt
                configuration.setProperty("hibernate.connection.username", "social"); //Should read from file or promtp
                configuration.setProperty("hibernate.transaction.factory_class", "org.hibernate.transaction.JDBCTransactionFactory");
                configuration.setProperty("hibernate.current_session_context_class", "thread");
                configuration.setProperty("hibernate.connection.autocommit", "true");
                configuration.configure();
                serviceRegistry = new StandardServiceRegistryBuilder().applySettings(
                        configuration.getProperties()).configure().build();
                sessionFactory = new MetadataSources( serviceRegistry ).buildMetadata().buildSessionFactory();
            } catch (HibernateException ex) {
                throw new RuntimeException("Exception building SessionFactory: " + ex.getMessage(), ex);
            }
        }
}

public static void clearSessionFactory(){

    if (sessionFactory != null) {
            try {
                sessionFactory.close();
            } catch (HibernateException ex) {
                sessionFactory = null;
                throw new RuntimeException("Exception closing SessionFactory: " + ex.getMessage(), ex);
            }
    }
    sessionFactory = null;
}

// Keeps track of all Hibernate threads
public static final ThreadLocal<Session> sessionThreadLocal = new ThreadLocal<Session>();

/**
  * Returns current Hibernate session based on the thread local.
  * First looks into thread local for a session. If found returns the session.
  * If not found creates new session and adds it to the thread local.
  *
  * @return
  * @throws HibernateException
  */
public synchronized static Session getCurrentSession() throws HibernateException {

    Session session = (Session) sessionThreadLocal.get();

      // Open a new Session, if this Thread has none yet
    if (session == null) {
        buildSessionFactory();
        session = sessionFactory.openSession();
        session.setCacheMode(CacheMode.IGNORE);
        session.setFlushMode(FlushMode.COMMIT);

        sessionThreadLocal.set(session);
    }
    return session;
}

/**
  * Closes current Hibernate session.
  * Looks for a current session in thread local, and if found closes the session.
  * Also sets thread local to null.
  *
  * @throws HibernateException
  */
public static void closeTheThreadLocalSession() throws HibernateException {

    Session session = (Session) sessionThreadLocal.get();
    sessionThreadLocal.set(null);
    if (session != null) {
        session.close();
    }
    session = null;

}


/**
* Used for initial table setup in the database.
*
* @param sql
* @return
*/
public static synchronized boolean executeSQLQuery(String sql) {

    Session session = null;
    Transaction transaction = null;

    try {
        session = getCurrentSession();
        transaction = session.beginTransaction();
        SQLQuery query = session.createSQLQuery(sql);
        query.executeUpdate();
        transaction.commit();
    } catch (Exception exception) {
        exception.printStackTrace();
    }
    finally {
        closeTheThreadLocalSession();
    }
    return true;
}

public static void setupTables() {
	HibernateDatabaseCounterManager.getDefault().setupTable();
	HibernateDatabaseClientManager.getDefault().setupTable();
}
}