package cl.ipciisa.desarrolloComponentes.business.dao.impl;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;

import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.sql.DataSource;

import cl.ipciisa.desarrolloComponentes.resources.Resources;

public class DataSourceFactory {

    private static final String BD_DRIVER = "com.mysql.jdbc.Driver";
    private static final String BD = "prueba";
    private static final String BD_URL = "jdbc:mysql://localhost/" + BD;
    private static final String BD_USER = "root";
    private static final String BD_PASSWD = "root";


    /**
     * esta clase es la que decide a donde se conecta Si esta corriendo tomcat obtiene la conexion desde el contexto si no,
     * obtiene la conexion directamente
     *
     * @return
     * @throws DAOException
     */
    public static Connection getConnection() throws DAOException {

        Connection con = null;

        try {
            con = getConnectionFromContext();
        } catch (DAOException e) {
            con = getConnectionDirectly();
        } catch (SQLException e) {
            throw new DAOException(e.getMessage());
        }

        return con;
    }

    private static Connection getConnectionFromContext() throws DAOException, SQLException {

        InitialContext cxt = null;
        DataSource ds = null;

        try {

            cxt = new InitialContext();
            if (cxt == null)
                throw new DAOException("No hay contexto...!");

            ds = (DataSource) cxt.lookup("java:/comp/env/jdbc/DB_mySQL_Prueba");

            if (ds == null)
                throw new DAOException("No se ha encontrado conexión en el contexto!");

            Connection con = ds.getConnection();
            con.setAutoCommit(false);

            return con;

        } catch (NamingException e) {
            throw new DAOException(e.getMessage());
        }

    }

    private static Connection getConnectionDirectly() throws DAOException {

        Connection con = null;
        try {
            Class.forName(BD_DRIVER);
        } catch (ClassNotFoundException e) {
            System.out.println("Error : " + e.getMessage());
        }
        try {
            con = DriverManager.getConnection(BD_URL, BD_USER, BD_PASSWD);

            con.setAutoCommit(false);
            try {
                PreparedStatement pst = con.prepareStatement("SELECT 1 FROM DUAL");
                pst.executeQuery();
                pst.close();
            } catch (Exception e) {
                con.close();
            }
        } catch (SQLException sqle) {
            throw new DAOException("DataSourceFactory.getConnectionDirectly() failed!");
        }
        return con;
    }


    /**
     * Cierra la conecccion a la base de datos recibida como argumento solo si es distinta de la conexion estatica.
     *
     * @param con
     *            Coneccion a cerrar
     *
     */
    public static void desconectar(Connection con) {

        if (con != null)
            try {
                if (!con.isClosed())
                    con.close();
            } catch (SQLException sqle) {
                throw new RuntimeException("DataSourceFactory.desconetar() failed!");
            }
    }

}