gistfile1.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Data.SQLite;
/* create table usuarios(
 *  username text primary key,
 *  password text not null,
 *  ultima_sesion text not null,
 *  fecha_creacion text not null
 *  )
 */
namespace ciberboro
{
    class usuario
    {
        conexion con;
        String username;

        String password;
        DateTime ultimaSesion;
        DateTime fechaCreacion;
        SQLiteCommand comando;
        bool logueado = false;

        public usuario(String username, String password)
        {
            //procedimiento para crear un usuario
            this.username = username;
            this.password = password;
            this.fechaCreacion = DateTime.Today;
            this.ultimaSesion = DateTime.Today;
        }

        public usuario(string username)
        {
            //para leer un usuario
            this.username = username;
            string query = "select username, password, ultima_sesion from usuario " +
                "where username = @username;";

            con = new conexion();
            comando = new SQLiteCommand(query, con.ConexionSql);

            SQLiteParameter paramUsername = new SQLiteParameter("@username", this.username);
            comando.Parameters.Add(paramUsername);

            SQLiteDataReader dr;
            dr = comando.ExecuteReader();

            if (dr.HasRows == true)
            {
                while (dr.Read() == true)
                {
                    this.password = dr[1].ToString(); //TODO: check this shit out!
                    //this.ultimaSesion = DateTime.Parse(dr[2].ToString());
                  //  this.fechaCreacion = DateTime.Parse(dr[3].ToString());
                }
               
            }
            else
            {
                throw new NullReferenceException("no existe el usuario");
            }
        }


        //propiedades

        public String Username
        {
            get { return username; }
            set { username = value; }
        }

        public bool guardar()
        {
            //procedimiento para guardar el usuario.
            string query;
           /*if (this.logueado == true)
            {
              query = "update usuarios set password = '@password', " +
                    "fecha_creacion = '@fecha_creacion', ultima_sesion = '@ultima_sesion' where username = '@user_actual';";
            }
            else
            {*/
                query = "INSERT INTO usuario(id_usuario, username, password, fecha_registro, ultima_sesion) VALUES(" +
                    "null, @username, @password, @fecha_creacion, @ultima_sesion);"; 

            //}
            con = new conexion();
            comando = new SQLiteCommand(query, con.ConexionSql);

            SQLiteParameter paramUsername = new SQLiteParameter("@username", this.username);
            SQLiteParameter paramPassword = new SQLiteParameter("@password", this.password);
            SQLiteParameter paramFecha = new SQLiteParameter("@fecha_creacion", this.fechaCreacion.ToString());
            SQLiteParameter paramUltimaSesion = new SQLiteParameter("@ultima_sesion", this.ultimaSesion.ToString());

            comando.Parameters.Add(paramUsername);
            comando.Parameters.Add(paramPassword);
            comando.Parameters.Add(paramFecha);
            comando.Parameters.Add(paramUltimaSesion);
            try
            {
                comando.ExecuteNonQuery();
                return true;
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
                return false;
            }
        }

        public bool login()
        {
            //proceso para loguearse
            string query = "select username, password, ultima_sesion from usuario " +
                "where username = @username and password = @password;";

            con = new conexion();
            comando = new SQLiteCommand(query, con.ConexionSql);

            SQLiteParameter paramUsername = new SQLiteParameter("@username", this.username);
            SQLiteParameter paramPassword = new SQLiteParameter("@password", this.password);

            comando.Parameters.Add(paramUsername);
            comando.Parameters.Add(paramPassword);

            SQLiteDataReader dr;
            dr = comando.ExecuteReader();

            if (dr.HasRows == true)
            {
                while (dr.Read() == true)
                {
                    this.username = dr[0].ToString();
                    this.password = dr[1].ToString();
                    //this.ultimaSesion = DateTime.Parse(dr[2].ToString());
                    //this.fechaCreacion = DateTime.Parse(dr[3].ToString());
                }
                this.logueado = true;

                query = "update usuario set ultima_sesion = '" + DateTime.Now.ToString() + "' where username = @username";
                comando = new SQLiteCommand(query, con.ConexionSql);
                comando.Parameters.Add(paramUsername);
                comando.ExecuteNonQuery();

                return true;
            }
            else
            {
                return false;
            }

            
        }

        public bool borrar()
        {
            con = new conexion();
            string query = "delete from usuarios where username = @username;";
            comando = new SQLiteCommand(query, con.ConexionSql);

            comando.Parameters.Add(new SQLiteParameter("@username", this.username));

            
            try
            {
                comando.ExecuteNonQuery();
                return true;
            }
            catch (Exception e)
            {
                Console.Write(e.Message);
                return false;
            }
        }
    }
}