package apiProject;

import javax.ws.rs.Path;

import javax.ws.rs.Path;
import java.sql.*;
import java.text.SimpleDateFormat;
import java.time.LocalDate;

import javax.ws.rs.*;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

import org.hibernate.Session;

import java.util.Date;

import com.auth0.jwt.JWT;
import com.auth0.jwt.algorithms.Algorithm;
import com.google.gson.Gson;

import domain.Alumno;
import domain.Usuario;
import util.Constants;
import util.HibernateUtil;

@Path("/users")
public class LoginRest {

    @POST
    @Path("/login")
    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.APPLICATION_JSON)
    public Response login(String json) {

        Gson gson = new Gson();
        Usuario user = gson.fromJson(json, Usuario.class);
        boolean userValidated = false;
        Usuario userFound;

        try {
            Session session = HibernateUtil.getSessionFactory().getCurrentSession();
            session.beginTransaction();

            String sql = "from Usuario WHERE username = :entryUser and password = :entryPw";

            userFound = (Usuario) session.createQuery(sql).setParameter("entryUser", user.getUsername()).setParameter("entryPw", user.getPassword()).getSingleResult();

            session.getTransaction().commit();

            session.close();

            if(userFound != null) {
                user.setToken(generateToken(userFound.getIdUsuario()));
                userValidated = true;
            }


        } catch (javax.persistence.NoResultException noResultException) {
            userFound = null;

        } catch (Exception e) {
            System.out.println(e);
            return Response.status(500).build();
        }

        user.setPassword("");
        if (userValidated) {
            return Response.status(200).entity(gson.toJson(user)).build();
        } else {
            return Response.status(401).build();
        }
    }

    private String generateToken(int id) throws Exception {
        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
        Date issuedDate = format.parse(LocalDate.now().toString());
        Date expirationDate = format.parse(LocalDate.now().plusMonths(1).toString());

        Algorithm algorithm = Algorithm.HMAC256(Constants.TOKEN_KEY);

        String token = JWT.create().withSubject(String.valueOf(id)).withIssuedAt(issuedDate)
                .withExpiresAt(expirationDate).sign(algorithm);

        return token;
    }
}