import bcrypt from 'bcrypt';

import { getDB } from '../../database';
import dbTables from '../../constants/db_tables';
import roles from '../../constants/roles';
import { createToken } from '../../auth/jwt';

/**
 * Funksioni qe menaxhon log-in ne sistem.
 * Ne trupin e kerkeses HTTP vjen email dhe password.
 */

export const logIn = (request, response) => {
  const db = getDB();
  const sessionToken = createToken({
    email: request.body.email,
    password: request.body.password,
  });


  // Query per te kerkuar perdoruesin ne baze te emailit
  const queryUser = `
    SELECT *
    FROM ${dbTables.PERDORUES}
    WHERE ${dbTables.PERDORUES}.email = ${db.escape(request.body.email)}
  `;

  // Ekzekutimi i query
  db.query(queryUser, async (error, results, fields) => {

    // Kontrolli nese ekziston perdorues me emailin e marre
    if (results && results.length > 0) {
      const user = results[0];

      // Verifikimi i passwordit (krahasohen versionet e hashuara)
      const passwordCorrect = await bcrypt.compare(request.body.password, user.password);

      if (passwordCorrect) {

        /**
         * Jemi ne situaten kur perdoruesi eshte autentikuar me sukses.
         * Ne baze te rolit, bejme dhe nje query tjeter te tabela perkatese
         * (ADMINISTRATOR; SEKRETAR; STUDENT ose PEDAGOG) per te marre gjithe
         * objektin dhe per tia kthyer perdoruesit.
         */

        let queryFullUserObject;

        if (user.roli === roles.ADMINISTRATOR) {
          queryFullUserObject = `
            SELECT *
            FROM ${dbTables.ADMINISTRATOR}
            WHERE ${dbTables.ADMINISTRATOR}.id_perdorues = ${user.id}
          `;
        } else if (user.roli === roles.SECRETARY) {
          queryFullUserObject = `
            SELECT *
            FROM ${dbTables.SEKRETAR}
            WHERE ${dbTables.SEKRETAR}.id_perdorues = ${user.id}
          `;
        } else if (user.roli === roles.PEDAGOGUE) {
          queryFullUserObject = `
            SELECT *
            FROM ${dbTables.PEDAGOG}
            WHERE ${dbTables.PEDAGOG}.id_perdorues = ${user.id}
          `;
        } else if (user.roli === roles.STUDENT) {
          queryFullUserObject = `
            SELECT *
            FROM ${dbTables.STUDENT}
            WHERE ${dbTables.STUDENT}.id_perdorues = ${user.id}
          `;
        }

        db.query(queryFullUserObject, (error2, results2, fields2) => {
          if (results2 && results2.length > 0) {
            const fullUserObject = results2[0];

            // Kthimi i objektit te plote te perdoruesit bashke me tokenin e sesionit
            response.json({
              email: user.email,
              role: user.role,
              token: sessionToken,
              ...fullUserObject,
            });
          } else  {
            response.status(401).json({
              code: 401,
              message: 'Problem në ekzekutimin e kërkesës. Provoni përsëri!',
            });
          }
        });
      } else {
        response.status(401).json({
          code: 401,
          message: 'Fjalëkalimi është i gabuar',
        });
      }
    } else {
      response.status(401).json({
        code: 401,
        message: 'Përdoruesi me email-in e dhënë nuk ekziston',
      });
    }
  });
};