passport-config.js

const LocalStrategy = require("passport-local").Strategy;
const bcrypt = require("bcrypt");

const { getPatientByID, getDoctorByID, getAdminByID } = require("./database.js");
exports.initializePassport = async (passport) => {

    const authenticatePatient = async (req, email, password, done) => {
        let patient = await getPatientByID(email, true);
        if (patient == null) return done(null, false, req.flash("message", { type: "danger", title: "Patient Not Found", text: "Try creating an account." }));

        try {
            if (await bcrypt.compare(password, patient.password)) {
                return done(null, patient);
            } else return done(null, false, req.flash("message", { type: "danger", title: "Incorrect Credentials", text: "Incorrect password entered." }));
        } catch (err) {
            return done(err);
        }
    };

    const authenticateDoctor = async (req, email, password, done) => {
        let doctor = await getDoctorByID(email, true);
        if (doctor == null) return done(null, false, req.flash("message", { type: "danger", title: "Doctor Not Found", text: "Contact hospital admin." }));

        try {
            if (await bcrypt.compare(password, doctor.password)) {
                return done(null, doctor);
            } else return done(null, false, req.flash("message", { type: "danger", title: "Incorrect Credentials", text: "Invalid password entered." }));
        } catch (err) {
            return done(err);
        }
    };

    const authenticateAdmin = async (req, email, password, done) => {
        let admin = await getAdminByID(email, true);
        if (admin == null) return done(null, false, req.flash("message", { type: "danger", title: "Admin Not Found", text: "Contact website developer." }));

        try {
            if (await bcrypt.compare(password, admin.password)) {
                return done(null, admin);
            } else return done(null, false, req.flash("message", { type: "danger", title: "Incorrect Credentials", text: "Incorrect password entered." }));
        } catch (err) {
            return done(err);
        }
    };

    passport.use("patient", new LocalStrategy({ usernameField: "email", passReqToCallback: true }, authenticatePatient));
    passport.use("doctor", new LocalStrategy({ usernameField: "email", passReqToCallback: true }, authenticateDoctor));
    passport.use("admin", new LocalStrategy({ usernameField: "email", passReqToCallback: true }, authenticateAdmin));

    passport.serializeUser((user, done) => {
        done(null, { id: user.id, role: user.role });
    });
    passport.deserializeUser(async (data, done) => {
        let gotUser = null;
        if (data.role == "patient") gotUser = await getPatientByID(data.id);
        else if (data.role == "doctor") gotUser = await getDoctorByID(data.id);
        else if (data.role == "admin") gotUser = await getAdminByID(data.id);
        return done(null, gotUser);
    });
};