// session.js
// Copyright (C) 2021 Digital Telepresence, LLC
// License: Apache-2.0

'use strict';

const util = require('util');

const passport = require('passport');

const { SiteError, SiteLog } = require('../../lib/site-lib');

class SessionService {

  constructor (dtp) {
    this.dtp = dtp;
    this.log = new SiteLog(dtp, `svc:${module.exports.slug}`);
  }

  async start ( ) {
    this.log.info(`starting ${module.exports.name} service`);
    passport.serializeUser(this.serializeUser.bind(this));
    passport.deserializeUser(this.deserializeUser.bind(this));
  }

  async stop ( ) {
    this.log.info(`stopping ${module.exports.name} service`);
  }

  middleware ( ) {
    return async (req, res, next) => {
      res.locals.user = req.user;
      res.locals.query = req.query;

      if (req.user) {
        if (req.user.flags.isAdmin) {
          res.locals.config = this.dtp.config;
          res.locals.session = req.session;
          res.locals.util = util;
        }
      }

      return next();
    };
  }

  authCheckMiddleware (options) {
    options = Object.assign({
      requireLogin: true,
      requireAdmin: false,
    }, options);
    return async (req, res, next) => {
      if (options.requireLogin && !req.user) {
        return next(new SiteError(403, 'Must sign in to proceed'));
      }
      if (options.requireAdmin && (!req.user || !req.user.flags.isAdmin)) {
        return next(new SiteError(403, 'Administrator privileges are required'));
      }
      return next();
    };
  }

  async serializeUser (user, done) {
    return done(null, user._id);
  }

  async deserializeUser (userId, done) {
    const { user: userService } = this.dtp.services;
    try {
      const user = await userService.getUserAccount(userId);
      return done(null, user);
    } catch (error) {
      this.log.error('failed to deserialize user from session', { error });
      return done(null, null);
    }
  }
}

module.exports = {
  slug: 'session',
  name: 'session',
  create: (dtp) => { return new SessionService(dtp); },
};