import { Router } from 'express'
import passport from 'passport'
import LDAPStrategy from 'passport-ldapauth'

import { config } from '../../../config'
import { User } from '../../../models'
import { logger } from '../../../logger'
import { urlencodedParser } from '../../utils'
import { errors } from '../../../errors'
import { AuthMiddleware } from '../interface'

export const LdapMiddleware: AuthMiddleware = {
  getMiddleware (): Router {
    const LdapAuth = Router()

    passport.use(new LDAPStrategy({
      server: {
        url: config.ldap.url || null,
        bindDN: config.ldap.bindDn || null,
        bindCredentials: config.ldap.bindCredentials || null,
        searchBase: config.ldap.searchBase || null,
        searchFilter: config.ldap.searchFilter || null,
        searchAttributes: config.ldap.searchAttributes || null,
        tlsOptions: config.ldap.tlsOptions || null,
	starttls: config.ldap.starttls || null
      }
    }, function (user, done) {
      let uuid = user.uidNumber || user.uid || user.sAMAccountName || undefined
      if (config.ldap.useridField && user[config.ldap.useridField]) {
        uuid = user[config.ldap.useridField]
      }

      if (typeof uuid === 'undefined') {
        throw new Error('Could not determine UUID for LDAP user. Check that ' +
          'either uidNumber, uid or sAMAccountName is set in your LDAP directory ' +
          'or use another unique attribute and configure it using the ' +
          '"useridField" option in ldap settings.')
      }

      let username = uuid
      if (config.ldap.usernameField && user[config.ldap.usernameField]) {
        username = user[config.ldap.usernameField]
      }

      const profile = {
        id: 'LDAP-' + uuid,
        username: username,
        displayName: user.displayName,
        emails: user.mail ? Array.isArray(user.mail) ? user.mail : [user.mail] : [],
        avatarUrl: null,
        profileUrl: null,
        provider: 'ldap'
      }
      const stringifiedProfile = JSON.stringify(profile)
      User.findOrCreate({
        where: {
          profileid: profile.id.toString()
        },
        defaults: {
          profile: stringifiedProfile
        }
      }).then(function ([user, _]) {
        if (user) {
          let needSave = false
          if (user.profile !== stringifiedProfile) {
            user.profile = stringifiedProfile
            needSave = true
          }
          if (needSave) {
            user.save().then(function () {
              logger.debug(`user login: ${user.id}`)
              return done(null, user)
            })
          } else {
            logger.debug(`user login: ${user.id}`)
            return done(null, user)
          }
        }
      }).catch(function (err) {
        logger.error('ldap auth failed: ' + err)
        return done(err, null)
      })
    }))

    LdapAuth.post('/auth/ldap', urlencodedParser, function (req, res, next) {
      if (!req.body.username || !req.body.password) return errors.errorBadRequest(res)
      passport.authenticate('ldapauth', {
        successReturnToOrRedirect: config.serverURL + '/',
        failureRedirect: config.serverURL + '/',
        failureFlash: true
      })(req, res, next)
    })

    return LdapAuth
  }
}