const Model = require('objection').Model
const fs = require('fs-extra')
const path = require('path')
const _ = require('lodash')
const yaml = require('js-yaml')
const commonHelper = require('../helpers/common')

/* global WIKI */

/**
 * Authentication model
 */
module.exports = class Authentication extends Model {
  static get tableName() { return 'authentication' }
  static get idColumn() { return 'key' }

  static get jsonSchema () {
    return {
      type: 'object',
      required: ['key'],

      properties: {
        key: {type: 'string'},
        selfRegistration: {type: 'boolean'}
      }
    }
  }

  static get jsonAttributes() {
    return ['config', 'domainWhitelist', 'autoEnrollGroups']
  }

  static async getStrategy(key) {
    return WIKI.models.authentication.query().findOne({ key })
  }

  static async getStrategies() {
    const strategies = await WIKI.models.authentication.query().orderBy('order')
    return strategies.map(str => ({
      ...str,
      domainWhitelist: _.get(str.domainWhitelist, 'v', []),
      autoEnrollGroups: _.get(str.autoEnrollGroups, 'v', [])
    }))
  }

  static async getStrategiesForLegacyClient() {
    const strategies = await WIKI.models.authentication.query().select('key', 'selfRegistration')
    let formStrategies = []
    let socialStrategies = []

    for (let stg of strategies) {
      const stgInfo = _.find(WIKI.data.authentication, ['key', stg.key]) || {}
      if (stgInfo.useForm) {
        formStrategies.push({
          key: stg.key,
          title: stgInfo.title
        })
      } else {
        socialStrategies.push({
          ...stgInfo,
          ...stg,
          icon: await fs.readFile(path.join(WIKI.ROOTPATH, `assets/svg/auth-icon-${stg.key}.svg`), 'utf8').catch(err => {
            if (err.code === 'ENOENT') {
              return null
            }
            throw err
          })
        })
      }
    }

    return {
      formStrategies,
      socialStrategies
    }
  }

  static async refreshStrategiesFromDisk() {
    try {
      const dbStrategies = await WIKI.models.authentication.query()

      // -> Fetch definitions from disk
      const authDirs = await fs.readdir(path.join(WIKI.SERVERPATH, 'modules/authentication'))
      WIKI.data.authentication = []
      for (let dir of authDirs) {
        const defRaw = await fs.readFile(path.join(WIKI.SERVERPATH, 'modules/authentication', dir, 'definition.yml'), 'utf8')
        const def = yaml.safeLoad(defRaw)
        WIKI.data.authentication.push({
          ...def,
          props: commonHelper.parseModuleProps(def.props)
        })
      }

      for (const strategy of dbStrategies) {
        let newProps = false
        const strategyDef = _.find(WIKI.data.authentication, ['key', strategy.strategyKey])
        if (!strategyDef) {
          await WIKI.models.authentication.query().delete().where('key', strategy.key)
          WIKI.logger.info(`Authentication strategy ${strategy.strategyKey} was removed from disk: [ REMOVED ]`)
          continue
        }
        strategy.config = _.transform(strategyDef.props, (result, value, key) => {
          if (!_.has(result, key)) {
            _.set(result, key, value.default)
            // we have some new properties added to an existing auth strategy to write to the database
            newProps = true
          }
          return result
        }, strategy.config)

        // Fix pre-2.5 strategies displayName
        if (!strategy.displayName) {
          await WIKI.models.authentication.query().patch({
            displayName: strategyDef.title
          }).where('key', strategy.key)
        }
        // write existing auth model to database with new properties and defaults
        if (newProps) {
          await WIKI.models.authentication.query().patch({
            config: strategy.config
          }).where('key', strategy.key)
        }
      }

      WIKI.logger.info(`Loaded ${WIKI.data.authentication.length} authentication strategies: [ OK ]`)
    } catch (err) {
      WIKI.logger.error(`Failed to scan or load new authentication providers: [ FAILED ]`)
      WIKI.logger.error(err)
    }
  }
}