import htmlToText from 'html-to-text'
import nodemailer from 'nodemailer'
import fs from 'fs'
import twig from 'twig'

export default class EmailService {
  static transporter: any = null

  static init() {
    if (this.isMocked()) {
      console.warn('> EmailService: WARNING: EMAIL IS MOCKED!')
    }
  }

  static getTransporter() {
    if (process.env.SMTP_HOST == undefined || process.env.SMTP_PORT == undefined) {
      throw new Error("Invalid SMTP config")
    }
    let config: any = {
      host: process.env.SMTP_HOST,
      port: parseInt(process.env.SMTP_PORT),
      secure: process.env.SMTP_SECURE == 'true'
    }
    if (process.env.SMTP_USERNAME !== undefined && process.env.SMTP_PASSWORD !== undefined) {
      config.auth = {
        user: process.env.SMTP_USERNAME,
        pass: process.env.SMTP_PASSWORD,
      }
    }
    console.log('> EmailService: Transport created ', config)
    return nodemailer.createTransport(config)
  }

  // static getMailgunClient(): Mailgun {
  //   return new Mailgun({
  //     apiKey: '4e64a894f18cc2fe10e4e4829b0048f3-7caa9475-241eee2c'
  //   })
  // }

  static nativeSend(params: any): Promise<any> {
    // return this.getMailgunClient().sendMessage('sandboxeb2300b9439e4fe7bd2cca8f52ac7bd6.mailgun.org', {
    //   from: params.from,
    //   to: params.to,
    //   subject: params.subject,
    //   text: params.text,
    //   html: params.html
    // })
    if (EmailService.transporter === null) {
      EmailService.transporter = EmailService.getTransporter()
    }
    return EmailService.transporter.sendMail(params)
  }

  static send(to: string, subject: string, templateName: string, templateParams: any): Promise<any> {
    const viewPath: string = __dirname + '/../views/emails/'
    const data: Buffer = fs.readFileSync(viewPath + templateName + '.twig')
    const html: string = twig.twig({
      // @ts-ignore
      allowInlineIncludes: true,
      data: data.toString()
    }).render(templateParams)
    const text: string = htmlToText.fromString(html, { wordwrap: 130 })
    
    // for now replace every email by a predefined one
    // console.info(to + ' replaced')
    // to = "spamfree@matthieubessat.fr"
    subject += " - Forum des associations 2020"

    return new Promise((resolve, reject) => {
      const config: any = {
        from: '"Forum des associations - Espace Condorcet Centre Social" <ne-pas-repondre@espacecondorcet.org>',
        to, subject, text, html
      }
      if (this.isMocked()) {
        delete config.html
        console.log(config)
        resolve()
      } else {
        this.nativeSend(config).then(res => {
          console.log('> A "' + templateName + '" email was sent to ' + to)
          resolve(res)
        }).catch(err => {
          console.log('> A "' + templateName + '" email failed to be sent to ' + to)
          console.error(err)
          reject()
        })
      }
    })
  }

  static getWebUiBaseUrl() {
    return process.env.WEB_UI_URL === undefined ? "WEB_UI_URL_NOT_FOUND" : process.env.WEB_UI_URL
  }
  
  static getBaseUrl() {
    return process.env.BASE_URL === undefined ? "BASE_URL_NOT_FOUND" : process.env.BASE_URL
  }

  static isMocked() {
    // WARNING ATTENTION REQUIRED
    // CUSTOM DESACTIVATION PLEASE ENABLE IN PRODUCTION
    return process.env.MOCK_EMAIL === "true"
  }

  static getAdminAddress() {
    return process.env.ADMIN_ADDRESS === undefined ? "ADMIN_ADDRESS_NOT_FOUND" : process.env.ADMIN_ADDRESS
  }
}