import { DataSource } from 'apollo-datasource';
import sendgrid from '@sendgrid/mail';
import logger from '@/logger';
import { DEFAULT_SEND_OPTIONS, SendOptions } from './types';

export default class TransactionalEmailSender extends DataSource {
  private enabled: boolean;
  constructor() {
    super();
    const apiKey = process.env.SENDGRID_API_KEY;
    // never enable in tests
    const enabled =
      !!process.env.EMAIL_SENDING_ENALBED && process.env.NODE_ENV !== 'test';
    if (enabled) {
      if (!apiKey) {
        throw new Error(
          'Cannot start TransactionalEmailSender without SENDGRID_API_KEY in environment'
        );
      } else {
        sendgrid.setApiKey(apiKey);
      }
    }
    this.enabled = enabled;
  }

  async send(input: SendOptions): Promise<void> {
    const { to, from, subject, text, html } = {
      ...DEFAULT_SEND_OPTIONS,
      html: input.text.replace(/\n/g, '<br />'),
      ...input,
    };
    const payload = {
      to,
      from,
      subject,
      text,
      html,
    };
    if (this.enabled) {
      await sendgrid.send(payload);
    } else {
      logger.info('Email sending disabld. Message that would have been sent:');
      logger.info(
        Object.entries(payload).reduce((prev, [key, value]) => {
          return `${prev}${key.toUpperCase()}: ${value}\n`;
        }, '')
      );
    }
  }
}