'use strict';

const formData = require('form-data');
const Mailgun = require('mailgun.js');
const { removeUndefined } = require('@strapi/utils');

const optionsMap = {
  apiKey: { field: 'key', fn: value => value },
  domain: { field: 'domain', fn: value => value },
  host: { field: 'url', fn: value => `https://${value || 'api.mailgun.net'}` },
};

const convertProviderOptions = (providerOptions = {}) => {
  const newOptions = {};
  if (typeof providerOptions === 'object') {
    Object.keys(providerOptions).forEach(key => {
      if (Object.keys(optionsMap).includes(key)) {
        newOptions[optionsMap[key].field] = optionsMap[key].fn(providerOptions[key]);
      }
    });
  }
  return newOptions;
};

module.exports = {
  init(providerOptions = {}, settings = {}) {
    const mailgun = new Mailgun(formData);
    const mg = mailgun.client({ username: 'api', ...convertProviderOptions(providerOptions) });

    return {
      send(options) {
        return new Promise((resolve, reject) => {
          const { from, to, cc, bcc, replyTo, subject, text, html, ...rest } = options;

          let data = {
            from: from || settings.defaultFrom,
            to,
            cc,
            bcc,
            'h:Reply-To': replyTo || settings.defaultReplyTo,
            subject,
            text,
            html,
            ...rest,
          };

          mg.messages
            .create(providerOptions.domain, removeUndefined(data))
            .then(() => resolve())
            .catch(err => reject(err));
        });
      },
    };
  },
};