import Storage from '../../utils/Storage';
import jsonexport from 'jsonexport/dist';
import { dissoc, values } from 'ramda';

const SERVERS_STORAGE_KEY = 'servers';

const saveCsv = (window, csv) => {
  const { navigator, document } = window;
  const filename = 'shlink-servers.csv';
  const blob = new Blob([csv], { type: 'text/csv;charset=utf-8;' });

  // IE10 and IE11
  if (navigator.msSaveBlob) {
    navigator.msSaveBlob(blob, filename);
    return;
  }

  // Modern browsers
  const link = document.createElement('a');
  const url = URL.createObjectURL(blob);
  link.setAttribute('href', url);
  link.setAttribute('download', filename);
  link.style.visibility = 'hidden';
  document.body.appendChild(link);
  link.click();
  document.body.removeChild(link);
};

export class ServersExporter {
  constructor(storage, window, jsonexport) {
    this.storage = storage;
    this.window = window;
    this.jsonexport = jsonexport;
  }

  exportServers = async () => {
    const servers = values(this.storage.get(SERVERS_STORAGE_KEY) || {}).map(
      dissoc('id')
    );

    try {
      const csv = await new Promise((resolve, reject) => {
        this.jsonexport(servers, (err, csv) => err ? reject(err) : resolve(csv));
      });

      saveCsv(this.window, csv);
    } catch (e) {
      // FIXME Handle error
      console.error(e);
    }
  };
}

export default new ServersExporter(Storage, global.window, jsonexport);