function createTokens(text: string): Array<string> {
  const tokenized: Array<string> = tokenizer.tokenize(text);
  const biGrams = NGrams.ngrams(tokenized, 2).map((words) => words.join(' '));
  const triGrams = NGrams.ngrams(tokenized, 3).map((words) => words.join(' ')) as Array<string>;
  const ngrams: Array<string> = _.flatten(tokenized.concat(biGrams, triGrams)) as Array<string>;
  const allPhrases = ngrams.map(phrase => phrase.toLowerCase());
  return allPhrases;
}

export function getLocationConfidence(text: string, searchLocation: string): number {
  let matchingCities = _.map(locations, (subLocations, key) => {
    // console.log(subLocations);
    return _.map(subLocations, (cities) => {
      // console.log(cities, searchLocation);
      const normalizedCities: Array<string> = cities.map(city => city.toLowerCase());
      return _.includes(normalizedCities, searchLocation.toLowerCase()) ? normalizedCities : null;
    });
  });

  const cityList = _.compact(_.flattenDeep<string>(matchingCities) as Array<string>);
  const allPhrases = createTokens(text);
  const matchingPhrase = _.intersection(allPhrases, cityList);

  const textTokenized: Array<string> = tokenizer.tokenize(text);
  const locationTokenized = tokenizer.tokenize(matchingPhrase[0]);

  return locationTokenized.length / textTokenized.length;
}

export function grabTopics(text: string): Promise<Intent> {
  const datesCompacted = runThroughClassifiers(text, dateClassifiers);
  const datesGrouped = _.groupBy(datesCompacted, 'topic');

  const specials = _.compact(tokenizer.tokenize(text).filter(token => !isNaN(parseInt(token, 10))));

  const intent: Intent = {
    action: null,
    details: {
      dates:  _.mapValues(datesGrouped, (classifications: Array<Classification>) => classifications.map(classification => _.startCase(classification.label))),
      specialWords: specials,
      locations: locatonExtractor(text),
    },
    topic: 'details',
  };

  // if (this && this.debugOn) { console.log('details intent', util.inspect(intent, { depth: null })); };

  return Promise.resolve(intent);
}