Coding Exercise for JS position

words-in-tiles.js

const tilePoints = {
  a: 10,
  b: 5,
  c: 2,
  t: 1,
  // TODO - add more tile points for different letters
  _: 0,
};

/**
 * Returns the amount of points given for a term if it is
 * contained within a given set a tiles.  Otherwise, will return error
 * if it is NOT contained in 
 *
 * @param {string} term - search term being used
 * @param {string[]} tiles - given tiles for user
 *
 * @returns {number} tile points for term if contained in tiles or ERROR
 */
function tilePointsWithTerm(term, tiles) {
  // create simple count-map of available tiles
  const tilesCount = tiles.reduce((countObj, tile) => {
    countObj[tile] = (countObj[tile] || 0) + 1;

    return countObj;
  }, {});

  // return the total points of term (or ERROR) with available count-map
  return term
    .split('')
    .reduce((finalPoints, char) => {
      const takeChar = tilesCount[char] ? char :
        tilesCount['_'] ? '_' :
        'END';

      if (takeChar === 'END') throw Error('NOT POSSIBLE!');

      finalPoints += tilePoints[takeChar];
      tilesCount[takeChar] = tilesCount[takeChar] - 1;

      return finalPoints;
    }, 0);
}

/**
 * Returns the term with the highest amount of points, or UNDEFINED if
 * no term exists within the given tiles
 *
 * @param {string[]} terms
 * @param {string[]} tiles
 *
 * @returns {string|undefined} term within tiles with higest values (points)
 */
function bestTermWithTiles(terms, tiles) {
  return terms
    .flatMap(term => {
      try {
        return [[term, tilePointsWithTerm(term, tiles)]];
      } catch (e) {
        return [];
      }
    })
    .sort((a, b) => b[1] - a[1])[0]?.[0];
}