levenshteinDistance.js

function levenshteinDistance(str1 = '', str2 = '') {
  const track = Array(str2.length + 1).fill(null).map(() =>
    Array(str1.length + 1).fill(null));
  for (let i = 0; i <= str1.length; i += 1) {
    track[0][i] = i;
  }
  for (let j = 0; j <= str2.length; j += 1) {
    track[j][0] = j;
  }
  for (let j = 1; j <= str2.length; j += 1) {
    for (let i = 1; i <= str1.length; i += 1) {
      const indicator = str1[i - 1] === str2[j - 1] ? 0 : 1;
      track[j][i] = Math.min(
        track[j][i - 1] + 1, // deletion
        track[j - 1][i] + 1, // insertion
        track[j - 1][i - 1] + indicator, // substitution
      );
    }
  }
  return track[str2.length][str1.length];
};

function getClosestOption(str, array) {
  if (array.includes(str)) {
    return str;
  }
  let minDistance = Infinity;
  let option = str;
  array.forEach(str2 => {
    const distance = levenshteinDistance(str, str2);
    if (distance < minDistance) {
      minDistance = distance;
      option = str2;
    }
  });
  return option;
}