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Trigrams and closest match

Getting trigrams and searching the closest match

Tento skript by nemal byť nainštalovaný priamo. Je to knižnica pre ďalšie skripty, ktorú by mali používať cez meta príkaz // @require https://update.greatest.deepsurf.us/scripts/550221/1664485/Trigrams%20and%20closest%20match.js 

//GETTING TRIGRAMS:
function getTrigrams(value) {
  const trigrams = [];
  // Pad the string to handle edge cases for shorter strings and beginning/end trigrams
  const paddedValue = ' ' + value + ' '; 

  for (let i = 0; i < paddedValue.length - 2; i++) {
    trigrams.push(paddedValue.substring(i, i + 3));
  }
  return trigrams;
  }//Closing getTrigrams()-Function

  
function trigramSimilarity(stringA, stringB) {
  if (stringA === stringB) {
    return 1; // Strings are identical
  }

  const trigramsA = new Set(getTrigrams(stringA.toLowerCase())); // Convert to lowercase for case-insensitive comparison
  const trigramsB = new Set(getTrigrams(stringB.toLowerCase()));

  let commonTrigramsCount = 0;
  for (const trigram of trigramsA) {
    if (trigramsB.has(trigram)) {
      commonTrigramsCount++;
    }
  }

  const totalUniqueTrigrams = trigramsA.size + trigramsB.size - commonTrigramsCount;

  if (totalUniqueTrigrams === 0) {
    return 0; // Avoid division by zero if both strings are empty or result in no trigrams
  }

  return commonTrigramsCount / totalUniqueTrigrams;
  }//Closing-trigramSimilarity()-Function
  
  
  
  //SEARCHING CLOSEST MATCH:
  function findClosestMatchTrigrams(targetString, stringArray) {
        let closestMatch = null;
        let highestSimilarity = -1;

        for (const str of stringArray) {
            const similarity = trigramSimilarity(targetString, str);
            if (similarity > highestSimilarity) {
                highestSimilarity = similarity;
                closestMatch = str;
            }
        }

        return {
            closestMatch: closestMatch,
            similarityFraction: highestSimilarity
        };
    }//Closing-findClosestMatchTrigrams()-Function