romaji-fuzzy-search/dist/index.js

Generates a regular expression for "Romaji Fuzzy Search"

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.convertToRegExp = exports.romajiDictionary = exports.indexedRomajiDictionary = void 0;
const romaji_dictionary_1 = require("./romaji-dictionary");
exports.indexedRomajiDictionary = romaji_dictionary_1.indexedRomajiDictionary;
var romaji_dictionary_2 = require("./romaji-dictionary");
Object.defineProperty(exports, "romajiDictionary", { enumerable: true, get: function () { return romaji_dictionary_2.romajiDictionary; } });
/**
 * @see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions#escaping
 */
const escapeRegExp = (str) => {
    return str.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
};
const convertToRegExp = (str, indexedDictionary = exports.indexedRomajiDictionary) => {
    const createRomajiPattern = (romajiDictionaryItem) => `(?:${romajiDictionaryItem.map(escapeRegExp).join('|')})`;
    let pointer = 0;
    let result = '';
    let firstCharacter = undefined;
    while (firstCharacter = str[pointer]) {
        if (firstCharacter === undefined) {
            break;
        }
        let phrase = firstCharacter;
        if (str[pointer + 1]) {
            phrase += str[pointer + 1];
        }
        if (str[pointer + 2]) {
            phrase += str[pointer + 2];
        }
        let replaced = false;
        for (let phraseLength = 3; phraseLength >= 1; phraseLength--) {
            const replacement = indexedDictionary[phrase.slice(0, phraseLength)];
            if (replacement) {
                result += createRomajiPattern(replacement);
                pointer += phraseLength;
                replaced = true;
                break;
            }
        }
        if (replaced) {
            continue;
        }
        result += escapeRegExp(firstCharacter);
        pointer++;
    }
    return result;
};
exports.convertToRegExp = convertToRegExp;