/*! @orchidjs/unicode-variants | https://github.com/orchidjs/unicode-variants | Apache License (v2) */
/**
 * Convert array of strings to a regular expression
 *	ex ['ab','a'] => (?:ab|a)
 * 	ex ['a','b'] => [ab]
 * @param {string[]} chars
 * @return {string}
 */
const arrayToPattern = chars => {
  chars = chars.filter(Boolean);

  if (chars.length < 2) {
    return chars[0] || '';
  }

  return maxValueLength(chars) == 1 ? '[' + chars.join('') + ']' : '(?:' + chars.join('|') + ')';
};
/**
 * @param {string[]} array
 * @return {string}
 */

const sequencePattern = array => {
  if (!hasDuplicates(array)) {
    return array.join('');
  }

  let pattern = '';
  let prev_char_count = 0;

  const prev_pattern = () => {
    if (prev_char_count > 1) {
      pattern += '{' + prev_char_count + '}';
    }
  };

  array.forEach((char, i) => {
    if (char === array[i - 1]) {
      prev_char_count++;
      return;
    }

    prev_pattern();
    pattern += char;
    prev_char_count = 1;
  });
  prev_pattern();
  return pattern;
};
/**
 * Convert array of strings to a regular expression
 *	ex ['ab','a'] => (?:ab|a)
 * 	ex ['a','b'] => [ab]
 * @param {Set<string>} chars
 * @return {string}
 */

const setToPattern = chars => {
  let array = toArray(chars);
  return arrayToPattern(array);
};
/**
 *
 * https://stackoverflow.com/questions/7376598/in-javascript-how-do-i-check-if-an-array-has-duplicate-values
 * @param {any[]} array
 */

const hasDuplicates = array => {
  return new Set(array).size !== array.length;
};
/**
 * https://stackoverflow.com/questions/63006601/why-does-u-throw-an-invalid-escape-error
 * @param {string} str
 * @return {string}
 */

const escape_regex = str => {
  return (str + '').replace(/([\$\(\)\*\+\.\?\[\]\^\{\|\}\\])/gu, '\\$1');
};
/**
 * Return the max length of array values
 * @param {string[]} array
 *
 */

const maxValueLength = array => {
  return array.reduce((longest, value) => Math.max(longest, unicodeLength(value)), 0);
};
/**
 * @param {string} str
 */

const unicodeLength = str => {
  return toArray(str).length;
};
/**
 * @param {any} p
 * @return {any[]}
 */

const toArray = p => Array.from(p);

export { arrayToPattern, escape_regex, hasDuplicates, maxValueLength, sequencePattern, setToPattern, toArray, unicodeLength };
//# sourceMappingURL=regex.js.map