ice.fo.utils/String/formatTelText.js

import formatStringBlocks from './formatStringBlocks';

/**
 * Format Korean Tel
 */
export default function formatTelText(text) {
  let blocks = [];
  const delimiters = '-';

  if (text.startsWith('02')) {
    if (text.length >= 10) {
      blocks = [2, 4, 4];
    } else {
      blocks = [2, 3, 4];
    }
  } else if (text.length >= 11) {
    blocks = [3, 4, 4];
  } else {
    blocks = [3, 3, 4];
  }

  return formatStringBlocks(text, blocks, delimiters);
}