javascript common formatters

formatters.ts

const normalizePhone = (value: string): string => {
  if (!value) return '';
  let newNumber = value.replace(/\D/g, '');
  newNumber = newNumber.substring(0, 11);
  newNumber = newNumber.replace(/^(\d{2})(\d)/g, '$1 $2');
  newNumber = newNumber.replace(/(\d)(\d{4})$/, '$1-$2');
  return newNumber;
};

const normalizeDocument = (value: string): string => {
  if (!value) return '';
  let newVal = value.replace(/\D/g, '');
  if (newVal.length <= 11) {
    newVal = normalizeCPF(newVal);
  } else {
    newVal = normalizeCNPJ(newVal);
  }
  return newVal;
};

const normalizeCPF = (value: string): string => {
  if (!value) return '';
  let newVal = value.replace(/\D/g, '');
  newVal = newVal.substring(0, 11);
  newVal = newVal.replace(/^(\d{3})(\d)(.*)/, '$1.$2$3');
  newVal = newVal.replace(/^(\d{3}\.\d{3})(\d)(.*)/, '$1.$2$3');
  newVal = newVal.replace(/^(\d{3}\.\d{3}\.\d{3})(\d)(.*)/, '$1-$2$3');
  return newVal;
};

const normalizeCNPJ = (value: string): string => {
  if (!value) return '';
  let newVal = value.replace(/\D/g, '');
  newVal = newVal.substring(0, 14);
  newVal = newVal.replace(/(\d{2})(\d)(.*)/, '$1.$2$3');
  newVal = newVal.replace(/(\d{2}\.\d{3})(\d)(.*)/, '$1.$2$3');
  newVal = newVal.replace(/(\d{2}\.\d{3}\.\d{3})(\d)(.*)/, '$1/$2$3');
  newVal = newVal.replace(/(\d{2}\.\d{3}\.\d{3}\/\d{4})(\d)(.*)/, '$1-$2$3');
  return newVal;
};

/**
* This preserves the caret position on inputs after transformation. 
* Call it on the onChange handler before returning the value:
* onChange(e)=>{
*  keepCaretPositionOnChange(e)
*  const newValue = transformValueSomehow(e.target.value);
*  //return or update the input value   
* }
**/    
export const keepCaretPositionOnChange = (
  evt: ChangeEvent<HTMLInputElement>,
) => {
  const caret = evt.target.selectionStart;
  const element = evt.target;
  window.requestAnimationFrame(() => {
    element.selectionStart = caret;
    element.selectionEnd = caret;
  });
};
    

export default {
  normalizePhone,
  normalizeDocument,
  normalizeCPF,
  normalizeCNPJ,
};