/*
 * Brazillian CNH number (Carteira Nacional de Habilitacao) is the License Driver number.
 * CNH numbers have 11 digits in total: 9 numbers followed by 2 check numbers that are being used for validation.
 */
$.validator.addMethod( "cnhBR", function( value ) {

  // Removing special characters from value
  value = value.replace( /([~!@#$%^&*()_+=`{}\[\]\-|\\:;'<>,.\/? ])+/g, "" );

  // Checking value to have 11 digits only
  if ( value.length !== 11 ) {
    return false;
  }

  var sum = 0, dsc = 0, firstChar,
		firstCN, secondCN, i, j, v;

  firstChar = value.charAt( 0 );

  if ( new Array( 12 ).join( firstChar ) === value ) {
    return false;
  }

  // Step 1 - using first Check Number:
  for ( i = 0, j = 9, v = 0; i < 9; ++i, --j ) {
    sum += +( value.charAt( i ) * j );
  }

  firstCN = sum % 11;
  if ( firstCN >= 10 ) {
    firstCN = 0;
    dsc = 2;
  }

  sum = 0;
  for ( i = 0, j = 1, v = 0; i < 9; ++i, ++j ) {
    sum += +( value.charAt( i ) * j );
  }

  secondCN = sum % 11;
  if ( secondCN >= 10 ) {
    secondCN = 0;
  } else {
    secondCN = secondCN - dsc;
  }

  return ( String( firstCN ).concat( secondCN ) === value.substr( -2 ) );

}, "Please specify a valid CNH number" );
