CreditCard.regex

(?x)
(?<![0-9])
(?:
[0-9]{12,19}                               # sequence of digits in the text between [12, 19] length
|
(?:[0-9]{4}[ -]){4}[0-9]{3}                # 4-4-4-4-3 pattern
|
(?:[0-9]{4}[ -]){3}[0-9]{4}                # 4-4-4-4 pattern
|
(?:[0-9]{4}[ -]){2}[0-9]{5}                # 4-4-5 pattern
|
[0-9]{4}[ -][0-9]{6}[ -][0-9]{4,5}         # 4-6-4 or 4-6-5 pattern
|
[0-9]{4}[ -][0-9]{5}[ -][0-9]{6}           # 4-5-6 pattern
|
[0-9]{6}[ -][0-9]{13}                      # 6-13 pattern
)
(?![0-9])