69 lines
1.5 KiB
Go
69 lines
1.5 KiB
Go
package fake
|
|
|
|
import (
|
|
"strings"
|
|
|
|
"strconv"
|
|
)
|
|
|
|
type creditCard struct {
|
|
vendor string
|
|
length int
|
|
prefixes []int
|
|
}
|
|
|
|
var creditCards = map[string]creditCard{
|
|
"visa": {"VISA", 16, []int{4539, 4556, 4916, 4532, 4929, 40240071, 4485, 4716, 4}},
|
|
"mastercard": {"MasterCard", 16, []int{51, 52, 53, 54, 55}},
|
|
"amex": {"American Express", 15, []int{34, 37}},
|
|
"discover": {"Discover", 16, []int{6011}},
|
|
}
|
|
|
|
// CreditCardType returns one of the following credit values:
|
|
// VISA, MasterCard, American Express and Discover
|
|
func CreditCardType() string {
|
|
n := len(creditCards)
|
|
var vendors []string
|
|
for _, cc := range creditCards {
|
|
vendors = append(vendors, cc.vendor)
|
|
}
|
|
|
|
return vendors[r.Intn(n)]
|
|
}
|
|
|
|
// CreditCardNum generated credit card number according to the card number rules
|
|
func CreditCardNum(vendor string) string {
|
|
if vendor != "" {
|
|
vendor = strings.ToLower(vendor)
|
|
} else {
|
|
var vendors []string
|
|
for v := range creditCards {
|
|
vendors = append(vendors, v)
|
|
}
|
|
vendor = vendors[r.Intn(len(vendors))]
|
|
}
|
|
card := creditCards[vendor]
|
|
prefix := strconv.Itoa(card.prefixes[r.Intn(len(card.prefixes))])
|
|
num := []rune(prefix)
|
|
for i := 0; i < card.length-len(prefix); i++ {
|
|
num = append(num, genCCDigit(num))
|
|
}
|
|
return string(num)
|
|
}
|
|
|
|
func genCCDigit(num []rune) rune {
|
|
sum := 0
|
|
for i := len(num) - 1; i >= 0; i-- {
|
|
n := int(num[i])
|
|
if i%2 != 0 {
|
|
sum += n
|
|
} else {
|
|
if n*2 > 9 {
|
|
sum += n*2 - 9
|
|
} else {
|
|
sum += n * 2
|
|
}
|
|
}
|
|
}
|
|
return rune(((sum/10+1)*10 - sum) % 10)
|
|
}
|