mirror of https://github.com/askn/faker.git
67 lines
1.7 KiB
Crystal
67 lines
1.7 KiB
Crystal
module Faker
|
|
class Code < Base
|
|
RBI = %w[01 10 30 33 35 44 45 49 50 51 52 53 54 86 91 98 99]
|
|
|
|
def self.isbn(base : Int32 = 10)
|
|
case base
|
|
when 10 then generate_base10_isbn
|
|
when 13 then generate_base13_isbn
|
|
else raise ArgumentError.new("base must be 10 or 13")
|
|
end
|
|
end
|
|
|
|
def self.imei
|
|
str = Array.new(15, 0)
|
|
sum = 0
|
|
len = 15
|
|
|
|
# Fill in the first two values of the string based with the specified prefix.
|
|
arr = RBI.sample(Faker.rng)
|
|
str[0] = arr[0].to_i
|
|
str[1] = arr[1].to_i
|
|
pos = 2
|
|
|
|
# Fill all the remaining numbers except for the last one with random values.
|
|
while pos < (len - 1)
|
|
str[pos] = Faker.rng.rand(0..9)
|
|
pos += 1
|
|
end
|
|
|
|
# Calculate the Luhn checksum of the values thus far
|
|
len_offset = (len + 1) % 2
|
|
(0..(len - 1)).each do |position|
|
|
if (position + len_offset).odd?
|
|
t = str[position] * 2
|
|
|
|
t -= 9 if t > 9
|
|
|
|
sum += t
|
|
else
|
|
sum += str[position]
|
|
end
|
|
end
|
|
str[len - 1] = (10 - (sum % 10)) % 10
|
|
|
|
str.join("")
|
|
end
|
|
|
|
private def self.generate_base10_isbn
|
|
values = Faker.regexify(/\d{9}/)
|
|
remainder = sum(values) { |value, index| (index + 1) * value.to_i } % 11
|
|
values += "-#{remainder == 10 ? 'X' : remainder}"
|
|
end
|
|
|
|
private def self.generate_base13_isbn
|
|
values = Faker.regexify(/\d{12}/)
|
|
remainder = sum(values) { |value, index| index.even? ? value.to_i : value.to_i * 3 } % 10
|
|
values += "-#{(10 - remainder) % 10}"
|
|
end
|
|
|
|
private def self.sum(values)
|
|
values.split(//).each_with_index.reduce(0) do |sum, (value, index)|
|
|
sum + yield(value, index)
|
|
end
|
|
end
|
|
end
|
|
end
|