ssn.rb

# we use the match method to extract the data from original string
# find the gender
# find the birth year
# find the birth month
# find the dept
# validate the number
require 'date'
DEPT = {
  75 => "Paris",
  76 => "Seine-Maritime"
}
SSN_REG = /^(?<gender>1|2)(?<year>\d{2})(?<month>\d{2})(?<department>\d{2})(\d{6})(?<key>\d{2})$/

def ssn_info(ssn)
  #Return => "a man, born in March, 1986 in Paris."
  ssn.gsub!(" ",'')
  data = ssn.match(SSN_REG)
  gender = data[:gender].to_i == 1 ?  "man" : "woman"
  year = data[:year].to_i 
  month = Date::MONTHNAMES[data[:month].to_i]
  dept = DEPT[data[:department].to_i]

  key = data[:key].to_i
  number = ssn[0..12].to_i
  expected_key = 97 - (number % 97)

  if key == expected_key
    puts "A #{gender}, born in #{month}, 19#{year} in #{dept}"
  else
    puts "Invalid key number"
  end

end

puts ssn_info("186037510803191")
puts ssn_info("286107511451175")
puts ssn_info("1 84 12 76 451 089 46")