base.rb in sec_id-1.1.0

- old
+ new

@@ -1,11 +1,31 @@
 # frozen_string_literal: true
 
 module SecId
   class Base
-    LETTERS = Set.new('A'..'Z').freeze
+    CHAR_TO_DIGITS = {
+      '0' => 0,      '1' => 1,      '2' => 2,      '3' => 3,      '4' => 4,
+      '5' => 5,      '6' => 6,      '7' => 7,      '8' => 8,      '9' => 9,
+      'A' => [1, 0], 'B' => [1, 1], 'C' => [1, 2], 'D' => [1, 3], 'E' => [1, 4],
+      'F' => [1, 5], 'G' => [1, 6], 'H' => [1, 7], 'I' => [1, 8], 'J' => [1, 9],
+      'K' => [2, 0], 'L' => [2, 1], 'M' => [2, 2], 'N' => [2, 3], 'O' => [2, 4],
+      'P' => [2, 5], 'Q' => [2, 6], 'R' => [2, 7], 'S' => [2, 8], 'T' => [2, 9],
+      'U' => [3, 0], 'V' => [3, 1], 'W' => [3, 2], 'X' => [3, 3], 'Y' => [3, 4], 'Z' => [3, 5],
+      '*' => [3, 6], '@' => [3, 7], '#' => [3, 8]
+    }.freeze
 
+    CHAR_TO_DIGIT = {
+      '0' => 0,  '1' => 1,  '2' => 2,  '3' => 3,  '4' =>  4,
+      '5' => 5,  '6' => 6,  '7' => 7,  '8' => 8,  '9' =>  9,
+      'A' => 10, 'B' => 11, 'C' => 12, 'D' => 13, 'E' => 14,
+      'F' => 15, 'G' => 16, 'H' => 17, 'I' => 18, 'J' => 19,
+      'K' => 20, 'L' => 21, 'M' => 22, 'N' => 23, 'O' => 24,
+      'P' => 25, 'Q' => 26, 'R' => 27, 'S' => 28, 'T' => 29,
+      'U' => 30, 'V' => 31, 'W' => 32, 'X' => 33, 'Y' => 34, 'Z' => 35,
+      '*' => 36, '@' => 37, '#' => 38
+    }.freeze
+
     attr_reader :identifier, :check_digit
 
     def self.valid?(id)
       new(id).valid?
     end
@@ -48,17 +68,18 @@
     alias to_str to_s
 
     private
 
     def digitized_identifier
-      @digitized_identifier ||= identifier.each_char.flat_map { |char| char_to_digits char }
+      raise NotImplementedError
     end
 
     def char_to_digits(char)
-      return char.to_i unless LETTERS.include? char
+      CHAR_TO_DIGITS.fetch(char)
+    end
 
-      number = char.to_i(36)
-      [number / 10, number % 10]
+    def char_to_digit(char)
+      CHAR_TO_DIGIT.fetch(char)
     end
 
     def mod_10(sum)
       (10 - (sum % 10)) % 10
     end