From e6fa01c77ceb8a600521da8c32dd4e1075ae0527 Mon Sep 17 00:00:00 2001
From: Alessandro Berardi <berardialessandro@gmail.com>
Date: Wed, 21 Dec 2016 11:29:02 +1030
Subject: [PATCH] WIP

---
 .../types/credit_card.rb                      | 25 +++------
 .../types/credit_card_spec.rb                 | 53 ++-----------------
 2 files changed, 11 insertions(+), 67 deletions(-)

diff --git a/lib/sensitive_data_filter/types/credit_card.rb b/lib/sensitive_data_filter/types/credit_card.rb
index c65fdcb..adc3136 100644
--- a/lib/sensitive_data_filter/types/credit_card.rb
+++ b/lib/sensitive_data_filter/types/credit_card.rb
@@ -4,21 +4,11 @@
 module SensitiveDataFilter
   module Types
     module CreditCard
-      SEPARATORS      = /[\s-]/
-      SEPRS           = SEPARATORS.source + '+'
-      CARD_16_DIGITS  = /\d{4}#{SEPRS}\d{4}#{SEPRS}\d{4}#{SEPRS}\d{4}/
-      CARD_13_DIGITS  = /\d{3}#{SEPRS}\d{3}#{SEPRS}\d{3}#{SEPRS}\d#{SEPRS}\d{3}/
-      CARD_14_DIGITS  = /\d{4}#{SEPRS}\d{6}#{SEPRS}\d{4}/
-      CARD_15_DIGITS  = /\d{4}#{SEPRS}\d{6}#{SEPRS}\d{5}/
-      CARD            = /
-                            #{CARD_16_DIGITS.source}
-                          | #{CARD_13_DIGITS.source}
-                          | #{CARD_14_DIGITS.source}
-                          | #{CARD_15_DIGITS.source}
-                        /x
-      CATCH_ALL_SEPRS = SEPARATORS.source + '*'
-      CATCH_ALL       = /(?:\d#{CATCH_ALL_SEPRS}?){13,16}/
-      FILTERED        = '[FILTERED]'
+      SEPARATORS = /[\s-]/
+      SEPRS      = SEPARATORS.source + '*'
+      LENGTHS    = (11..19)
+      CARD       = Regexp.new(LENGTHS.map { |l| /(?=((?:\d#{SEPRS}){#{l-1}}\d))/.source }.join)
+      FILTERED   = '[FILTERED]'
 
       module_function def valid?(number)
         return false unless number.is_a? String
@@ -27,9 +17,8 @@ module CreditCard
 
       module_function def scan(value)
         return [] unless value.is_a? String
-        [CARD, CATCH_ALL]
-          .flat_map { |pattern| value.scan(pattern) }.uniq
-          .select { |card| valid?(card) }
+        puts "SCAN #{value.scan(CARD)}"
+        value.scan(CARD).flatten.select { |card| valid?(card) }
       end
 
       module_function def mask(value)
diff --git a/spec/sensitive_data_filter/types/credit_card_spec.rb b/spec/sensitive_data_filter/types/credit_card_spec.rb
index 917abab..0c869c4 100644
--- a/spec/sensitive_data_filter/types/credit_card_spec.rb
+++ b/spec/sensitive_data_filter/types/credit_card_spec.rb
@@ -68,7 +68,7 @@ def validations(cards)
 
     context 'a value that contains repeated valid credit card numbers' do
       let(:value) { 'cc1 4111 1111 1111 1111 cc2 4111 1111 1111 1111 123' }
-      specify { expect(scan).to eq ['4111 1111 1111 1111'] }
+      specify { expect(scan).to eq ['4111 1111 1111 1111', '4111 1111 1111 1111'] }
     end
 
     context 'a value that contains a valid credit card in a multi line string' do
@@ -107,54 +107,9 @@ def validations(cards)
       specify { expect(mask).to eq value }
     end
 
-    context 'a value that is a luhn but not a credit card' do
-      let(:value) { '1234-5678-9012-3528' }
-      specify { expect(scan).to be_empty }
-      specify { expect(mask).to eq value }
-    end
-  end
-
-  describe 'pattern matching' do
-    shared_examples_for 'a pattern matcher' do
-      context 'valid pattern' do
-        it 'should match' do
-          expect(subject.match(valid_match)[0]).to eq valid_match
-        end
-      end
-
-      context 'invalid pattern' do
-        it 'should not match' do
-          expect(subject.match(invalid_match)).to be_nil
-        end
-      end
-    end
-
-    context '13 digit card pattern' do
-      subject { SensitiveDataFilter::Types::CreditCard::CARD_13_DIGITS }
-      let(:valid_match) { '123-123-123-1-123' }
-      let(:invalid_match) { '1234-123-123-1-35' }
-      it_behaves_like 'a pattern matcher'
-    end
-
-    context '14 digit card pattern' do
-      subject { SensitiveDataFilter::Types::CreditCard::CARD_14_DIGITS }
-      let(:valid_match) { '1234-123456-1234' }
-      let(:invalid_match) { '1234-12345-123' }
-      it_behaves_like 'a pattern matcher'
-    end
-
-    context '15 digit card' do
-      subject { SensitiveDataFilter::Types::CreditCard::CARD_15_DIGITS }
-      let(:valid_match) { '1234-123456-12345' }
-      let(:invalid_match) { '123-1234567-12345' }
-      it_behaves_like 'a pattern matcher'
-    end
-
-    context '16 digit card pattern' do
-      subject(:card_16_digits) { SensitiveDataFilter::Types::CreditCard::CARD_16_DIGITS }
-      let(:valid_match) { '1234-5678-9012-3528' }
-      let(:invalid_match) { '1234-15678-012-3528' }
-      it_behaves_like 'a pattern matcher'
+    context 'the scan' do
+      let(:value) { '1234111 1111 1111 1111234' }
+      specify { expect(scan).to eq ['4111 1111 1111 1111'] }
     end
   end
 end