Fix the key parsing in the gamma actions.

src/cipher_analytical_machine/ciphers/gamma.clj

@@ -65,3 +65,14 @@
          (map vector array)
          (map (fn [[a g]] (add-mod a g module))))))
 
+(defn decrypt-message
+  "Decrypt a message using the gamma cipher. The function is case-insensitive. The key is an array of three elements [a b c]. The array contains integer in range [0, module)."
+  [key symbols message]
+  (let [module (count symbols)
+        table (ss/generate-sorted-substitution-table symbols)]
+    (->> message
+         (ss/decrypt-by-table (set/map-invert table))
+         (decrypt-array key module)
+         (ss/decrypt-by-table table)
+         (cs/join))))
+

src/cipher_analytical_machine/cli/actions/cryptography.clj

@@ -1,7 +1,9 @@
 (ns cipher-analytical-machine.cli.actions.cryptography
   (:require
+   [clojure.string :as cs]
    [cipher-analytical-machine.ciphers.caesar :as caesar]
    [cipher-analytical-machine.ciphers.simple-substitution :as ss]
+   [cipher-analytical-machine.ciphers.gamma :as gamma]
    [cipher-analytical-machine.parsers.parsers :as ps]
    [cipher-analytical-machine.parsers.simple-substitution :as pss])
   (:gen-class))
@@ -38,6 +40,20 @@
             substitution-table (get data "table")]
         (ss/decrypt-message-with-caesar message key substitution-table symbols)))))
 
+(defn gamma-actions
+  [options arguments action-type]
+  (let [message (:message options)
+        key (->> (cs/split (:key options) #",")
+                 (map #(Integer/parseInt %))
+                 (into []))
+        symbols (:symbols options)]
+    (cond
+      (= action-type :encrypt)
+      (gamma/encrypt-message key symbols message)
+
+      (= action-type :decrypt)
+      (gamma/decrypt-message key symbols message))))
+
 (defn cryptography-actions
   [options arguments action-type]
   (let [cipher (:cipher options)]
@@ -46,5 +62,8 @@
       (caesar-actions options arguments action-type)
 
       (= cipher "Simple substitution and Caesar")
-      (simple-substitution-with-caesar-actions options arguments action-type))))
+      (simple-substitution-with-caesar-actions options arguments action-type)
+
+      (= cipher "Gamma")
+      (gamma-actions options arguments action-type))))
 

test/cipher_analytical_machine/ciphers/gamma_test.clj

@@ -53,3 +53,10 @@
       [4 32 15] 33 [6 28 2 8 3 5 13 16 21 1] [3 14 1 4 18 19 23 8 27 17]
       [1 2  3 ] 3  [0 1 2 2 0 2 1 1 0]       [0 2 1 1 0 1 2 2 0])))
 
+(deftest decrypt-message-test
+  (testing "Checking that the message is decrypted as expected"
+    (are [key symbols message expected]
+        (= expected (decrypt-message key symbols message))
+      [4 32 15] "абвгґдеєжзиіїйклмнопрстуфхцчшщьюя" "ешвжгдймсб" "гкбґопужчн"
+      [1 2  3 ] "абв" "абввавбба" "авббабвва")))
+