Roman Tsaruk

META-INF/MANIFEST.MF

@@ -0,0 +1,3 @@
+Manifest-Version: 1.0
+Main-Class: ua.com.javarush.gnew.Main
+

inputData.txt

@@ -0,0 +1,15 @@
+The sun was setting over the quiet village,
+casting a warm golden glow on the cobblestone streets.
+Birds chirped softly, preparing for the night as the first stars appeared in the sky.
+People were slowly closing their shops, exchanging friendly smiles and goodbyes.
+ Children played in the park, their laughter echoing through the air. In the distance,
+ the gentle sound of a river flowing added to the serene atmosphere.
+A couple walked hand in hand, enjoying the cool evening breeze.
+Life in the village was peaceful, with a comforting sense of community that made everyone feel at home.
+In a quiet village nestled between rolling hills and dense forests, life moved at a gentle pace.
+Every morning, the sun would rise slowly over the horizon, casting a warm golden glow across the fields.
+The villagers, friendly and hardworking, went about their daily routines with a sense of contentment.
+Children played near the stream, their laughter echoing through the trees.
+Elderly folks shared stories of olden days on the benches under the large oak tree.
+As evening approached, the village would gather around the bonfire, enjoying the simple pleasures of life,
+and the stars would shine brightly in the clear night sky.

readme.md

@@ -1,3 +1,9 @@
+Вдалося реалізувати базові умови до проекту.
+В наступному релізі планую реалізувати ще додаткові завдання.
+Домашні завдання після лекцій було легко виконувати, а вот поєднати весь пройдений матеріал в одному проекті вже складніше.
+Приходилось трішки гуглити бо пройдений матеріал забувається без постійної практики.
+В подальшому з набуттям нових знань думаю перепишу проект і зроблю його набагото досконалішим).
+
 
 ## Run the program
 
@@ -25,4 +31,4 @@
 ### Argument could be in any order
 ```
 -e -f "/path/to/file.txt" -k 1
-```
+```

src/main/java/ua/com/javarush/gnew/Main.java

@@ -2,28 +2,36 @@
 
 import ua.com.javarush.gnew.crypto.Cypher;
 import ua.com.javarush.gnew.file.FileManager;
+import ua.com.javarush.gnew.file.PathManager;
 import ua.com.javarush.gnew.runner.ArgumentsParser;
 import ua.com.javarush.gnew.runner.Command;
 import ua.com.javarush.gnew.runner.RunOptions;
 
-import java.nio.file.Path;
 
 public class Main {
+    //start a project
     public static void main(String[] args) {
         Cypher cypher = new Cypher();
         FileManager fileManager = new FileManager();
         ArgumentsParser argumentsParser = new ArgumentsParser();
         RunOptions runOptions = argumentsParser.parse(args);
+        PathManager pathManager = new PathManager();
 
         try {
             if (runOptions.getCommand() == Command.ENCRYPT) {
                 String content = fileManager.read(runOptions.getFilePath());
                 String encryptedContent = cypher.encrypt(content, runOptions.getKey());
-                String fileName = runOptions.getFilePath().getFileName().toString();
-                String newFileName = fileName.substring(0, fileName.length() - 4) + " [ENCRYPTED].txt";
-
-                Path newFilePath = runOptions.getFilePath().resolveSibling(newFileName);
-                fileManager.write(newFilePath, encryptedContent);
+                fileManager.write(pathManager.newFilePath(runOptions), encryptedContent);
+            }
+            if (runOptions.getCommand() == Command.DECRYPT) {
+                String content = fileManager.read(runOptions.getFilePath());
+                String decryptedContent = cypher.decrypt(content, runOptions.getKey());
+                fileManager.write(pathManager.newFilePath(runOptions), decryptedContent);
+            }
+            if (runOptions.getCommand() == Command.BRUTEFORCE) {
+                String content = fileManager.read(runOptions.getFilePath());
+                String bruteForceContent = cypher.bruteForce(content);
+                fileManager.write(pathManager.newFilePath(runOptions), bruteForceContent);
             }
         } catch (Exception e) {
             System.out.println(e.getMessage());

src/main/java/ua/com/javarush/gnew/crypto/Cypher.java

@@ -1,15 +1,14 @@
 package ua.com.javarush.gnew.crypto;
 
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Collections;
+import java.util.*;
 
 public class Cypher {
+    public static int key;
     private final ArrayList<Character> originalAlphabet = new ArrayList<>(Arrays.asList('A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'));
 
 
     public String encrypt(String input, int key) {
-        key = Math.negateExact(key);
+        key = -key;
 
         ArrayList<Character> rotatedAlphabet = new ArrayList<>(originalAlphabet);
         Collections.rotate(rotatedAlphabet, key);
@@ -22,6 +21,46 @@ public String encrypt(String input, int key) {
         return builder.toString();
     }
 
+    public String decrypt(String input, int key) {
+        return encrypt(input, -key);
+    }
+
+    public String bruteForce(String input) {
+        int maxCount = 0;
+        int key = 0;
+        String bestOutput ="";
+        HashSet<String> engWords = new HashSet<>(List.of("are", "not", "am", "get", "do", "the", "be", "and", "to", "of", "have", "you", "at", "for", "was"));
+
+
+        for (int i = 1; i <= 25; i++) {
+            ArrayList<Character> rotatedAlphabet = new ArrayList<>(originalAlphabet);
+            Collections.rotate(rotatedAlphabet, i);
+            char[] charArray = input.toCharArray();
+
+            StringBuilder builder = new StringBuilder();
+            for (char symbol : charArray) {
+                builder.append(processSymbol(symbol, rotatedAlphabet));
+            }
+            String output = builder.toString();
+
+            int count = 0;
+            String[] words = output.split("\\s+");
+            for (String word : words) {
+                if (engWords.contains(word.toLowerCase())) {
+                    count++;
+                }
+            }
+
+            if (count > maxCount) {
+                maxCount = count;
+                key = i;
+                bestOutput = output;
+            }
+        }
+        Cypher.key = key;
+        return bestOutput;
+    }
+
     private Character processSymbol(char symbol, ArrayList<Character> rotatedAlphabet) {
         if (!originalAlphabet.contains(symbol)) {
             return symbol;

src/main/java/ua/com/javarush/gnew/file/FileManager.java

@@ -1,15 +1,26 @@
 package ua.com.javarush.gnew.file;
 
+import ua.com.javarush.gnew.runner.RunOptions;
+
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
 
 public class FileManager {
-    public String read(Path filePath) throws IOException {
-        return Files.readString(filePath);
+
+    public String read(Path filePath) {
+        try {
+            return Files.readString(filePath);
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
     }
 
-    public void write(Path filePath, String content) throws IOException {
-        Files.writeString(filePath, content);
+    public void write(Path filePath, String content) {
+        try {
+            Files.writeString(filePath, content);
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
     }
 }

src/main/java/ua/com/javarush/gnew/file/PathManager.java

@@ -0,0 +1,26 @@
+package ua.com.javarush.gnew.file;
+
+import ua.com.javarush.gnew.crypto.Cypher;
+import ua.com.javarush.gnew.runner.RunOptions;
+
+import java.nio.file.Path;
+
+public class PathManager {
+    public Path newFilePath(RunOptions runOptions) {
+        String label = switch (runOptions.getCommand()) {
+            case ENCRYPT -> " [ENCRYPTED]";
+            case DECRYPT -> " [DECRYPTED]";
+            case BRUTEFORCE -> " [BRUTEFORCE]";
+            default -> null;
+        };
+
+        String fileName = runOptions.getFilePath().getFileName().toString();
+        StringBuilder newFileName = new StringBuilder(fileName.substring(0, fileName.length() - 4));
+        newFileName.append(label);
+        if (label.equals(" [BRUTEFORCE]")) {
+            newFileName.append(" key ").append(Cypher.key);
+        }
+        newFileName.append(".txt");
+        return runOptions.getFilePath().resolveSibling(newFileName.toString());
+    }
+}

src/main/java/ua/com/javarush/gnew/runner/ArgumentsParser.java

@@ -48,7 +48,7 @@ public RunOptions parse(String[] args) {
             throw new IllegalArgumentException("Command (-e, -d, or -bf) is required");
         }
 
-        if (key == null) {
+        if (key == null && command!=Command.BRUTEFORCE) {
             throw new IllegalArgumentException("Key is required for encrypt or decrypt mode");
         }