From a516f8e784764cb68b6c5aeb99d20deda006adb1 Mon Sep 17 00:00:00 2001
From: Denis Simon <denis.v.simon@gmail.com>
Date: Tue, 8 Jan 2019 21:35:15 +0300
Subject: [PATCH] Swift implementation

---
 README.md                 |  1 +
 Swift/XOREncryption.swift | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+)
 create mode 100644 Swift/XOREncryption.swift

diff --git a/README.md b/README.md
index 12f88cd..9fa85bf 100644
--- a/README.md
+++ b/README.md
@@ -16,6 +16,7 @@ Simple implementation of XOR Encryption/Decrypting in various languages, includi
 - [Objective-C](Objective-C/main.m)
 - [Python](Python/XOREncryption.py)
 - [Ruby](Ruby/xor.rb)
+- [Swift](Swift/XOREncryption.swift)
 - [Visual Basic.NET](VB.NET/XORCrypto.vb)
 
 This implementation goes beyond the basic single-key model to use multiple keys in a particular sequence, making it that much more difficult to brute-force.
diff --git a/Swift/XOREncryption.swift b/Swift/XOREncryption.swift
new file mode 100644
index 0000000..a04680d
--- /dev/null
+++ b/Swift/XOREncryption.swift
@@ -0,0 +1,33 @@
+//
+//  XOREncryption.swift
+//  XOREncryption
+//
+//  Created by Denis Simon on 2019-01-08.
+//
+
+import Foundation
+
+extension Character {
+    func utf8() -> UInt8 {
+        let utf8 = String(self).utf8
+        return utf8[utf8.startIndex]
+    }
+}
+
+func encryptDecrypt(_ input: String) -> String {
+    let key = "KCQ".characters.map { $0 } //Can be any chars, and any length array
+    let length = key.count
+    var output = ""
+    
+    for i in input.characters.enumerated() {
+        let byte = [i.element.utf8() ^ key[i.offset % length].utf8()]
+        output.append(String(bytes: byte, encoding: .utf8)!)
+    }
+    
+    return output
+}
+
+let encrypted = encryptDecrypt("Hello, World!")
+print("Encrypted: \(encrypted)") // output: Encrypted: &=',}k>9/5j
+let decrypted = encryptDecrypt(encrypted)
+print("Decrypted: \(decrypted)") // output: Decrypted: Hello, World!