From 6a74c38707eb109c936ad5254cfd3fbaab2ff6bd Mon Sep 17 00:00:00 2001
From: Snow Helsing <snow.helsing@gmail.com>
Date: Thu, 16 Jun 2016 01:36:33 +0800
Subject: [PATCH] FIX: support utf-8 string

---
 lib/rc4.rb | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/lib/rc4.rb b/lib/rc4.rb
index cbcd2d8..534d5e7 100644
--- a/lib/rc4.rb
+++ b/lib/rc4.rb
@@ -8,15 +8,12 @@ def initialize(str)
   end
 
   def encrypt!(text)
-    index = 0
-    while index < text.length
+    text.force_encoding('utf-8').unpack('U*').map do |code|
       @q1 = (@q1 + 1) % 256
       @q2 = (@q2 + @state[@q1]) % 256
       @state[@q1], @state[@q2] = @state[@q2], @state[@q1]
-      text.setbyte(index, text.getbyte(index) ^ @state[(@state[@q1] + @state[@q2]) % 256])
-      index += 1
-    end
-    text
+      code ^ @state[(@state[@q1] + @state[@q2]) % 256]
+    end.pack 'U*'
   end
 
   alias_method :decrypt!, :encrypt!