Merge pull request #30 from cblanc/bring_back_verify

Bring back verify

lib/verification.rb

@@ -1,4 +1,45 @@
 module Verification
+	def Verification.verify input
+		md5 = Digest::MD5.hexdigest("9WvcZ9hX" + input + "KF7L4luQ").upcase.split(//)
+		chars = ["A", "B", "C", "D", "E", "F"]
+		nums = []
+		lastPos = md5[31].to_i
+		result = ""
+
+		for i in 0..9
+			pos = md5[i].to_i
+
+			if pos == 0
+				pos = lastPos ** (i % 4)
+			elsif (pos % 4) == 0
+				pos = pos * lastPos + i
+			elsif (pos % 3) == 0
+				pos = pos ** (i % 4)
+			elsif (pos % 2) == 0
+				pos = pos * i + pos
+			end
+
+			pos = (pos > 31) ? (pos % 32) : pos
+			curChar = md5[31 - pos]
+			curNum = curChar.to_i
+
+			if nums.include? curNum
+				if curNum == 0
+					curChar = chars[pos % 6]
+				else
+					curChar = (pos % 10).to_s
+				end
+				curNum = curChar.to_i
+			end
+
+			nums << curNum
+			result << curChar
+			lastPos = pos
+		end
+
+		return result
+	end
+
 	def Verification.uncrap str
 		str.to_s.gsub(/[^A-Za-z0-9_\-]/, "")
 	end