Scala base64 encryption with alternative encodings

b64.scala

val b64_ZH = "的一是不了人我在有他这中大来上国个到说们为子和你地出道也时年得" +
			 "就那要下以生会自着去之过家学对可她里后小么心多天而能好都然没日。"
val b64_EN = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
val input = "Man is distinguished, not only by his reason, but by this singular " +
            "passion from other animals, which is a lust of the mind, that by a " + 
            "perseverance of delight in the continued and indefatigable generation " +
            "of knowledge, exceeds the short vehemence of any carnal pleasure."

def strToAscii(s: String) : List[Int] = {
	val ascii = for {
		c <- s
	} yield c.toInt

	ascii.toList
}

def asciiToBinary(ascii: List[Int]) = {
	val binaryList = for {
		n <- ascii
	} yield ("%8s" format (Integer.toBinaryString(n))).replace(' ','0')
	binaryList.reduceLeft((a,b) => a + b)
}

def binaryToNumbers(binary: String) : List[Int] = {
	def peel(s: String, acc: List[Int]) : List[Int] = {
		if(s.length >= 6) {
			peel(s drop 6, acc :+ Integer.parseInt(s take 6,2))
		} else if(s=="") {
			acc
		} else {
			//Pad the string to get a six-character string
			acc :+ Integer.parseInt(s + ("0" * (6 - s.length)),2)
		}
	}

	peel(binary,List())
}

def numbersToB64(nums: List[Int], b64map: String) : String = {
	(nums map (n => b64map(n))).mkString
}

val t = strToAscii(input)
val bin = asciiToBinary(t)
val nums = binaryToNumbers(bin)
println(numbersToB64(nums,b64_ZH))