A chat sanitiser exercise to get familiar with Kotlin

ChatSanitiser.kt

data class BadWord(val word:String, val severity:Int)

fun main(args: Array<String>) {

    val chat = Chat()

    while(true){
        println("Enter message...")

        val input = readLine()
        if(input == "!q") System.exit(0)

        chat.printWithWarning(input!!)
    }
}

class Chat:Sanitiser {
    override val badWords: Set<BadWord> =
            setOf ( BadWord("hi", 2),   BadWord("hello", 4),
                    BadWord("star", 1), BadWord("wars", 6),
                    BadWord("work",9),  BadWord("iron",4))

    fun printWithWarning(s:String){
        val score = sanitiseScore(s, Level1Validation(), Level2Validation())

        when(score) {
            0       -> println(s)
            in 1..4 -> println("Warning($score): Watch your language: $s")
            in 4..7 -> println("Warning($score): Alerting moderator: $s")
            else -> println("Action($score): Ban hammer!: $s")
        }
    }
}

interface Sanitiser {

    val badWords:Set<BadWord>

    fun Level1Validation() : (s:String) -> Int = { s ->
        badWords.intersect(s.split(" ")).size
    }

    fun Level2Validation() : (s: String) -> Int = { s ->
        val words = s.split(" ")
        badWords.fold(0) { total, bw -> if (words.contains(bw.word)) total + bw.severity else total }
    }

    fun sanitiseScore(s: String, vararg sanitisers: (String) -> (Int)) =
            sanitisers.fold(0) { total, f -> total + f(s) } / sanitisers.size
}