AoCDay07.kt

import kotlin.math.pow

fun main(args: Array<String>) {
    println(solveDay07Part1("07.txt"))
    println(solveDay07Part2("07.txt"))
}

val DECK_OF_CARDS = setOf(
    '2', '3', '4', '5', '6', '7', '8', '9', 'T', 'J', 'Q', 'K', 'A'
)

fun solveDay07Part1(filename: String): Long {
    var sum = 0L
    val lines = FileUtils.readFromClasspath(filename)
    val bids = lines.map { it.split(" ") }
        .map { Bid(it[0].trim(), it[1].trim().toInt()) }
    var sorted = bids.sorted()
    for ((i, bid) in sorted.withIndex()) {
        sum += (i + 1) * bid.amount
    }
    return sum
}

fun solveDay07Part2(filename: String): Int {
    val lines = FileUtils.readFromClasspath(filename)

    //TODO: Implement
    return -1
}

data class Bid(val cards: String, val amount: Int) : Comparable<Bid> {


    fun cardValueByPosition(): Long {
        var sum = 0L
        for ((i, c) in cards.withIndex()) {
//            println("Value of $c is ${DECK_OF_CARDS.indexOf(c)}")
            val value = 10.toDouble().pow(cards.length - i - 1) * (DECK_OF_CARDS.indexOf(c) + 2)
//            println(value)
            sum += value.toLong()
        }
        return sum

    }

    fun detectHand(): Hands {
        val groupedCards = cards.toCharArray()
            .groupBy { DECK_OF_CARDS.indexOf(it) }
        val hand = when {
            groupedCards.size == 1 ->
                Hands.FIVE_OF_A_KIND

            groupedCards.any { it.value.size == 4 } ->
                Hands.FOUR_OF_A_KIND

            groupedCards.size == 2 ->
                Hands.FULL_HOSE

            groupedCards.any { it.value.size == 3 } ->
                Hands.THREE_OF_A_KIND

            groupedCards.filter { it.value.size == 2 }.count() == 2 ->
                Hands.TWO_PAIRS

            groupedCards.any { it.value.size == 2 } ->
                Hands.PAIR

            else ->
                Hands.HIGH_CARD

        }
        return hand;

    }

    override fun compareTo(other: Bid): Int {
        return compareBy<Bid>({ it.detectHand() }, { it.cardValueByPosition() }).compare(this, other)
    }

}

enum class Hands {
    HIGH_CARD, PAIR, TWO_PAIRS, THREE_OF_A_KIND, FULL_HOSE, FOUR_OF_A_KIND, FIVE_OF_A_KIND
}