package be.vandewalleh.aoc.days

import be.vandewalleh.aoc.utils.input.Day
import be.vandewalleh.aoc.utils.input.Text

private typealias Entry = Pair<String, String>
private typealias Entries = List<Entry>

@Day(4)
class Day04(@Text val input: String) {

    val entries = input.split("\n\n").map {
        it.split(" ", "\n").map { it.split(":").let { (k, v) -> k to v } }
    }

    private fun Entries.hasRequiredKeys() = map { it.first }
        .containsAll(listOf("byr", "iyr", "eyr", "hgt", "hcl", "ecl", "pid"))

    fun part1() = entries.count { it.hasRequiredKeys() }

    private val hclRegex = Regex("#[0-9a-f]{6}")
    private val pidRegex = Regex("[0-9]{9}")

    private fun Entry.isValid() = let { (k, v) ->
        when (k) {
            "byr" -> v.toInt() in 1920..2002
            "iyr" -> v.toInt() in 2010..2020
            "eyr" -> v.toInt() in 2020..2030
            "hgt" -> when {
                v.endsWith("cm") -> v.removeSuffix("cm").toInt() in 150..193
                v.endsWith("in") -> v.removeSuffix("in").toInt() in 59..76
                else -> false
            }
            "hcl" -> v.matches(hclRegex)
            "ecl" -> v in arrayOf("amb", "blu", "brn", "gry", "grn", "hzl", "oth")
            "pid" -> v.matches(pidRegex)
            else -> true
        }
    }

    fun part2() = entries.count { it.hasRequiredKeys() && it.all { it.isValid() } }
}