Advent of Code 04 part 2.scala

import java.io.FileInputStream
import scala.io.StdIn

@main def solve4() =
  val validKeys: Set[String] = Set("byr", "iyr", "eyr", "hgt", "hcl", "ecl", "pid") 
  def isValid(passport: Vector[(String, String)]): Boolean = {
    val keys = passport.map { _._1 }.toSet
    val elemnts = passport.toMap

    def checkRangedNumber(min: Int, max: Int, value: String): Boolean = {
      value.nonEmpty && value.forall(_.isDigit) && min <= value.toInt && max >= value.toInt
    }
    def hasAllKeys: Boolean = {
      (validKeys diff keys).isEmpty
    }
    def checkByr: Boolean = checkRangedNumber(1920, 2002, elemnts.getOrElse("byr", ""))
    def checkIyr: Boolean = checkRangedNumber(2010, 2020, elemnts.getOrElse("iyr", ""))
    def checkEyr: Boolean = checkRangedNumber(2020, 2030, elemnts.getOrElse("eyr", ""))
    def checkHgt: Boolean = {
      val hgt = elemnts.getOrElse("hgt", "")
      if hgt.endsWith("cm") then
        checkRangedNumber(150, 193, hgt.substring(0, hgt.size - 2))
      else if hgt.endsWith("in") then
        checkRangedNumber(59, 76, hgt.substring(0, hgt.size - 2))
      else
        false
    }
    def checkHcl: Boolean = {
      val hcl = elemnts.getOrElse("hcl", "")
      hcl.size == 7 && hcl(0) == '#' && hcl.tail.forall(c => c.isDigit || ('a' <= c && c <= 'f'))
    }
    def checkEcl: Boolean = {
      val validElements = Set("amb", "blu", "brn", "gry", "grn", "hzl", "oth")
      validElements.contains(elemnts.getOrElse("ecl", ""))
    }
    def checkPid: Boolean = {
      val pid = elemnts.getOrElse("pid", "")
      pid.size == 9 && pid.forall(_.isDigit)
    }
    
    val validators = Vector(
      hasAllKeys,
      checkByr,
      checkIyr,
      checkEyr,
      checkHgt,
      checkHcl,
      checkEcl,
      checkPid,
    )
    validators.forall(_ == true)
  }

  val in = new FileInputStream("example4-1.in")
  System.setIn(in)

  val inputs = Iterator.continually(StdIn.readLine()).takeWhile(_ != null).toVector
  val passportElements = inputs.foldLeft(Vector[Vector[(String, String)]](Vector())) { (acc, line) =>
    if line.trim.isEmpty then
      acc :+ Vector()
    else
      acc.init :+ (acc.last ++ line.split(" ").map { x => 
        val Array(key, value) = x.split(":")
        (key, value)
      }.toVector) 
  }
  println(passportElements.count(isValid))