blokus.scala

case class Point(x: Int, y: Int) {
  require(x >= 0)
  require(y >= 0)
}

case class Piece(ps: Set[Point]) {
  def flip = {
    val mx = spanx
    Piece(ps.map(p => Point(mx - p.x, p.y)))
  }
  
  def rotate = {
    val my = spany
    Piece(ps.map(p => Point(my - p.y, p.x)))
  }
  
  def permute = {
    import scala.collection.mutable.{Set => MutableSet}
    
    def loop(acc: MutableSet[Piece], p: Piece) {
      if (!acc.contains(p))
        loop(acc += p, p.rotate)
    }
    
    val acc = MutableSet[Piece]()
    loop(acc, this)
    loop(acc, this.flip)
    acc.toSet
  }
  
  def spanx = ps.map(_.x).max
  def spany = ps.map(_.y).max
  
  def dump {
    val chrs = Map(true -> "*", false -> " ")
    val mx = spanx
    val my = spany
    
    for (y <- 0 to my) {
      val xs = ps.filter(_.y == y).map(_.x)
      println("[" + (0 to mx).map(x => chrs(xs(x))).mkString + "]")
    }
    println
  }
}

object Piece {
  def fromCoords(coords: (Int, Int)*) =
    Piece(coords.map(t => Point(t._1, t._2)).toSet)
  
  def all = List(
    
    // 1
    Piece.fromCoords((0, 0)),
    
    // 2
    Piece.fromCoords((0, 0), (0, 1)),
    
    // 3
    Piece.fromCoords((0, 0), (0, 1), (0, 2)),
    Piece.fromCoords((0, 0), (0, 1), (1, 1)),
    
    // 4
    Piece.fromCoords((0, 0), (0, 1), (0, 2), (0, 3)),
    Piece.fromCoords((0, 2), (1, 0), (1, 1), (1, 2)),
    Piece.fromCoords((0, 0), (0, 1), (0, 2), (1, 1)),
    Piece.fromCoords((0, 0), (0, 1), (1, 0), (1, 1)),
    Piece.fromCoords((0, 0), (1, 0), (1, 1), (2, 1)),
    
    // 5
    Piece.fromCoords((0, 0), (0, 1), (0, 2), (0, 3), (0, 4)),
    Piece.fromCoords((0, 3), (1, 0), (1, 1), (1, 2), (1, 3)),
    Piece.fromCoords((0, 2), (0, 3), (1, 0), (1, 1), (1, 2)),
    Piece.fromCoords((0, 1), (0, 2), (1, 0), (1, 1), (1, 2)),
    Piece.fromCoords((0, 0), (0, 2), (1, 0), (1, 1), (1, 2)),
    Piece.fromCoords((0, 0), (0, 1), (0, 2), (0, 3), (1, 1)),
    Piece.fromCoords((0, 2), (1, 0), (1, 1), (1, 2), (2, 2)),
    Piece.fromCoords((0, 0), (0, 1), (0, 2), (1, 2), (2, 2)),
    Piece.fromCoords((0, 0), (1, 0), (1, 1), (2, 1), (2, 2)),
    Piece.fromCoords((0, 0), (0, 1), (1, 1), (2, 1), (2, 2)),
    Piece.fromCoords((0, 0), (0, 1), (1, 1), (2, 1), (1, 2)),
    Piece.fromCoords((0, 1), (1, 0), (1, 1), (1, 2), (2, 1))
    
  )
}