GameOfLife TypeDD and Sequence test

gameoflife.kt

package mtpcraft.tdd.kata

import kotlin.random.Random

sealed class Cell {
    companion object
}

object Dead : Cell()
object Living : Cell()

sealed class Neighbors {
    object Two : Neighbors()
    object Three : Neighbors()
    object LessThanTwo : Neighbors()
    object MoreTHanThree : Neighbors()
}

data class GridCell(val living: Cell, val x: Int, val y: Int)

typealias Grid = Sequence<GridCell>

typealias AnalyzableCells = Pair<Cell, Neighbors>

fun evolve(analyzableCell: AnalyzableCells): Cell = analyzableCell.let { (focus, neighbours) ->
    when (neighbours) {
        Neighbors.Three -> Living
        Neighbors.Two -> focus
        Neighbors.LessThanTwo -> Dead
        Neighbors.MoreTHanThree -> Dead
    }
}

fun isAdjacent(focus: GridCell, other: GridCell): Boolean =
    other.x in focus.x - 1..focus.x + 1 &&
            other.y in focus.y - 1..focus.y + 1

fun neighbors(cells: Sequence<Cell>): Neighbors =
    when (cells.filter { it is Living }.toList().size) {
        in 0..1 -> Neighbors.LessThanTwo
        2 -> Neighbors.Two
        3 -> Neighbors.Three
        else -> Neighbors.MoreTHanThree
    }

fun adjacentCells(grid: Grid): Sequence<Pair<GridCell, Neighbors>> =
    grid.map { focus ->
        // Slow
        focus to neighbors(grid.filter { it != focus && isAdjacent(focus, it) }.map { it.living }.take(9))
    }

fun nextGeneration(grid: Grid): Grid =
    adjacentCells(grid).map { (gridCell, neighbors) -> gridCell.copy(living = evolve(gridCell.living to neighbors)) }


fun main() {
//    Could also use
    val startingGrid = random(200, 200)
//    val startingGrid = from(
//        """
//              |   | O | O | O | O | O | O | O | O | O |   |   |   |   |   | O | O |   | O | O | O |   |   |   |   |   | O |   | O |
//              | O |   |   |   |   |   |   |   |   |   | O |   |   |   | O | O |   | O | O |   |   | O | O | O | O | O | O | O | O | O
//              | O |   |   |   | O | O | O |   |   |   | O |   | O | O | O | O |   |   |   |   | O | O | O | O |   |   |   |   |   | O
//            O |   | O |   |   |   | O |   |   | O |   |   |   | O |   | O | O |   | O |   | O | O | O |   |   |   |   |   | O |   | O
//            O |   |   |   |   |   |   |   |   | O |   |   |   | O |   |   | O |   |   |   | O |   | O |   |   |   |   |   |   |   | O
//            O |   |   |   | O |   | O | O |   |   |   |   |   | O |   | O |   |   |   |   | O |   |   |   |   |   |   |   |   |   | O
//              |   |   |   | O |   |   |   |   | O |   | O |   |   |   | O |   |   |   |   |   |   |   |   |   |   |   | O | O | O |
//            O |   |   |   |   |   |   |   |   |   | O |   |   |   |   |   |   |   | O |   |   |   |   |   | O | O | O |   | O |   |
//            O | O |   |   |   |   |   |   | O | O | O | O |   |   | O |   | O |   | O | O | O |   | O |   |   |   |   | O |   | O |
//              |   |   |   |   |   |   |   |   |   | O |   | O |   |   |   |   | O |   | O |   |   |   |   |   |   |   | O | O |   |
//            O | O |   |   |   |   |   |   | O |   | O |   | O |   | O |   |   | O | O |   | O |   |   | O |   |   |   |   | O |   |
//            O | O |   | O |   |   |   |   | O |   | O |   | O |   | O |   |   |   |   | O | O | O |   |   | O |   | O |   |   |   |
//              |   | O | O | O |   | O | O |   | O |   |   | O |   |   |   |   | O |   | O |   |   | O |   |   |   |   |   | O | O |
//              | O | O |   |   |   |   |   |   |   | O | O | O | O |   |   |   |   |   | O | O | O |   |   |   | O |   | O |   | O | O
//            O |   | O | O |   |   |   | O |   |   |   |   | O |   | O |   |   |   |   |   |   |   |   |   |   | O |   | O |   | O | O
//            O |   |   |   |   | O |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   | O | O | O |   | O |   |   |   | O | O
//              | O | O | O |   | O |   | O |   |   |   |   | O |   |   | O |   | O |   |   |   |   |   |   | O | O |   | O |   | O |
//              | O |   |   |   |   |   |   |   |   |   |   | O | O |   | O |   |   |   |   |   | O |   | O | O |   |   |   | O | O |
//              | O |   |   |   |   | O | O | O | O | O |   | O |   |   |   |   | O |   |   |   |   | O |   | O |   | O |   | O |   |
//            O |   |   |   |   |   |   |   | O |   |   |   | O |   |   |   |   |   |   |   |   |   |   | O | O |   | O |   |   | O |
//            O |   |   |   | O |   | O | O | O | O |   |   | O |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   | O | O |
//              |   | O | O | O | O |   |   |   |   | O | O | O |   |   |   |   |   | O |   |   |   |   |   | O | O | O | O | O |   |
//              |   | O | O |   |   |   |   |   |   |   |   | O |   |   |   |   |   |   |   |   |   |   |   | O | O |   |   |   |   | O
//            O |   |   |   | O |   |   |   |   |   | O |   |   |   |   |   |   |   |   |   |   |   |   | O |   |   | O |   |   |   | O
//            O |   |   |   |   |   |   | O | O |   | O |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   | O |   |   |
//              |   | O |   |   |   | O | O |   |   |   |   | O |   | O |   |   |   |   |   |   | O |   |   |   |   |   | O |   |   | O
//              |   |   |   | O |   | O | O |   |   |   |   | O | O | O |   | O |   |   |   |   |   |   |   |   | O |   | O | O |   | O
//              |   |   | O |   | O | O |   |   |   |   |   |   | O |   | O |   |   |   |   | O | O |   |   |   |   |   |   |   |   | O
//              |   | O |   | O | O |   |   |   |   |   |   |   |   |   |   |   |   | O |   | O |   |   | O | O |   |   |   |   |   |
//            O |   |   |   | O |   |   |   |   |   |   |   |   |   |   |   |   |   | O | O | O | O |   | O |   |   |   |   |   | O | O
//              | O | O |   | O | O |   | O | O |   | O |   | O |   |   |   |   |   |   |   | O | O | O |   |   | O |   | O | O |   |
//    """.trimIndent()
//    )

    val generations = generateSequence(startingGrid, { nextGeneration(it) }).drop(1)

    generations.take(10)
        .forEachIndexed { generationId, grid ->
            println("Generation $generationId")
            println(displayGrid(grid))
            println()
        }
}

// Utils functions

fun Cell.Companion.random(): Cell =
    if (Random.nextBoolean()) Living
    else Dead

fun random(xBound: Int, yBound: Int): Grid =
    (0..xBound)
        .flatMap { x ->  (0..yBound)
            .map { y -> GridCell(living = Cell.random(), x= x, y= y) } }
        .asSequence()

fun from(grid: String): Grid =
    grid
        .split("\n")
        .mapIndexed { y, line ->
            line.split("|")
                .mapIndexed { x, cell ->
                    when (cell.trim()) {
                        "O" -> GridCell(Living, x = x, y = y)
                        else -> GridCell(Dead, x = x, y = y)
                    }
                }
        }
        .flatten()
        .asSequence()

fun displayCell(cell: GridCell): String =
    when (cell.living) {
        Dead -> " "
        Living -> "O"
    }

fun displayGrid(grid: Grid): String =
    grid.groupBy { it.y }
        .map { it.key to it.value.sortedBy { cell -> cell.x } }
        .sortedBy { it.first }
        .joinToString("\n") { (_, cells) -> cells.map(::displayCell).joinToString(" | ") }