12/refactor the app (#14)

* Add Scalatest for unit testing

* Add scalatest to the project
Add some tests for model layer

* Change Scala version to 2.11.11
Add scoverage

* Add more tests for Board and Cell models

* Fix typos and solve import warnings

* Refactor Cell constructor

* The ApplicationView is refactored to use the model now.

src/main/scala/org/juanitodread/conwaygameoflife/MainApp.scala

@@ -19,9 +19,10 @@
 package org.juanitodread.conwaygameoflife
 
 import javax.swing.SwingUtilities
-import org.juanitodread.conwaygameoflife.view.ApplicationView
 import com.typesafe.scalalogging._
 
+import org.juanitodread.conwaygameoflife.view.ApplicationView
+
 /**
  * Main application. Instantiate the frame in a new Thread
  *

src/main/scala/org/juanitodread/conwaygameoflife/model/Board.scala

@@ -1,6 +1,7 @@
 package org.juanitodread.conwaygameoflife.model
 
 import scala.collection.mutable.ArrayBuffer
+
 import org.juanitodread.conwaygameoflife.model.cell.{
   Cell,
   State
@@ -9,25 +10,25 @@ import org.juanitodread.conwaygameoflife.model.cell.{
 class Board(val size: Int = Board.MinSize) {
   require(size >= Board.MinSize && size <= Board.MaxSize)
 
-  private val board = ArrayBuffer.fill(size, size)(Cell())
+  private var board = createBoard()
+
+  def reset(): Unit = {
+    board = createBoard()
+  }
 
   def cellAt(row: Int, col: Int): Cell = {
     require(isValidCellPosition(row, col))
-    val state = board(row)(col).isDead match {
-      case true => State.Dead
-      case false => State.Alive
-    }
-    Cell(state)
+    Cell(row, col, board(row)(col).state)
   }
 
   def aliveCell(row: Int, col: Int): Unit = {
     require(isValidCellPosition(row, col))
-    board(row)(col) = Cell(State.Alive)
+    board(row)(col) = Cell(row, col, State.Alive)
   }
 
   def deadCell(row: Int, col: Int): Unit = {
     require(isValidCellPosition(row, col))
-    board(row)(col) = Cell(State.Dead)
+    board(row)(col) = Cell(row, col, State.Dead)
   }
 
   def countAliveNeighborsForCell(row: Int, col: Int): Int = {
@@ -43,20 +44,19 @@ class Board(val size: Int = Board.MinSize) {
   def calculateCellState(row: Int, col: Int): State.Value = {
     require(isValidCellPosition(row, col))
     val currentCell = this.cellAt(row, col)
-    (currentCell.isAlive, this.cellShouldAlive(row, col)) match {
-      case (true, true) => State.Alive
+    (currentCell.isAlive, this.countAliveNeighborsForCell(row, col)) match {
+      case (true, 2) => State.Alive
+      case (_, 3) => State.Alive
       case _ => State.Dead
     }
   }
 
-  def cellShouldAlive(row: Int, col: Int): Boolean = {
-    Board.ValidNeighborsCount.contains(this.countAliveNeighborsForCell(row, col))
-  }
-
   override def toString(): String = {
     board.map(row => row.mkString(",")).mkString("\n")
   }
 
+  private def createBoard() = ArrayBuffer.tabulate(size, size)(Cell(_, _))
+
   private def isValidCellPosition(row: Int, col: Int): Boolean = {
     row >= 0 && row < this.size && col >= 0 && col < this.size
   }
@@ -86,7 +86,6 @@ object Board {
   // $COVERAGE-OFF$
   private final val MinSize = 30
   private final val MaxSize = 100
-  private final val ValidNeighborsCount = List(2, 3)
   // $COVERAGE-ON$
 
   def apply() = new Board()

src/main/scala/org/juanitodread/conwaygameoflife/model/cell/Cell.scala

@@ -1,6 +1,6 @@
 package org.juanitodread.conwaygameoflife.model.cell
 
-class Cell(val state: State.Value = State.Dead) {
+class Cell private (val id: String, val state: State.Value = State.Dead) {
 
   def isAlive() = this.state == State.Alive
 
@@ -13,6 +13,15 @@ class Cell(val state: State.Value = State.Dead) {
 }
 
 object Cell {
-  def apply() = new Cell()
-  def apply(state: State.Value) = new Cell(state)
+  private final lazy val IdDelimiter = ":"
+  def apply(row: Int, col: Int) = new Cell(makeId(row, col))
+  def apply(row: Int, col: Int, state: State.Value) = new Cell(makeId(row, col), state)
+
+  def makeId(row: Int, col: Int) = s"$row$IdDelimiter$col"
+  def parseId(id: String) = {
+    val parsedId = id.split(IdDelimiter, 2)
+    if (parsedId.size != 2) throw new IllegalArgumentException()
+
+    (parsedId(0).toInt, parsedId(1).toInt)
+  }
 }