private static void EraseCell(Coords gridCoords, CellState cellState)
{
if (GridCoordsAreWithinBounds(gridCoords))
{
DrawCharacter(gridCoords, ' ');
}
}
// Any live cell with fewer than two live neighbours dies, as if caused by under-population.
// Any live cell with two or three live neighbours lives on to the next generation.
// Any live cell with more than three live neighbours dies, as if by overcrowding.
// Any dead cell with exactly three live neighbours becomes a live cell, as if by reproduction.
internal static bool CurrentlyAliveCellWillStillBeALiveInTheNextGeneration(Grid currentGrid, Coords coords)
{
var numLiveNeighbours = GetNumLiveNeighbours(currentGrid, coords);
// Rules 1, 2 and 3.
return (numLiveNeighbours == 2 || numLiveNeighbours == 3);
}
internal static bool CurrentlyDeadCellWillBecomeALiveInTheNextGeneration(Grid currentGrid, Coords coords)
{
var numLiveNeighbours = GetNumLiveNeighbours(currentGrid, coords);
// Rule 4.
return (numLiveNeighbours == 3);
}
private bool CellWasDeadInPreviousGrid(Coords coords)
{
var cellHasComeAlive = true;
if (_previousGrid != null)
{
cellHasComeAlive = !_previousGrid.IsLiveCellAt(coords);
}
return cellHasComeAlive;
}
private static void DrawCell(Coords gridCoords, CellState cellState)
{
if (GridCoordsAreWithinBounds(gridCoords))
{
var savedForegroundColor = Console.ForegroundColor;
Console.ForegroundColor = cellState.IsZombie ? ConsoleColor.Magenta : ConsoleColor.Cyan;
DrawCharacter(gridCoords, 'X');
Console.ForegroundColor = savedForegroundColor;
}
}
private static void DrawCharacter(Coords gridCoords, char character)
{
var consoleCoords = GridCoordsToConsoleCoords(gridCoords);
Console.SetCursorPosition(consoleCoords.X, consoleCoords.Y);
Console.Write(character);
}
public void SetUp()
{
_coords = new Coords(12, 13);
}
public void MarkZombieCellAt(Coords coords)
{
_cells[coords] = CellState.ZombieCellState();
}
public void MarkWasPreviouslyAliveCellAt(Coords coords)
{
_cells[coords] = CellState.WasPreviouslyAliveCellState();
}
public bool IsLiveCellAt(Coords coords)
{
return _cells.ContainsKey(coords) && _cells[coords].IsAlive;
}
public bool CellWasPreviouslyAliveAt(Coords coords)
{
return _cells.ContainsKey(coords) && _cells[coords].WasPreviouslyAlive;
}
private bool CellIsDeadInCurrentGrid(Coords coords)
{
return !_currentGrid.IsLiveCellAt(coords);
}
public void AddSeedCellAt(Coords coords)
{
_currentGrid.MarkLiveCellAt(coords);
}
private static int GetNumLiveNeighbours(Grid currentGrid, Coords coords)
{
var coordsOfNeighbours = coords.Neighbours();
return coordsOfNeighbours.Count(currentGrid.IsLiveCellAt);
}
private static bool GridCoordsAreWithinBounds(Coords gridCoords)
{
return Math.Abs(gridCoords.X) <= MaxOffsetFromOriginX &&
Math.Abs(gridCoords.Y) <= MaxOffsetFromOriginY;
}
public void MarkLiveCellAt(Coords coords)
{
_cells[coords] = CellState.AliveCellState();
}
private static Coords GridCoordsToConsoleCoords(Coords coords)
{
return Coords.Create(
MaxOffsetFromOriginX + coords.X,
OverallBoardSizeY - MaxOffsetFromOriginY - coords.Y - 1);
}
private void AssertThatGridContainsExpectedLiveCellsAfterTick(Universe universe, Coords[] setOfExpectedCoords)
{
universe.Tick();
var coordsOfLiveCells = new List<Coords>();
universe.IterateLiveCells((coords, cellState) => coordsOfLiveCells.Add(coords));
Assert.That(setOfExpectedCoords, Is.Unique);
Assert.That(coordsOfLiveCells, Is.Unique);
Assert.That(coordsOfLiveCells.Count(), Is.EqualTo(setOfExpectedCoords.Count()), "Found the wrong number of live cells");
foreach (var expectedCoords in setOfExpectedCoords)
{
var match = coordsOfLiveCells.FirstOrDefault(coords => coords.Equals(expectedCoords));
var message = string.Format("Expected to find a live cell at ({0}, {1})", expectedCoords.X, expectedCoords.Y);
Assert.That(match, Is.Not.Null, message);
}
}