/// <summary>
/// Plays the turn of the current player.
/// </summary>
/// <param name="column">The column to drop the current player's marker.</param>
/// <returns>
/// A TurnResult specifying if the play was invalid,
/// if the result was victory for the current player,
/// if the result is a tie, or if the play was valid
/// resulting the the next turn.
/// </returns>
public TurnResult PlayTurn(int column)
{
var cell = Board.DropInColumn(CurrentPlayer, column);
// placement was invalid
if (cell == null)
{
return(TurnResult.Invalid);
}
// check victory
var condition = Board.CheckVictory(cell);
// if result was not next (victory or tie), return result
if (condition != TurnResult.Next)
{
return(condition);
}
// increment turn, switch players and return that it was a valid move
turn++;
CurrentPlayer = (turn % 2 == 1) ? playerRed : playerYellow;
return(TurnResult.Next);
}