private void Solve(System.Random random, MoveList parentMoves, Piece headPiece, IEnumerable <Piece> tail, int depth)
{
var allFieldsTried = false;
var tailList = tail.ToList();
var originalState = CurrentState.GetNewBoardWithCurrentStateAsInitialState();
var emptyCoordinatesToTry = CurrentState.GetAllEmptySpaces();
if (!_optimumScoreFound)
{
do
{
if (CancellationTokenSource.IsCancellationRequested)
{
CancellationTokenSource.Token.ThrowIfCancellationRequested();
}
var ml = parentMoves.Clone();
Coordinate coordinateToTry;
if (SearchOptions.SearchRandomly)
{
coordinateToTry = CurrentState.GetRandomEmptyCoordinate(random, emptyCoordinatesToTry);
}
else
{
coordinateToTry = CurrentState.GetFirstEmptyCoordinateLeftToRightTopToBottom(emptyCoordinatesToTry);
}
emptyCoordinatesToTry.Remove(coordinateToTry);
if (coordinateToTry.Equals(Coordinate.InvalidCoordinate))
{
allFieldsTried = true;
}
else
{
var move = new Move(headPiece, coordinateToTry);
CurrentState.DoMove(move);
ml.Add(move);
if (CurrentState.IsFull())
{
// You lose!
ml = null;
}
else
{
if (tailList.Any())
{
var newHead = tailList.First();
var newTail = tailList.Skip(1);
Solve(random, ml, newHead, newTail, depth + 1);
}
else
{
LastGeneratedSolution = ml;
ml.Score = CurrentState.GetNumberOfFreeSpaces();
if (ml.Score == _maximumScore)
{
_optimumScoreFound = true;
GetCurrentBest = ml;
}
else
{
if (ml.Score > GetCurrentBest.Score)
{
GetCurrentBest = ml;
}
else
{
ml = null;
}
}
if (SolutionCreated != null)
{
SolutionCreated(this, new SolutionCreatedEventArgs {
CurrentBestMoveList = GetCurrentBest,
MaxScore = _maximumScore
});
}
}
}
}
CurrentState.OverwriteBoard(originalState);
} while(!allFieldsTried);
}
}
