/// <summary>
/// Picks a direction that is consitent with the last direction proceeded, if possible.
/// </summary>
public override DirectionEnum PickDirectionToProceed(object mazeSolutionElements, MazeGridpoint mazeGridpoint)
{
var pathToSolveMaze = mazeSolutionElements as List <MazeSolutionElement>;
if (pathToSolveMaze == null)
{
throw new Exception("Maze solution elements used are not supported by BaseDirectionPicker");
}
if (pathToSolveMaze.Any())
{
var lastMazeSolutionElement = pathToSolveMaze.Last();
var lastMazeGridpoint = lastMazeSolutionElement.MazeGridpoint;
var lastDirectionProceeded = lastMazeSolutionElement.DirectionProceeded;
// Find all paths that do not lead back to the last position in the maze on the path traced so far
// AND, are valid positions inside the boundaries of the maze
var potentialDirectionsToProceed = mazeGridpoint.DirectionsAvailable.OpenPaths
.Where(direction =>
MazeToSolve.IsValidPositionInMazeAndNotBacktracking(lastMazeGridpoint, mazeGridpoint, direction)).ToList();
// If it's possible to keep going in a straight line, continue to do so
if (potentialDirectionsToProceed.Contains(lastDirectionProceeded))
{
return(lastDirectionProceeded);
}
return(potentialDirectionsToProceed.FirstOrDefault());
}
// Take the first path that is valid
return(mazeGridpoint.DirectionsAvailable.OpenPaths
.FirstOrDefault(direction =>
MazeToSolve.IsValidPositionInMaze(mazeGridpoint, direction)));
}
private bool IsWallAdjacent(MazeGridpoint mazeGridpoint, DirectionEnum direction)
{
// Start by proceeding in a direction given away from mazeGridpoint
var isWallAdjacent = false;
var nextMazeGridpoint = MazeToSolve.ProceedToNewGridpoint(mazeGridpoint, direction);
// Now, check each direction around the nextMazeGridpoint
foreach (var nextDirection in nextMazeGridpoint.DirectionsAvailable.OpenPaths)
{
if (!MazeToSolve.IsValidPositionInMazeAndNotBacktracking(mazeGridpoint, nextMazeGridpoint, nextDirection))
{
continue;
}
var nextNextMazeGridpoint = MazeToSolve.ProceedToNewGridpoint(nextMazeGridpoint, nextDirection);
if (nextNextMazeGridpoint.HasBeenVisited)
{
continue;
}
if (nextNextMazeGridpoint.IsWall)
{
isWallAdjacent = true;
break;
}
}
return(isWallAdjacent);
}