/// <summary>
/// Run the Report command. Can be overridden.
/// </summary>
/// <returns>CommandResult</returns>
protected virtual GenericResult DoReport(ParseCommandResult parseCommandResult)
{
GenericResult result = new GenericResult();
result.Output = _currentState.ToString();
result.Success = true;
return(result);
}
/// <summary>
/// Run the Right command. Can be overridden.
/// </summary>
/// <param name="parseCommandResult"></param>
/// <returns>CommandResult</returns>
protected virtual GenericResult DoRight(ParseCommandResult parseCommandResult)
{
GenericResult result = new GenericResult();
var newDirection = RotateDirection(90);
var newState = CloneGridItem(_currentState);
newState.Facing = newDirection;
AddItemStateToHistory(newState);
result.Success = true;
return(result);
}
/// <summary>
/// Run the Place command. Can be overridden.
/// </summary>
/// <param name="parseCommandResult"></param>
/// <returns>CommandResult</returns>
protected virtual GenericResult DoPlace(ParseCommandResult parseCommandResult)
{
GenericResult result = new GenericResult();
// Check if the new coords are within the boundary of the grid.
if (_taskGrid.IsInGridBounds(parseCommandResult.Coordinates))
{
var newState = new GridItemState()
{
Coords = parseCommandResult.Coordinates, Facing = parseCommandResult.FacingDirection
};
AddItemStateToHistory(newState);
result.Success = true;
}
else
{
result.Comment = $"That command would position the {GRID_ITEM_TYPE_NAME} off the grid. Try again.";
}
return(result);
}
/// <summary>
/// Run the Move command. Can be overridden.
/// </summary>
/// <returns>CommandResult</returns>
protected virtual GenericResult DoMove(ParseCommandResult parseCommandResult)
{
GenericResult result = new GenericResult();
// Get direction of item, and how to calculate the move.
var newCoordsForMove = _currentState.GetCoordinatesForNextMove();
// check if the new coords are within the boundary of the grid.
if (_taskGrid.IsInGridBounds(newCoordsForMove))
{
var newState = CloneGridItem(_currentState);
newState.Coords = newCoordsForMove;
AddItemStateToHistory(newState);
result.Success = true;
}
else
{
result.Comment = $"That move would position the {GRID_ITEM_TYPE_NAME} off the grid. Try another command. Current position: {_currentState.ToString()}";
}
return(result);
}
/// <summary>
/// Parse the command string to ParseCommandResult
/// </summary>
/// <param name="command"></param>
/// <returns>ParseCommandResult</returns>
protected ParseCommandResult ParseCommand(string command)
{
ParseCommandResult result = new ParseCommandResult();
// Regex match for at least 1 whole word. Group the first word, and the rest (if there is any other text) in another group.
Match match = Regex.Match(command.ToUpper(), @"([A-Z]+)(.*)");
if (match.Success)
{
// The first group is the base command.
var commandWord = match.Groups[1].Value;
// Any parameters will be in the 2nd group, if present.
var parameters = string.Empty;
if (match.Groups.Count == 3)
{
parameters = match.Groups[2].Value;
}
if (Enum.TryParse(commandWord, out CommandType thisCommand))
{
// Command found.
result.Command = thisCommand;
switch (thisCommand)
{
case CommandType.PLACE:
// Regex match for '[digit],[digit],[WHOLEWORD]' i.e. 1,2, NORTH - ignoring any white spaces.
Match matchParams = Regex.Match(parameters, @"\W+(\d+)\W*,\W*(\d+)\W*,\W*([A-Z]+)\w*$");
if (matchParams.Success)
{
if (matchParams.Groups.Count == 4)
{
var x = Convert.ToInt32(matchParams.Groups[1].Value);
var y = Convert.ToInt32(matchParams.Groups[2].Value);
var direction = matchParams.Groups[3].Value;
// Try and parse the direction to FacingDirection enum
if (Enum.TryParse(direction, out FacingDirection facingDirection))
{
result.Coordinates = new Coordinates(x, y);
result.FacingDirection = facingDirection;
result.Success = true;
}
}
}
break;
default:
// Check if any additioanl parameters have been given.
// Note: We could decide to ignore these if we wanted to.
if (string.IsNullOrEmpty(parameters))
{
result.Success = true;
}
else
{
result.Comment = $"The {thisCommand.ToString()} command does not have any parameters. Please try again.";
return(result);
}
break;
}
}
else
{
result.Comment = "No valid command received";
}
}
else
{
result.Comment = "No commands found. Please try again.";
}
return(result);
}