public InputInfo GetValidatedCommand(string cmdStr, ref bool isFirstCmd)
{
// Convert cmdVal to InputInfo for easier binding
var result = new InputInfo();
// Validate Command Keyword
if (String.IsNullOrEmpty(cmdStr)) throw new Exception("Invalid command. Please use:\n PLACE X,Y,F \n MOVE \n LEFT \n RIGHT \n REPORT");
// Parse the cmdStr
var inVals = cmdStr.Trim().ToUpper().Split(new char[] { ' ', ',' }, StringSplitOptions.RemoveEmptyEntries);
// Validate command key
if (!Enum.IsDefined(typeof(Commands), inVals[0])) throw new Exception("Invalid command. Please use any of the keywords: PLACE, MOVE, LEFT, RIGHT, REPORT");
// Return a valid Commands Enum
result.CmdKey = (Commands)Enum.Parse(typeof(Commands), inVals[0]);
// Check a valid first command
if (isFirstCmd && result.CmdKey != Commands.PLACE) throw new Exception("Invalid first command. Please start with PLACE X,Y,F");
// To check consecutive PLACE command any times after the very first entry is done
if (result.CmdKey == Commands.PLACE)
{
// validate cmd
if (inVals.Length != 4) throw new Exception("Invalid PLACE command, Please start with PLACE X, Y, F");
// validate X value
int xval = 0;
if (!int.TryParse(inVals[1], out xval)) throw new Exception("X value must be a number");
if (xval < minVal || xval > maxVal) throw new Exception("X value must be between " + minVal + " and " + maxVal);
// validate Y value
int yval = 0;
if (!int.TryParse(inVals[2], out yval)) throw new Exception("Y value must be a number");
if (yval < minVal || yval > maxVal) throw new Exception("Y value must be between " + minVal + " and " + maxVal);
// validate F value
if (!Enum.IsDefined(typeof(Directions), inVals[3])) throw new Exception("F value must be of " + string.Join(", ", Enum.GetNames(typeof(Directions))));
result.XVal = xval;
result.YVal = yval;
result.FVal = (Directions)Enum.Parse(typeof(Directions), inVals[3]);
// If all passed then set it to false
if(isFirstCmd)
isFirstCmd = false;
}
return result;
}
private RobotPosition Turning(InputInfo inputInfo, Turns turnTo)
{
// get currently facing configs
var conf = FindPlacementConfig(_robotAt.Facing);
// Get the current facing value and +1 to it
var newFacingVal = (int)conf.FacingVal + (int)turnTo;
// Check for valid turn since can keep turning the same direction 360 again and again
// if keep turing RIGHT +1
if (newFacingVal > 4)
newFacingVal = 1;
// if keep turning LEFT -1
if (newFacingVal <= 0)
newFacingVal = 4;
// Get the Directions of newFacingVal
string newDirectionName = Enum.GetName(typeof(Directions), newFacingVal);
Directions newDirection;
Enum.TryParse(newDirectionName, out newDirection);
// Update the current Robot facing value
_robotAt.Facing = newDirection;
return _robotAt;
}
private RobotPosition Move(InputInfo inputInfo)
{
var conf = FindPlacementConfig(_robotAt.Facing);
// Validate the new coordinates before assigning to RoboNow
var newX = _robotAt.XVal + conf.XVal;
var newY = _robotAt.YVal + conf.YVal;
if (IsValidXY(newX, newY))
{
// Assign new values to RoboNow
_robotAt.XVal = newX;
_robotAt.YVal = newY;
}
return _robotAt;
}
private RobotPosition Place(InputInfo inputInfo)
{
if (_robotAt == null) throw new Exception("Robot hasnt been initialize yet.");
_robotAt.XVal = inputInfo.XVal.GetValueOrDefault();
_robotAt.YVal = inputInfo.YVal.GetValueOrDefault();
_robotAt.Facing = inputInfo.FVal;
return _robotAt;
}
public string PerformAction(InputInfo inputInfo)
{
switch (inputInfo.CmdKey)
{
case Commands.PLACE:
_robotAt = Place(inputInfo);
break;
case Commands.MOVE:
_robotAt = Move(inputInfo);
break;
case Commands.LEFT:
_robotAt = Turning(inputInfo, Turns.Left);
break;
case Commands.RIGHT:
_robotAt = Turning(inputInfo, Turns.Right);
break;
case Commands.REPORT:
return GetRobotAt(_robotAt);
break;
default:
return("Oops something gone wrong!");
break;
}
return string.Empty;
}