private static Instruction GetInstruction(string command, ref InstructionArgs args)
{
Instruction result;
var argString = "";
if (command != null)
{
var argsSeperatorPosition = command.IndexOf(" ", StringComparison.Ordinal);
if (argsSeperatorPosition > 0)
{
argString = command.Substring(argsSeperatorPosition + 1);
command = command.Substring(0, argsSeperatorPosition);
command = command.ToUpper();
}
}
if (Enum.TryParse(command, true, out result))
{
if (result != Instruction.Place)
{
return(result);
}
if (!TryParsePlaceArgs(argString, ref args))
{
result = Instruction.Invalid;
}
}
else
{
result = Instruction.Invalid;
}
return(result);
}
public string Command(string command)
{
var response = "";
InstructionArgs args = null;
var instruction = GetInstruction(command, ref args);
switch (instruction)
{
case Instruction.Place:
var placeArgs = (PlaceArgs)args;
response = _robotAction.Place(placeArgs.X, placeArgs.Y, placeArgs.Facing) ? "Command Success" : _robotAction.Error;
break;
case Instruction.Move:
response = _robotAction.Move() ? "Command Success" : _robotAction.Error;
break;
case Instruction.Left:
response = _robotAction.Left() ? "Command Success" : _robotAction.Error;
break;
case Instruction.Right:
response = _robotAction.Right() ? "Command Success" : _robotAction.Error;
break;
case Instruction.Report:
response = _robotAction.Report();
break;
case Instruction.Invalid:
response = @"Invalid command. The correct command formats are as follows:
PLACE X, Y, DIRECTION
MOVE
RIGHT
LEFT
REPORT
-------------
Please review your input and try again.";
break;
default:
response = @"Invalid command. The correct command formats are as follows:
PLACE X, Y, DIRECTION
MOVE
RIGHT
LEFT
REPORT
-------------
Please review your input and try again.";
break;
}
return(response);
}
private static bool TryParsePlaceArgs(string argString, ref InstructionArgs args)
{
var argParts = argString.Split(',');
int x, y;
Facing facing;
if (argParts.Length != 3 || !TryGetCoordinate(argParts[0], out x) ||
!TryGetCoordinate(argParts[1], out y) || !TryGetFacingDirection(argParts[2], out facing))
{
return(false);
}
args = new PlaceArgs
{
X = x,
Y = y,
Facing = facing,
};
return(true);
}
