private Instruction GetInstruction(string command, ref PlaceInstructionArguments args)
{
Instruction result;
string argString = "";
int argsSeperatorPosition = command.IndexOf(" ");
if (argsSeperatorPosition > 0)
{
argString = command.Substring(argsSeperatorPosition + 1);
command = command.Substring(0, argsSeperatorPosition);
}
command = command.ToUpper();
if (Enum.TryParse <Instruction>(command, true, out result))
{
if (result == Instruction.Place)
{
if (!TryParsePlaceArgs(argString, ref args))
{
result = Instruction.Invalid;
}
}
}
else
{
result = Instruction.Invalid;
}
return(result);
}
private bool TryParsePlaceArgs(string argString, ref PlaceInstructionArguments 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))
{
args = new PlaceInstructionArguments
{
X = x,
Y = y,
Facing = facing,
};
return(true);
}
return(false);
}
public string Command(string command)
{
string response = "";
PlaceInstructionArguments args = null;
var instruction = GetInstruction(command, ref args);
switch (instruction)
{
case Instruction.Place:
var placeArgs = (PlaceInstructionArguments)args;
if (Robot.Place(placeArgs.X, placeArgs.Y, placeArgs.Facing))
{
response = "Done.";
}
else
{
response = Robot.LastError;
}
break;
case Instruction.Move:
if (Robot.Move())
{
response = "Done.";
}
else
{
response = Robot.LastError;
}
break;
case Instruction.Left:
if (Robot.Left())
{
response = "Done.";
}
else
{
response = Robot.LastError;
}
break;
case Instruction.Right:
if (Robot.Right())
{
response = "Done.";
}
else
{
response = Robot.LastError;
}
break;
case Instruction.Report:
response = Robot.Report();
break;
default:
response = "Invalid command.";
break;
}
return(response);
}
