/// <summary>
/// Executes the commands that have been given to the Robot.
/// </summary>
/// <returns></returns>
public InstructionExecutionResult[] Execute()
{
var instructions = this._commands.Select(cmd => this.ParseCommand(cmd.Trim()));
var ret = instructions
.Select(this.Execute)
.Select(o => new InstructionExecutionResult {
Executed = o.executed, LogMessage = o.log
})
.ToArray();
// Perform a final Report if the user hasn't explicitly issued one himself
if (!(instructions.LastOrDefault() is ReportInstruction))
{
this.Execute(ReportInstruction.Create());
}
return(ret);
}
/// <summary>
/// Parses a string command into an Instruction.
/// </summary>
/// <param name="command">The string command to parse</param>
/// <returns>An concrete Instruction</returns>
private Instruction ParseCommand(string command)
{
// Check which regex matches the command, and therefore derive the command's type
var matchingRegex = this.Regexes
.DefaultIfEmpty(KeyValuePair.Create(InstructionType.Unknown, new Regex("")))
.FirstOrDefault(kvp => kvp.Value.IsMatch(command));
var matchedType = matchingRegex.Key;
var rgx = matchingRegex.Value;
switch (matchedType)
{
default:
case InstructionType.Unknown:
return(NoopInstruction.Create(command));
case InstructionType.Place:
{
var matches = rgx.Match(command);
int x = int.Parse(matches.Groups.ElementAt(1).Value);
int y = int.Parse(matches.Groups.ElementAt(2).Value);
var direction = Enum.Parse <MovementDirection>(matches.Groups.ElementAt(3).Value.ToTitleCase());
return(PlaceInstruction.Create(x, y, direction, command));
}
case InstructionType.Move:
return(MoveInstruction.Create(command));
case InstructionType.Rotate:
{
var matches = rgx.Match(command);
var rotationDirection = matches.Groups.ElementAt(1).Value.ToLower() == "right"
? RotationDirection.Clockwise
: RotationDirection.CounterClockwise;
return(RotateInstruction.Create(rotationDirection, command));
}
case InstructionType.Report:
return(ReportInstruction.Create(command));
}
}
