PowerArgs.TabCompletion.BeforeParse C# (CSharp) Method

BeforeParse() public method

Before PowerArgs parses the args, this hook inspects the command line for the indicator and if found takes over the command line and provides tab completion.
public BeforeParse ( PowerArgs.ArgHook context ) : void
context PowerArgs.ArgHook The context used to inspect the command line arguments.
return void
        public override void BeforeParse(ArgHook.HookContext context)
        {
            if (CompletionSourceType != null &&
                CompletionSourceType.GetInterfaces().Contains(typeof(ITabCompletionSource)) == false &&
                CompletionSourceType.GetInterfaces().Contains(typeof(ISmartTabCompletionSource)) == false)
            {
                throw new InvalidArgDefinitionException("Type does not implement ITabCompletionSource or ISmartTabCompletionSource: " + CompletionSourceType.FullName);
            }

            if (context.Definition.IsNonInteractive)
            {
                this.REPL = false;
                return;
            }
            if (Indicator == "" && context.CmdLineArgs.Length != 0)
            {
                this.REPL = false;
                return;
            }
            if (Indicator != "" && (context.CmdLineArgs.Length != 1 || context.CmdLineArgs[0] != Indicator))
            {
                this.REPL = false;
                return;
            }

            if (REPL && ShowREPLWelcome)
            {
                ConsoleString.Empty.WriteLine();
                var message = REPLWelcomeMessage.Replace("{{Indicator}}", REPLExitIndicator);
                ConsoleString.WriteLine(message, ConsoleColor.Cyan);
                ConsoleString.Empty.WriteLine();
                ConsoleString.Write(Indicator + "> ", ConsoleColor.Cyan);
                ShowREPLWelcome = false;
            }
            else if (REPL)
            {
                ConsoleString.Write(Indicator + "> ", ConsoleColor.Cyan);
            }
            else
            {

                // This is a little hacky, but I could not find a better way to make the tab completion start on the same lime
                // as the command line input
                try
                {
                    var lastLine = StdConsoleProvider.ReadALineOfConsoleOutput(Console.CursorTop - 1);
                    Console.CursorTop--;
                    Console.WriteLine(lastLine);
                    Console.CursorTop--;
                    Console.CursorLeft = lastLine.Length + 1;
                }
                catch (Exception)
                {
                    Console.WriteLine();
                    Console.Write(Indicator + "> ");
                }
            }

            PowerArgsRichCommandLineReader reader = new PowerArgsRichCommandLineReader(context.Definition, LoadHistory());

            IHighlighterConfigurator customConfigurator;
            if(HighlighterConfiguratorType.TryCreate<IHighlighterConfigurator>(out customConfigurator))
            {
                customConfigurator.Configure(reader.Highlighter);
            }

            var newCommandLineString = reader.ReadLine().ToString();
            var newCommandLineArray = Args.Convert(newCommandLineString);

            if (REPL && newCommandLineArray.Length == 1 && string.Equals(newCommandLineArray[0], REPLExitIndicator, StringComparison.OrdinalIgnoreCase))
            {
                throw new REPLExitException();
            }

            if (REPL && newCommandLineArray.Length == 1 && newCommandLineArray[0] == "cls")
            {
                ConsoleProvider.Current.Clear();
                throw new REPLContinueException();
            }

            else if (REPL && newCommandLineArray.Length == 0 && string.IsNullOrWhiteSpace(REPLExitIndicator) == false)
            {
                throw new REPLContinueException();
            }

            context.CmdLineArgs = newCommandLineArray;
            AddToHistory(newCommandLineString);
        }