public static KeyValuePair <string, IArgumentTaker> MakeOption(string optionName, IArgumentTaker argTaker) => new KeyValuePair <string, IArgumentTaker>(optionName, argTaker);
public CommandMatch Match(CommandConfig config, string commandAndArgs, MessageFlags messageFlags)
{
if ((messageFlags & RequiredFlags) != RequiredFlags)
{
// one or more required flags not set
return(null);
}
if ((messageFlags & ForbiddenFlags) != 0)
{
// one or more forbidden flags set
return(null);
}
string commandMatched = null;
foreach (string commandName in CommandNames)
{
if (!commandAndArgs.StartsWith(commandName))
{
// not this command
continue;
}
if (commandAndArgs.Length == commandName.Length)
{
// this command without arguments
commandMatched = commandName;
break;
}
if (char.IsWhiteSpace(commandAndArgs, commandName.Length))
{
// this command followed by whitespace
commandMatched = commandName;
break;
}
}
if (commandMatched == null)
{
// not this command
return(null);
}
string argumentsToGo = commandAndArgs.Substring(commandMatched.Length);
bool keepTakingOptions = true;
ImmutableList <KeyValuePair <string, object> > .Builder seenOptions =
ImmutableList.CreateBuilder <KeyValuePair <string, object> >();
ImmutableList <object> .Builder args = ImmutableList.CreateBuilder <object>();
for (;;)
{
bool optionMatched = false;
if (keepTakingOptions)
{
string startTrimmedToGo = argumentsToGo.TrimStart();
// forced end of options?
if (startTrimmedToGo.StartsWith("--"))
{
if (startTrimmedToGo.Length == 2 || char.IsWhiteSpace(startTrimmedToGo, 2))
{
// lone "--" option; stop taking options
keepTakingOptions = false;
argumentsToGo = startTrimmedToGo.Substring(2);
continue;
}
}
// options
foreach (KeyValuePair <string, IArgumentTaker> option in Options)
{
bool thisOption = false;
if (startTrimmedToGo.StartsWith(option.Key))
{
// might be this option
if (startTrimmedToGo.Length == option.Key.Length)
{
// it is, as the last option
thisOption = true;
}
else
{
Debug.Assert(startTrimmedToGo.Length > option.Key.Length);
if (startTrimmedToGo[option.Key.Length] == '=' || char.IsWhiteSpace(startTrimmedToGo, option.Key.Length))
{
// it is, followed by a space or an equals sign
thisOption = true;
}
}
}
if (!thisOption)
{
// not this one
continue;
}
// attempt to match the value
// (the equals sign, if it follows, is sent to the taker!)
object optValue;
string optRest = option.Value.Take(startTrimmedToGo.Substring(option.Key.Length), out optValue);
if (optRest == null)
{
// the option name matched but its argument didn't
continue;
}
// matched!
seenOptions.Add(new KeyValuePair <string, object>(option.Key, optValue));
argumentsToGo = optRest;
optionMatched = true;
break;
}
}
if (optionMatched)
{
continue;
}
// argument?
IArgumentTaker upcomingArgumentTaker = Arguments
.Skip(args.Count)
.FirstOrDefault();
if (upcomingArgumentTaker == null)
{
// there should be no more arguments
if (argumentsToGo.Trim().Length > 0)
{
// but there are; it's not this command
return(null);
}
// good; let's get out of this loop
break;
}
object argValue;
string argRest = upcomingArgumentTaker.Take(argumentsToGo, out argValue);
if (argRest == null)
{
// taking the argument failed; it's not this command
return(null);
}
args.Add(argValue);
argumentsToGo = argRest;
}
// command parsed successfully
return(new CommandMatch(
this,
commandMatched,
seenOptions.ToImmutable(),
args.ToImmutable(),
messageFlags
));
}
