private string Usage(Type type)
{
VerbAttribute verbAttr = type.GetCustomAttributes <VerbAttribute>().FirstOrDefault();
var options = OptionsClassProcessor.GetOptions(type);
var values = OptionsClassProcessor.GetValues(type);
var restOfInput = OptionsClassProcessor.GetRestOfInputProperty(type);
StringBuilder result = new StringBuilder();
if (verbAttr != null)
{
result.AppendLine(verbAttr.HelpText.SplitToLines(LineWidth + 20, 0) + Environment.NewLine);
}
foreach (var option in options.Values)
{
result.AppendFormat("{0,-20} {1}" + Environment.NewLine,
(option.IsShortOption ? "-" : "--") + option.Option,
option.Description.SplitToLines(LineWidth, PrepadSpaces));
}
foreach (var value in values.Values.OrderBy(v => v.Index))
{
result.AppendFormat("#{0,-19} {1}" + Environment.NewLine,
value.Index,
value.Description.SplitToLines(LineWidth, PrepadSpaces));
}
if (restOfInput != null)
{
result.AppendFormat("{0,-20} {1}" + Environment.NewLine,
"rest of input",
restOfInput.Item2.Description.SplitToLines(LineWidth, PrepadSpaces));
}
return(result.ToString());
}
private static ParseResult <object> SetRestOfInputPropertyIfAvailable(Type type, object instance, Tokenizer tokenizer)
{
var restOfInputProp = OptionsClassProcessor.GetRestOfInputProperty(type);
if (restOfInputProp != null)
{
if (restOfInputProp.Item2.Required && tokenizer.AtEnd)
{
return(ParseResult <object> .WithError("A value for the property '" + restOfInputProp.Item1.Name + "' is missing"));
}
restOfInputProp.Item1.SetValue(instance, tokenizer.RestOfInput);
}
return(null); // No error
}
public ParseResult <object> Parse(IEnumerable <Type> verbTypes, string input)
{
Dictionary <string, Type> verbs = OptionsClassProcessor.GetVerbs(verbTypes);
var tokenizer = new Tokenizer(input);
var token = tokenizer.NextToken;
if (token.Kind != TokenKind.Value)
{
DisplayHelp(verbs, null);
return(ParseResult <object> .WithError("Could not find an expected verb"));
}
if (token.Value == "help")
{
DisplayHelp(verbs, tokenizer);
// The user intentionally asked for help, and this is not an error. The caller has to
// be aware of the option that they are getting a null value in that case.
return(ParseResult <object> .WithValue(null));
}
Type type;
if (!verbs.TryGetValue(token.Value, out type))
{
DisplayHelp(verbs, null);
return(ParseResult <object> .WithError("Could not find a match for verb '" + token.Value + "'"));
}
var result = Parse(type, tokenizer.RestOfInput);
if (!result.Success)
{
_helpWriter.Write(Usage(type));
}
return(result);
}
private ParseResult <object> Parse(Type type, string input)
{
// TODO Refactor this whole thing to use exception handling and store common objects in a class
object instance = Activator.CreateInstance(type);
Dictionary <string, OptionAttribute> options = OptionsClassProcessor.GetOptions(type);
Dictionary <int, ValueAttribute> values = OptionsClassProcessor.GetValues(type);
int unsatisfiedCount = options.Count + values.Count;
int nextValueToFill = 0;
OptionAttribute optionExpectingValue = null;
Tokenizer tokenizer = new Tokenizer(input);
while (!tokenizer.AtEnd && unsatisfiedCount > 0)
{
Token token = tokenizer.NextToken;
switch (token.Kind)
{
case TokenKind.LongOption:
case TokenKind.ShortOption:
if (optionExpectingValue != null)
{
return(ParseResult <object> .WithError("No value provided for option '" + optionExpectingValue.Option + "'"));
}
OptionAttribute optionAttr;
if (!options.TryGetValue(token.Value, out optionAttr))
{
return(ParseResult <object> .WithError("Unexpected option '" + token.Value + "'"));
}
if (optionAttr.Satisfied)
{
return(ParseResult <object> .WithError("Multiple values for option '" + token.Value + "' are not allowed"));
}
var alreadySatisfiedExclusiveOption = FirstAlreadySatisfiedMutuallyExclusiveOption(options, optionAttr);
if (alreadySatisfiedExclusiveOption != null)
{
return(ParseResult <object> .WithError("The option '" + token.Value + "' is mutually exclusive with the option '" + alreadySatisfiedExclusiveOption.Option + "' that was already satisfied"));
}
if (optionAttr.TargetProperty.PropertyType == typeof(bool))
{
optionAttr.TargetProperty.SetValue(instance, true);
optionAttr.Satisfied = true;
--unsatisfiedCount;
}
else
{
optionExpectingValue = optionAttr;
}
break;
case TokenKind.Value:
if (optionExpectingValue != null)
{
string error = SetPropertyValue(optionExpectingValue, instance, token.Value);
if (error != null)
{
return(ParseResult <object> .WithError("Error setting option '" + optionExpectingValue.Option + "': " + error));
}
optionExpectingValue.Satisfied = true;
optionExpectingValue = null;
--unsatisfiedCount;
}
else
{
if (nextValueToFill >= values.Count)
{
// There are no more values to fill, just options
return(ParseResult <object> .WithError("Unexpected plain value '" + token.Value + "'"));
}
ValueAttribute valueAttr = values[nextValueToFill];
string error = SetPropertyValue(valueAttr, instance, token.Value);
if (error != null)
{
return(ParseResult <object> .WithError("Error setting value #" + nextValueToFill + ": " + error));
}
valueAttr.Satisfied = true;
--unsatisfiedCount;
++nextValueToFill;
}
break;
case TokenKind.Error:
return(ParseResult <object> .WithError("Error parsing options: " + token.Value));
}
}
SetDefaultValues(instance, options, values);
var errorResult = FindUnsatisfiedOptionsAndValues(options, values);
if (errorResult != null)
{
return(errorResult);
}
errorResult = SetRestOfInputPropertyIfAvailable(type, instance, tokenizer);
if (errorResult != null)
{
return(errorResult);
}
return(ParseResult <object> .WithValue(instance));
}