/// <summary> Return the verb information of the given <paramref name="optionType"/>. </summary>
private static VerbInfo GetVerb(Type optionType, VerbAttribute verb)
{
PropertyInfo[] optionPropertySet = optionType.GetProperties();
OptionInfo[] optionSet = new OptionInfo[optionPropertySet.Length];
int p = 0;
for (int i = -1; ++i != optionPropertySet.Length;)
{
PropertyInfo property = optionPropertySet[i];
OptionAttribute optAttr = property.GetCustomAttribute <OptionAttribute>();
if (optAttr == null)
{
continue;
}
optionSet[p++] = new OptionInfo(property, optAttr);
}
Array.Resize(ref optionSet, p);
return(new VerbInfo(optionType, verb, optionSet));
}
/// <summary>
/// Returns the verb information of the given <paramref name="verb"/> that may
/// match an element of the given <paramref name="optionTypes"/>. If no matching
/// element is found, NULL is returned.
/// </summary>
private static VerbInfo GetVerb(string verb, Type[] optionTypes)
{
if (verb == null)
{
return(GetVerb(optionTypes[0], null));
}
for (int i = -1; ++i != optionTypes.Length;)
{
Type optionType = optionTypes[i];
VerbAttribute verbAttr = optionType.GetCustomAttribute <VerbAttribute>();
if (verbAttr == null)
{
continue;
}
if (!string.Equals(verb, verbAttr.Name, StringComparison.InvariantCultureIgnoreCase))
{
continue;
}
return(GetVerb(optionType, verbAttr));
}
return(null);
}
/// <summary>
/// Writes the help (usage) information including the specified <paramref name="errorText"/>
/// to the assigned <paramref name="stream"/> for the given set of <paramref name="optionTypes"/>.
/// Note, the <paramref name="errorText"/> is only written when it's not NULL.
/// Returns always FALSE for fluent signature.
/// </summary>
private static bool PrintUsageWithError(TextWriter stream, string errorText, Type[] optionTypes, VerbInfo verbNfo)
{
if (stream == null)
{
return(false);
}
const int padRight = 50;
const string leftOffset = " ";
const string midOffset = " ";
Assembly myAssembly = Assembly.GetEntryAssembly() ?? Assembly.GetCallingAssembly();
FileVersionInfo fileVersionNfo = FileVersionInfo.GetVersionInfo(myAssembly.Location);
string name = fileVersionNfo.ProductName;
string version = fileVersionNfo.ProductVersion;
string copyright = fileVersionNfo.LegalCopyright;
stream.WriteLine($"{name} {version}");
stream.WriteLine(copyright);
stream.WriteLine();
if (!string.IsNullOrEmpty(errorText))
{
stream.WriteLine("ERROR(S)");
stream.WriteLine($" {errorText}");
stream.WriteLine();
}
stream.WriteLine("ARGUMENT(S)");
// No-verb mode?
if (verbNfo == null && optionTypes.Length == 1)
{
verbNfo = GetVerb(optionTypes[0], null);
}
// Print verb information
if (verbNfo == null)
{
int maxVerbNameChars = 0;
VerbInfo[] verbSet = new VerbInfo[optionTypes.Length];
int p = 0;
for (int i = -1; ++i != optionTypes.Length;)
{
Type optionType = optionTypes[i];
VerbAttribute verbAttr = optionType.GetCustomAttribute <VerbAttribute>();
if (verbAttr == null)
{
continue;
}
VerbInfo optVerbNfo = GetVerb(optionType, verbAttr);
maxVerbNameChars = Math.Max(maxVerbNameChars, optVerbNfo.GetName().Length);
verbSet[p++] = optVerbNfo;
}
Array.Resize(ref verbSet, p);
for (int i = -1; ++i != p;)
{
VerbInfo verbOpt = verbSet[i];
string fullline = string.Concat(
leftOffset,
verbOpt.GetName().PadLeft(maxVerbNameChars),
midOffset,
verbOpt.GetHelpText().PadRight(padRight)
);
stream.WriteLine(fullline);
stream.WriteLine();
}
stream.WriteLine("Unknown action. Check help!");
return(false);
}
// Print option information
OptionInfo[] options = verbNfo.GetOptions();
string[] headlines = new string[options.Length];
string[] bodylines = new string[options.Length];
int maxOptionNameChars = 0;
for (int i = -1; ++i != options.Length;)
{
OptionInfo option = options[i];
string shortName = option.GetShortName();
string fullName = option.GetFullName();
string required = option.IsRequired() ? "(Required) " : string.Empty;
string deflt = option.GetDefaultValue() != null ? $"(Default {option.GetDefaultValue()}) " : string.Empty;
string helpText = option.GetHelpText();
bool hasShortName = !string.IsNullOrEmpty(shortName);
bool hasFullName = !string.IsNullOrEmpty(fullName);
string headline = string.Empty;
if (hasShortName)
{
headline = string.Concat(headline, "-", shortName);
}
if (hasShortName && hasFullName)
{
headline = string.Concat(headline, ", ");
}
if (hasFullName)
{
headline = string.Concat(headline, "--", fullName);
}
maxOptionNameChars = Math.Max(maxOptionNameChars, headline.Length);
headlines[i] = headline;
string bodyline = string.Concat(required, deflt, helpText);
bodylines[i] = bodyline;
}
for (int i = -1; ++i != headlines.Length;)
{
string headline = headlines[i];
string bodyline = bodylines[i];
string fullline = string.Concat(
leftOffset,
headline.PadLeft(maxOptionNameChars),
midOffset,
bodyline.PadRight(padRight)
);
stream.WriteLine(fullline);
stream.WriteLine();
}
stream.WriteLine("Missing arguments. Check help!");
return(false);
}
/// <inheritdoc />
public VerbInfo(Type optionType, VerbAttribute attribute, OptionInfo[] options)
{
_optionType = optionType;
_attribute = attribute;
_options = options;
}
