private static IEnumerable <CommandTreeToken> ScanOptions(CommandTreeTokenizerContext context, TextBuffer reader)
{
var result = new List <CommandTreeToken>();
var position = reader.Position;
reader.Consume('-');
context.AddRemaining('-');
if (!reader.TryPeek(out var character))
{
var token = new CommandTreeToken(CommandTreeToken.Kind.ShortOption, position, "-", "-");
throw CommandParseException.OptionHasNoName(reader.Original, token);
}
switch (character)
{
case '-':
var option = ScanLongOption(context, reader, position);
if (option != null)
{
result.Add(option);
}
break;
default:
result.AddRange(ScanShortOptions(context, reader, position));
break;
}
if (reader.TryPeek(out character))
{
// Encountered a separator?
if (character == '=' || character == ':')
{
reader.Read(); // Consume
context.AddRemaining(character);
if (!reader.TryPeek(out _))
{
var token = new CommandTreeToken(CommandTreeToken.Kind.String, reader.Position, "=", "=");
throw CommandParseException.OptionValueWasExpected(reader.Original, token);
}
result.Add(ScanString(context, reader));
}
}
return(result);
}
private static CommandTreeToken ScanString(
CommandTreeTokenizerContext context,
TextBuffer reader,
char[]?stop = null)
{
if (reader.TryPeek(out var character))
{
// Is this a quoted string?
if (character == '\"')
{
return(ScanQuotedString(context, reader));
}
}
var position = reader.Position;
var builder = new StringBuilder();
while (!reader.ReachedEnd)
{
var current = reader.Peek();
if (stop?.Contains(current) ?? false)
{
break;
}
reader.Read(); // Consume
context.AddRemaining(current);
builder.Append(current);
}
var value = builder.ToString();
return(new CommandTreeToken(CommandTreeToken.Kind.String, position, value.Trim(), value));
}
private static IEnumerable <CommandTreeToken> ScanShortOptions(CommandTreeTokenizerContext context, TextBuffer reader, int position)
{
var result = new List <CommandTreeToken>();
while (!reader.ReachedEnd)
{
var current = reader.Peek();
if (char.IsWhiteSpace(current))
{
break;
}
// Encountered a separator?
if (current == '=' || current == ':')
{
break;
}
if (char.IsLetter(current))
{
context.AddRemaining(current);
reader.Read(); // Consume
var value = current.ToString(CultureInfo.InvariantCulture);
result.Add(result.Count == 0
? new CommandTreeToken(CommandTreeToken.Kind.ShortOption, position, value, $"-{value}")
: new CommandTreeToken(CommandTreeToken.Kind.ShortOption, position + result.Count, value, value));
}
else
{
// Create a token representing the short option.
var tokenPosition = position + 1 + result.Count;
var represntation = current.ToString(CultureInfo.InvariantCulture);
var token = new CommandTreeToken(CommandTreeToken.Kind.ShortOption, tokenPosition, represntation, represntation);
throw CommandParseException.InvalidShortOptionName(reader.Original, token);
}
}
if (result.Count > 1)
{
foreach (var item in result)
{
item.IsGrouped = true;
}
}
return(result);
}
private static CommandTreeToken ScanLongOption(CommandTreeTokenizerContext context, TextBuffer reader, int position)
{
reader.Consume('-');
context.AddRemaining('-');
if (reader.ReachedEnd)
{
// Rest of the arguments are remaining ones.
context.Mode = Mode.Remaining;
return(new CommandTreeToken(CommandTreeToken.Kind.Remaining, position, "--", "--"));
}
var name = ScanString(context, reader, new[] { '=', ':' });
// Perform validation of the name.
if (name.Value.Length == 0)
{
throw CommandParseException.LongOptionNameIsMissing(reader, position);
}
if (name.Value.Length == 1)
{
throw CommandParseException.LongOptionNameIsOneCharacter(reader, position, name.Value);
}
if (char.IsDigit(name.Value[0]))
{
throw CommandParseException.LongOptionNameStartWithDigit(reader, position, name.Value);
}
for (var index = 0; index < name.Value.Length; index++)
{
if (!char.IsLetterOrDigit(name.Value[index]) && name.Value[index] != '-' && name.Value[index] != '_')
{
throw CommandParseException.LongOptionNameContainSymbol(reader, position + 2 + index, name.Value[index]);
}
}
return(new CommandTreeToken(CommandTreeToken.Kind.LongOption, position, name.Value, $"--{name.Value}"));
}
private static CommandTreeToken ScanQuotedString(CommandTreeTokenizerContext context, TextBuffer reader)
{
var position = reader.Position;
context.FlushRemaining();
reader.Consume('\"');
var builder = new StringBuilder();
var terminated = false;
while (!reader.ReachedEnd)
{
var character = reader.Peek();
if (character == '\"')
{
terminated = true;
reader.Read();
break;
}
builder.Append(reader.Read());
}
if (!terminated)
{
var unterminatedQuote = builder.ToString();
var token = new CommandTreeToken(CommandTreeToken.Kind.String, position, unterminatedQuote, $"\"{unterminatedQuote}");
throw CommandParseException.UnterminatedQuote(reader.Original, token);
}
var quotedString = builder.ToString();
// Add to the context
context.AddRemaining(quotedString);
return(new CommandTreeToken(
CommandTreeToken.Kind.String,
position, quotedString,
quotedString));
}
