public static bool TryParseStringToken(FbxAsciiFileInfo fbxAsciiFileInfo, out StringToken stringToken)
{
var c = fbxAsciiFileInfo.PeekChar();
if (c != '"')
{
stringToken = null;
return(false);
}
fbxAsciiFileInfo.ReadChar();
var stringBuilder = new StringBuilder();
while (fbxAsciiFileInfo.PeekChar() != '"')
{
stringBuilder.Append(fbxAsciiFileInfo.ReadChar());
if (fbxAsciiFileInfo.IsEndOfStream())
{
throw new FbxException(fbxAsciiFileInfo, "Unexpected end of stream; expecting end quote");
}
}
fbxAsciiFileInfo.ReadChar();
stringToken = new StringToken(stringBuilder.ToString());
return(true);
}
public static bool TryParseNumberToken(FbxAsciiFileInfo fbxAsciiFileInfo, out Token numberToken)
{
var c = fbxAsciiFileInfo.PeekChar();
var isFirst = true;
if (!c.IsDigit(isFirst))
{
numberToken = null;
return(false);
}
var stringBuilder = new StringBuilder();
while (c.IsDigit(isFirst) && !fbxAsciiFileInfo.IsEndOfStream())
{
stringBuilder.Append(fbxAsciiFileInfo.ReadChar());
isFirst = false;
c = fbxAsciiFileInfo.PeekChar();
}
var value = stringBuilder.ToString();
if (!value.TryParseNumberToken(out numberToken))
{
throw new FbxException(fbxAsciiFileInfo, $"Invalid number '{value}'");
}
return(true);
}
public static bool TryParseOperatorToken(FbxAsciiFileInfo fbxAsciiFileInfo, out Token operatorToken)
{
var c = fbxAsciiFileInfo.PeekChar();
if (c.Equals('{'))
{
operatorToken = Token.CreateOpenBrace();
}
else if (c.Equals('}'))
{
operatorToken = Token.CreateCloseBrace();
}
else if (c.Equals('*'))
{
operatorToken = Token.CreateAsterix();
}
else if (c.Equals(','))
{
operatorToken = Token.CreateComma();
}
else
{
operatorToken = null;
return(false);
}
fbxAsciiFileInfo.ReadChar();
return(true);
}
public static bool TryConsumeWhiteSpace(FbxAsciiFileInfo fbxAsciiFileInfo)
{
var c = fbxAsciiFileInfo.PeekChar();
if (!(char.IsWhiteSpace(c) || c.IsLineEnd()))
{
return(false);
}
var stringBuilder = new StringBuilder();
while ((char.IsWhiteSpace(c) || c.IsLineEnd()) && !fbxAsciiFileInfo.IsEndOfStream())
{
stringBuilder.Append(fbxAsciiFileInfo.ReadChar());
c = fbxAsciiFileInfo.PeekChar();
}
return(true);
}
public static bool TryParseCommentToken(FbxAsciiFileInfo fbxAsciiFileInfo, out CommentToken commentToken)
{
var c = fbxAsciiFileInfo.PeekChar();
if (c != ';')
{
commentToken = null;
return(false);
}
var stringBuilder = new StringBuilder();
while (!c.IsLineEnd() && !fbxAsciiFileInfo.IsEndOfStream())
{
stringBuilder.Append(fbxAsciiFileInfo.ReadChar());
c = fbxAsciiFileInfo.PeekChar();
}
commentToken = new CommentToken(stringBuilder.ToString());
return(true);
}
public static bool TryParseIdentifierOrCharToken(FbxAsciiFileInfo fbxAsciiFileInfo, out Token token)
{
var c = fbxAsciiFileInfo.PeekChar();
if (!c.IsIdentifierChar())
{
token = null;
return(false);
}
var stringBuilder = new StringBuilder();
while (c.IsIdentifierChar() && !fbxAsciiFileInfo.IsEndOfStream())
{
stringBuilder.Append(fbxAsciiFileInfo.ReadChar());
c = fbxAsciiFileInfo.PeekChar();
}
TryConsumeWhiteSpace(fbxAsciiFileInfo);
var identifier = stringBuilder.ToString();
if (fbxAsciiFileInfo.PeekChar() == ':')
{
fbxAsciiFileInfo.ReadChar();
token = new IdentifierToken(identifier);
return(true);
}
if (identifier.Equals("T") || identifier.Equals("F") || identifier.Equals("Y") || identifier.Equals("N"))
{
token = new BooleanToken(identifier.Equals("T") || identifier.Equals("Y"));
return(true);
}
throw new FbxException(fbxAsciiFileInfo, "Unexpected '" + identifier + "', expected ':' or a single-char literal");
}