/// <summary>
/// Reads bytes until a unescaped closing parenthesis in found. Unescapes escaped parenthesis.
/// Leaves reader on the char following the closing parenthesis.
/// </summary>
/// <param name="r"></param>
/// <returns></returns>
public static byte[] parseBinary(BinaryReverseReader r)
{
MemoryStream ms = new MemoryStream(128); //For writing the decoded binary
byte b = 0;
byte lastb = 0;
bool hasLastByte = false;
//Read bytes, keeping a two-byte shifting buffer so we can decode escaped chars.
while (r.CanReadByte())
{
b = r.ReadByte();
//Look for closing parenthesis
if ((char)b == ')')
{
if (hasLastByte && (char)lastb == '\\')
{
//Escaped parenthesis, skip slash
lastb = 0;
hasLastByte = false;
}
else
{
//Unescaped closing parenthesis! We hit the end!
if (hasLastByte)
{
ms.WriteByte(lastb); //If we still have a byte in the buffer.
}
return(ms.ToArray()); //We hit the end, an unescaped closng parenthesis.
}
}
//Far as I know, nothing else is escaped.
//Write lastb if present.
if (hasLastByte)
{
ms.WriteByte(lastb);
}
//Shift buffer
lastb = b;
hasLastByte = true;
}
throw new TdTaParseException("Hit end of stream without finding closing parenthesis!");
}
/// <summary>
/// Reads bytes until a unescaped closing parenthesis in found. Unescapes escaped parenthesis.
/// Leaves reader on the char following the closing parenthesis.
/// </summary>
/// <param name="r"></param>
/// <returns></returns>
public static byte[] parseBinary(BinaryReverseReader r)
{
MemoryStream ms = new MemoryStream(128); //For writing the decoded binary
byte b = 0;
byte lastb = 0;
bool hasLastByte = false;
//Read bytes, keeping a two-byte shifting buffer so we can decode escaped chars.
while (r.CanReadByte())
{
b = r.ReadByte();
//Look for closing parenthesis
if ((char)b == ')')
{
if (hasLastByte && (char)lastb == '\\')
{
//Escaped parenthesis, skip slash
lastb = 0;
hasLastByte = false;
}
else
{
//Unescaped closing parenthesis! We hit the end!
if (hasLastByte) ms.WriteByte(lastb); //If we still have a byte in the buffer.
return ms.ToArray();//We hit the end, an unescaped closng parenthesis.
}
}
//Far as I know, nothing else is escaped.
//Write lastb if present.
if (hasLastByte) ms.WriteByte(lastb);
//Shift buffer
lastb = b;
hasLastByte = true;
}
throw new TdTaParseException("Hit end of stream without finding closing parenthesis!");
}
/// <summary>
/// Parses tdta contents into tokens. Throws a generic exception if unrecognized tokens are encountered
/// </summary>
/// <param name="r"></param>
/// <returns></returns>
public static Token nextToken(BinaryReverseReader r)
{
if (!r.CanReadByte())
{
return(null);
}
char c = r.ReadChar();
switch (c)
{
case '(': return(new Token(parseBinary(r))); //Binary data. Leading and trailing parens are stripped, and escaped parens are restored to normal.
case '[': return(new Token(TokenType.StartList, c.ToString())); // [ opening list char
case ']': return(new Token(TokenType.EndList, c.ToString())); //Closing list char
}
//<< opening dict
//>> closing dict
if (c == '<' || c == '>')
{
char c2 = r.ReadChar();
if (c2 != c)
{
throw new TdTaParseException("Unrecognized token: " + c + c2, r);
}
if (c == '<')
{
return(new Token(TokenType.StartDict, "<<"));
}
else
{
return(new Token(TokenType.EndDict, ">>"));
}
}
//Dict key (Any non-whitespace, non-[]<> sequence allowed following forward slash)
if (c == '/')
{
StringBuilder sb = new StringBuilder(40);
while (r.CanReadByte())
{
//Peek at the next char to see if it is whitespace
char pc = (char)r.PeekChar();
if (Char.IsWhiteSpace(pc) || pc == '\n' || pc == '[' || pc == ']' || pc == '<' || pc == '>')
{
//We're done.
//Strip the leading slash, create token with name
return(new Token(TokenType.MapKey, sb.ToString()));
}
else
{
//A valid char, append it.
sb.Append(r.ReadChar());
}
}
}
//Integer or double. Ends at whitespace, newline, ], or >
if (Char.IsDigit(c) || c == '-' || c == '.')
{
StringBuilder sb = new StringBuilder(40);
sb.Append(c);
while (r.CanReadByte())
{
//Peek at the next char to see if it is whitespace
char pc = (char)r.PeekChar();
if (Char.IsWhiteSpace(pc) || pc == '\n' || pc == ']' || pc == '>')
{
//We're done. Find out what kind of number it is.
string s = sb.ToString();
//If it has a decimal, it's a double
if (s.Contains('.'))
{
return(new Token(TokenType.Double, double.Parse(s, floatingPointStyle, NumberFormatInfo.InvariantInfo)));
}
else
{
return(new Token(TokenType.Integer, int.Parse(s, NumberStyles.Integer, NumberFormatInfo.InvariantInfo)));
}
}
else if (Char.IsDigit(c) || c == '-' || c == '.')
{
//A valid char, append it.
sb.Append(r.ReadChar());
}
else
{
//Unrecognized char in numeric sq
throw new TdTaParseException("Unrecognized character in numeric sequence: " + sb.ToString() + pc, r);
}
}
}
//Boolean (true|false) parsing
if (c == 't' || c == 'T' || c == 'f' || c == 'F')
{
string s = c.ToString() + r.ReadChar().ToString() + r.ReadChar().ToString() + r.ReadChar().ToString();
char pc = (char)r.PeekChar();
if (s.Equals("true", StringComparison.OrdinalIgnoreCase))
{
return(new Token(TokenType.Boolean, true));
}
else if (s.Equals("fals", StringComparison.OrdinalIgnoreCase) && (pc == 'e' || pc == 'E'))
{
r.ReadChar(); //discard 'e'
return(new Token(TokenType.Boolean, false));
}
else
{
throw new TdTaParseException("Unrecognized boolean value: " + s + pc, r);
}
}
//Whitespace parsing
if (Char.IsWhiteSpace(c) || c == '\n')
{
StringBuilder sb = new StringBuilder(40);
sb.Append(c);
while (r.CanReadByte())
{
//Peek at the next char to see if it is whitespace
char pc = (char)r.PeekChar();
if (Char.IsWhiteSpace(pc) || pc == '\n')
{
sb.Append(r.ReadChar());
}
else
{
//We done.
break;
}
}
return(new Token(TokenType.Whitespace, sb.ToString()));
}
throw new TdTaParseException("Unrecognized token: " + c, r);
}
/// <summary>
/// Parses tdta contents into tokens. Throws a generic exception if unrecognized tokens are encountered
/// </summary>
/// <param name="r"></param>
/// <returns></returns>
public static Token nextToken(BinaryReverseReader r)
{
if (!r.CanReadByte()) return null;
char c = r.ReadChar();
switch (c)
{
case '(': return new Token(parseBinary(r)); //Binary data. Leading and trailing parens are stripped, and escaped parens are restored to normal.
case '[': return new Token(TokenType.StartList, c.ToString()); // [ opening list char
case ']': return new Token(TokenType.EndList, c.ToString()); //Closing list char
}
//<< opening dict
//>> closing dict
if (c == '<' || c == '>')
{
char c2 = r.ReadChar();
if (c2 != c) throw new TdTaParseException("Unrecognized token: " + c + c2,r);
if (c == '<') return new Token(TokenType.StartDict, "<<");
else return new Token(TokenType.EndDict, ">>");
}
//Dict key (Any non-whitespace, non-[]<> sequence allowed following forward slash)
if (c == '/'){
StringBuilder sb = new StringBuilder(40);
while (r.CanReadByte()){
//Peek at the next char to see if it is whitespace
char pc = (char)r.PeekChar();
if (Char.IsWhiteSpace(pc) || pc == '\n' || pc=='[' || pc==']' || pc=='<' || pc=='>'){
//We're done.
//Strip the leading slash, create token with name
return new Token(TokenType.MapKey,sb.ToString());
}else{
//A valid char, append it.
sb.Append(r.ReadChar());
}
}
}
//Integer or double. Ends at whitespace, newline, ], or >
if (Char.IsDigit(c) || c=='-' || c == '.'){
StringBuilder sb = new StringBuilder(40);
sb.Append(c);
while (r.CanReadByte()){
//Peek at the next char to see if it is whitespace
char pc = (char)r.PeekChar();
if (Char.IsWhiteSpace(pc) || pc == '\n' || pc ==']' || pc =='>'){
//We're done. Find out what kind of number it is.
string s = sb.ToString();
//If it has a decimal, it's a double
if (s.Contains('.')){
return new Token(TokenType.Double,double.Parse(s, floatingPointStyle,NumberFormatInfo.InvariantInfo));
}else{
return new Token(TokenType.Integer,int.Parse(s,NumberStyles.Integer,NumberFormatInfo.InvariantInfo));
}
}else if (Char.IsDigit(c) || c=='-' || c == '.'){
//A valid char, append it.
sb.Append(r.ReadChar());
}else{
//Unrecognized char in numeric sq
throw new TdTaParseException("Unrecognized character in numeric sequence: " + sb.ToString() + pc,r);
}
}
}
//Boolean (true|false) parsing
if (c == 't' || c == 'T' || c == 'f' || c == 'F'){
string s = c.ToString() + r.ReadChar().ToString() + r.ReadChar().ToString() + r.ReadChar().ToString();
char pc = (char)r.PeekChar();
if (s.Equals("true", StringComparison.OrdinalIgnoreCase)){
return new Token(TokenType.Boolean,true);
}else if (s.Equals("fals", StringComparison.OrdinalIgnoreCase) && (pc == 'e' || pc == 'E')){
r.ReadChar(); //discard 'e'
return new Token(TokenType.Boolean,false);
}else{
throw new TdTaParseException("Unrecognized boolean value: " + s + pc,r);
}
}
//Whitespace parsing
if (Char.IsWhiteSpace(c) || c == '\n'){
StringBuilder sb = new StringBuilder(40);
sb.Append(c);
while (r.CanReadByte()){
//Peek at the next char to see if it is whitespace
char pc = (char)r.PeekChar();
if (Char.IsWhiteSpace(pc) || pc == '\n'){
sb.Append(r.ReadChar());
}else{
//We done.
break;
}
}
return new Token(TokenType.Whitespace,sb.ToString());
}
throw new TdTaParseException("Unrecognized token: " + c,r);
}