void ParseDecimal()
{
while (true)
{
switch (textData.PeekChar())
{
case ' ':
case '\t':
case '\n':
//Here we ignore whitespace
textData.AdvanceChar();
break;
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
mode = DecimalParseMode.DecimalConstWithNull;
SaveCharacter();
textData.AdvanceChar();
return;
case '0':
mode = DecimalParseMode.NullStartDecimal;
textData.AdvanceChar();
return;
case '+':
case '-':
mode = DecimalParseMode.UnsignedDecimalConst;
SaveCharacter();
textData.AdvanceChar();
return;
case '\0':
MakeWarningMinimal(
"Value cannot be empty",
textData.PeekChar(),
textData.Position,
WarningType.Error);
mode = DecimalParseMode.Ending;
return;
default:
MakeWarning(
"Unknown character! There can only be digit or sign.",
textData.PeekChar(),
textData.Position,
WarningType.Error);
textData.AdvanceChar();
break;
}
}
}
public DecimalParserStatus ParseDecimalConst(TextData data)
{
mode = DecimalParseMode.DecimalConst;
warnings = new LinkedList <Warning>();
textData = data;
resultString = new StringBuilder();
while (true)
{
switch (mode)
{
case DecimalParseMode.DecimalConst:
ParseDecimal();
break;
case DecimalParseMode.UnsignedDecimalConst:
ParseUnsignedDecimal();
break;
case DecimalParseMode.DecimalConstWithNull:
ParseUnsignedDecimalWithNull();
break;
case DecimalParseMode.UnsignedIntegerWithExponent:
ParseUnsignedIntegerWithExponent();
break;
case DecimalParseMode.NullStartDecimal:
ParseNullStartDecimal();
break;
case DecimalParseMode.Ending:
return(new DecimalParserStatus(
warnings.All(x => x.WarningType != WarningType.Error),
warnings,
resultString.ToString()));
case DecimalParseMode.UnsignedInteger:
ParseUnsignedInteger();
break;
case DecimalParseMode.NullStartInteger:
ParseNullStartInteger();
break;
case DecimalParseMode.SignedInteger:
ParseSignedInteger();
break;
case DecimalParseMode.UnsignedIntegerWithNull:
ParseUnsignedIntegerWithNull();
break;
default:
throw new NotImplementedException();
}
}
}
void ParseSignedInteger()
{
while (true)
{
switch (textData.PeekChar())
{
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
mode = DecimalParseMode.UnsignedIntegerWithNull;
SaveCharacter();
textData.AdvanceChar();
return;
case '0':
mode = DecimalParseMode.NullStartInteger;
textData.AdvanceChar();
return;
case '+':
case '-':
mode = DecimalParseMode.UnsignedInteger;
SaveCharacter();
textData.AdvanceChar();
return;
case '\0':
case ' ':
case '\t':
case '\n':
MakeWarningMinimal(
"Exponent cannot be empty",
textData.PeekChar(),
textData.Position,
WarningType.Error);
mode = DecimalParseMode.Ending;
return;
default:
MakeWarning(
"Unknown character! There can only be digit from 0 to 9 or sign",
textData.PeekChar(),
textData.Position,
WarningType.Error);
textData.AdvanceChar();
break;
}
}
}
void ParseNullStartInteger()
{
while (true)
{
switch (textData.PeekChar())
{
case '0':
MakeWarning(
"Null at the beginning is excess",
textData.PeekChar(),
textData.Position,
WarningType.Warning);
textData.AdvanceChar();
break;
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
mode = DecimalParseMode.UnsignedIntegerWithNull;
SaveCharacter();
MakeWarning(
"Null at the beginning is excess",
textData.PeekChar(),
textData.Position,
WarningType.Warning);
textData.AdvanceChar();
return;
case '\0':
case ' ':
case '\t':
case '\n':
SaveCharacter('0');
mode = DecimalParseMode.Ending;
return;
default:
MakeWarning(
"Unknown character! There can only be digit from 0 to 9 or sign",
textData.PeekChar(),
textData.Position,
WarningType.Error);
textData.AdvanceChar();
break;
}
}
}
void ParseUnsignedIntegerWithExponent()
{
while (true)
{
switch (textData.PeekChar())
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
SaveCharacter();
textData.AdvanceChar();
break;
case 'E':
case 'e':
mode = DecimalParseMode.SignedInteger;
SaveCharacter();
textData.AdvanceChar();
return;
case '\0':
case ' ':
case '\t':
case '\n':
mode = DecimalParseMode.Ending;
return;
default:
MakeWarning(
"Unknown character! There can only be digit from 0 to 9",
textData.PeekChar(),
textData.Position,
WarningType.Error);
textData.AdvanceChar();
break;
}
}
}
