internal TokenStream(TokenList tokens, int length)
{
Tokens = tokens;
_length = length;
}
/// <summary>
/// Global method to compute the Result of a token change
/// </summary>
public static Result TokenizeChange(
ICssTokenizerFactory tokenizerFactory,
TokenList oldTokens,
ITextProvider oldText,
ITextProvider newText,
int changeStart,
int deletedLength,
int insertedLength)
{
Result result = new Result();
char firstInsertedChar = (insertedLength > 0) ? newText[changeStart] : '\0';
result.NewTokens = new TokenList();
result.OldTokens = oldTokens;
result.OldTokenStart = FindTokenToStart(oldTokens, changeStart, firstInsertedChar);
result.OldTokenCount = oldTokens.Count - result.OldTokenStart; // assume delete to EOF
result.OldTokenTextOffset = insertedLength - deletedLength;
result.TokenizationStart = changeStart;
if (result.OldTokenStart < oldTokens.Count)
{
// The first old token may start before the actual text change.
// Adjust where tokenization starts:
result.TokenizationStart = Math.Min(result.TokenizationStart, oldTokens[result.OldTokenStart].Start);
}
// Tokenize until EOF or until the new tokens start matching the old tokens
bool tokenizeUntilEOF = (oldTokens.Count == 0);
// Create and init a streaming tokenizer
ICssTokenizer tokenizer = tokenizerFactory.CreateTokenizer();
int estimatedLength = (tokenizeUntilEOF ? newText.Length - result.TokenizationStart : insertedLength);
tokenizer.InitStream(newText, result.TokenizationStart, estimatedLength, keepWhiteSpace: false);
for (CssToken token = tokenizer.StreamNextToken(); true; token = tokenizer.StreamNextToken())
{
if (token.TokenType != CssTokenType.EndOfFile && !tokenizeUntilEOF &&
token.Start >= changeStart + insertedLength)
{
// This could be a good token for stopping, see if it matches an old token
int oldTokenStart = token.Start - result.OldTokenTextOffset;
int oldTokenIndex = oldTokens.FindInsertIndex(oldTokenStart, beforeExisting: true);
if (oldTokenIndex == oldTokens.Count)
{
tokenizeUntilEOF = true;
}
else
{
CssToken oldToken = oldTokens[oldTokenIndex];
if (oldToken.Start == oldTokenStart && CssToken.CompareTokens(token, oldToken, newText, oldText))
{
result.OldTokenCount = oldTokenIndex - result.OldTokenStart;
break;
}
}
}
result.NewTokens.Add(token);
if (token.TokenType == CssTokenType.EndOfFile)
{
break;
}
}
return(result);
}
internal TokenStream(TokenList tokens)
: this(tokens, -1)
{
}