/// <summary>
/// Attempts to consume a WhiteSpace token.
/// </summary>
private static Boolean ConsumeWhiteSpace(String input, IList<UvssLexerToken> output, ref Int32 line, ref Int32 ix)
{
if (IsPastEndOfStream(input, ix))
return false;
if (!IsValidStartWhiteSpace(input[ix]))
return false;
var start = ix;
var length = 0;
var newline = false;
do
{
if (input[ix] == '\n')
{
newline = true;
}
ix++;
length++;
} while (ix < input.Length && IsValidInWhiteSpace(input[ix]));
var token = new UvssLexerToken(UvssLexerTokenType.WhiteSpace, start, length, line);
output.Add(token);
if (newline)
{
line++;
}
return true;
}
/// <summary>
/// Attempts to consume a IndexOperator token.
/// </summary>
private static Boolean ConsumeIndexOperator(String input, IList<UvssLexerToken> output, Int32 line, ref Int32 ix)
{
var position = ix;
if (input[position] != '[')
return false;
var start = position;
var length = 0;
position++;
while (true)
{
if (ix >= input.Length)
return false;
if (input[position] == ']')
break;
if (!Char.IsDigit(input[position]))
return false;
length++;
position++;
}
position++;
if (length == 0)
return false;
length += 2;
var value = input.Substring(start, length);
var token = new UvssLexerToken(UvssLexerTokenType.IndexOperator, start, length, line, value);
output.Add(token);
ix = position;
return true;
}
/// <summary>
/// Attempts to consume a String token.
/// </summary>
private static Boolean ConsumeString(String input, IList<UvssLexerToken> output, Int32 line, ref Int32 ix)
{
if (IsPastEndOfStream(input, ix))
return false;
if (input[ix] != '"')
return false;
var start = ix++;
var length = 2;
while (ix < input.Length)
{
if (ix + 1 == input.Length && input[ix] != '"')
{
throw new UvssException(PresentationStrings.StyleSheetSyntaxUnterminatedString.Format(line));
}
var c = input[ix++];
if (c == '"')
break;
length++;
}
var value = input.Substring(start + 1, length - 2);
var token = new UvssLexerToken(UvssLexerTokenType.String, start, length, line, value);
output.Add(token);
return true;
}
/// <summary>
/// Attempts to consume a punctuation token.
/// </summary>
private static Boolean ConsumePunctuation(UvssLexerTokenType type, Char punctuation, String input, IList<UvssLexerToken> output, Int32 line, ref Int32 ix)
{
if (IsPastEndOfStream(input, ix))
return false;
if (input[ix] == punctuation)
{
var token = new UvssLexerToken(type, ix, 1, line);
output.Add(token);
ix++;
return true;
}
return false;
}
/// <summary>
/// Attempts to consume a UniversalSelector token.
/// </summary>
private static Boolean ConsumeUniversalSelector(String input, IList<UvssLexerToken> output, Int32 line, ref Int32 ix)
{
if (IsPastEndOfStream(input, ix))
return false;
if (input[ix] != '*')
return false;
var token = new UvssLexerToken(UvssLexerTokenType.UniversalSelector, ix++, 1, line);
output.Add(token);
return true;
}
/// <summary>
/// Attempts to consume a Number token.
/// </summary>
private static Boolean ConsumeNumber(String input, IList<UvssLexerToken> output, Int32 line, ref Int32 ix)
{
if (IsPastEndOfStream(input, ix))
return false;
if (!Char.IsDigit(input[ix]))
return false;
var start = ix++;
var length = 1;
var dec = false;
while (ix < input.Length && IsValidInNumber(input[ix], ref dec)) { ix++; length++; }
var value = input.Substring(start, length);
var token = new UvssLexerToken(UvssLexerTokenType.Number, start, length, line, value);
output.Add(token);
return true;
}
/// <summary>
/// Attempts to consume an Identifier token or a keyword token.
/// </summary>
private static Boolean ConsumeIdentifierOrKeyword(String input, IList<UvssLexerToken> output, Int32 line, ref Int32 ix, ref Boolean storyboard)
{
if (IsPastEndOfStream(input, ix))
return false;
if (!IsValidStartIdentifier(input[ix]))
return false;
var start = ix++;
var length = 1;
while (ix < input.Length && IsValidInIdentifier(input[ix])) { ix++; length++; }
var tokenType = UvssLexerTokenType.Identifier;
var tokenValue = input.Substring(start, length);
switch (tokenValue.ToLowerInvariant())
{
case "as":
tokenType = UvssLexerTokenType.AsOperator;
break;
}
var token = new UvssLexerToken(tokenType, start, length, line, tokenValue);
output.Add(token);
if (tokenValue.StartsWith("@"))
storyboard = true;
return true;
}
/// <summary>
/// Attempts to consume a LogicalChildSelector token.
/// </summary>
private static Boolean ConsumeLogicalChildSelector(String input, IList<UvssLexerToken> output, Int32 line, ref Int32 ix)
{
if (IsPastEndOfStream(input, ix + 1))
return false;
if (input[ix] != '>' || input[ix + 1] != '?')
return false;
var token = new UvssLexerToken(UvssLexerTokenType.LogicalChildSelector, ix, 2, line);
output.Add(token);
ix += 2;
return true;
}
/// <summary>
/// Attempts to consume a ComparisonOperator token.
/// </summary>
private static Boolean ConsumeComparisonOperator(String input, IList<UvssLexerToken> output, Int32 line, ref Int32 ix)
{
if (IsPastEndOfStream(input, ix))
return false;
var c1 = input[ix];
var c2 = ix + 1 < input.Length ? input[ix + 1] : default(Char);
var op = "";
switch (c1)
{
case '=':
op = "=";
break;
case '<':
if (c2 == '>')
{
op = "<>";
break;
}
if (c2 == '=')
{
op = "<=";
break;
}
op = "<";
break;
case '>':
if (c2 == '=')
{
op = ">=";
break;
}
op = ">";
break;
default:
return false;
}
var token = new UvssLexerToken(UvssLexerTokenType.ComparisonOperator, ix, op.Length, line, op);
output.Add(token);
ix += op.Length;
return true;
}
/// <summary>
/// Attempts to consume a StyleName token.
/// </summary>
private static Boolean ConsumeStyleName(String input, IList<UvssLexerToken> output, Int32 line, ref Int32 ix)
{
if (IsPastEndOfStream(input, ix))
return false;
if (!IsValidStartStyleName(input[ix]))
return false;
var start = ix++;
var length = 1;
var qualified = false;
while (ix < input.Length && IsValidInStyleName(input[ix], ref qualified)) { ix++; length++; }
var value = input.Substring(start, length);
var type = String.Equals(value, "trigger", StringComparison.InvariantCultureIgnoreCase) ? UvssLexerTokenType.TriggerKeyword : UvssLexerTokenType.StyleName;
var token = new UvssLexerToken(type, start, length, line, value);
output.Add(token);
if (type == UvssLexerTokenType.TriggerKeyword)
{
ChangeContext(cachedLexerContext_Trigger);
}
return true;
}
/// <summary>
/// Attempts to consume a MultiLineComment token.
/// </summary>
private static Boolean ConsumeMultiLineComment(String input, IList<UvssLexerToken> output, ref Int32 line, ref Int32 ix)
{
if (IsPastEndOfStream(input, ix))
return false;
if (!IsValidStartMultiLineComment(input, ix))
return false;
var start = ix + 2;
var length = 0;
for (var position = start; position < input.Length; position++)
{
if (input[position] == '\n')
line++;
if (IsValidEndMultiLineComment(input, position))
break;
length++;
}
var totalLength = length + "/**/".Length;
var token = new UvssLexerToken(UvssLexerTokenType.MultiLineComment, ix, totalLength, line, input.Substring(start, length));
output.Add(token);
ix += totalLength;
return true;
}
/// <summary>
/// Throws an exception indicating that an expected token was not found.
/// </summary>
/// <param name="state">The parser state.</param>
/// <param name="token">The invalid token.</param>
/// <param name="expected">The expected token type.</param>
private static void ThrowExpectedToken(UvssParserState state, UvssLexerToken token, UvssLexerTokenType expected)
{
var lineNumber = token.Line;
throw new UvssException(PresentationStrings.StyleSheetSyntaxExpectedToken.Format(lineNumber, token.TokenType, expected));
}
/// <summary>
/// Gets a value indicating whether the specified token is a match for the specified parameters.
/// </summary>
/// <param name="token">The token to evaluate.</param>
/// <param name="type">The desired token type.</param>
/// <param name="value">The desired token value.</param>
/// <returns><c>true</c> if the specified token is a match; otherwise, <c>false</c>.</returns>
private static Boolean MatchToken(UvssLexerToken? token, UvssLexerTokenType type, String value = null)
{
if (token == null)
return false;
if (token.Value.TokenType != type)
return false;
if (value != null && !String.Equals(token.Value.Value, value, StringComparison.OrdinalIgnoreCase))
return false;
return true;
}
/// <summary>
/// Throws an exception if the specified token does not match the specified parameters.
/// </summary>
/// <param name="state">The parser state.</param>
/// <param name="token">The token to evaluate.</param>
/// <param name="type">The desired token type.</param>
/// <param name="value">The desired token value.</param>
private static void MatchTokenOrFail(UvssParserState state, UvssLexerToken? token, UvssLexerTokenType type, String value = null)
{
if (token == null)
ThrowUnexpectedEOF(state);
if (token.Value.TokenType != type)
ThrowExpectedToken(state, token.Value, type);
if (value != null && !String.Equals(token.Value.Value, value, StringComparison.OrdinalIgnoreCase))
ThrowExpectedValue(state, token.Value, value);
}
/// <summary>
/// Throws an exception indicating that an unexpected value was reached.
/// </summary>
/// <param name="state">The parser state.</param>
/// <param name="token">The invalid token.</param>
private static void ThrowUnexpectedValue(UvssParserState state, UvssLexerToken token)
{
var lineNumber = token.Line;
throw new UvssException(PresentationStrings.StyleSheetSyntaxUnexpectedValue.Format(lineNumber, token.Value));
}
