public static CssMedium Parse(String str, IFeatureValidatorFactory factory)
{
var source = new StringSource(str);
var result = source.ParseMedium(factory);
return(source.IsDone ? result : null);
}
public static IEnumerable <CssMedium> ParseMedia(this StringSource source, IFeatureValidatorFactory factory)
{
var current = source.SkipSpacesAndComments();
var media = new List <CssMedium>();
while (!source.IsDone)
{
if (media.Count > 0)
{
if (current != Symbols.Comma)
{
return(null);
}
source.SkipCurrentAndSpaces();
}
var medium = source.ParseMedium(factory);
if (medium == null)
{
return(null);
}
media.Add(medium);
current = source.SkipSpacesAndComments();
}
return(media);
}
public static CssMedium ParseMedium(this StringSource source, IFeatureValidatorFactory factory)
{
source.SkipSpacesAndComments();
var ident = source.ParseIdent();
var inverse = false;
var exclusive = false;
var type = String.Empty;
if (ident != null)
{
if (ident.Isi(CssKeywords.Not))
{
inverse = true;
source.SkipSpacesAndComments();
ident = source.ParseIdent();
}
else if (ident.Isi(CssKeywords.Only))
{
exclusive = true;
source.SkipSpacesAndComments();
ident = source.ParseIdent();
}
}
if (ident != null)
{
type = ident;
source.SkipSpacesAndComments();
var position = source.Index;
ident = source.ParseIdent();
if (ident == null || !ident.Isi(CssKeywords.And))
{
source.BackTo(position);
return(new CssMedium(type, inverse, exclusive));
}
source.SkipSpacesAndComments();
}
var features = new List <IMediaFeature>();
do
{
var start = source.Current;
source.SkipCurrentAndSpaces();
var feature = ParseFeature(source);
var end = source.Current;
if (feature == null ||
start != Symbols.RoundBracketOpen ||
end != Symbols.RoundBracketClose)
{
return(null);
}
var validator = factory?.Create(feature.Name);
feature.AssociateValidator(validator);
features.Add(feature);
source.SkipCurrentAndSpaces();
var position = source.Index;
ident = source.ParseIdent();
if (ident == null || !ident.Isi(CssKeywords.And))
{
source.BackTo(position);
break;
}
source.SkipSpacesAndComments();
}while (!source.IsDone);
return(new CssMedium(type, inverse, exclusive, features));
}
