private static Selector LoadSingleSelector(StyleSheet sheet, Css.Value value, List <Selector> all)
{
// Create the selector:
Selector selector = new Selector();
selector.Value = value;
if (sheet != null)
{
// Default NS:
selector.Namespace = sheet.Namespace;
}
List <LocalMatcher> locals = null;
List <RootMatcher> roots = new List <RootMatcher>();
RootMatcher currentRoot = null;
// Current state:
bool nextTarget = false;
bool wasWhitespace = false;
int max = value.Count;
SelectorMatcher addMatcher = null;
RootMatcher addRoot = null;
// For each selector fragment..
for (int i = 0; i < max; i++)
{
Css.Value current = value[i];
if (current == null)
{
// Happens right at the end where the block was.
continue;
}
if (current.GetType() == typeof(SquareBracketUnit))
{
// [attr]
SquareBracketUnit attrib = current as SquareBracketUnit;
// Make the match object:
AttributeMatch match = attrib.GetMatch();
addMatcher = match;
}
else if (current.Type == ValueType.Text)
{
// Selector fragment.
string text = current.Text;
if (text == " ")
{
wasWhitespace = true;
continue;
}
if (text == "#")
{
// ID selector next.
i++;
string id = value[i].Text;
// Create ID root:
addRoot = new RootIDMatcher();
addRoot.Text = id;
}
else if (text == ".")
{
// Class selector next.
i++;
string className = value[i].Text;
// Create class root:
addRoot = new RootClassMatcher();
addRoot.Text = className;
// Note that if you chain multiple class selectors (.a.b)
// This is called twice and PreviousMatcher/NextMatcher remain null.
// It then simply doesn't change element (which is what we want!).
}
else if (text == "*")
{
// Apply last locals:
if (currentRoot != null && locals != null)
{
currentRoot.SetLocals(locals);
locals.Clear();
}
// Everything:
currentRoot = CreateUniversal(roots);
}
else if (text == ":")
{
// Pseudo class or function next. May also be another colon.
// after and before map to actual style properties.
i++;
current = value[i];
if (current != null && !current.IsFunction)
{
string keywordText = current.Text;
// Second colon?
if (keywordText == ":")
{
// Skip the double colon.
i++;
current = value[i];
keywordText = current.Text;
}
// Keyword?
current = CssKeywords.Get(keywordText.ToLower());
}
if (current == null)
{
// Selector failure - return a blank one.
if (all != null)
{
all.Clear();
}
return(null);
}
// Convert the value into a matcher:
SelectorMatcher sm = current.GetSelectorMatcher();
if (sm == null)
{
// Selector failure - return a blank one.
if (all != null)
{
all.Clear();
}
return(null);
}
// Add it!
addMatcher = sm;
}
else if (text == ">")
{
// Following "thing" being a direct child.
addMatcher = new DirectParentMatch();
}
else if (text == ">>")
{
// Following "thing" being a descendant (same as space).
addMatcher = new ParentMatch();
}
else if (text == "|")
{
// Namespace declaration was before.
// Selector's namespace name is the latest root:
string nsName = currentRoot.Text;
// Pop the root:
roots.RemoveAt(roots.Count - 1);
if (roots.Count > 0)
{
currentRoot = roots[roots.Count - 1];
}
else
{
currentRoot = null;
}
// Note: It's null for * which we can just ignore.
if (nsName != null && sheet != null && sheet.Namespaces != null)
{
// Get the namespace:
CssNamespace ns;
sheet.Namespaces.TryGetValue(nsName.ToLower(), out ns);
selector.Namespace = ns;
}
}
else if (text == "!")
{
// CSS selectors level 4 selector target.
nextTarget = true;
continue;
}
else if (text == "+")
{
// Whenever this follows the following "thing" directly.
addMatcher = new DirectPreviousSiblingMatch();
}
else if (text == "~")
{
// Whenever this follows the following "thing".
addMatcher = new PreviousSiblingMatch();
}
else
{
// It's just a tag:
string tag = text.ToLower();
// Create tag root:
addRoot = new RootTagMatcher();
addRoot.Text = tag;
}
}
if (addRoot != null)
{
if (currentRoot != null && locals != null)
{
currentRoot.SetLocals(locals);
locals.Clear();
}
if (currentRoot != null && wasWhitespace && currentRoot.NextMatcher == null)
{
// Space before it!
// Following "thing" being a descendant.
currentRoot.NextMatcher = new ParentMatch();
currentRoot.NextMatcher.Selector = selector;
wasWhitespace = false;
}
// Add to root set:
roots.Add(addRoot);
currentRoot = addRoot;
// Set selector:
addRoot.Selector = selector;
// Clear:
addRoot = null;
}
if (addMatcher != null)
{
// Always clear whitespace:
wasWhitespace = false;
// Create implicit *:
if (roots.Count == 0)
{
if (currentRoot != null && locals != null)
{
currentRoot.SetLocals(locals);
locals.Clear();
}
currentRoot = CreateUniversal(roots);
}
// Set selector:
addMatcher.Selector = selector;
if (addMatcher is StructureMatcher)
{
// Structural matcher:
currentRoot.NextMatcher = addMatcher as StructureMatcher;
}
else if (addMatcher is PseudoSelectorMatch)
{
// Pseudo matcher:
selector.PseudoElement = addMatcher as PseudoSelectorMatch;
}
else if (addMatcher is LocalMatcher)
{
if (locals == null)
{
locals = new List <LocalMatcher>();
}
// Local matcher:
locals.Add(addMatcher as LocalMatcher);
}
addMatcher = null;
}
if (nextTarget && currentRoot != null)
{
nextTarget = false;
// Update target:
currentRoot.IsTarget = true;
selector.Target = currentRoot;
}
}
// Apply last locals:
if (currentRoot != null && locals != null)
{
currentRoot.SetLocals(locals);
locals.Clear();
}
// Always ensure at least 1:
if (roots.Count == 0)
{
// *:
CreateUniversal(roots);
}
// Update selector info now:
selector.Roots = roots.ToArray();
selector.RootCount = roots.Count;
selector.LastRoot = roots[roots.Count - 1];
selector.FirstRoot = roots[0];
// Set target if needed:
if (selector.Target == null)
{
// Last root is the target:
selector.Target = selector.LastRoot;
selector.Target.IsTarget = true;
}
// Go through them backwards applying PreviousMatcher too:
// (Not including 0).
for (int i = roots.Count - 1; i > 0; i--)
{
// Hook up:
roots[i].PreviousMatcher = roots[i - 1].NextMatcher;
}
if (sheet != null)
{
// Compute specifity now:
selector.GetSpecifity(sheet.Priority);
}
// Add to all set, if there is one:
if (all != null && all.Count == 0)
{
all.Add(selector);
}
return(selector);
}
/// <summary>Reads a single selector matcher. E.g. :hover or .test</summary>
public static SelectorMatcher ReadSelectorMatcher(Css.Value value)
{
if (value == null)
{
return(null);
}
if (value.GetType() == typeof(SquareBracketUnit))
{
// [attr]. Make the match object:
return((value as SquareBracketUnit).GetMatch());
}
// Selector fragment.
string text = value[0].Text;
RootMatcher result = null;
if (text == "#")
{
// ID selector next.
string id = value[1].Text;
// Create ID root:
result = new RootIDMatcher();
result.Text = id;
return(result);
}
else if (text == ".")
{
// Class selector next.
string className = value[1].Text;
// Create class root:
result = new RootClassMatcher();
result.Text = className;
return(result);
}
else if (text == "*")
{
// Everything:
return(new RootUniversalMatcher());
}
else if (text == ":")
{
// Pseudo class or function next. May also be another colon.
// after and before map to actual style properties.
Css.Value current = value[1];
if (current != null && !current.IsFunction)
{
string keywordText = current.Text;
// Second colon?
if (keywordText == ":")
{
// Skip the double colon.
current = value[2];
keywordText = current.Text;
}
// Keyword?
current = CssKeywords.Get(keywordText.ToLower());
}
if (current == null)
{
// Selector failure - return a blank one.
return(null);
}
// Convert the value into a matcher:
return(current.GetSelectorMatcher());
}
// It's just a tag:
string tag = text.ToLower();
// Create tag root:
result = new RootTagMatcher();
result.Text = tag;
return(result);
}