public static void Visit(
ISelectable root,
string selector,
VisitorCallback visitor)
{
Visit(root, selector, visitor, null);
}
public static void Visit(
ISelectable root,
OrSelector selector,
VisitorCallback visitor,
IndexedPredicate predicate)
{
Visit(
root,
null,
root,
new SelectorTracker(selector),
visitor,
predicate);
}
public static void Visit(
ISelectable root,
string selector,
VisitorCallback visitor,
IndexedPredicate predicate)
{
if (Cache.TryGetValue(selector, out var or))
{
Visit(root, or, visitor, predicate);
return;
}
or = Parser.ParseOrSelector(new TokenStream(Token.Parse(selector)), false);
Cache[selector] = or;
Visit(root, or, visitor, predicate);
}
/// <summary>
/// Initializes a new instance of the <see cref="Visitor{T}"/> class
/// by using the specified <see cref="VisitorCallback{T}"/>.
/// </summary>
/// <param name="callback">
/// A <see cref="VisitorCallback{T}"/> to forwards the <see cref="Visit"/>
/// method.
/// </param>
public Visitor(VisitorCallback <T> callback)
{
callback_ = callback;
}
private static void Visit(
ISelectable current,
ISelectableTree parent,
ISelectable root,
SelectorTracker tracker,
VisitorCallback visitor,
IndexedPredicate predicate)
{
var lines = tracker.Lines;
var linesAlive = 0;
var visit = false;
var tree = current as ISelectableTree;
var pruneable = current as IPruneableSelectableTree;
for (var line = 0; line < lines; line++)
{
if (tracker.IsPruned(line))
{
continue;
}
var(terminal, rule) = tracker.LineState(line);
var isMatch = true;
foreach (var s in rule.ElementSelectors)
{
if (!s.Match(current, parent, root, predicate))
{
isMatch = false;
break;
}
}
if (isMatch)
{
if (terminal)
{
visit = true;
}
else
{
tracker.Advance(line);
}
}
if ((!isMatch || terminal) && rule.HasContextSelector)
{
tracker.Prune(line);
continue;
}
if (pruneable != null)
{
if ((!isMatch || terminal) && pruneable.IsUniqueInPath())
{
var type = rule.TypeSelector;
if (type != null && pruneable.Matches(type))
{
tracker.Prune(line);
continue;
}
}
var pruned = false;
// ReSharper disable once LoopCanBeConvertedToQuery
foreach (var selector in tracker.RemainingRules(line))
{
if (selector.HasContextSelector)
{
tracker.Prune(line);
pruned = true;
break;
}
var type = selector.TypeSelector;
if (type != null && !pruneable.CanContainDescendant(type))
{
tracker.Prune(line);
pruned = true;
break;
}
}
if (!pruned)
{
linesAlive++;
}
}
else
{
linesAlive++;
}
}
if (visit)
{
visitor(current, parent, root);
}
if (linesAlive > 0 && tree != null)
{
foreach (var child in tree.GetChildren())
{
Visit(child, tree, root, tracker.Clone(), visitor, predicate);
}
}
}
