/// <summary>
/// Select from DOM using index. First non-class/tag/id selector will result in this being passed off to GetMatches
/// </summary>
/// <param name="document"></param>
/// <returns></returns>
public IEnumerable <IDomObject> Select(IDomDocument document, IEnumerable <IDomObject> context)
{
if (Selectors == null)
{
throw new ArgumentException("No selectors provided.");
}
if (Selectors.Count == 0)
{
yield break;
}
Document = document;
IEnumerable <IDomObject> lastResult = null;
HashSet <IDomObject> output = new HashSet <IDomObject>();
IEnumerable <IDomObject> selectionSource = context;
// Disable the index if there is no context (e.g. disconnected elements)
bool useIndex = context.IsNullOrEmpty() || !context.First().IsDisconnected;
// Copy the list because it may change during the process
ActiveSelectors = new List <Selector>(Selectors);
for (activeSelectorId = 0; activeSelectorId < ActiveSelectors.Count; activeSelectorId++)
{
var selector = ActiveSelectors[activeSelectorId];
CombinatorType combinatorType = selector.CombinatorType;
SelectorType selectorType = selector.SelectorType;
TraversalType traversalType = selector.TraversalType;
// Determine what kind of combining method we will use with previous selection results
if (activeSelectorId != 0)
{
switch (combinatorType)
{
case CombinatorType.Cumulative:
// do nothing
break;
case CombinatorType.Root:
selectionSource = context;
if (lastResult != null)
{
output.AddRange(lastResult);
lastResult = null;
}
break;
case CombinatorType.Chained:
selectionSource = lastResult;
lastResult = null;
break;
// default (chained): leave lastresult alone
}
}
HashSet <IDomObject> tempResult = null;
IEnumerable <IDomObject> interimResult = null;
string key = "";
if (useIndex && !selector.NoIndex)
{
#if DEBUG_PATH
if (type.HasFlag(SelectorType.Attribute))
{
key = "!" + selector.AttributeName;
type &= ~SelectorType.Attribute;
if (selector.AttributeValue != null)
{
InsertAttributeValueSelector(selector);
}
}
else if (type.HasFlag(SelectorType.Tag))
{
key = "+" + selector.Tag;
type &= ~SelectorType.Tag;
}
else if (type.HasFlag(SelectorType.ID))
{
key = "#" + selector.ID;
type &= ~SelectorType.ID;
}
else if (type.HasFlag(SelectorType.Class))
{
key = "." + selector.Class;
type &= ~SelectorType.Class;
}
#else
if (selectorType.HasFlag(SelectorType.Attribute))
{
key = "!" + (char)DomData.TokenID(selector.AttributeName);
selectorType &= ~SelectorType.Attribute;
if (selector.AttributeValue != null)
{
InsertAttributeValueSelector(selector);
}
}
else if (selectorType.HasFlag(SelectorType.Tag))
{
key = "+" + (char)DomData.TokenID(selector.Tag, true);
selectorType &= ~SelectorType.Tag;
}
else if (selectorType.HasFlag(SelectorType.ID))
{
key = "#" + (char)DomData.TokenID(selector.ID);
selectorType &= ~SelectorType.ID;
}
else if (selectorType.HasFlag(SelectorType.Class))
{
key = "." + (char)DomData.TokenID(selector.Class);
selectorType &= ~SelectorType.Class;
}
#endif
}
// If part of the selector was indexed, key will not be empty. Return initial set from the
// index. If any selectors remain after this they will be searched the hard way.
if (key != String.Empty)
{
int depth = 0;
bool descendants = true;
switch (traversalType)
{
case TraversalType.Child:
depth = selector.ChildDepth;;
descendants = false;
break;
case TraversalType.Filter:
depth = 0;
descendants = false;
break;
case TraversalType.Descendent:
depth = 1;
descendants = true;
break;
}
if (selectionSource == null)
{
interimResult = document.QueryIndex(key + DomData.indexSeparator, depth, descendants);
}
else
{
interimResult = new HashSet <IDomObject>();
foreach (IDomObject obj in selectionSource)
{
((HashSet <IDomObject>)interimResult)
.AddRange(document.QueryIndex(key + DomData.indexSeparator + obj.Path,
depth, descendants));
}
}
}
else if (selectorType.HasFlag(SelectorType.Elements))
{
selectorType &= ~SelectorType.Elements;
HashSet <IDomObject> source = new HashSet <IDomObject>(selectionSource);
interimResult = new HashSet <IDomObject>();
foreach (IDomObject obj in selectionSource)
{
key = DomData.indexSeparator + obj.Path;
HashSet <IDomObject> srcKeys = new HashSet <IDomObject>(document.QueryIndex(key));
foreach (IDomObject match in selector.SelectElements)
{
if (srcKeys.Contains(match))
{
((HashSet <IDomObject>)interimResult).Add(match);
}
}
}
}
// TODO - GetMatch should work if passed with no selectors (returning nothing), now it returns everything
// 12/10/11 - this todo is not verified, much has changed since it was written. TODO confirm this and
// fix if needed. If having the conversation with self again, remove comments and forget it. This is
// an example of why comments can do more harm than good.
if ((selectorType & ~(SelectorType.SubSelectorNot | SelectorType.SubSelectorHas)) != 0)
{
IEnumerable <IDomObject> finalSelectWithin =
interimResult
?? (combinatorType == CombinatorType.Chained ? lastResult : null)
?? selectionSource
?? document.ChildElements;
// if there are no temporary results (b/c there was no indexed selector) then use the whole set
interimResult = GetMatches(finalSelectWithin, selector);
}
// Deal with subselectors: has() and not() test for the presence of a selector within the children of
// an element. This is essentially similar to the manual selection above.
if (selectorType.HasFlag(SelectorType.SubSelectorHas) ||
selectorType.HasFlag(SelectorType.SubSelectorNot))
{
bool isHasSelector = selectorType.HasFlag(SelectorType.SubSelectorHas);
IEnumerable <IDomObject> subSelectWithin = interimResult
?? (combinatorType == CombinatorType.Chained ? lastResult : null)
?? selectionSource;
// subselects are a filter. start a new interim result.
HashSet <IDomObject> filteredResults = new HashSet <IDomObject>();
foreach (IDomObject obj in subSelectWithin)
{
bool match = true;
foreach (var sub in selector.SubSelectors)
{
List <IDomObject> listOfOne = new List <IDomObject>();
listOfOne.Add(obj);
bool has = !sub.Select(document, listOfOne).IsNullOrEmpty();
match &= isHasSelector == has;
}
if (match)
{
filteredResults.Add(obj);
}
}
interimResult = filteredResults;
}
tempResult = new HashSet <IDomObject>();
if (lastResult != null)
{
tempResult.AddRange(lastResult);
}
if (interimResult != null)
{
tempResult.AddRange(interimResult);
}
lastResult = tempResult;
}
if (lastResult != null)
{
output.AddRange(lastResult);
}
if (output.IsNullOrEmpty())
{
yield break;
}
else
{
// Selectors always return in DOM order. Selections may end up in a different order but
// we always sort here.
foreach (IDomObject item in output.OrderBy(item => item.Path, StringComparer.Ordinal))
{
yield return(item);
}
}
ActiveSelectors.Clear();
}
/// <summary>
/// Returns a string representation of the parsed selector. This may not exactly match the input
/// selector as it is regenerated.
/// </summary>
///
/// <returns>
/// A CSS selector string.
/// </returns>
public override string ToString()
{
string output = "";
switch (TraversalType)
{
case TraversalType.Child:
output += " > ";
break;
case TraversalType.Descendent:
output += " ";
break;
case TraversalType.Adjacent:
output += " + ";
break;
case TraversalType.Sibling:
output += " ~ ";
break;
}
if (SelectorType.HasFlag(SelectorType.Elements))
{
output += "<ElementList[" + SelectElements.Count() + "]> ";
}
if (SelectorType.HasFlag(SelectorType.HTML))
{
output += "<HTML[" + Html.Length + "]> ";
}
if (SelectorType.HasFlag(SelectorType.Tag))
{
output += Tag;
}
if (SelectorType.HasFlag(SelectorType.ID))
{
output += "#" + ID;
}
if (SelectorType.HasFlag(SelectorType.AttributeValue)
//|| SelectorType.HasFlag(SelectorType.AttributeExists)
)
{
output += "[" + AttributeName;
if (!String.IsNullOrEmpty(AttributeValue))
{
output += "." + AttributeSelectorType.ToString() + ".'" + AttributeValue + "'";
}
output += "]";
}
if (SelectorType.HasFlag(SelectorType.Class))
{
output += "." + Class;
}
if (SelectorType.HasFlag(SelectorType.All))
{
output += "*";
}
if (SelectorType.HasFlag(SelectorType.PseudoClass))
{
output += ":" + PseudoSelector.Name;
if (PseudoSelector.Arguments != null && PseudoSelector.Arguments.Length > 0)
{
output += "(" + String.Join(",", PseudoSelector.Arguments) + ")";
}
}
return(output);
}
public override string ToString()
{
string output = "";
switch (TraversalType)
{
case TraversalType.All:
output = "";
break;
case TraversalType.Child:
output += " > ";
break;
case TraversalType.Descendent:
output += " ";
break;
}
if (SelectorType.HasFlag(SelectorType.Elements))
{
output += "<ElementList[" + SelectElements.Count() + "]> ";
}
if (SelectorType.HasFlag(SelectorType.HTML))
{
output += "<HTML[" + Html.Length + "]> ";
}
if (SelectorType.HasFlag(SelectorType.Tag))
{
output += Tag;
}
if (SelectorType.HasFlag(SelectorType.ID))
{
output += "#" + ID;
}
if (SelectorType.HasFlag(SelectorType.Attribute))
{
output += "[" + AttributeName;
if (!String.IsNullOrEmpty(AttributeValue))
{
output += "." + AttributeSelectorType.ToString() + ".'" + AttributeValue + "'";
}
output += "]";
}
if (SelectorType.HasFlag(SelectorType.Class))
{
output += "." + Class;
}
if (SelectorType.HasFlag(SelectorType.All))
{
output += "*";
}
if (SelectorType.HasFlag(SelectorType.Position))
{
output += ":" + PositionType.ToString();
if (IsFunction)
{
output += "(" + PositionIndex + ")";
}
else if (SubSelectors.Count > 0)
{
output += SubSelectors.ToString();
}
}
if (SelectorType.HasFlag(SelectorType.Contains))
{
output += ":contains(" + Criteria + ")";
}
return(output);
}
