private HighlightJobCollection ApplyDescriptors(string text, int indexOfTextArgInSourceCode, IList <SyntaxHighlightDescriptor> descriptors)
{
var jobs = new HighlightJobCollection();
foreach (var descriptor in descriptors)
{
CancellationToken?.ThrowIfCancellationRequested();
ApplyDescriptor(text, indexOfTextArgInSourceCode, descriptor, jobs);
}
return(jobs);
}
private void ApplyDescriptor(string text, int indexOfTextArgInSourceCode, SyntaxHighlightDescriptor descriptor, HighlightJobCollection jobs)
{
if (descriptor.Pattern == null)
{
var job = new HighlightJob(descriptor.ColorKey, indexOfTextArgInSourceCode, text.Length);
jobs.TryInsert(job);
return;
}
var matches = descriptor.Pattern.Matches(text);
if (matches.Count == 0)
{
return;
}
foreach (Match match in matches)
{
CancellationToken?.ThrowIfCancellationRequested();
var job = new HighlightJob(descriptor.ColorKey, indexOfTextArgInSourceCode + match.Index, match.Length);
var insertionPoint = jobs.GetInsertionPoint(job);
var processChildDescriptors = (insertionPoint >= 0) && (descriptor.CapturedGroups != null);
if (processChildDescriptors)
{
// because regex groups can't overlap, we do not require the added constraint provided by HighlightJobCollection.
// A simple List<HighlightJob> is sufficient
var childJobs = new List <HighlightJob>();
for (var i = 1; i < match.Groups.Count; ++i)
{
if (descriptor.CapturedGroups.TryGetValue(i, out var childDescriptors))
{
childJobs.AddRange(ApplyDescriptors(match.Groups[i].Value, indexOfTextArgInSourceCode + match.Groups[i].Index, childDescriptors));
}
}
job.ChildJobs = childJobs;
}
// A job without a color key leaves its portion of text up for grabs by other jobs.
// The portion of its text used by its child jobs (if any) are not available to other jobs
if (!string.IsNullOrEmpty(job.ColorKey) && insertionPoint >= 0)
{
jobs.Insert(insertionPoint, job);
}
else if (processChildDescriptors)
{
jobs.AddJobs(job.ChildJobs);
}
}
}
