/// <summary>
/// Gets the regex that represents the given filter group
/// </summary>
/// <param name="filterGroupName">Filter group name</param>
/// <returns>Group regex</returns>
private static Regex GetFilterGroupRegex(string filterGroupName)
{
FilterGroup filterGroup = FilterGroups.ParseFilterList(filterGroupName, FilterGroup.None);
Regex result;
if (FilterEntry.filterGroupRegexCache.TryGetValue(filterGroup, out result))
{
return(result);
}
else
{
// Get the filter strings for this filter group, and convert them to their regex forms
List <string> regexStrings = FilterGroups.GetFilterStrings(filterGroup)
.Select(filterString =>
{
if (filterString.StartsWith("[", StringComparison.Ordinal) && filterString.EndsWith("]", StringComparison.Ordinal))
{
return(filterString.Substring(1, filterString.Length - 2));
}
else if (filterString.StartsWith("@", StringComparison.Ordinal))
{
return(Utility.ConvertLiteralToRegExp(filterString.Substring(1)));
}
else
{
return(Utility.ConvertGlobbingToRegExp(filterString));
}
})
.ToList();
string regexString;
if (regexStrings.Count == 1)
{
regexString = regexStrings.Single();
}
else
{
// If there are multiple regex strings, then they need to be merged by wrapping each in parenthesis and ORing them together
regexString = "(" + string.Join(")|(", regexStrings) + ")";
}
result = new Regex(regexString, REGEXP_OPTIONS);
FilterEntry.filterGroupRegexCache[filterGroup] = result;
return(result);
}
}
private static IEnumerable <string> Expand(string filter)
{
if (string.IsNullOrWhiteSpace(filter))
{
return(null);
}
if (filter.Length < 2 || (filter.StartsWith("[", StringComparison.Ordinal) && filter.EndsWith("]", StringComparison.Ordinal)))
{
return(new string[] { filter });
}
if (filter.StartsWith("{", StringComparison.Ordinal) && filter.EndsWith("}", StringComparison.Ordinal))
{
string groupName = filter.Substring(1, filter.Length - 2);
FilterGroup filterGroup = FilterGroups.ParseFilterList(groupName, FilterGroup.None);
return((filterGroup == FilterGroup.None) ? null : FilterGroups.GetFilterStrings(filterGroup));
}
return(filter.Split(new char[] { System.IO.Path.PathSeparator }, StringSplitOptions.RemoveEmptyEntries));
}
