}
)

type Mapper struct {
	*matcher.Matcher
	Map map[string]*matcher.Matcher_OnMatch
}

func newMapper(input *xds.TypedExtensionConfig) Mapper {
	m := map[string]*matcher.Matcher_OnMatch{}
	match := &matcher.Matcher{
		MatcherType: &matcher.Matcher_MatcherTree_{
			MatcherTree: &matcher.Matcher_MatcherTree{
				Input: input,
				TreeType: &matcher.Matcher_MatcherTree_ExactMatchMap{

//		c           matches character c (c != '*', '?', '\\', '[')
//		'\\' c      matches character c
//
//	character-range:
//		c           matches character c (c != '\\', '-', ']')
//		'\\' c      matches character c
//		lo '-' hi   matches character c for lo <= c <= hi
//
// Match requires pattern to match all of name, not just a substring.
// The only possible returned error is [ErrBadPattern], when pattern
// is malformed.
//

	Filters []string

	// TotalMatch will require that the all elements exactly match (eg, if I have 3 elements in the
	// check, the listener must as well). Otherwise, we only validate the assertions we provided are
	// present.
	TotalMatch bool
}

type FilterChainTest struct {
	// Match a filter chain by name
	Name string
	// Match filter chain by 'type'. This can be important since Name is currently not unique

     * being already present in that collection.
     * <p>
     * A match means that the first n lines starting at {@code startIdx} match the lines of the
     * expected deprecation warning.  If there are not n lines starting at {@code startIdx} left in
     * the list of lines, then no match is made.
     * <p>
     * As a second side-effect, the last matched deprecation warning is stored in the

			continue
		}
		match, ok := evalResult.Value().(bool)
		if !ok {
			evalErrors = append(evalErrors, fmt.Errorf("cel evaluation error: expression '%v' eval result value should be bool but got %W", compilationResult.ExpressionAccessor.GetExpression(), evalResult.Value()))
			continue
		}
		// If at least one matchCondition successfully evaluates to FALSE,
		// return early
		if !match {

		return false, err
	}
	matched := s.Label.Matches(labels)
	if matched && s.Field != nil {
		matched = matched && s.Field.Matches(fields)
	}
	return matched, nil
}

// MatchesObjectAttributes returns true if the given labels and fields
// match s.Label and s.Field.
func (s *SelectionPredicate) MatchesObjectAttributes(l labels.Set, f fields.Set) bool {
	if s.Label.Empty() && s.Field.Empty() {
		return true
	}

}

func clusterMatch(cluster *cluster.Cluster, cp *model.EnvoyFilterConfigPatchWrapper, hosts []host.Name) bool {
	cMatch := cp.Match.GetCluster()
	if cMatch == nil {
		return true
	}

	if cMatch.Name != "" {
		return cMatch.Name == cluster.Name
	}

	direction, subset, hostname, port := model.ParseSubsetKey(cluster.Name)

	hostMatches := []host.Name{hostname}

     */
    public String find(String pattern, Collection<String> items) {
        this.pattern = pattern;
        matches.clear();
        candidates.clear();

        if (items.contains(pattern)) {
            matches.add(pattern);
            return pattern;
        }

        if (pattern.length() == 0) {
            return null;
        }

     *
     * @return The match if exactly 1 match found, null if no matches or multiple matches.
     */
    public String find(String pattern, Collection<String> items) {
        this.pattern = pattern;
        matches.clear();
        candidates.clear();

        if (items.contains(pattern)) {
            matches.add(pattern);
            return pattern;
        }

        if (pattern.length() == 0) {

			// standard metadata headers
			// specified in the filter
			var match bool
			for k, v := range obj.UserDefined {
				if !stringsHasPrefixFold(k, "x-amz-meta-") && !isStandardHeader(k) {
					continue
				}
				// We only need to match x-amz-meta or standardHeaders
				if kv.Match(BatchJobKV{Key: k, Value: v}) {
					match = true
				}
			}
			if !match {
				return false