feat: initial recursive archive cataloging impl

Signed-off-by: Keith Zantow <keith.zantow@anchore.com>

internal/index/prefix_suffix.go

@@ -0,0 +1,37 @@
+package index
+
+// PrefixSuffix index combines two KeySplitIndexes to simplify indexing and searching by prefix and suffix
+type PrefixSuffix[T any] struct {
+	forwardIndex KeySplitIndex[T]
+	reverseIndex KeySplitIndex[T]
+}
+
+func (f *PrefixSuffix[T]) Set(key string, value T) {
+	f.forwardIndex.Set(key, value)
+	f.reverseIndex.Set(reverse(key), value)
+}
+
+func (f *PrefixSuffix[T]) Update(key string, fn NodeUpdateFunc[T]) {
+	f.forwardIndex.Update(key, fn)
+	f.reverseIndex.Update(reverse(key), fn)
+}
+
+func (f *PrefixSuffix[T]) Get(key string) T {
+	return f.forwardIndex.Get(key)
+}
+
+func (f *PrefixSuffix[T]) ByPrefix(prefix string) []T {
+	return f.forwardIndex.ByPrefix(prefix)
+}
+
+func (f *PrefixSuffix[T]) BySuffix(suffix string) []T {
+	return f.reverseIndex.ByPrefix(reverse(suffix))
+}
+
+func reverse(s string) string {
+	runes := []rune(s)
+	for i, j := 0, len(runes)-1; i < j; i, j = i+1, j-1 {
+		runes[i], runes[j] = runes[j], runes[i]
+	}
+	return string(runes)
+}