feat(waiting-room): choose relations when associated endpoint [EE-5187] (#8720)

api/internal/set/set.go

@@ -6,27 +6,33 @@ type SetKey interface {
 
 type Set[T SetKey] map[T]bool
 
+// Add adds a key to the set.
 func (s Set[T]) Add(key T) {
 	s[key] = true
 }
 
+// Contains returns true if the set contains the key.
 func (s Set[T]) Contains(key T) bool {
 	_, ok := s[key]
 	return ok
 }
 
+// Remove removes a key from the set.
 func (s Set[T]) Remove(key T) {
 	delete(s, key)
 }
 
+// Len returns the number of keys in the set.
 func (s Set[T]) Len() int {
 	return len(s)
 }
 
+// IsEmpty returns true if the set is empty.
 func (s Set[T]) IsEmpty() bool {
 	return len(s) == 0
 }
 
+// Clear removes all keys from the set.
 func (s Set[T]) Keys() []T {
 	keys := make([]T, s.Len())
 
@@ -38,3 +44,67 @@ func (s Set[T]) Keys() []T {
 
 	return keys
 }
+
+// Clear removes all keys from the set.
+func (s Set[T]) Copy() Set[T] {
+	copy := make(Set[T])
+
+	for key := range s {
+		copy.Add(key)
+	}
+
+	return copy
+}
+
+// Difference returns a new set containing the keys that are in the first set but not in the second set.
+func (set Set[T]) Difference(second Set[T]) Set[T] {
+
+	difference := set.Copy()
+
+	for key := range second {
+		difference.Remove(key)
+	}
+
+	return difference
+}
+
+// Union returns a new set containing the keys that are in either set.
+func Union[T SetKey](sets ...Set[T]) Set[T] {
+	union := make(Set[T])
+
+	for _, set := range sets {
+		for key := range set {
+			union.Add(key)
+		}
+	}
+
+	return union
+}
+
+// Intersection returns a new set containing the keys that are in all sets.
+func Intersection[T SetKey](sets ...Set[T]) Set[T] {
+	if len(sets) == 0 {
+		return make(Set[T])
+	}
+
+	intersection := sets[0].Copy()
+
+	for _, set := range sets[1:] {
+		for key := range intersection {
+			if !set.Contains(key) {
+				intersection.Remove(key)
+			}
+		}
+	}
+
+	return intersection
+}
+
+// ToSet returns a new set containing the keys.
+func ToSet[T SetKey](keys []T) Set[T] {
+	set := make(Set[T])
+	for _, key := range keys {
+		set.Add(key)
+	}
+	return set
+}