Adding upstream version 0.0~git20250501.71edba4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

flatten.go

@@ -0,0 +1,142 @@
+package activitypub
+
+// FlattenActivityProperties flattens the Activity's properties from Object type to IRI
+func FlattenActivityProperties(act *Activity) *Activity {
+	if act == nil {
+		return nil
+	}
+	_ = OnIntransitiveActivity(act, func(in *IntransitiveActivity) error {
+		FlattenIntransitiveActivityProperties(in)
+		return nil
+	})
+	act.Object = FlattenToIRI(act.Object)
+	return act
+}
+
+// FlattenIntransitiveActivityProperties flattens the Activity's properties from Object type to IRI
+func FlattenIntransitiveActivityProperties(act *IntransitiveActivity) *IntransitiveActivity {
+	if act == nil {
+		return nil
+	}
+	act.Actor = FlattenToIRI(act.Actor)
+	act.Target = FlattenToIRI(act.Target)
+	act.Result = FlattenToIRI(act.Result)
+	act.Origin = FlattenToIRI(act.Origin)
+	act.Result = FlattenToIRI(act.Result)
+	act.Instrument = FlattenToIRI(act.Instrument)
+	_ = OnObject(act, func(o *Object) error {
+		FlattenObjectProperties(o)
+		return nil
+	})
+	return act
+}
+
+// FlattenItemCollection flattens an Item Collection to their respective IRIs
+func FlattenItemCollection(col ItemCollection) ItemCollection {
+	if col == nil {
+		return col
+	}
+	for k, it := range ItemCollectionDeduplication(&col) {
+		if iri := it.GetLink(); iri != "" {
+			col[k] = iri
+		}
+	}
+	return col
+}
+
+// FlattenCollection flattens a Collection's objects to their respective IRIs
+func FlattenCollection(col *Collection) *Collection {
+	if col == nil {
+		return col
+	}
+	col.Items = FlattenItemCollection(col.Items)
+
+	return col
+}
+
+// FlattenOrderedCollection flattens an OrderedCollection's objects to their respective IRIs
+func FlattenOrderedCollection(col *OrderedCollection) *OrderedCollection {
+	if col == nil {
+		return col
+	}
+	col.OrderedItems = FlattenItemCollection(col.OrderedItems)
+
+	return col
+}
+
+// FlattenActorProperties flattens the Actor's properties from Object types to IRI
+func FlattenActorProperties(a *Actor) *Actor {
+	if a == nil {
+		return nil
+	}
+	OnObject(a, func(o *Object) error {
+		FlattenObjectProperties(o)
+		return nil
+	})
+	return a
+}
+
+// FlattenObjectProperties flattens the Object's properties from Object types to IRI
+func FlattenObjectProperties(o *Object) *Object {
+	if o == nil {
+		return nil
+	}
+	o.Replies = Flatten(o.Replies)
+	o.Shares = Flatten(o.Shares)
+	o.Likes = Flatten(o.Likes)
+	o.AttributedTo = Flatten(o.AttributedTo)
+	o.To = FlattenItemCollection(o.To)
+	o.Bto = FlattenItemCollection(o.Bto)
+	o.CC = FlattenItemCollection(o.CC)
+	o.BCC = FlattenItemCollection(o.BCC)
+	o.Audience = FlattenItemCollection(o.Audience)
+	// o.Tag = FlattenItemCollection(o.Tag)
+	return o
+}
+
+// FlattenProperties flattens the Item's properties from Object types to IRI
+func FlattenProperties(it Item) Item {
+	if IsNil(it) {
+		return nil
+	}
+	typ := it.GetType()
+	if IntransitiveActivityTypes.Contains(typ) {
+		_ = OnIntransitiveActivity(it, func(a *IntransitiveActivity) error {
+			FlattenIntransitiveActivityProperties(a)
+			return nil
+		})
+	} else if ActivityTypes.Contains(typ) {
+		_ = OnActivity(it, func(a *Activity) error {
+			FlattenActivityProperties(a)
+			return nil
+		})
+	}
+	if ActorTypes.Contains(typ) {
+		OnActor(it, func(a *Actor) error {
+			FlattenActorProperties(a)
+			return nil
+		})
+	}
+	if ObjectTypes.Contains(typ) {
+		OnObject(it, func(o *Object) error {
+			FlattenObjectProperties(o)
+			return nil
+		})
+	}
+	return it
+}
+
+// Flatten checks if Item can be flattened to an IRI or array of IRIs and returns it if so
+func Flatten(it Item) Item {
+	if IsNil(it) {
+		return nil
+	}
+	if it.IsCollection() {
+		OnCollectionIntf(it, func(c CollectionInterface) error {
+			it = FlattenItemCollection(c.Collection()).Normalize()
+			return nil
+		})
+		return it
+	}
+	return it.GetLink()
+}