[misc] Separate shared code dependencies (#4288)

* Separate shared code dependencies

* Fix import

* Test respective shared code

* Update openapi ref

* Fix test

* Fix test path

shared/relay/messages/peer_state_test.go

@@ -0,0 +1,144 @@
+package messages
+
+import (
+	"bytes"
+	"testing"
+)
+
+const (
+	testPeerCount = 10
+)
+
+// Helper function to generate test PeerIDs
+func generateTestPeerIDs(n int) []PeerID {
+	ids := make([]PeerID, n)
+	for i := 0; i < n; i++ {
+		for j := 0; j < peerIDSize; j++ {
+			ids[i][j] = byte(i + j)
+		}
+	}
+	return ids
+}
+
+// Helper function to compare slices of PeerID
+func peerIDEqual(a, b []PeerID) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i := range a {
+		if !bytes.Equal(a[i][:], b[i][:]) {
+			return false
+		}
+	}
+	return true
+}
+
+func TestMarshalUnmarshalSubPeerState(t *testing.T) {
+	ids := generateTestPeerIDs(testPeerCount)
+
+	msgs, err := MarshalSubPeerStateMsg(ids)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	var allIDs []PeerID
+	for _, msg := range msgs {
+		decoded, err := UnmarshalSubPeerStateMsg(msg)
+		if err != nil {
+			t.Fatalf("unmarshal failed: %v", err)
+		}
+		allIDs = append(allIDs, decoded...)
+	}
+
+	if !peerIDEqual(ids, allIDs) {
+		t.Errorf("expected %v, got %v", ids, allIDs)
+	}
+}
+
+func TestMarshalSubPeerState_EmptyInput(t *testing.T) {
+	_, err := MarshalSubPeerStateMsg([]PeerID{})
+	if err == nil {
+		t.Errorf("expected error for empty input")
+	}
+}
+
+func TestUnmarshalSubPeerState_Invalid(t *testing.T) {
+	// Too short
+	_, err := UnmarshalSubPeerStateMsg([]byte{1})
+	if err == nil {
+		t.Errorf("expected error for short input")
+	}
+
+	// Misaligned length
+	buf := make([]byte, sizeOfProtoHeader+1)
+	_, err = UnmarshalSubPeerStateMsg(buf)
+	if err == nil {
+		t.Errorf("expected error for misaligned input")
+	}
+}
+
+func TestMarshalUnmarshalPeersOnline(t *testing.T) {
+	ids := generateTestPeerIDs(testPeerCount)
+
+	msgs, err := MarshalPeersOnline(ids)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	var allIDs []PeerID
+	for _, msg := range msgs {
+		decoded, err := UnmarshalPeersOnlineMsg(msg)
+		if err != nil {
+			t.Fatalf("unmarshal failed: %v", err)
+		}
+		allIDs = append(allIDs, decoded...)
+	}
+
+	if !peerIDEqual(ids, allIDs) {
+		t.Errorf("expected %v, got %v", ids, allIDs)
+	}
+}
+
+func TestMarshalPeersOnline_EmptyInput(t *testing.T) {
+	_, err := MarshalPeersOnline([]PeerID{})
+	if err == nil {
+		t.Errorf("expected error for empty input")
+	}
+}
+
+func TestUnmarshalPeersOnline_Invalid(t *testing.T) {
+	_, err := UnmarshalPeersOnlineMsg([]byte{1})
+	if err == nil {
+		t.Errorf("expected error for short input")
+	}
+}
+
+func TestMarshalUnmarshalPeersWentOffline(t *testing.T) {
+	ids := generateTestPeerIDs(testPeerCount)
+
+	msgs, err := MarshalPeersWentOffline(ids)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	var allIDs []PeerID
+	for _, msg := range msgs {
+		// MarshalPeersWentOffline shares no unmarshal function, so reuse PeersOnline
+		decoded, err := UnmarshalPeersOnlineMsg(msg)
+		if err != nil {
+			t.Fatalf("unmarshal failed: %v", err)
+		}
+		allIDs = append(allIDs, decoded...)
+	}
+
+	if !peerIDEqual(ids, allIDs) {
+		t.Errorf("expected %v, got %v", ids, allIDs)
+	}
+}
+
+func TestMarshalPeersWentOffline_EmptyInput(t *testing.T) {
+	_, err := MarshalPeersWentOffline([]PeerID{})
+	if err == nil {
+		t.Errorf("expected error for empty input")
+	}
+}