Allow signature requests only on current published version

Requesting a signature only validated that the version was PUBLISHED, so a
signature could be requested on a superseded (older) published version. Reject
versions that are not the document's current published major/minor, and hide
the request button in the console for non-current versions.

Signed-off-by: Sacha Al Himdani <sacha@probo.com>

pkg/probo/document_service.go

@@ -68,6 +68,9 @@ type (
 	ErrDocumentVersionNotPublished struct {
 	}
 
+	ErrDocumentVersionNotCurrent struct {
+	}
+
 	ErrDocumentVersionPendingApproval struct {
 	}
 
@@ -270,6 +273,10 @@ func (e ErrDocumentVersionNotPublished) Error() string {
 	return "document version is not published"
 }
 
+func (e ErrDocumentVersionNotCurrent) Error() string {
+	return "document version is not the current published version"
+}
+
 func (e ErrDocumentVersionPendingApproval) Error() string {
 	return "cannot publish a document version that is pending approval"
 }
@@ -1104,6 +1111,13 @@ func (s *DocumentService) RequestSignature(
 				return &ErrDocumentVersionNotPublished{}
 			}
 
+			if document.CurrentPublishedMajor == nil ||
+				document.CurrentPublishedMinor == nil ||
+				documentVersion.Major != *document.CurrentPublishedMajor ||
+				documentVersion.Minor != *document.CurrentPublishedMinor {
+				return &ErrDocumentVersionNotCurrent{}
+			}
+
 			profile := &coredata.MembershipProfile{}
 			if err := profile.LoadByID(ctx, tx, scope, req.Signatory); err != nil {
 				return fmt.Errorf("cannot load signatory profile: %w", err)

pkg/server/api/console/v1/document_resolvers.go

@@ -1337,6 +1337,10 @@ func (r *mutationResolver) RequestSignature(ctx context.Context, input types.Req
 			return nil, gqlutils.Conflict(ctx, errNotPublished)
 		}
 
+		if errNotCurrent, ok := errors.AsType[*probo.ErrDocumentVersionNotCurrent](err); ok {
+			return nil, gqlutils.Conflict(ctx, errNotCurrent)
+		}
+
 		if errContractEnded, ok := errors.AsType[*probo.ErrProfileContractEnded](err); ok {
 			return nil, gqlutils.Conflict(ctx, errContractEnded)
 		}

pkg/server/api/mcp/v1/schema.resolvers.go

@@ -2456,6 +2456,10 @@ func (r *Resolver) RequestDocumentVersionSignatureTool(ctx context.Context, req
 		},
 	)
 	if err != nil {
+		if _, ok := errors.AsType[*probo.ErrDocumentVersionNotCurrent](err); ok {
+			return nil, types.RequestDocumentVersionSignatureOutput{}, fmt.Errorf("cannot request signature: %w", err)
+		}
+
 		panic(fmt.Errorf("cannot request signature: %w", err))
 	}