[3647] Add support for diagram style with background customization

Bug: #3647
Signed-off-by: Florian ROUËNÉ <florian.rouene@obeosoft.com>

Author: frouene

CHANGELOG.adoc

@@ -67,6 +67,7 @@ As a result, the following maven modules have been deleted: `sirius-web-sample-a
 === New Features
 
 - https://github.com/eclipse-sirius/sirius-web/issues/3748[#3748] [diagram] Store current diagram payload in `DiagramContext`
+- https://github.com/eclipse-sirius/sirius-web/issues/3647[#3647] [diagram] Add support for diagram style with background customization
 
 
 === Improvements
@@ -155,8 +156,7 @@ More existing APIs will be migrated to this new common pattern.
 - https://github.com/eclipse-sirius/sirius-web/issues/3616[#3616] [diagram] Fix potential exceptions due to duplicate keys in diagram event processing
 - https://github.com/eclipse-sirius/sirius-web/issues/3624[#3624] [diagram] Fix an issue where the header separator does not fill the entire width of the node
 - https://github.com/eclipse-sirius/sirius-web/issues/3531[#3531] [diagram] Fix unnecessary edges label re render
-- https://github.com/eclipse-sirius/sirius-web/issues/3650[#3650] [diagram] Fix potential NPE in DiagramNavigator and Node toString method
-- https://github.com/eclipse-sirius/sirius-web/issues/3649[#3649] [sirius-web] Restore support for Related elements view icons
+- https://github.com/eclipse-sirius/sirius-web/issues/3650[#3650] [diagram] Fix potential NPE in DiagramNavigator and Node toString method- https://github.com/eclipse-sirius/sirius-web/issues/3649[#3649] [sirius-web] Restore support for Related elements view icons
 - https://github.com/eclipse-sirius/sirius-web/issues/3630[#3630] [sirius-web] Restore support for the deletion of dangling representations
 - https://github.com/eclipse-sirius/sirius-web/issues/3666[#3666] [core] Enable EMF's intrinsicIDToEObjectMap for JSON resources to support languages which use modeled identifiers (e.g. SysMLv2).
 - https://github.com/eclipse-sirius/sirius-web/issues/3664[#3664] [core] The Default.svg image is no longer displayed with the new architecture.

packages/compatibility/backend/sirius-components-compatibility-emf/src/test/java/org/eclipse/sirius/components/compatibility/emf/compatibility/diagrams/TestDiagramBuilder.java

@@ -19,6 +19,7 @@
 import org.eclipse.sirius.components.diagrams.ArrowStyle;
 import org.eclipse.sirius.components.diagrams.CollapsingState;
 import org.eclipse.sirius.components.diagrams.Diagram;
+import org.eclipse.sirius.components.diagrams.DiagramStyle;
 import org.eclipse.sirius.components.diagrams.Edge;
 import org.eclipse.sirius.components.diagrams.EdgeStyle;
 import org.eclipse.sirius.components.diagrams.FreeFormLayoutStrategy;
@@ -59,6 +60,7 @@ public Diagram getDiagram(String id) {
                 .size(Size.UNDEFINED)
                 .nodes(List.of())
                 .edges(List.of())
+                .style(DiagramStyle.newDiagramStyle().background("#FAFAFA").build())
                 .build();
     }
 

packages/compatibility/backend/sirius-components-compatibility-emf/src/test/java/org/eclipse/sirius/components/compatibility/emf/compatibility/operations/CreateViewOperationHandlerTests.java

@@ -28,6 +28,7 @@
 import org.eclipse.sirius.components.compatibility.emf.modeloperations.CreateViewOperationHandler;
 import org.eclipse.sirius.components.core.api.IEditingContext;
 import org.eclipse.sirius.components.diagrams.Diagram;
+import org.eclipse.sirius.components.diagrams.DiagramStyle;
 import org.eclipse.sirius.components.diagrams.FreeFormLayoutStrategy;
 import org.eclipse.sirius.components.diagrams.INodeStyle;
 import org.eclipse.sirius.components.diagrams.InsideLabelLocation;
@@ -88,6 +89,7 @@ public void initialize() {
                 .nodeDescriptions(List.of(this.getNodeDescription(UUID.randomUUID().toString())))
                 .edgeDescriptions(List.of())
                 .dropHandler(variableManager -> new Failure(""))
+                .styleProvider(variableManager -> DiagramStyle.newDiagramStyle().build())
                 .build();
 
         Diagram diagram = Diagram.newDiagram(UUID.randomUUID().toString())
@@ -98,6 +100,7 @@ public void initialize() {
                 .size(Size.of(100, 100))
                 .nodes(new ArrayList<>())
                 .edges(List.of())
+                .style(DiagramStyle.newDiagramStyle().background("#FAFAFA").build())
                 .build();
 
         IDiagramContext diagramContext = new IDiagramContext.NoOp() {

packages/compatibility/backend/sirius-components-compatibility-emf/src/test/java/org/eclipse/sirius/components/compatibility/emf/compatibility/operations/DeleteViewOperationHandlerTests.java

@@ -28,6 +28,7 @@
 import org.eclipse.sirius.components.core.api.IEditingContext;
 import org.eclipse.sirius.components.diagrams.CollapsingState;
 import org.eclipse.sirius.components.diagrams.Diagram;
+import org.eclipse.sirius.components.diagrams.DiagramStyle;
 import org.eclipse.sirius.components.diagrams.FreeFormLayoutStrategy;
 import org.eclipse.sirius.components.diagrams.INodeStyle;
 import org.eclipse.sirius.components.diagrams.ImageNodeStyle;
@@ -91,6 +92,7 @@ public void initialize() {
                 .nodeDescriptions(List.of(this.getNodeDescription(UUID.randomUUID().toString())))
                 .edgeDescriptions(List.of())
                 .dropHandler(variableManager -> new Failure(""))
+                .styleProvider(variableManager -> DiagramStyle.newDiagramStyle().build())
                 .build();
 
         Node node = Node.newNode(UUID.randomUUID().toString())
@@ -135,6 +137,7 @@ public void initialize() {
                 .size(Size.of(100, 100))
                 .nodes(List.of(node))
                 .edges(List.of())
+                .style(DiagramStyle.newDiagramStyle().background("#FAFAFA").build())
                 .build();
 
         IDiagramContext diagramContext = new IDiagramContext.NoOp() {

packages/compatibility/backend/sirius-components-compatibility/src/main/java/org/eclipse/sirius/components/compatibility/services/diagrams/DiagramDescriptionConverter.java

@@ -24,6 +24,7 @@
 import org.eclipse.sirius.components.compatibility.diagrams.DiagramLabelProvider;
 import org.eclipse.sirius.components.compatibility.services.diagrams.api.IDiagramDescriptionConverter;
 import org.eclipse.sirius.components.diagrams.ArrangeLayoutDirection;
+import org.eclipse.sirius.components.diagrams.DiagramStyle;
 import org.eclipse.sirius.components.diagrams.description.DiagramDescription;
 import org.eclipse.sirius.components.diagrams.description.DiagramDescription.Builder;
 import org.eclipse.sirius.components.interpreter.AQLInterpreter;
@@ -41,6 +42,8 @@ public class DiagramDescriptionConverter implements IDiagramDescriptionConverter
 
     private static final String FORCE_AUTO_LAYOUT = "FORCE_AUTO_LAYOUT";
 
+    private static final String DEFAULT_BACKGROUND_COLOR = "transparent";
+
     private final List<IDiagramDescriptionPopulator> diagramDescriptionPopulators;
 
     private final IAQLInterpreterFactory interpreterFactory;
@@ -67,7 +70,8 @@ public DiagramDescription convert(org.eclipse.sirius.diagram.description.Diagram
                 .canCreatePredicate(canCreatePredicate)
                 .labelProvider(labelProvider)
                 .autoLayout(this.isAutoLayoutMode(siriusDiagramDescription))
-                .arrangeLayoutDirection(ArrangeLayoutDirection.UNDEFINED);
+                .arrangeLayoutDirection(ArrangeLayoutDirection.UNDEFINED)
+                .styleProvider(variableManager -> DiagramStyle.newDiagramStyle().background(DEFAULT_BACKGROUND_COLOR).build());
 
         for (IDiagramDescriptionPopulator diagramDescriptionPopulator : this.diagramDescriptionPopulators) {
             diagramDescriptionPopulator.populate(builder, siriusDiagramDescription, interpreter);

packages/diagrams/backend/sirius-components-collaborative-diagrams/src/main/java/org/eclipse/sirius/components/collaborative/diagrams/DiagramServices.java

@@ -109,4 +109,10 @@ public boolean isFaded(IDiagramElement diagramElement) {
         }
         return isFaded;
     }
+
+    @Override
+    public boolean isDiagramEmpty(IDiagramService diagramService) {
+        return diagramService.getDiagramContext().getDiagram().getNodes().isEmpty() && diagramService.getDiagramContext().getViewCreationRequests().isEmpty() ||
+                diagramService.getDiagramContext().getDiagram().getNodes().size() == 1 && !diagramService.getDiagramContext().getViewDeletionRequests().isEmpty();
+    }
 }

packages/diagrams/backend/sirius-components-collaborative-diagrams/src/main/java/org/eclipse/sirius/components/collaborative/diagrams/api/IDiagramServices.java

@@ -41,4 +41,6 @@ public interface IDiagramServices {
     boolean isHidden(IDiagramElement diagramElement);
 
     boolean isFaded(IDiagramElement diagramElement);
+
+    boolean isDiagramEmpty(IDiagramService diagramService);
 }

packages/diagrams/backend/sirius-components-collaborative-diagrams/src/main/resources/schema/diagram.graphqls

@@ -35,9 +35,14 @@ type Diagram implements Representation {
   position: Position!
   nodes: [Node!]!
   edges: [Edge!]!
+  style: DiagramStyle!
   layoutData: DiagramLayoutData!
 }
 
+type DiagramStyle {
+  background: String
+}
+
 type DiagramLayoutData {
   nodeLayoutData: [NodeLayoutData!]!
 }

packages/diagrams/backend/sirius-components-collaborative-diagrams/src/test/java/org/eclipse/sirius/components/collaborative/diagrams/DiagramEventProcessorTests.java

@@ -31,6 +31,7 @@
 import org.eclipse.sirius.components.core.api.IPayload;
 import org.eclipse.sirius.components.core.api.IRepresentationDescriptionSearchService;
 import org.eclipse.sirius.components.diagrams.Diagram;
+import org.eclipse.sirius.components.diagrams.DiagramStyle;
 import org.eclipse.sirius.components.diagrams.Position;
 import org.eclipse.sirius.components.diagrams.Size;
 import org.junit.jupiter.api.Test;
@@ -56,6 +57,7 @@ public class DiagramEventProcessorTests {
             .size(Size.UNDEFINED)
             .nodes(List.of())
             .edges(List.of())
+            .style(DiagramStyle.newDiagramStyle().background("#FAFAFA").build())
             .build();
 
     private final IDiagramCreationService diagramCreationService = new MockDiagramCreationService(INITIAL_TEST_DIAGRAM);

packages/diagrams/backend/sirius-components-collaborative-diagrams/src/test/java/org/eclipse/sirius/components/collaborative/diagrams/handlers/CreateDiagramEventHandlerTests.java

@@ -32,6 +32,7 @@
 import org.eclipse.sirius.components.core.api.IPayload;
 import org.eclipse.sirius.components.core.api.IRepresentationDescriptionSearchService;
 import org.eclipse.sirius.components.diagrams.Diagram;
+import org.eclipse.sirius.components.diagrams.DiagramStyle;
 import org.eclipse.sirius.components.diagrams.description.DiagramDescription;
 import org.eclipse.sirius.components.representations.Failure;
 import org.eclipse.sirius.components.representations.IRepresentationDescription;
@@ -64,6 +65,7 @@ public Optional<IRepresentationDescription> findById(IEditingContext editingCont
                         .nodeDescriptions(new ArrayList<>())
                         .targetObjectIdProvider(variableManager -> "targetObjectId")
                         .dropHandler(variableManager -> new Failure(""))
+                        .styleProvider(variableManager -> DiagramStyle.newDiagramStyle().build())
                         .build();
                 // @formatter:on