1 files changed, 291 insertions, 0 deletions
diff --git a/plugins/infra/org.eclipse.papyrus.infra.ui/src/org/eclipse/papyrus/infra/ui/editor/MultiDiagramEditorSelectionContext.java b/plugins/infra/org.eclipse.papyrus.infra.ui/src/org/eclipse/papyrus/infra/ui/editor/MultiDiagramEditorSelectionContext.java
new file mode 100644
index 00000000000..fc0302004dd
--- /dev/null
+++ b/plugins/infra/org.eclipse.papyrus.infra.ui/src/org/eclipse/papyrus/infra/ui/editor/MultiDiagramEditorSelectionContext.java
@@ -0,0 +1,291 @@
+/*
+ * Copyright (c) 2014 CEA and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *   Christian W. Damus (CEA) - Initial API and implementation
+ *
+ */
+package org.eclipse.papyrus.infra.ui.editor;
+
+import java.util.List;
+import java.util.Set;
+
+import org.eclipse.emf.common.util.URI;
+import org.eclipse.emf.ecore.resource.Resource;
+import org.eclipse.emf.ecore.resource.ResourceSet;
+import org.eclipse.emf.edit.domain.EditingDomain;
+import org.eclipse.jface.viewers.ISelection;
+import org.eclipse.jface.viewers.ISelectionChangedListener;
+import org.eclipse.jface.viewers.ISelectionProvider;
+import org.eclipse.jface.viewers.IStructuredSelection;
+import org.eclipse.jface.viewers.StructuredSelection;
+import org.eclipse.papyrus.infra.core.sasheditor.editor.IComponentPage;
+import org.eclipse.papyrus.infra.core.sasheditor.editor.IEditorPage;
+import org.eclipse.papyrus.infra.core.sasheditor.editor.IPage;
+import org.eclipse.papyrus.infra.core.sasheditor.editor.IPageVisitor;
+import org.eclipse.papyrus.infra.core.sasheditor.editor.ISashWindowsContainer;
+import org.eclipse.papyrus.infra.core.utils.AdapterUtils;
+import org.eclipse.papyrus.infra.ui.Activator;
+import org.eclipse.papyrus.infra.ui.editor.reload.CompositeReloadContext;
+import org.eclipse.papyrus.infra.ui.editor.reload.DelegatingReloadContext;
+import org.eclipse.papyrus.infra.ui.editor.reload.EMFSelectionContext;
+import org.eclipse.papyrus.infra.ui.editor.reload.EditorReloadEvent;
+
+import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
+
+
+/**
+ * A {@linkplain EditorReloadEvent reload event} context that restores the selection of which editor page
+ * is active in an {@link IMultiDiagramEditor} that is reloaded and delegates to its pages to capture
+ * re-load context for each to restore whatever they need to restore (internal selections etc.).
+ */
+class MultiDiagramEditorSelectionContext extends CompositeReloadContext {
+
+	private ISashWindowsContainer sashContainer;
+
+	private final List<URI> resourcesToLoad;
+
+	MultiDiagramEditorSelectionContext(IMultiDiagramEditor editor) {
+		super();
+
+		init(editor);
+
+		resourcesToLoad = computeResourcesToLoad(editor);
+
+		IPage active = sashContainer.getActiveSashWindowsPage();
+		DiagramPageContext activePage = null;
+
+		Set<IPage> visiblePages = Sets.newIdentityHashSet();
+		visiblePages.addAll(sashContainer.getVisiblePages());
+
+		List<IPage> allPages = getAllPages(sashContainer);
+
+		for (IPage page : allPages) {
+			final DelegatingReloadContext delegator = (page instanceof IEditorPage) ? add(new DelegatingReloadContext(((IEditorPage) page).getIEditorPart())) : null;
+			DiagramPageContext context;
+
+			if (page == active) {
+				// This one will have the selection of the active page
+				context = new DiagramPageContext(new VisiblePageSelectionProvider(page), page, delegator);
+				activePage = context;
+			} else {
+				if (visiblePages.contains(page)) {
+					// This one must be selected in its folder in order to make it visible again
+					context = new DiagramPageContext(new VisiblePageSelectionProvider(page), page, delegator);
+				} else {
+					context = new DiagramPageContext(EmptySelectionProvider.INSTANCE, page, delegator);
+				}
+
+				// We make sure always to restore the active page last
+				// so that it will not only be visible but also the
+				// over-all active page
+				add(context);
+			}
+		}
+
+		if (activePage != null) {
+			// Restore this one last
+			add(activePage);
+		}
+	}
+
+	@Override
+	public void dispose() {
+		sashContainer = null;
+		super.dispose();
+	}
+
+	private List<IPage> getAllPages(ISashWindowsContainer container) {
+		final List<IPage> result = Lists.newArrayList();
+
+		container.visit(new IPageVisitor() {
+
+			@Override
+			public void accept(IEditorPage page) {
+				result.add(page);
+			}
+
+			@Override
+			public void accept(IComponentPage page) {
+				result.add(page);
+			}
+		});
+
+		return result;
+	}
+
+	private void init(IMultiDiagramEditor editor) {
+		sashContainer = AdapterUtils.adapt(editor, ISashWindowsContainer.class, null);
+	}
+
+	void restore(IMultiDiagramEditor editor) {
+		init(editor);
+
+		// Forcibly re-load all previously loaded resources to that
+		// (a) we don't lose imports that weren't yet used, and
+		// (b) we can restore selections in resources that wouldn't be loaded until proxies resolve later
+		reloadResources(editor);
+
+		ISelectionProvider selectionProvider = new VisiblePageSelectionProvider();
+		for (DiagramPageContext next : getReloadContexts(DiagramPageContext.class)) {
+			next.restore(selectionProvider);
+		}
+	}
+
+	protected List<URI> computeResourcesToLoad(IMultiDiagramEditor editor) {
+		List<URI> result = null;
+
+		ResourceSet rset = getResourceSet(editor);
+		if (rset != null) {
+			result = Lists.newArrayListWithCapacity(rset.getResources().size());
+
+			for (Resource next : rset.getResources()) {
+				if (next.isLoaded()) {
+					result.add(next.getURI());
+				}
+			}
+		}
+
+		return result;
+	}
+
+	protected void reloadResources(IMultiDiagramEditor editor) {
+		if (resourcesToLoad != null) {
+			ResourceSet rset = getResourceSet(editor);
+			if (rset != null) {
+				for (URI next : resourcesToLoad) {
+					try {
+						rset.getResource(next, true);
+					} catch (Exception e) {
+						Activator.log.error("Failed to restore loaded resource: " + next, e); //$NON-NLS-1$
+					}
+				}
+			}
+		}
+	}
+
+	protected final ResourceSet getResourceSet(IMultiDiagramEditor editor) {
+		ResourceSet result = null;
+
+		EditingDomain editingDomain = editor.getAdapter(EditingDomain.class);
+		if (editingDomain != null) {
+			result = editingDomain.getResourceSet();
+		}
+
+		return result;
+	}
+
+	//
+	// Nested types
+	//
+
+	private class DiagramPageContext extends EMFSelectionContext {
+
+		private URI pageRef;
+
+		private DelegatingReloadContext pageContext;
+
+		DiagramPageContext(ISelectionProvider structuredSelectionProvider, IPage page, DelegatingReloadContext pageContext) {
+			super(structuredSelectionProvider);
+
+			this.pageContext = pageContext;
+			this.pageRef = getToken(page.getRawModel());
+		}
+
+		@Override
+		public void restore(ISelectionProvider structuredSelectionProvider) {
+			IPage page = sashContainer.lookupModelPage(resolveToken(pageRef));
+
+			if ((pageContext != null) && (page instanceof IEditorPage)) {
+				pageContext.restore(((IEditorPage) page).getIEditorPart());
+			}
+
+			super.restore(structuredSelectionProvider);
+		}
+
+		@Override
+		protected Object deresolveSelectableElement(Object selectableElement) {
+			return (selectableElement instanceof IPage) ? ((IPage) selectableElement).getRawModel() : super.deresolveSelectableElement(selectableElement);
+		}
+
+		@Override
+		protected Object resolveSelectableElement(Object deresolved) {
+			return sashContainer.lookupModelPage(deresolved);
+		}
+	}
+
+	private static class EmptySelectionProvider implements ISelectionProvider {
+
+		static final EmptySelectionProvider INSTANCE = new EmptySelectionProvider();
+
+		EmptySelectionProvider() {
+			super();
+		}
+
+		@Override
+		public ISelection getSelection() {
+			return StructuredSelection.EMPTY;
+		}
+
+		@Override
+		public void setSelection(ISelection selection) {
+			// Pass
+		}
+
+		@Override
+		public void addSelectionChangedListener(ISelectionChangedListener listener) {
+			// Not needed because the selection is always empty
+		}
+
+		@Override
+		public void removeSelectionChangedListener(ISelectionChangedListener listener) {
+			// Not needed because the selection is always empty
+		}
+
+	}
+
+	private class VisiblePageSelectionProvider implements ISelectionProvider {
+
+		private final IStructuredSelection selection;
+
+		VisiblePageSelectionProvider() {
+			this(null);
+		}
+
+		VisiblePageSelectionProvider(IPage visible) {
+			super();
+
+			this.selection = (visible == null) ? StructuredSelection.EMPTY : new StructuredSelection(visible);
+		}
+
+		@Override
+		public ISelection getSelection() {
+			return selection;
+		}
+
+		@Override
+		public void setSelection(ISelection selection) {
+			if (!selection.isEmpty()) {
+				IPage page = (IPage) ((IStructuredSelection) selection).getFirstElement();
+				sashContainer.selectPage(page);
+			}
+		}
+
+		@Override
+		public void addSelectionChangedListener(ISelectionChangedListener listener) {
+			// Not needed
+		}
+
+		@Override
+		public void removeSelectionChangedListener(ISelectionChangedListener listener) {
+			// Not needed
+		}
+
+	}
+}