Base for constraint verifiers

refs 2334

org.fortiss.tooling.kernel.ui/trunk/src/org/fortiss/tooling/kernel/ui/extension/base/ConstraintVerifierUIBase.java

+/*--------------------------------------------------------------------------+
+$Id$
+|                                                                          |
+| Copyright 2015 ForTISS GmbH                     |
+|                                                                          |
+| Licensed under the Apache License, Version 2.0 (the "License");          |
+| you may not use this file except in compliance with the License.         |
+| You may obtain a copy of the License at                                  |
+|                                                                          |
+|    http://www.apache.org/licenses/LICENSE-2.0                            |
+|                                                                          |
+| Unless required by applicable law or agreed to in writing, software      |
+| distributed under the License is distributed on an "AS IS" BASIS,        |
+| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
+| See the License for the specific language governing permissions and      |
+| limitations under the License.                                           |
++--------------------------------------------------------------------------*/
+package org.fortiss.tooling.kernel.ui.extension.base;
+
+import java.util.List;
+
+import org.eclipse.jface.dialogs.MessageDialog;
+import org.eclipse.swt.SWT;
+import org.eclipse.swt.events.SelectionAdapter;
+import org.eclipse.swt.events.SelectionEvent;
+import org.eclipse.swt.layout.GridData;
+import org.eclipse.swt.layout.GridLayout;
+import org.eclipse.swt.widgets.Button;
+import org.eclipse.swt.widgets.Composite;
+import org.eclipse.swt.widgets.Control;
+import org.eclipse.swt.widgets.Display;
+import org.eclipse.swt.widgets.Group;
+import org.eclipse.swt.widgets.Shell;
+import org.fortiss.tooling.kernel.model.constraints.ErrorVerificationStatus;
+import org.fortiss.tooling.kernel.model.constraints.FailVerificationStatus;
+import org.fortiss.tooling.kernel.model.constraints.IConstraint;
+import org.fortiss.tooling.kernel.model.constraints.IConstraintVerificationStatus;
+import org.fortiss.tooling.kernel.model.constraints.OutdatedVerificationStatus;
+import org.fortiss.tooling.kernel.service.IConstraintVerificationService;
+import org.fortiss.tooling.kernel.service.IConstraintVerificationService.IFix;
+import org.fortiss.tooling.kernel.ui.extension.IConstraintVerifierUI;
+
+/**
+ * Base class for constraint verification GUI.
+ * 
+ * @author vincent
+ * @author $Author$
+ * @version $Rev$
+ * @ConQAT.Rating YELLOW Hash: 3FA7D98F2CAEDA4B41362486FCA29373
+ */
+public class ConstraintVerifierUIBase<T extends IConstraint> implements IConstraintVerifierUI<T> {
+
+	/** {@inheritDoc} */
+	@Override
+	public boolean openStatus(IConstraintVerificationStatus status) {
+		if(!canOpen(status)) {
+			return false;
+		}
+		if(status instanceof OutdatedVerificationStatus) {
+			IConstraint constraint = status.getConstraint();
+			IConstraintVerificationService.INSTANCE.verify(constraint);
+			IConstraintVerificationStatus currentStatus = constraint.getVerificationStatus();
+			// If the constraint verification resulted in an error, we display it immediately.
+			if(currentStatus instanceof ErrorVerificationStatus & canOpen(currentStatus)) {
+				openStatus(currentStatus);
+			}
+			return true;
+		}
+		if(status instanceof FailVerificationStatus || status instanceof ErrorVerificationStatus) {
+			List<IFix> fixes = IConstraintVerificationService.INSTANCE.fixes(status);
+			Shell shell = Display.getCurrent().getActiveShell();
+			int result = new FixDialog(shell, status, getMessage(status), fixes).open();
+			if(fixes.size() == 1 && result == 0) {
+				// get(0) because the size is equal to 1 by the previous test
+				fixes.get(0).runFix(status);
+			} else if(result > 1) {
+				fixes.get(result - 2).runFix(status);
+			}
+			return true;
+		}
+		return false;
+	}
+
+	/** {@inheritDoc} */
+	@Override
+	public boolean canOpen(IConstraintVerificationStatus status) {
+		return(status instanceof OutdatedVerificationStatus);
+	}
+
+	/** Dialog presenting the error/failure and the possible fix(es). */
+	private static class FixDialog extends MessageDialog {
+
+		/** List of possible fixes. */
+		List<IFix> fixes;
+
+		/** Constructor. */
+		public FixDialog(Shell parentShell, IConstraintVerificationStatus s, String msg,
+				List<IFix> fixes) {
+			super(parentShell, getTitle(s), null, msg, getIconType(s), getButtons(fixes), 1);
+			this.fixes = fixes;
+		}
+
+		/**
+		 * @param fixes
+		 * @return Buttons to display: "OK" is always displayed. In addition, if there is *only one
+		 *         fix*, we provide one button for this fix. If there is more than one possible fix,
+		 *         they will displayed instead horizontally (via getCustomArea).
+		 */
+		private static String[] getButtons(List<IFix> fixes) {
+			String[] res = new String[fixes.size() == 1 ? 2 : 1];
+			if(fixes.size() == 1) {
+				// get(0) because the size is equal to 1 by the previous test
+				res[0] = "Fix: " + fixes.get(0).getDescription();
+			}
+			res[res.length - 1] = "OK";
+			return res;
+		}
+
+		/**
+		 * @param s
+		 * @return the icon type corresponding to <code>s</code>.
+		 */
+		private static String getTitle(IConstraintVerificationStatus s) {
+			if(s instanceof FailVerificationStatus) {
+				return "Verification of constraint failed";
+			}
+			return "Error during constraint verification";
+		}
+
+		/**
+		 * @param s
+		 * @return the icon type corresponding to <code>s</code>.
+		 */
+		private static int getIconType(IConstraintVerificationStatus s) {
+			return s instanceof FailVerificationStatus ? MessageDialog.WARNING : ERROR;
+		}
+
+		/** {@inheritDoc} */
+		@Override
+		protected Control createCustomArea(Composite parent) {
+			if(fixes.size() <= 1) {
+				return null;
+			}
+			Group buttonGroup = new Group(parent, SWT.NONE);
+			buttonGroup.setLayout(new GridLayout());
+			buttonGroup.setLayoutData(new GridData(SWT.RIGHT, SWT.TOP, true, false));
+			buttonGroup.setText("Possible fixes");
+			for(IFix fix : fixes) {
+				Button button = new Button(buttonGroup, SWT.None);
+				button.setText(fix.getDescription());
+				button.addSelectionListener(new SelectionAdapter() {
+					@Override
+					public void widgetSelected(SelectionEvent event) {
+						buttonPressed(fixes.indexOf(fix) + 1);
+					}
+				});
+			}
+			// Does not matter what we return as long as it's not null
+			return buttonGroup;
+		}
+	}
+
+	/** {@inheritDoc} */
+	@Override
+	public String getMessage(IConstraintVerificationStatus status) {
+		// By default, no message. To be specialized by inheriting classes.
+		return null;
+	}
+}