plugins/languages/common/org.eclipse.papyrus.designer.languages.common.codegen.ui/src/org/eclipse/papyrus/designer/languages/common/codegen/ui/ChooseGenerator.java

package org.eclipse.papyrus.designer.languages.common.codegen.ui;

import java.util.List;
import java.util.regex.Pattern;

import org.eclipse.emf.transaction.util.TransactionUtil;
import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.papyrus.designer.languages.common.base.ElementUtils;
import org.eclipse.papyrus.designer.languages.common.extensionpoints.GeneratorSelectionDialog;
import org.eclipse.papyrus.designer.languages.common.extensionpoints.ILangCodegen;
import org.eclipse.papyrus.designer.languages.common.extensionpoints.LanguageCodegen;
import org.eclipse.papyrus.designer.languages.common.extensionpoints.Messages;
import org.eclipse.papyrus.designer.languages.common.profile.CommonProfileResource;
import org.eclipse.papyrus.designer.languages.common.profile.Codegen.GeneratorHint;
import org.eclipse.papyrus.designer.languages.common.profile.Codegen.Language;
import org.eclipse.papyrus.designer.transformation.base.utils.ApplyProfile;
import org.eclipse.papyrus.designer.transformation.base.utils.CommandSupport;
import org.eclipse.papyrus.uml.tools.utils.PackageUtil;
import org.eclipse.papyrus.uml.tools.utils.StereotypeUtil;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.uml2.uml.NamedElement;
import org.eclipse.uml2.uml.Package;
import org.eclipse.uml2.uml.PackageableElement;
import org.eclipse.uml2.uml.util.UMLUtil;

public class ChooseGenerator {
	// name of package in which languages are stored
	public static final String LANGUAGES_PKG = "languages"; //$NON-NLS-1$

	/**
	 * Interactively choose a generator for a given set of languages (pattern).
	 * If only one generator is available, it returns this generator
	 * immediately.
	 * 
	 * @param languagePattern
	 * @param pe
	 *            a packageable element for which we want to choose a code generator
	 * @return a list of code generators
	 */
	public static ILangCodegen choose(Pattern languagePattern, PackageableElement pe) {
		List<ILangCodegen> eligibleGenerators = LanguageCodegen.getEligibleGeneratorList(languagePattern, pe);
		if (eligibleGenerators.size() == 0) {
			// retry with all generators (eligibility is currently based on the application of language-specific
			// profiles which might not be applied by users)
			eligibleGenerators = LanguageCodegen.getCodegenList(languagePattern);
		}
		
		if (eligibleGenerators.size() == 1) {
			return eligibleGenerators.get(0);
		}
		Shell shell = Display.getCurrent().getActiveShell();
		if (eligibleGenerators.size() > 1) {
			GeneratorSelectionDialog dialog = new GeneratorSelectionDialog(shell, eligibleGenerators);
			if (dialog.open() == IDialogConstants.OK_ID) {

				ILangCodegen codeGen = (ILangCodegen) dialog.getResult()[0];
				Boolean storeResult = (Boolean) dialog.getResult()[1];
				if (storeResult) {
					storeGeneratorID(pe, LanguageCodegen.getLanguage(codeGen), LanguageCodegen.getID(codeGen));
				}
				return codeGen;
			}
		}
		else {
			// echo language pattern in a more readible way: without escape characters that are used for
			// the "+" in C++
			String pattern = languagePattern.pattern().replace("\\", ""); //$NON-NLS-1$ //$NON-NLS-2$
			MessageDialog.openError(shell, Messages.LanguageCodegen_NoGeneratorsFound,
					String.format(Messages.LanguageCodegen_NoGeneratorsFoundLong, pattern));
		}

		return null;
	}

	public static void storeGeneratorID(PackageableElement pe, String languageName, final String generatorID) {
		final Package root = PackageUtil.getRootPackage(pe);
		CommandSupport.exec(TransactionUtil.getEditingDomain(pe), new ApplyProfile(root, CommonProfileResource.PROFILE_PATH_URI));
	
		NamedElement languageNE = ElementUtils.getQualifiedElementFromRS(pe, LANGUAGES_PKG + NamedElement.SEPARATOR + languageName);
		if (languageNE == null) {
			PackageUtil.loadPackage(CommonProfileResource.LANGUAGES_PATH_URI, pe.eResource().getResourceSet());
			languageNE = ElementUtils.getQualifiedElementFromRS(pe, LANGUAGES_PKG + NamedElement.SEPARATOR + languageName);
		}
		final Language language = (languageNE != null) ?
				UMLUtil.getStereotypeApplication(languageNE,  Language.class) :
				null;
		CommandSupport.exec(pe, Messages.ChooseGenerator_CHOOSE_GENERATOR, new Runnable() {
			
			@Override
			public void run() {
				GeneratorHint hint = StereotypeUtil.applyApp(root, GeneratorHint.class);
				hint.setLanguage(language);
				hint.setGeneratorID(generatorID);
			}
		});
	}


}