/*******************************************************************************
 * Copyright (c) 2003, 2005 IBM Corporation 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:
 * IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jst.j2ee.internal.web.operations;

import java.lang.reflect.InvocationTargetException;
import java.net.URL;
import java.util.Iterator;
import java.util.Set;

import org.eclipse.core.commands.ExecutionException;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IFolder;
import org.eclipse.core.resources.IMarker;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.IWorkspaceRoot;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.core.runtime.Path;
import org.eclipse.emf.codegen.jet.JETEmitter;
import org.eclipse.emf.codegen.jet.JETException;
import org.eclipse.jdt.core.ICompilationUnit;
import org.eclipse.jdt.core.IJavaModelMarker;
import org.eclipse.jdt.core.IPackageFragment;
import org.eclipse.jdt.core.IPackageFragmentRoot;
import org.eclipse.jdt.core.JavaModelException;
import org.eclipse.jem.util.emf.workbench.ProjectUtilities;
import org.eclipse.jem.util.logger.proxy.Logger;
import org.eclipse.jst.common.internal.annotations.controller.AnnotationsController;
import org.eclipse.jst.common.internal.annotations.controller.AnnotationsControllerManager;
import org.eclipse.jst.common.internal.annotations.controller.AnnotationsControllerManager.Descriptor;
import org.eclipse.jst.j2ee.application.internal.operations.IAnnotationsDataModel;
import org.eclipse.jst.j2ee.internal.common.operations.INewJavaClassDataModelProperties;
import org.eclipse.jst.j2ee.internal.project.WTPJETEmitter;
import org.eclipse.jst.j2ee.internal.web.plugin.WebPlugin;
import org.eclipse.wst.common.componentcore.datamodel.FacetInstallDataModelProvider;
import org.eclipse.wst.common.componentcore.datamodel.FacetProjectCreationDataModelProvider;
import org.eclipse.wst.common.componentcore.datamodel.properties.IFacetDataModelProperties;
import org.eclipse.wst.common.componentcore.datamodel.properties.IFacetProjectCreationDataModelProperties;
import org.eclipse.wst.common.componentcore.datamodel.properties.IFacetProjectCreationDataModelProperties.FacetDataModelMap;
import org.eclipse.wst.common.componentcore.internal.operation.ArtifactEditProviderOperation;
import org.eclipse.wst.common.frameworks.datamodel.DataModelFactory;
import org.eclipse.wst.common.frameworks.datamodel.IDataModel;
import org.eclipse.wst.common.frameworks.internal.enablement.nonui.WFTWrappedException;
import org.eclipse.wst.common.frameworks.internal.plugin.WTPCommonPlugin;
import org.eclipse.wst.common.project.facet.core.IFacetedProject;
import org.eclipse.wst.common.project.facet.core.IProjectFacetVersion;
import org.eclipse.wst.common.project.facet.core.ProjectFacetsManager;

/**
 * The NewServletClassOperation is an IDataModelOperation following the
 * IDataModel wizard and operation framework.
 * 
 * @see org.eclipse.wst.common.frameworks.datamodel.IDataModelOperation
 * @see org.eclipse.wst.common.frameworks.datamodel.IDataModelProvider
 * 
 * It extends ArtifactEditProviderOperation to provide servlet specific java
 * class generation.
 * @see org.eclipse.wst.common.componentcore.internal.operation.ArtifactEditProviderOperation
 * 
 * This operation is used by the AddServletOperation to generate either an
 * annotated or non annotated java class for an added servlet. It shares the
 * NewServletClassDataModelProvider with the AddServletOperation to store the
 * appropriate properties required to generate the new servlet.
 * @see org.eclipse.jst.j2ee.internal.web.operations.AddServletOperation
 * @see org.eclipse.jst.j2ee.internal.web.operations.NewServletClassDataModelProvider
 * 
 * In the annotated case, a WTPJetEmitter servlet template is created and used
 * to generate the servlet java class with the embedded annotated tags.
 * @see org.eclipse.jst.j2ee.internal.project.WTPJETEmitter
 * @see org.eclipse.jst.j2ee.internal.web.operations.CreateServletTemplateModel
 * 
 * In the non annotated case, the same emitter is used to create the class with
 * the non annotated servlet template so the annotated tags are omitted.
 * 
 * Subclasses may extend this operation to provide their own specific servlet
 * java class generation. The execute method may be extended to do so. Also,
 * generateUsingTemplates is exposed.
 * 
 * The use of this class is EXPERIMENTAL and is subject to substantial changes.
 */
public class NewServletClassOperation extends ArtifactEditProviderOperation {

	/**
	 * XDoclet facet constants
	 */
	private static final String JST_WEB_XDOCLET_VERSION = "1.2.3"; //$NON-NLS-1$
	private static final String JST_WEB_XDOCLET = "jst.web.xdoclet"; //$NON-NLS-1$

	/**
	 * The extension name for a java class
	 */
	private static final String DOT_JAVA = ".java"; //$NON-NLS-1$

	/**
	 * platform plugin beginning for URI string
	 */
	// private static final String PLATFORM_PLUGIN = "platform:/plugin/";
	// //$NON-NLS-1$
	/**
	 * variable for the web plugin
	 */
	protected static final String WEB_PLUGIN = "WEB_PLUGIN"; //$NON-NLS-1$

	/**
	 * folder location of the servlet creation templates diretory
	 */
	protected static final String TEMPLATE_DIR = "/templates/"; //$NON-NLS-1$

	/**
	 * name of the template emitter to be used to generate the deployment
	 * descriptor from the tags
	 */
	protected static final String TEMPLATE_EMITTER = "org.eclipse.jst.j2ee.ejb.annotations.emitter.template"; //$NON-NLS-1$

	/**
	 * id of the builder used to kick off generation of web metadata based on
	 * parsing of annotations
	 */
	protected static final String BUILDER_ID = "builderId"; //$NON-NLS-1$

	/**
	 * This is the constructor which should be used when creating a
	 * NewServletClassOperation. An instance of the NewServletClassDataModel
	 * should be passed in. This does not accept null parameter. It will not
	 * return null.
	 * 
	 * @see ArtifactEditProviderOperation#ArtifactEditProviderOperation(IDataModel)
	 * @see NewServletClassDataModel
	 * 
	 * @param dataModel
	 * @return NewServletClassOperation
	 */
	public NewServletClassOperation(IDataModel dataModel) {
		super(dataModel);
	}

	/**
	 * Subclasses may extend this method to add their own actions during
	 * execution. The implementation of the execute method drives the running of
	 * the operation. This implemenatation will create the java source folder,
	 * create the java package, and then if using annotations, will use
	 * templates to generate an annotated servlet java class, or if it is not
	 * annotated, the servlet java class file will be created without the
	 * annotated tags using templates. Optionally, subclasses may extend the
	 * generateUsingTemplates or createJavaFile method rather than extend the
	 * execute method. This method will accept a null paramter.
	 * 
	 * @see org.eclipse.wst.common.frameworks.internal.operation.WTPOperation#execute(org.eclipse.core.runtime.IProgressMonitor)
	 * @see NewServletClassOperation#generateUsingTemplates(IProgressMonitor,
	 *      IPackageFragment)
	 * 
	 * @param monitor
	 * @throws CoreException
	 * @throws InterruptedException
	 * @throws InvocationTargetException
	 */
	public IStatus doExecute(IProgressMonitor monitor, IAdaptable info) throws ExecutionException {
		// Create source folder if it does not exist
		createJavaSourceFolder();
		// Create java package if it does not exist
		IPackageFragment pack = createJavaPackage();
		// Generate using templates
		try {
			generateUsingTemplates(monitor, pack);
		} catch (Exception e) {
			return WTPCommonPlugin.createErrorStatus(e.toString());
		}
		return OK_STATUS;
	}

	/**
	 * This method will return the java package as specified by the new java
	 * class data model. If the package does not exist, it will create the
	 * package. This method should not return null.
	 * 
	 * @see INewJavaClassDataModelProperties#JAVA_PACKAGE
	 * @see IPackageFragmentRoot#createPackageFragment(java.lang.String,
	 *      boolean, org.eclipse.core.runtime.IProgressMonitor)
	 * 
	 * @return IPackageFragment the java package
	 */
	protected final IPackageFragment createJavaPackage() {
		// Retrieve the package name from the java class data model
		String packageName = model.getStringProperty(INewJavaClassDataModelProperties.JAVA_PACKAGE);
		IPackageFragmentRoot packRoot = (IPackageFragmentRoot) model
				.getProperty(INewJavaClassDataModelProperties.JAVA_PACKAGE_FRAGMENT_ROOT);
		IPackageFragment pack = packRoot.getPackageFragment(packageName);
		// Handle default package
		if (pack == null) {
			pack = packRoot.getPackageFragment(""); //$NON-NLS-1$
		}
		// Create the package fragment if it does not exist
		if (!pack.exists()) {
			String packName = pack.getElementName();
			try {
				pack = packRoot.createPackageFragment(packName, true, null);
			} catch (JavaModelException e) {
				Logger.getLogger().log(e);
			}
		}
		// Return the package
		return pack;
	}

	/**
	 * Subclasses may extend this method to provide their own template based
	 * creation of an annotated servlet java class file. This implementation
	 * uses the creation of a CreateServletTemplateModel and the WTPJetEmitter
	 * to create the java class with the annotated tags. This method accepts
	 * null for monitor, it does not accept null for fragment. If annotations
	 * are not being used the tags will be omitted from the class.
	 * 
	 * @see CreateServletTemplateModel
	 * @see NewServletClassOperation#generateTemplateSource(CreateServletTemplateModel,
	 *      IProgressMonitor)
	 * 
	 * @param monitor
	 * @param fragment
	 * @throws CoreException
	 * @throws WFTWrappedException
	 */
	protected void generateUsingTemplates(IProgressMonitor monitor, IPackageFragment fragment) throws WFTWrappedException, CoreException {
		// Create the servlet template model
		CreateServletTemplateModel tempModel = createTemplateModel();
		IProject project = getTargetProject();
		String source;
		// Using the WTPJetEmitter, generate the java source based on the servlet template model
		try {
			source = generateTemplateSource(tempModel, monitor);
		} catch (Exception e) {
			throw new WFTWrappedException(e);
		}
		if (fragment != null) {
			// Create the java file
			String javaFileName = tempModel.getServletClassName() + DOT_JAVA;
			ICompilationUnit cu = fragment.getCompilationUnit(javaFileName);
			// Add the compilation unit to the java file
			if (cu == null || !cu.exists())
				cu = fragment.createCompilationUnit(javaFileName, source, true, monitor);
			IFile aFile = (IFile) cu.getResource();
			// Let the annotations controller process the annotated resource
			AnnotationsController controller = AnnotationsControllerManager.INSTANCE.getAnnotationsController(project);
			if (controller != null)
				controller.process(aFile);
		}
		
		// Add the xdoclet facet, if necessary, for xdoclet servlet creation
		try {
			installXDocletFacetIfNecessary(monitor, project);
		} catch (Exception e) {
			throw new WFTWrappedException(e);
		}
	}

	/**
	 * This method is intended for internal use only. This will add an webdoclet facet to the project.
	 * 
	 * @throws CoreException 
	 * @throws ExecutionException 
	 */
	private void installXDocletFacet(IProgressMonitor monitor, IProject project) throws CoreException, ExecutionException {
		IFacetedProject facetedProject = ProjectFacetsManager.create(project);
		Set fixedFacets = facetedProject.getFixedProjectFacets();
		IDataModel dm = DataModelFactory.createDataModel(new FacetInstallDataModelProvider());
		dm.setProperty(IFacetDataModelProperties.FACET_ID, JST_WEB_XDOCLET);
		dm.setProperty(IFacetDataModelProperties.FACET_PROJECT_NAME, project.getName());
		dm.setProperty(IFacetDataModelProperties.FACET_VERSION_STR, JST_WEB_XDOCLET_VERSION);
		IDataModel fdm = DataModelFactory.createDataModel(new FacetProjectCreationDataModelProvider());
		fdm.setProperty(IFacetProjectCreationDataModelProperties.FACET_PROJECT_NAME, project.getName());

		FacetDataModelMap map = (FacetDataModelMap) fdm.getProperty(IFacetProjectCreationDataModelProperties.FACET_DM_MAP);
		map.add(dm);

		fdm.getDefaultOperation().execute(monitor, null);
		facetedProject.setFixedProjectFacets(fixedFacets);
	}
	
	/**
	 * This method is intended for internal use only. This will check to see if it needs to add an 
	 * webdoclet facet to the project.
	 * 
	 * @throws CoreException 
	 * @throws ExecutionException 
	 */
	private void installXDocletFacetIfNecessary(IProgressMonitor monitor, IProject project) throws CoreException, ExecutionException {

		// If not using annotations, ignore the xdoclet facet
		if (!model.getBooleanProperty(IAnnotationsDataModel.USE_ANNOTATIONS))
			return;
		
		// If an extended annotations processor is added, ignore the default xdoclet one
		Descriptor descriptor = AnnotationsControllerManager.INSTANCE.getDescriptor(getTargetComponent().getProject());
		if (descriptor != null)
			return;

		// Otherwise check and see if the xdoclet facet is on the project yet
		IFacetedProject facetedProject = ProjectFacetsManager.create(project);
		Set facets = facetedProject.getProjectFacets();
		for (Iterator iter = facets.iterator(); iter.hasNext();) {
			IProjectFacetVersion facetVersion = (IProjectFacetVersion) iter.next();
			String facetID = facetVersion.getProjectFacet().getId();
			if (JST_WEB_XDOCLET.equals(facetID)) 
				return;
		}
		// Install xdoclet facet
		installXDocletFacet(monitor, project);
	}

	/**
	 * This method is intended for internal use only. This will use the
	 * WTPJETEmitter to create an annotated java file based on the passed in
	 * servlet class template model. This method does not accept null
	 * parameters. It will not return null. If annotations are not used, it will
	 * use the non annotated template to omit the annotated tags.
	 * 
	 * @see NewServletClassOperation#generateUsingTemplates(IProgressMonitor,
	 *      IPackageFragment)
	 * @see JETEmitter#generate(org.eclipse.core.runtime.IProgressMonitor,
	 *      java.lang.Object[])
	 * @see CreateServletTemplateModel
	 * 
	 * @param tempModel
	 * @param monitor
	 * @return String the source for the java file
	 * @throws JETException
	 */
	private String generateTemplateSource(CreateServletTemplateModel tempModel, IProgressMonitor monitor) throws JETException {
		URL templateURL = null;
		// If annotated, use annotated template
		if (model.getBooleanProperty(IAnnotationsDataModel.USE_ANNOTATIONS))
			templateURL = WebPlugin.getDefault().find(
					new Path(TEMPLATE_DIR + getDataModel().getStringProperty(INewServletClassDataModelProperties.TEMPLATE_FILE)));
		// Otherwise use non annotated template
		else
			templateURL = WebPlugin.getDefault().find(
					new Path(TEMPLATE_DIR
							+ getDataModel().getStringProperty(INewServletClassDataModelProperties.NON_ANNOTATED_TEMPLATE_FILE)));
		cleanUpOldEmitterProject();
		WTPJETEmitter emitter = new WTPJETEmitter(templateURL.toString(), this.getClass().getClassLoader());
		emitter.setIntelligentLinkingEnabled(true);
		emitter.addVariable(WEB_PLUGIN, WebPlugin.PLUGIN_ID);
		return emitter.generate(monitor, new Object[] { tempModel });
	}

	private void cleanUpOldEmitterProject() {
		IProject project = ProjectUtilities.getProject(WTPJETEmitter.PROJECT_NAME);
		if (project == null || !project.exists())
			return;
		try {
			IMarker[] markers = project.findMarkers(IJavaModelMarker.BUILDPATH_PROBLEM_MARKER, false, IResource.DEPTH_ZERO);
			for (int i = 0, l = markers.length; i < l; i++) {
				if (((Integer) markers[i].getAttribute(IMarker.SEVERITY)).intValue() == IMarker.SEVERITY_ERROR) {
					project.delete(true, new NullProgressMonitor());
					break;
				}
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	/**
	 * This method is intended for internal use only. This method will create an
	 * instance of the CreateServletTemplate model to be used in conjunction
	 * with the WTPJETEmitter. This method will not return null.
	 * 
	 * @see CreateServletTemplateModel
	 * @see NewServletClassOperation#generateUsingTemplates(IProgressMonitor,
	 *      IPackageFragment)
	 * 
	 * @return CreateServletTemplateModel
	 */
	private CreateServletTemplateModel createTemplateModel() {
		// Create the CreateServletTemplateModel instance with the new servlet
		// class data model
		CreateServletTemplateModel templateModel = new CreateServletTemplateModel(model);
		return templateModel;
	}

	/**
	 * This method will return the java source folder as specified in the java
	 * class data model. It will create the java source folder if it does not
	 * exist. This method may return null.
	 * 
	 * @see INewJavaClassDataModelProperties#SOURCE_FOLDER
	 * @see IFolder#create(boolean, boolean,
	 *      org.eclipse.core.runtime.IProgressMonitor)
	 * 
	 * @return IFolder the java source folder
	 */
	protected final IFolder createJavaSourceFolder() {
		// Get the source folder name from the data model
		String folderFullPath = model.getStringProperty(INewJavaClassDataModelProperties.SOURCE_FOLDER);
		IWorkspaceRoot root = ResourcesPlugin.getWorkspace().getRoot();
		IFolder folder = root.getFolder(new Path(folderFullPath));
		// If folder does not exist, create the folder with the specified path
		if (!folder.exists()) {
			try {
				folder.create(true, true, null);
			} catch (CoreException e) {
				Logger.getLogger().log(e);
			}
		}
		// Return the source folder
		return folder;
	}
}