/*******************************************************************************
 * Copyright (c) 2003, 2004 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.actions;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.resource.Resource;
import org.eclipse.jem.java.JavaClass;
import org.eclipse.jem.util.emf.workbench.ProjectUtilities;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jst.common.componentcore.util.ComponentUtilities;
import org.eclipse.jst.j2ee.ejb.EJBJar;
import org.eclipse.jst.j2ee.ejb.EnterpriseBean;
import org.eclipse.jst.j2ee.ejb.componentcore.util.EJBArtifactEdit;
import org.eclipse.jst.j2ee.internal.ejb.provider.J2EEJavaClassProviderHelper;
import org.eclipse.jst.j2ee.internal.plugin.J2EEEditorUtility;
import org.eclipse.jst.j2ee.internal.plugin.J2EEUIMessages;
import org.eclipse.jst.j2ee.web.componentcore.util.WebArtifactEdit;
import org.eclipse.jst.j2ee.webapplication.Servlet;
import org.eclipse.jst.j2ee.webapplication.WebApp;
import org.eclipse.jst.j2ee.webservice.wsdd.BeanLink;
import org.eclipse.jst.j2ee.webservice.wsdd.EJBLink;
import org.eclipse.jst.j2ee.webservice.wsdd.ServletLink;
import org.eclipse.ui.IEditorDescriptor;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.IEditorRegistry;
import org.eclipse.ui.IWorkbenchPage;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.part.FileEditorInput;
import org.eclipse.ui.part.ISetSelectionTarget;
import org.eclipse.wst.common.componentcore.resources.IVirtualComponent;
import org.eclipse.wst.common.internal.emfworkbench.WorkbenchResourceHelper;

/**
 * Action for opening a J2EE resource from the J2EE navigator.
 */
public class OpenJ2EEResourceAction extends AbstractOpenAction {
	
	public static final String ID = "org.eclipse.jst.j2ee.internal.internal.ui.actions.OpenJ2EEResourceAction"; //$NON-NLS-1$
	public static final String JAVA_EDITOR_ID = "org.eclipse.jst.j2ee.internal.internal.ejb.ui.java.EnterpriseBeanJavaEditor"; //$NON-NLS-1$
	public static final String BASE_JAVA_EDITOR_ID = "org.eclipse.jdt.ui.CompilationUnitEditor"; //$NON-NLS-1$
	
	protected static IEditorDescriptor javaEditorDescriptor;
	protected static IEditorDescriptor baseJavaEditorDescriptor;

	/**
	 * Create an instance of this class
	 */
	public OpenJ2EEResourceAction() {
		super(""); //$NON-NLS-1$
	}

	/**
	 * Returns the action ID.
	 */
	public String getID() {
		return ID;
	}

	public static IEditorDescriptor getJavaEditorDescriptor() {
		if (javaEditorDescriptor == null)
			javaEditorDescriptor = findEditorDescriptor(JAVA_EDITOR_ID);
		return javaEditorDescriptor;
	}

	public static IEditorDescriptor getBaseJavaEditorDescriptor() {
		if (baseJavaEditorDescriptor == null)
			baseJavaEditorDescriptor = findEditorDescriptor(BASE_JAVA_EDITOR_ID);
		return baseJavaEditorDescriptor;
	}
	
	/**
	 * open the appropriate editor
	 */
	protected void openAppropriateEditor(IResource r) {
		if (r == null)
			return;
		IWorkbenchPage page = null;
		IEditorPart editor = null;
		try {
			page = PlatformUI.getWorkbench().getActiveWorkbenchWindow().getActivePage();
			editor = page.openEditor(new FileEditorInput((IFile) r), currentDescriptor.getId());
			if (editor instanceof ISetSelectionTarget)
				((ISetSelectionTarget) editor).selectReveal(getStructuredSelection());
		} catch (Exception e) {
			MessageDialog.openError(page.getWorkbenchWindow().getShell(), J2EEUIMessages.getResourceString("Problems_Opening_Editor_ERROR_"), e.getMessage()); //$NON-NLS-1$ = "Problems Opening Editor"
		}
	}
	
	/**
	 * The user has invoked this action
	 */
	public void run() {
		if (!isEnabled())
			return;
		
		if (srcObject instanceof J2EEJavaClassProviderHelper) {
			((J2EEJavaClassProviderHelper) srcObject).openInEditor();
			return;
		}
		if (srcObject instanceof EObject) {
			EObject ro = (EObject) srcObject;
			IProject p = ProjectUtilities.getProject(ro);
			if (ro instanceof BeanLink) {
				openBeanLinkInJavaEditor((BeanLink) ro, p);
				return;
			}
			openAppropriateEditor(WorkbenchResourceHelper.getFile((EObject)srcObject));
		}
		else if (srcObject instanceof Resource)
			openAppropriateEditor(WorkbenchResourceHelper.getFile((Resource)srcObject));
	}

	/**
	 * The structured selection has changed in the workbench. Subclasses should override this method
	 * to react to the change. Returns true if the action should be enabled for this selection, and
	 * false otherwise.
	 * 
	 * When this method is overridden, the super method must always be invoked. If the super method
	 * returns false, this method must also return false.
	 * 
	 * @param sel the new structured selection
	 */
	public boolean updateSelection(IStructuredSelection s) {
		if (!super.updateSelection(s))
			return false;

		// Make sure this is one of the selections we can handle,
		// then set the source object as is. The run() will do the hard stuff.
		Object obj = s.getFirstElement();
		
		if (obj instanceof J2EEJavaClassProviderHelper)
			currentDescriptor = getJavaEditorDescriptor();
		else if (obj instanceof BeanLink)
			currentDescriptor = getBaseJavaEditorDescriptor();	
		else if (obj instanceof EObject) {
			IEditorRegistry registry = PlatformUI.getWorkbench().getEditorRegistry();
			currentDescriptor = registry.getDefaultEditor(WorkbenchResourceHelper.getFile((EObject)obj).getName());
		}
		else if (obj instanceof Resource) {
			IEditorRegistry registry = PlatformUI.getWorkbench().getEditorRegistry();
			currentDescriptor = registry.getDefaultEditor(WorkbenchResourceHelper.getFile((Resource)obj).getName());
		}
		else {
			currentDescriptor = null;
			return false;
		}
		setAttributesFromDescriptor();
		srcObject = obj;
		return true;
	}
	
	/**
	 * @param link
	 */
	private void openBeanLinkInJavaEditor(BeanLink link, IProject p) {
		String linkName = null;
		JavaClass javaClass = null;
		IVirtualComponent comp = ComponentUtilities.findComponent(link);
		// Handle EJB Link case
		if (link instanceof EJBLink) {
			linkName = ((EJBLink) link).getEjbLink();
			EJBArtifactEdit artifactEdit = null;
			try {
				artifactEdit = EJBArtifactEdit.getEJBArtifactEditForRead(comp);
				EJBJar ejbJar = artifactEdit.getEJBJar();
				if (ejbJar == null)
					return;
				EnterpriseBean bean = ejbJar.getEnterpriseBeanNamed(linkName);
				if (bean == null)
					return;
				javaClass = bean.getEjbClass();
			} finally {
				if (artifactEdit!=null)
					artifactEdit.dispose();
			}
		}
		// Handle Servlet Link case
		else {
			linkName = ((ServletLink) link).getServletLink();
			WebArtifactEdit artifactEdit = null;
			try {
				artifactEdit = WebArtifactEdit.getWebArtifactEditForRead(comp);
				WebApp webApp = artifactEdit.getWebApp();
			if (webApp == null)
				return;
			Servlet servlet = webApp.getServletNamed(linkName);
			if (servlet == null)
				return;
			javaClass = servlet.getServletClass();
			} finally {
				if (artifactEdit!=null)
					artifactEdit.dispose();
			}
		}
		// Open java editor on the selected objects associated java file
		try {
			J2EEEditorUtility.openInEditor(javaClass, p);
		} catch (Exception cantOpen) {
			cantOpen.printStackTrace();
		}
	}

	protected EObject getRootObject(Object obj) {
		if (obj instanceof EObject) {
			EObject refObj = (EObject) obj;
			while (refObj != null && refObj.eContainer() != null)
				refObj = refObj.eContainer();
			return refObj;
		}
		return null;
	}
}