/*
    * Copyright (C) 2007-2012 Argeo 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.argeo.cms.ui.workbench.internal.jcr.commands;
  
  import java.security.Principal;
  
  import javax.jcr.Node;
  import javax.jcr.RepositoryException;
  import javax.jcr.Session;
  import javax.jcr.security.AccessControlEntry;
  import javax.jcr.security.AccessControlList;
  import javax.jcr.security.AccessControlManager;
  import javax.jcr.security.Privilege;
  
  import org.argeo.cms.ui.jcr.JcrImages;
  import org.argeo.cms.ui.jcr.model.SingleJcrNodeElem;
  import org.argeo.cms.ui.jcr.model.WorkspaceElem;
  import org.argeo.cms.ui.workbench.WorkbenchUiPlugin;
  import org.argeo.eclipse.ui.EclipseUiException;
  import org.argeo.eclipse.ui.EclipseUiUtils;
  import org.argeo.eclipse.ui.TreeParent;
  import org.argeo.eclipse.ui.dialogs.ErrorFeedback;
  import org.argeo.jcr.JcrUtils;
  import org.eclipse.core.commands.AbstractHandler;
  import org.eclipse.core.commands.ExecutionEvent;
  import org.eclipse.core.commands.ExecutionException;
  import org.eclipse.jface.dialogs.Dialog;
  import org.eclipse.jface.dialogs.IMessageProvider;
  import org.eclipse.jface.dialogs.MessageDialog;
  import org.eclipse.jface.dialogs.TitleAreaDialog;
  import org.eclipse.jface.viewers.ISelection;
  import org.eclipse.jface.viewers.IStructuredSelection;
  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.Label;
  import org.eclipse.swt.widgets.Shell;
  import org.eclipse.ui.handlers.HandlerUtil;
  
  /** Open a dialog to remove privileges from the selected node */
  public class RemovePrivileges extends AbstractHandler {
  	public final static String ID = WorkbenchUiPlugin.PLUGIN_ID
  			+ ".removePrivileges";
  
  	public Object execute(ExecutionEvent event) throws ExecutionException {
  
  		ISelection selection = HandlerUtil.getActiveWorkbenchWindow(event)
  				.getActivePage().getSelection();
  		if (selection != null && !selection.isEmpty()
  				&& selection instanceof IStructuredSelection) {
  			Object obj = ((IStructuredSelection) selection).getFirstElement();
  			TreeParent uiNode = null;
  			Node jcrNode = null;
  
  			if (obj instanceof SingleJcrNodeElem) {
  				uiNode = (TreeParent) obj;
  				jcrNode = ((SingleJcrNodeElem) uiNode).getNode();
  			} else if (obj instanceof WorkspaceElem) {
  				uiNode = (TreeParent) obj;
  				jcrNode = ((WorkspaceElem) uiNode).getRootNode();
  			} else
  				return null;
  
  			try {
  				String targetPath = jcrNode.getPath();
  				Dialog dialog = new RemovePrivDialog(
  						HandlerUtil.getActiveShell(event),
  						jcrNode.getSession(), targetPath);
  				dialog.open();
  				return null;
  			} catch (RepositoryException re) {
  				throw new EclipseUiException("Unable to retrieve "
  						+ "path or JCR session to add privilege on " + jcrNode,
  						re);
  			}
  		} else {
  			ErrorFeedback.show("Cannot add privileges");
  		}
  		return null;
  	}
  
 	private class RemovePrivDialog extends TitleAreaDialog {
 		private static final long serialVersionUID = 280139710002698692L;
 
 		private Composite body;
 
 		private final String path;
 		private final Session session;
 
 		public RemovePrivDialog(Shell parentShell, Session session, String path) {
 			super(parentShell);
 			this.session = session;
 			this.path = path;
 		}
 
 		@Override
 		protected void configureShell(Shell newShell) {
 			super.configureShell(newShell);
 			newShell.setText("Remove privileges");
 		}
 
 		protected Control createDialogArea(Composite parent) {
 			Composite dialogarea = (Composite) super.createDialogArea(parent);
 			dialogarea.setLayoutData(new GridData(SWT.CENTER, SWT.TOP, true,
 					true));
 			body = new Composite(dialogarea, SWT.NONE);
 			body.setLayoutData(EclipseUiUtils.fillAll());
 			refreshContent();
 			parent.pack();
 			return body;
 		}
 
 		private void refreshContent() {
 			EclipseUiUtils.clear(body);
 			try {
 				AccessControlManager acm = session.getAccessControlManager();
 				AccessControlList acl = JcrUtils
 						.getAccessControlList(acm, path);
 				if (acl == null || acl.getAccessControlEntries().length <= 0)
 					setMessage("No privilege are defined on this node",
 							IMessageProvider.INFORMATION);
 				else {
 					body.setLayout(new GridLayout(3, false));
 					for (AccessControlEntry ace : acl.getAccessControlEntries()) {
 						addOnePrivRow(body, ace);
 					}
 					setMessage("Remove some of the defined privileges",
 							IMessageProvider.INFORMATION);
 				}
 			} catch (RepositoryException e) {
 				throw new EclipseUiException("Unable to list privileges on "
 						+ path, e);
 			}
 			body.layout(true, true);
 		}
 
 		private void addOnePrivRow(Composite parent, AccessControlEntry ace) {
 			Principal currentPrincipal = ace.getPrincipal();
 			final String currPrincipalName = currentPrincipal.getName();
 			new Label(parent, SWT.WRAP).setText(currPrincipalName);
 			new Label(parent, SWT.WRAP).setText(privAsString(ace
 					.getPrivileges()));
 			final Button rmBtn = new Button(parent, SWT.FLAT);
 			rmBtn.setImage(JcrImages.REMOVE);
 
 			rmBtn.addSelectionListener(new SelectionAdapter() {
 				private static final long serialVersionUID = 7566938841363890730L;
 
 				@Override
 				public void widgetSelected(SelectionEvent e) {
 
 					if (MessageDialog.openConfirm(rmBtn.getShell(),
 							"Confirm deletion",
 							"Are you sure you want to remove this privilege?")) {
 						try {
 							session.save();
 							JcrUtils.clearAccessControList(session, path,
 									currPrincipalName);
 							session.save();
 							refreshContent();
 						} catch (RepositoryException re) {
 							throw new EclipseUiException("Unable to "
 									+ "remove privilege for "
 									+ currPrincipalName + " on " + path, re);
 						}
 					}
 
 					super.widgetSelected(e);
 				}
 			});
 
 		}
 
 		private String privAsString(Privilege[] currentPrivileges) {
 
 			StringBuilder builder = new StringBuilder();
 			builder.append("[ ");
 			for (Privilege priv : currentPrivileges) {
 				builder.append(priv.getName()).append(", ");
 			}
 			if (builder.length() > 3)
 				return builder.substring(0, builder.length() - 2) + " ]";
 			else
 				return "[]";
 
 		}
 	}
 }