/*
    * 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.eclipse.ui.dialogs;
  
  import java.io.PrintWriter;
  import java.io.StringWriter;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.argeo.eclipse.ui.EclipseUiException;
  import org.eclipse.swt.SWT;
  import org.eclipse.swt.events.ShellAdapter;
  import org.eclipse.swt.events.ShellEvent;
  import org.eclipse.swt.graphics.Point;
  import org.eclipse.swt.graphics.Rectangle;
  import org.eclipse.swt.layout.GridData;
  import org.eclipse.swt.layout.GridLayout;
  import org.eclipse.swt.widgets.Composite;
  import org.eclipse.swt.widgets.Control;
  import org.eclipse.swt.widgets.Display;
  import org.eclipse.swt.widgets.Label;
  import org.eclipse.swt.widgets.Shell;
  import org.eclipse.swt.widgets.Text;
  
  /** Generic error dialog to be used in try/catch blocks */
  class NonModalErrorFeedback {
  	private final static Log log = LogFactory
  			.getLog(NonModalErrorFeedback.class);
  
  	private final String message;
  	private final Throwable exception;
  
  	private Shell shell;
  
  	public static void show(String message, Throwable e) {
  		// rethrow ThreaDeath in order to make sure that RAP will properly clean
  		// up the UI thread
  		if (e instanceof ThreadDeath)
  			throw (ThreadDeath) e;
  
  		new NonModalErrorFeedback(getDisplay().getActiveShell(), message, e)
  				.open();
  	}
  
  	public static void show(String message) {
  		new NonModalErrorFeedback(getDisplay().getActiveShell(), message, null)
  				.open();
  	}
  
  	/** Tries to find a display */
  	private static Display getDisplay() {
  		try {
  			Display display = Display.getCurrent();
  			if (display != null)
  				return display;
  			else
  				return Display.getDefault();
  		} catch (Exception e) {
  			return Display.getCurrent();
  		}
  	}
  
  	public NonModalErrorFeedback(Shell parentShell, String message, Throwable e) {
  		this.message = message;
  		this.exception = e;
  		log.error(message, e);
  	}
  
  	public void open() {
  		if (shell != null)
  			throw new EclipseUiException("There is already a shell");
  		shell = new Shell(getDisplay(), SWT.NO_TRIM | SWT.BORDER | SWT.ON_TOP);
  		shell.setLayout(new GridLayout());
  		// shell.setText("Error");
  		shell.setSize(getInitialSize());
  		createDialogArea(shell);
  		// shell.pack();
  		// shell.layout();
  
  		Rectangle shellBounds = Display.getCurrent().getBounds();// RAP
  		Point dialogSize = shell.getSize();
  		int x = shellBounds.x + (shellBounds.width - dialogSize.x) / 2;
  		int y = shellBounds.y + (shellBounds.height - dialogSize.y) / 2;
  		shell.setLocation(x, y);
  
  		shell.addShellListener(new ShellAdapter() {
 			private static final long serialVersionUID = -2701270481953688763L;
 
 			@Override
 			public void shellDeactivated(ShellEvent e) {
 				closeShell();
 			}
 		});
 
 		shell.open();
 	}
 
 	protected void closeShell() {
 		shell.close();
 		shell.dispose();
 		shell = null;
 	}
 
 	protected Point getInitialSize() {
 		// if (exception != null)
 		// return new Point(800, 600);
 		// else
 		return new Point(400, 300);
 	}
 
 	protected Control createDialogArea(Composite parent) {
 		Composite dialogarea = new Composite(parent, SWT.NONE);
 		dialogarea.setLayout(new GridLayout());
 		// Composite dialogarea = (Composite) super.createDialogArea(parent);
 		dialogarea.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
 
 		Label messageLbl = new Label(dialogarea, SWT.NONE);
 		if (message != null)
 			messageLbl.setText(message);
 		else if (exception != null)
 			messageLbl.setText(exception.getLocalizedMessage());
 
 		Composite composite = new Composite(dialogarea, SWT.NONE);
 		composite.setLayout(new GridLayout(2, false));
 		composite.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
 
 		if (exception != null) {
 			Text stack = new Text(composite, SWT.MULTI | SWT.LEAD | SWT.BORDER
 					| SWT.V_SCROLL | SWT.H_SCROLL);
 			stack.setEditable(false);
 			stack.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
 			StringWriter sw = new StringWriter();
 			exception.printStackTrace(new PrintWriter(sw));
 			stack.setText(sw.toString());
 		}
 
 		// parent.pack();
 		return composite;
 	}
 }