/*
    * 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.eclipse.jface.dialogs.IMessageProvider;
  import org.eclipse.jface.dialogs.TitleAreaDialog;
  import org.eclipse.swt.SWT;
  import org.eclipse.swt.graphics.Point;
  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.Shell;
  import org.eclipse.swt.widgets.Text;
  
  /** Generic error dialog to be used in try/catch blocks */
  public class ErrorFeedback extends TitleAreaDialog {
  	private static final long serialVersionUID = -8918084784628179044L;
  
  	private final static Log log = LogFactory.getLog(ErrorFeedback.class);
  
  	private final String message;
  	private final Throwable exception;
  
  	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 ErrorFeedback(newShell(), message, e).open();
  	}
  
  	public static void show(String message) {
  		new ErrorFeedback(newShell(), message, null).open();
  	}
  
  	private static Shell newShell() {
  		return new Shell(getDisplay(), SWT.NO_TRIM);
  	}
  
  	/** 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 ErrorFeedback(Shell parentShell, String message, Throwable e) {
  		super(parentShell);
  		setShellStyle(SWT.NO_TRIM);
  		this.message = message;
  		this.exception = e;
  		log.error(message, e);
  	}
  
  	protected Point getInitialSize() {
  		if (exception != null)
  			return new Point(800, 600);
  		else
  			return new Point(400, 300);
  	}
  
  	@Override
  	protected Control createDialogArea(Composite parent) {
  		Composite dialogarea = (Composite) super.createDialogArea(parent);
  		dialogarea.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
  		Composite composite = new Composite(dialogarea, SWT.NONE);
  		composite.setLayout(new GridLayout(2, false));
  		composite.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
  
  		setMessage(message != null ? message + (exception != null ? ": " + exception.getMessage() : "")
  				: exception != null ? exception.getMessage() : "Unkown Error", IMessageProvider.ERROR);
  
 		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;
 	}
 
 	protected void configureShell(Shell shell) {
 		super.configureShell(shell);
 		shell.setText("Error");
 	}
 }