/*
    * This file is a part of CAST project.
    * (c) Copyright 2007, AGH University of Science & Technology
    * https://caribou.iisg.agh.edu.pl/trac/cast
    *
    * Licensed under the Eclipse Public License, Version 1.0 (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.eclipse.org/legal/epl-v10.html
   */
  /*
   * File: EditorUtil.java
   * Created: 2009-08-05
   * Author: czerwin
   * $Id$
   */
  
  package pl.edu.agh.cast.editor;
  
  import org.eclipse.core.resources.IProject;
  import org.eclipse.core.runtime.IConfigurationElement;
  import org.eclipse.core.runtime.Platform;
  import org.eclipse.swt.widgets.Display;
  import org.eclipse.ui.IEditorDescriptor;
  import org.eclipse.ui.IEditorInput;
  import org.eclipse.ui.IEditorPart;
  import org.eclipse.ui.IPerspectiveDescriptor;
  import org.eclipse.ui.IWorkbenchPage;
  import org.eclipse.ui.PartInitException;
  import org.eclipse.ui.PlatformUI;
  
  import pl.edu.agh.cast.Activator;
  import pl.edu.agh.cast.CastApplication;
  import pl.edu.agh.cast.CoreServiceLocator;
  import pl.edu.agh.cast.data.model.DataSetDescriptor;
  import pl.edu.agh.cast.data.model.IDataSet;
  import pl.edu.agh.cast.data.model.IElement;
  import pl.edu.agh.cast.data.model.Type;
  import pl.edu.agh.cast.editor.input.ModelEditorInput;
  import pl.edu.agh.cast.ui.DefaultPerspective;
  import pl.edu.agh.cast.ui.util.MsgBoxHelper;
  import pl.edu.agh.cast.util.Messages;
  
  /**
   * Editor's utilities.
   * 
   * @author AGH CAST Team
   */
  public final class EditorUtil {
  
  	/**
  	 * Editor extensions ID.
  	 */
  	private static final String EXTENSION_POINT_ID = "pl.edu.agh.cast.editors"; //$NON-NLS-1$
  
  	/**
  	 * ID of the <em>name</em> attribute of <code>pl.edu.agh.cast.editor</code> extension point element.
  	 */
  	public static final String EDITOR_NAME_ATTR_ID = "name"; //$NON-NLS-1$
  
  	/**
  	 * ID of the <em>id</em> attribute of <code>pl.edu.agh.cast.editor</code> extension point element.
  	 */
  	public static final String EDITOR_ID_ATTR_ID = "id"; //$NON-NLS-1$
  
  	/**
  	 * ID of the <em>typeId</em> attribute of <code>pl.edu.agh.cast.editor</code> extension point element.
  	 */
  	public static final String EDITOR_TYPEID_ATTR_ID = "typeId"; //$NON-NLS-1$
  
  	/**
  	 * Returns all configuration elements from all extensions defined for <code>pl.edu.agh.cast.editor</code> extension
  	 * point.
  	 * 
  	 * @return array of configuration elements
  	 */
  	public static IConfigurationElement[] getEditorConfiguration() {
  		return Platform.getExtensionRegistry().getConfigurationElementsFor(EXTENSION_POINT_ID);
  	}
  
  	/**
  	 * Opens new editor for {@link pl.edu.agh.cast.data.model.DataSetDescriptor}.
  	 * 
  	 * @param descriptor
  	 *            data set descriptor
  	 * @return editor part
  	 */
  	public static IEditorPart openNewEditor(DataSetDescriptor descriptor) throws PartInitException {
  		// find editor ID compatible with type provided in descriptor
  		String editorId = findEditorId(descriptor.getType());
  		IEditorDescriptor editorDescriptor = PlatformUI.getWorkbench().getEditorRegistry().findEditor(editorId);
  		if (editorDescriptor == null) {
  			MsgBoxHelper.showInfoBox(Display.getCurrent().getActiveShell(), Messages.EditorUtil_2,
  			        Messages.EditorUtil_3);
  			return null;
  		}
  
  		// get model
  		IDataSet<? extends IElement> model = CoreServiceLocator.getPersistenceProvider().getDataSet(descriptor);
 		if (model == null) {
 			Activator.getLogger().error(
 					String.format("Inconsistent database. Data set for UUID %s was not found!", //$NON-NLS-1$
 			        descriptor.getId().toString()));
 			MsgBoxHelper.showErrorBox(Display.getCurrent().getActiveShell(), Messages.EditorUtil_0,
 			        Messages.EditorUtil_4);
 			return null;
 		}
 
 		// get diagram info
 //		ProjectUtil.NewDiagramInfo diagramInfo = ProjectUtil.getInstance().getNewDiagramInfo(getActiveProject());
 //		if (diagramInfo.cancelled) {
 //			return null;
 //		}
 
 		// create editor input, get workbench
 		IEditorInput editorInput = new ModelEditorInput<IDataSet<? extends IElement>>(model);
 		IWorkbenchPage workbenchPage = PlatformUI.getWorkbench().getActiveWorkbenchWindow().getActivePage();
 
 		switchToDiagramPerspective();
 
 //		ProjectStore modelStore = ProjectStore.getInstance();
 //		if (!modelStore.isInitialized(project)) {
 //			modelStore.init(project);
 //		}
 
 		// determine if new editor should be opened or restored
 		IEditorPart editorPart = workbenchPage.findEditor(editorInput);
 		if (editorPart == null) {
 			editorPart = workbenchPage.openEditor(editorInput, editorId);
 		} else {
 			workbenchPage.activate(editorPart);
 		}
 
 		return editorPart;
 	}
 
 	/**
 	 * Method is switching to default workbench perspective.
 	 */
 	public static void switchToDiagramPerspective() {
 		IPerspectiveDescriptor diagramPerspective = PlatformUI.getWorkbench().getPerspectiveRegistry()
 		        .findPerspectiveWithId(DefaultPerspective.ID);
 
 		PlatformUI.getWorkbench().getActiveWorkbenchWindow().getActivePage().setPerspective(diagramPerspective);
 	}
 
 	/**
 	 * Finds editor compatible with provided type.
 	 * 
 	 * @param type
 	 *            type which should be compatible with editor
 	 * @return editor ID
 	 */
 	private static String findEditorId(Type type) {
 		// find explicit editor ID and type ID mapping (without checking subtypes)
 		for (IConfigurationElement conf : getEditorConfiguration()) {
 			if (conf.getAttribute(EDITOR_TYPEID_ATTR_ID).equals(type.toString())) {
 				return conf.getAttribute(EDITOR_ID_ATTR_ID);
 			}
 		}
 
 		return null;
 	}
 
 	/**
 	 * Returns active project. If there is no active project message box will be shown.
 	 * 
 	 * @return active project
 	 */
 	@SuppressWarnings("unused")
     private static IProject getActiveProject() {
 		IProject project = CastApplication.getActiveProject();
 
 		if (project == null) {
 			MsgBoxHelper.showErrorBox(Display.getCurrent().getActiveShell(), Messages.AbstractOpenEditorAction_0,
 			        Messages.AbstractOpenEditorAction_1);
 		}
 
 		return project;
 	}
 
 }