EDIT

/**

* Copyright (C) 2007 EDIT

* European Distributed Institute of Taxonomy

* http://www.e-taxonomy.eu

*

* The contents of this file are subject to the Mozilla Public License Version 1.1

* See LICENSE.TXT at the top of this package for the full license terms.

*/

package eu.etaxonomy.taxeditor.view.e4;

import javax.inject.Inject;

import org.apache.logging.log4j.LogManager;

import org.apache.logging.log4j.Logger;

import org.eclipse.e4.core.contexts.ContextInjectionFactory;

import org.eclipse.e4.core.contexts.IEclipseContext;

import org.eclipse.jface.viewers.Viewer;

import org.eclipse.swt.SWT;

import org.eclipse.swt.SWTException;

import org.eclipse.swt.widgets.Composite;

import org.eclipse.swt.widgets.Control;

import org.eclipse.swt.widgets.Display;

import org.eclipse.ui.forms.IFormPart;

import org.eclipse.ui.forms.ManagedForm;

import org.eclipse.ui.forms.widgets.ScrolledForm;

import eu.etaxonomy.taxeditor.model.IDirtyMarkable;

import eu.etaxonomy.taxeditor.model.MessagingUtils;

import eu.etaxonomy.taxeditor.preference.PreferencesUtil;

import eu.etaxonomy.taxeditor.remoting.CdmEagerLoadingException;

import eu.etaxonomy.taxeditor.ui.element.AbstractFormSection;

import eu.etaxonomy.taxeditor.ui.element.CdmFormFactory;

import eu.etaxonomy.taxeditor.ui.element.LayoutConstants;

import eu.etaxonomy.taxeditor.ui.element.RootElement;

import eu.etaxonomy.taxeditor.ui.section.occurrence.EmptySection;

import eu.etaxonomy.taxeditor.view.detail.CdmSectionPart;

/**

 * @author pplitzner

 * @date 18.07.2017

 */

public abstract class AbstractCdmDataViewer extends Viewer {

	private static final Logger logger = LogManager.getLogger();

	protected ManagedForm managedForm;

	protected CdmFormFactory formFactory;

	protected ScrolledForm scrolledForm;

	private Composite body;

	protected RootElement rootElement;

	@Inject

	protected IEclipseContext context;

	//TODO: create a super class for this?

	private Object input;

	protected IDirtyMarkable part;

	@Inject

	public AbstractCdmDataViewer() {

	}

	public void init(Composite parent, IDirtyMarkable part) {

	    this.part = part;

		managedForm = new ManagedForm(parent){

			@Override

			public void dirtyStateChanged() {

			    markViewPartDirty();

			}

		};

		createFormFactory();

		scrolledForm = managedForm.getForm();

		body = scrolledForm.getBody();

		body.setLayout(LayoutConstants.LAYOUT());

		rootElement = new RootElement(formFactory, body);

	}

    protected void createEmptySection(String message, RootElement parent) {

        destroySections();

        EmptySection emptySection = formFactory.createEmptySection(message, formFactory, parent, SWT.NONE);

        addPart(emptySection);

    }

    public void showEmptyPage(String message){

    	destroySections();

        createEmptySection(message, rootElement);

    }

    protected void markViewPartDirty(){

        part.changed(input);

    }

	protected void createFormFactory() {

		if(formFactory != null){

			formFactory.dispose();

			formFactory = null;

		}

		formFactory =  new CdmFormFactory(Display.getCurrent(), this);

		ContextInjectionFactory.inject(formFactory, context);

	}

	@Override

	public Control getControl() {

	    if(body!=null){

	        if(body.isDisposed()){

	            return null;

	        }

	        for(Control child : body.getChildren()){

	            return child;

	        }

	    }

		return body;

	}

	@Override

	public void setInput(Object input) {

		this.input = input;

		if(input!=null){

		    try{

		        refresh();

		    }catch(CdmEagerLoadingException e){

		        logger.error(e);

		    }

		}

	}

	@Override

	public Object getInput() {

		return input;

	}

	@Override

	public void refresh() {

		showParts();

		if(input!=null){

		    managedForm.setInput(input);

		}

		managedForm.refresh();

//		managedForm.reflow(true);

	}

	public void layout(){

		body.layout();

	}

	protected abstract void showParts();

	public void destroySections() {

		for (IFormPart formPart : managedForm.getParts()){

			removePart((CdmSectionPart<?>) formPart);

		}

		managedForm.setInput(null);

		try{

		    formFactory.destroyElement(rootElement);

		}catch (SWTException e){

		    if (PreferencesUtil.isShowUpWidgetIsDisposedMessages() && e.getMessage().equals("Widget is disposed")){

                MessagingUtils.errorDialog("Widget is disposed",

                        null,

                        MessagingUtils.WIDGET_IS_DISPOSED_MESSAGE,

                        null,

                        e,

                        true);

            }

		}

		createFormFactory();

		rootElement = new RootElement(formFactory, body);

		for(Control control : body.getChildren()){

			try{

				if (control != null && !control.isDisposed()){

					control.dispose();

				}

			}catch(SWTException e){

				if (PreferencesUtil.isShowUpWidgetIsDisposedMessages() && e.getMessage().equals("Widget is disposed")){

                    MessagingUtils.errorDialog("Widget is disposed",

                            null,

                            MessagingUtils.WIDGET_IS_DISPOSED_MESSAGE,

                            null,

                            e,

                            true);

                }

			}

			control = null;

		}

	}

	public void setFocus(){

		// we have to set focus to a control of this viewer

		// otherwise, after opening a dialog from the details, the focus will not be

		// given back to the details view but to the editor

		for(Control child : body.getChildren()){

			child.setFocus();

			break;

		}

	}

	public void reflow(){

		managedForm.reflow(true);

	}

	protected void removePart(CdmSectionPart<?> sectionPart){

		managedForm.removePart(sectionPart);

		formFactory.removePropertyChangeListener(sectionPart);

	}

	protected void addPart(AbstractFormSection<?> section){

		CdmSectionPart<?> sectionPart = new CdmSectionPart<>(section);

		managedForm.addPart(sectionPart);

		formFactory.addPropertyChangeListener(sectionPart);

	}

}