/*******************************************************************************
 * Copyright (c) 2007 VTT Technical Research Centre of Finland and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     VTT Technical Research Centre of Finland - initial API and implementation
 *******************************************************************************/
package org.simantics.proconf.g3d.views;

import org.eclipse.jface.viewers.ISelection;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.ui.IPartListener;
import org.eclipse.ui.IWorkbenchPart;
import org.eclipse.ui.forms.events.ExpansionAdapter;
import org.eclipse.ui.forms.events.ExpansionEvent;
import org.eclipse.ui.forms.widgets.FormToolkit;
import org.eclipse.ui.forms.widgets.ScrolledForm;
import org.eclipse.ui.forms.widgets.Section;
import org.simantics.db.Graph;
import org.simantics.db.GraphRequestAdapter;
import org.simantics.db.GraphRequestStatus;
import org.simantics.db.Session;
import org.simantics.proconf.g3d.common.StructuredResourceSelection;
import org.simantics.proconf.ui.workbench.ResourceEditorPart;
import org.simantics.utils.ui.ErrorLogger;
import org.simantics.utils.ui.ISelectionUtils;
import org.simantics.utils.ui.jface.BaseSelectionProvider;



public abstract class SinglePageResourceEditor extends ResourceEditorPart {
	private ScrolledForm form;
	private BaseSelectionProvider defaultInputSelectionProvider = new BaseSelectionProvider();
	protected FormToolkit toolkit;
	
	@Override
	public void createPartControl(Composite parent) {
		this.getEditorSite().getPage().addPartListener(new IPartListener() {
        	
        	boolean opened = false;
        	boolean activated = false;
        	
            public void partOpened(IWorkbenchPart part) {
                if (part.equals(SinglePageResourceEditor.this.getEditorSite().getPart())) {
                    opened = true;
                }
            }
            
            public void partActivated(IWorkbenchPart part) {
            	if (part.equals(SinglePageResourceEditor.this.getEditorSite().getPart())) {
                    if (opened & !activated) {
                    	activated = true;
                    	load();
                    }
            	}
            }
            
            public void partBroughtToTop(IWorkbenchPart part) {}
            
            public void partClosed(IWorkbenchPart part) {}
            
            public void partDeactivated(IWorkbenchPart part) {}
            
            private void load() {
            	Session ses = SinglePageResourceEditor.this.getSession();
                GraphRequestAdapter r = new GraphRequestAdapter() {
                	@Override
                	public GraphRequestStatus perform(Graph g)
                			throws Exception {
                		 reload(g);
                		return GraphRequestStatus.transactionComplete();
                	}
                };
                ses.asyncRead(r);
            }
        });
		try {
			toolkit = new FormToolkit(parent.getDisplay());
			form = getToolkit().createScrolledForm(parent);

			GridLayout layout = new GridLayout(2, false);
			form.getBody().setLayout(layout);
			form.getBody().setLayoutData(
					new GridData(GridData.FILL, GridData.FILL, true, true));

			// By default make this ViewPart use a default ISelectionProvider
			// that will offer the viewparts input resource as its selection.
			// The Resource is wrapped into a ResourceSelection object.
			// Any widgets created in createWidgets may override the default
			// selection provider.
			getEditorSite().setSelectionProvider(defaultInputSelectionProvider);

			beforeCreateWidgets();
			createWidgets();

			//reload();

			form.setText(getFormText());

			// Finally Set the default selection which will have an effect only
			// if nothing in createWidgets has overridden the default selection
			// provider.
			ISelection s = ISelectionUtils
					.createSelection(new StructuredResourceSelection(
							getInputResource()));
			defaultInputSelectionProvider.setSelection(s);

		} catch (Exception e) {
			Display d = getSite().getShell().getDisplay();
			d.asyncExec(new Runnable() {
				public void run() {
					getSite().getPage().closeEditor(
							SinglePageResourceEditor.this, false);
				}
			});

			ErrorLogger.defaultLogError("Single-page type editor failed to open, see exception for details",e);
		}
	}

	public ScrolledForm getActiveForm() {
		return form;
	}

	protected Composite getBody() {
		return form.getBody();
	}

	public Composite newGridSection(int formColumns, int childColumns,
			boolean equalWidth, boolean grabVertical, String text,
			String description) {
		return newGridSection(getBody(), formColumns, childColumns, equalWidth,
				grabVertical, text, description);
	}

	public Composite newGridSection(Composite parent, int formColumns,
			int childColumns, boolean equalWidth, boolean grabVertical,
			String text, String description) {
		FormToolkit toolkit = getToolkit();

		Section section = toolkit.createSection(parent, Section.DESCRIPTION
				| Section.TWISTIE | Section.TITLE_BAR | Section.EXPANDED);
		section.setLayoutData(new GridData(GridData.FILL, GridData.FILL, true,
				grabVertical, formColumns, 1));
		section.addExpansionListener(new ExpansionAdapter() {
			public void expansionStateChanged(ExpansionEvent e) {
				//System.out.println("SinglePageTypeEditor: expansionStateChanged " + e);
				//reflow(true);
			}
		});
		section.setText(text);
		section.setDescription(description);
		Composite sectionClient = toolkit.createComposite(section);
		sectionClient.setLayout(new GridLayout(childColumns, equalWidth));
		sectionClient.setLayoutData(new GridData());
		section.setClient(sectionClient);
		return sectionClient;
	}

	

	//----------------------------------------------------------------------
	// Getters

	public FormToolkit getToolkit() {
		return toolkit;
	}

	//----------------------------------------------------------------------
	// Event utilities

	public void reflow(boolean flushCache) {
		//System.out.println("FormTypeEditorBase.reflow(" + flushCache + ")");
		getActiveForm().reflow(flushCache);
	}

	@Override
	public void dispose() {
		if (toolkit != null) {
			toolkit.dispose();
		}
		super.dispose();
	}

	@Override
	public void setFocus() {
		//System.out.println("FormTypeEditorBase.setFocus(): Input = " + getInput());
		ScrolledForm form = getActiveForm();
		if (form != null) {
			form.setFocus();
		}
	}

	protected abstract String getFormText();

	/**
	 * Returns null by default which makes {@link #updateTitle()} not set the
	 * part name programmatically, i.e. the plugin-defined view name will stay.
	 * 
	 * @return
	 */
	protected String getTitleText() {
		return null;
	}

	/**
	 * Return null by default which makes {@link #updateTitle()} clear the
	 * tooltip.
	 * 
	 * @return
	 */
	protected String getTitleTooltip() {
		return null;
	}

	/**
	 * A method for performing initializations just before UI initialization.
	 */
	protected void beforeCreateWidgets() {
	}

	/**
	 * A method for initializing the UI of the view.
	 */
	protected void createWidgets() {
	}
}