/*******************************************************************************
 * Copyright (c) 2004 - 2005 University Of British Columbia 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:
 *     University Of British Columbia - initial API and implementation
 *******************************************************************************/
/*
 * Created on Aug 6, 2004
  */
package org.eclipse.mylyn.java.ui.editor;

import org.eclipse.jdt.core.IImportContainer;
import org.eclipse.jdt.core.IImportDeclaration;
import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.ISourceRange;
import org.eclipse.jdt.core.ISourceReference;
import org.eclipse.jdt.core.JavaModelException;
import org.eclipse.jdt.internal.ui.javaeditor.ClassFileEditor;
import org.eclipse.jdt.internal.ui.javaeditor.IClassFileEditorInput;
import org.eclipse.jface.text.ITextViewerExtension5;
import org.eclipse.jface.text.source.ISourceViewer;
import org.eclipse.swt.custom.StyledText;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.ui.IPartService;
import org.eclipse.ui.IWorkbenchPart;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.views.contentoutline.ContentOutline;

import org.eclipse.mylyn.core.MylarPlugin;

/**
 * @author Mik Kersten
 */
public class MylarClassFileEditor extends ClassFileEditor {

//    private final ActiveFoldingListener FOLDING_LISTENER = new ActiveFoldingListener(this);
    
    @Override
    public void createPartControl(Composite parent) {
        super.createPartControl(parent);

        PlatformUI.getWorkbench().getDisplay().asyncExec(new Runnable() {
            public void run() {
                ContextCorePlugin.getTaskscapeManager().addListener(FOLDING_LISTENER);
            }
        });
    } 
    
    
	// EXPOSED METHODS FROM SUPER CLASS, DO NOT MODIFY
	// -----------------------------------------------
	
	/**
	 * Computes and returns the source reference that includes the caret and
	 * serves as provider for the outline page selection and the editor range
	 * indication.
	 * 
	 * @return the computed source reference
	 * @since 3.0
	 */
    @Override
	protected ISourceReference computeHighlightRangeSourceReference() {
		ISourceViewer sourceViewer= getSourceViewer();
		if (sourceViewer == null)
			return null;
			
		StyledText styledText= sourceViewer.getTextWidget();
		if (styledText == null)
			return null;
		
		int caret= 0;
		if (sourceViewer instanceof ITextViewerExtension5) {
			ITextViewerExtension5 extension= (ITextViewerExtension5)sourceViewer;
			caret= extension.widgetOffset2ModelOffset(styledText.getCaretOffset());
		} else {
			int offset= sourceViewer.getVisibleRegion().getOffset();
			caret= offset + styledText.getCaretOffset();
		}

		IJavaElement element= getElementAt(caret, false);
		
		if ( !(element instanceof ISourceReference))
			return null;
		
		if (element.getElementType() == IJavaElement.IMPORT_DECLARATION) {
			
			IImportDeclaration declaration= (IImportDeclaration) element;
			IImportContainer container= (IImportContainer) declaration.getParent();
			ISourceRange srcRange= null;
			
			try {
				srcRange= container.getSourceRange();
			} catch (JavaModelException e) {
				ContextCorePlugin.log(this.getClass().toString(), e);
			}
			
			if (srcRange != null && srcRange.getOffset() == caret)
				return container;
		}
		
		return (ISourceReference) element;
	}
	
	/**
	 * Synchronizes the outliner selection with the given element
	 * position in the editor.
	 * 
	 * @param element the java element to select
	 * @param checkIfOutlinePageActive <code>true</code> if check for active outline page needs to be done
	 */
    @Override
	protected void synchronizeOutlinePage(ISourceReference element, boolean checkIfOutlinePageActive) {
		if (fOutlinePage != null && element != null && !(checkIfOutlinePageActive && isJavaOutlinePageActive())) {
			fOutlineSelectionChangedListener.uninstall(fOutlinePage);
			fOutlinePage.select(element);
			fOutlineSelectionChangedListener.install(fOutlinePage);
		}
	}
	
	@Override
	protected IJavaElement getElementAt(int offset) {
		if (getEditorInput() instanceof IClassFileEditorInput) {
			try {
				IClassFileEditorInput input= (IClassFileEditorInput) getEditorInput();
				return input.getClassFile().getElementAt(offset);
			} catch (JavaModelException e) {
				ContextCorePlugin.log(this.getClass().toString(), e);
			}
		}
		return null;
	}
	
	private boolean isJavaOutlinePageActive() {
		IWorkbenchPart part= getActivePart();
		return part instanceof ContentOutline && ((ContentOutline)part).getCurrentPage() == fOutlinePage;
	}
	
	private IWorkbenchPart getActivePart() {
		IWorkbenchWindow window= getSite().getWorkbenchWindow();
		IPartService service= window.getPartService();
		IWorkbenchPart part= service.getActivePart();
		return part;
	}
}