/*******************************************************************************
 * Copyright (c) 2001, 2010 IBM Corporation 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:
 *     IBM Corporation - initial API and implementation
 *     Jens Lukowski/Innoopract - initial renaming/restructuring
 *     
 *******************************************************************************/
package org.eclipse.wst.xml.ui.internal.correction;

import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.ITextViewerExtension;
import org.eclipse.jface.text.Position;
import org.eclipse.jface.text.link.LinkedModeModel;
import org.eclipse.jface.text.link.LinkedModeUI;
import org.eclipse.jface.text.link.LinkedPosition;
import org.eclipse.jface.text.link.LinkedPositionGroup;
import org.eclipse.swt.graphics.Image;
import org.eclipse.text.edits.InsertEdit;
import org.eclipse.text.edits.MalformedTreeException;
import org.eclipse.text.edits.MultiTextEdit;
import org.eclipse.ui.texteditor.link.EditorLinkedModeUI;
import org.eclipse.wst.sse.core.internal.format.IStructuredFormatProcessor;
import org.eclipse.wst.sse.ui.internal.contentassist.ContentAssistUtils;
import org.eclipse.wst.xml.core.internal.provisional.document.IDOMNode;
import org.eclipse.wst.xml.core.internal.provisional.format.FormatProcessorXML;
import org.eclipse.wst.xml.ui.internal.Logger;
import org.eclipse.wst.xml.ui.internal.XMLUIMessages;
import org.eclipse.wst.xml.ui.internal.editor.XMLEditorPluginImageHelper;
import org.eclipse.wst.xml.ui.internal.editor.XMLEditorPluginImages;
import org.w3c.dom.Node;

public class SurroundWithNewElementQuickAssistProposal extends RenameInFileQuickAssistProposal {
	private static final String ELEMENT_NAME = "element"; //$NON-NLS-1$
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#apply(org.eclipse.jface.text.ITextViewer,
	 *      char, int, int)
	 */
	public void apply(ITextViewer viewer, char trigger, int stateMask, int offset) {
		try {
			int startTagOffset = offset;
			int endTagOffset = offset + viewer.getSelectedRange().y;

			// surround the node if no selection
			if (startTagOffset == endTagOffset) {
				IDOMNode cursorNode = (IDOMNode) ContentAssistUtils.getNodeAt(viewer, offset);
				// use parent node if text node is empty
				if ((cursorNode.getNodeType() == Node.TEXT_NODE) && (cursorNode.getNodeValue().trim().length() == 0)) {
					cursorNode = (IDOMNode) cursorNode.getParentNode();
				}

				startTagOffset = cursorNode.getStartOffset();
				endTagOffset = cursorNode.getEndOffset();
			}

			// insert new element
			MultiTextEdit multiTextEdit = new MultiTextEdit();
			// element tag name cannot be DBCS, do not translate "<element>"
			// and "</element>"
			final String startElement = "<" + ELEMENT_NAME + ">"; //$NON-NLS-1$ //$NON-NLS-2$
			multiTextEdit.addChild(new InsertEdit(startTagOffset, startElement));
			multiTextEdit.addChild(new InsertEdit(endTagOffset, "</"+ELEMENT_NAME +">")); //$NON-NLS-1$ //$NON-NLS-2$
			multiTextEdit.apply(viewer.getDocument());
			Position start = new Position(startTagOffset);
			Position end = new Position(endTagOffset + startElement.length());

			try {
				viewer.getDocument().addPosition(start);
				viewer.getDocument().addPosition(end);

				// get new element node
				IDOMNode newElementNode = (IDOMNode) ContentAssistUtils.getNodeAt(viewer, startTagOffset);
				IStructuredFormatProcessor formatProcessor = new FormatProcessorXML();
				formatProcessor.formatNode(newElementNode);

				// rename new element
				apply(viewer, trigger, stateMask, start, end, ELEMENT_NAME.length());
			} finally {
				viewer.getDocument().removePosition(start);
				viewer.getDocument().removePosition(end);
			}
		}
		catch (MalformedTreeException e) {
			// log for now, unless find reason not to
			Logger.log(Logger.INFO, e.getMessage());
		}
		catch (BadLocationException e) {
			// log for now, unless find reason not to
			Logger.log(Logger.INFO, e.getMessage());
		} 
	}

	private void apply(ITextViewer viewer, char trigger, int stateMask, Position start, Position end, int length) {
		IDocument document = viewer.getDocument();
		LinkedPositionGroup group = new LinkedPositionGroup();
		try {
				group.addPosition(new LinkedPosition(document, start.offset + 1, length, 0)); // offset by 1 for <
				group.addPosition(new LinkedPosition(document, end.offset + 2, length, 1)); // offset by 2 for </
			
			if(viewer instanceof ITextViewerExtension)
				((ITextViewerExtension) viewer).setRedraw(true);

			LinkedModeModel linkedModeModel = new LinkedModeModel();
			linkedModeModel.addGroup(group);
			linkedModeModel.forceInstall();
	
			LinkedModeUI ui = new EditorLinkedModeUI(linkedModeModel, viewer);
			ui.setExitPosition(viewer, start.offset, 0, LinkedPositionGroup.NO_STOP);
			ui.enter();
	
			fSelectedRegion = ui.getSelectedRegion();
		}
		catch (BadLocationException e) {
			// log for now, unless find reason not to
			Logger.log(Logger.INFO, e.getMessage());
		}
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.text.contentassist.ICompletionProposal#getAdditionalProposalInfo()
	 */
	public String getAdditionalProposalInfo() {
		return XMLUIMessages.SurroundWithNewElementQuickAssistProposal_0;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.text.contentassist.ICompletionProposal#getDisplayString()
	 */
	public String getDisplayString() {
		return XMLUIMessages.SurroundWithNewElementQuickAssistProposal_1;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.text.contentassist.ICompletionProposal#getImage()
	 */
	public Image getImage() {
		// return JavaPluginImages.get(JavaPluginImages.IMG_CORRECTION_LOCAL);
		return XMLEditorPluginImageHelper.getInstance().getImage(XMLEditorPluginImages.IMG_OBJ_ADD_CORRECTION);
	}
}