PartialModelEditor.java

package org.eclipse.xtext.gmf.glue.partialEditing;

import java.util.Collections;

import org.eclipse.emf.ecore.EObject;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.ISynchronizable;
import org.eclipse.jface.text.source.AnnotationModel;
import org.eclipse.jface.text.source.SourceViewer;
import org.eclipse.xtext.gmf.glue.edit.part.IXtextEMFReconciler;
import org.eclipse.xtext.resource.XtextResource;
import org.eclipse.xtext.ui.editor.model.XtextDocument;
import org.eclipse.xtext.util.StringInputStream;

/**
 * 
 */
public class PartialModelEditor {

	protected final SourceViewer viewer;
	protected final boolean insertLineBreaks;
	protected final ISyntheticResourceProvider resourceProvider;
	protected EObject semanticElement ;
	protected IXtextEMFReconciler modelReconciler ;
	//private final Injector xtextInjector ;

	/**
	 * @param viewer 
	 * @param resourceProvider 
	 * @param insertLineBreaks 
	 * @param semanticElement 
	 * @param modelReconciler 
	 *
	 */
	public PartialModelEditor(SourceViewer viewer, 
							  ISyntheticResourceProvider resourceProvider, 
							  boolean insertLineBreaks,
							  EObject semanticElement,
							  IXtextEMFReconciler modelReconciler) {
		//this.xtextInjector = xtextInjector ;
		this.viewer = viewer;
		this.resourceProvider = resourceProvider;
		this.insertLineBreaks = insertLineBreaks;
		this.semanticElement = semanticElement ;
		this.modelReconciler = modelReconciler ;
	}
	
	/**
	 * @param document 
	 * @param prefix 
	 * @param editablePart 
	 * @param suffix 
	 *
	 */
	public void setModel(XtextDocument document, String prefix, String editablePart, String suffix) {
		if (insertLineBreaks) {
			String delimiter = document.getLegalLineDelimiters()[0];
			prefix = prefix + delimiter;
			suffix = delimiter + suffix;
		}
		String model = prefix + editablePart + suffix;
		document.set(model);
		XtextResource resource = createResource(model);
		document.setInput(resource);
		AnnotationModel annotationModel = new AnnotationModel();
		if (document instanceof ISynchronizable) {
			Object lock= ((ISynchronizable)document).getLockObject();
			if (lock == null) {
				lock= new Object();
				((ISynchronizable)document).setLockObject(lock);
			}
			((ISynchronizable) annotationModel).setLockObject(lock);
		}
		viewer.setDocument(document, annotationModel, prefix.length(), editablePart.length());
		viewer.getUndoManager().reset();
	}
	
	/**
	 * @param content 
	 * @return XtextResource
	 *
	 */
	public XtextResource createResource(String content) {
		XtextResource result = resourceProvider.createResource();
		try {
			result.load(new StringInputStream(content, result.getEncoding()), Collections.emptyMap());
		} catch (Exception e) {
			throw new RuntimeException(e);
		}
		return result;
	}
	
	/**
	 * @param prefix 
	 * @param editablePart 
	 * @param suffix 
	 *
	 */
	public void updateModel(String prefix, String editablePart, String suffix) {
		IDocument document= viewer.getDocument();
		if (insertLineBreaks) {
			String delimiter = document.getLegalLineDelimiters()[0];
			prefix = prefix + delimiter;
			suffix = delimiter + suffix;
		}
		String model = prefix + editablePart + suffix;
		viewer.setRedraw(false);
		viewer.getUndoManager().disconnect();
		document.set(model);
		viewer.setVisibleRegion(prefix.length(), editablePart.length());
		viewer.getUndoManager().connect(viewer);
		viewer.setRedraw(true);
	}
	
	/**
	 * @param prefix 
	 *
	 */
	public void updatePrefix(String prefix) {
		try {
			IDocument document= viewer.getDocument();
			IRegion visibleRegion = viewer.getVisibleRegion();
			String editablePart = document.get(visibleRegion.getOffset(), visibleRegion.getLength());
			int suffixOffset = visibleRegion.getOffset() + visibleRegion.getLength();
			String suffix = "";
			if (document.getLength() - suffixOffset > 0) {
				suffix = document.get(suffixOffset, document.getLength() - suffixOffset);	
				if (insertLineBreaks) {
					String delimiter = document.getLegalLineDelimiters()[0];
					suffix = suffix.substring(delimiter.length());
				}
			}
			updateModel(prefix, editablePart, suffix);
		} catch(BadLocationException e) {
			throw new RuntimeException(e);
		}
	}

	/**
	 * @return String
	 *
	 */
	public String getEditablePart() {
		IDocument doc= viewer.getDocument();
		IRegion visible= viewer.getVisibleRegion();
		try {
			return doc.get(visible.getOffset(), visible.getLength());
		} catch (BadLocationException e) {
			return ""; //$NON-NLS-1$
		}
	}
	
	/**
	 * @return String
	 *
	 */
	public String getSerializedModel() {
		return viewer.getDocument().get();
	}
	
}