content: /*******************************************************************************
   * Copyright (c) 2000, 2008 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
   *******************************************************************************/
  package org.eclipse.wst.jsdt.internal.ui.javaeditor;
  
  import org.eclipse.jface.text.IDocument;
  import org.eclipse.jface.text.TextSelection;
  import org.eclipse.wst.jsdt.core.IJavaScriptElement;
  import org.eclipse.wst.jsdt.core.IJavaScriptUnit;
  import org.eclipse.wst.jsdt.core.JavaScriptModelException;
  import org.eclipse.wst.jsdt.core.dom.ASTNode;
  import org.eclipse.wst.jsdt.core.dom.AbstractTypeDeclaration;
  import org.eclipse.wst.jsdt.core.dom.BodyDeclaration;
  import org.eclipse.wst.jsdt.core.dom.JavaScriptUnit;
  import org.eclipse.wst.jsdt.core.dom.SingleVariableDeclaration;
  import org.eclipse.wst.jsdt.core.dom.VariableDeclarationFragment;
  import org.eclipse.wst.jsdt.internal.corext.dom.Selection;
  import org.eclipse.wst.jsdt.internal.corext.dom.SelectionAnalyzer;
  import org.eclipse.wst.jsdt.internal.ui.JavaScriptPlugin;
  import org.eclipse.wst.jsdt.internal.ui.actions.SelectionConverter;
  
  /**
   * A special text selection that gives access to the resolved and
   * enclosing element.
   */
  public class JavaTextSelection extends TextSelection {
  
  	private IJavaScriptElement fElement;
  	private IJavaScriptElement[] fResolvedElements;
  
  	private boolean fEnclosingElementRequested;
  	private IJavaScriptElement fEnclosingElement;
  
  	private boolean fPartialASTRequested;
  	private JavaScriptUnit fPartialAST;
  
  	private boolean fNodesRequested;
  	private ASTNode[] fSelectedNodes;
  	private ASTNode fCoveringNode;
  
  	private boolean fInMethodBodyRequested;
  	private boolean fInMethodBody;
  
  	private boolean fInClassInitializerRequested;
  	private boolean fInClassInitializer;
  
  	private boolean fInVariableInitializerRequested;
  	private boolean fInVariableInitializer;
  
  	/**
  	 * Creates a new text selection at the given offset and length.
  	 */
  	public JavaTextSelection(IJavaScriptElement element, IDocument document, int offset, int length) {
  		super(document, offset, length);
  		fElement= element;
  	}
  
  	/**
  	 * Resolves the <code>IJavaScriptElement</code>s at the current offset. Returns
  	 * an empty array if the string under the offset doesn't resolve to a
  	 * <code>IJavaScriptElement</code>.
  	 *
  	 * @return the resolved java elements at the current offset
  	 * @throws JavaScriptModelException passed from the underlying code resolve API
  	 */
  	public IJavaScriptElement[] resolveElementAtOffset() throws JavaScriptModelException {
  		if (fResolvedElements != null)
  			return fResolvedElements;
  		// long start= System.currentTimeMillis();
  		fResolvedElements= SelectionConverter.codeResolve(fElement, this);
  		// System.out.println("Time resolving element: " + (System.currentTimeMillis() - start));
  		return fResolvedElements;
  	}
  
  	public IJavaScriptElement resolveEnclosingElement() throws JavaScriptModelException {
  		if (fEnclosingElementRequested)
  			return fEnclosingElement;
  		fEnclosingElementRequested= true;
  		fEnclosingElement= SelectionConverter.resolveEnclosingElement(fElement, this);
  		return fEnclosingElement;
  	}
  
  	public JavaScriptUnit resolvePartialAstAtOffset() {
  		if (fPartialASTRequested)
  			return fPartialAST;
  		fPartialASTRequested= true;
  		if (! (fElement instanceof IJavaScriptUnit))
  			return null;
  		// long start= System.currentTimeMillis();
  		fPartialAST= JavaScriptPlugin.getDefault().getASTProvider().getAST(fElement, ASTProvider.WAIT_YES, null);
  		// System.out.println("Time requesting partial AST: " + (System.currentTimeMillis() - start));
  		return fPartialAST;
  	}
  
  	public ASTNode[] resolveSelectedNodes() {
  		if (fNodesRequested)
  			return fSelectedNodes;
  		fNodesRequested= true;
  		JavaScriptUnit root= resolvePartialAstAtOffset();
  		if (root == null)
  			return null;
  		Selection ds= Selection.createFromStartLength(getOffset(), getLength());
  		SelectionAnalyzer analyzer= new SelectionAnalyzer(ds, false);
  		root.accept(analyzer);
  		fSelectedNodes= analyzer.getSelectedNodes();
  		fCoveringNode= analyzer.getLastCoveringNode();
  		return fSelectedNodes;
  	}
  
  	public ASTNode resolveCoveringNode() {
  		if (fNodesRequested)
  			return fCoveringNode;
  		resolveSelectedNodes();
  		return fCoveringNode;
  	}
  
  	public boolean resolveInMethodBody() {
  		if (fInMethodBodyRequested)
  			return fInMethodBody;
  		fInMethodBodyRequested= true;
  		resolveSelectedNodes();
  		ASTNode node= getStartNode();
  		if (node == null) {
  			fInMethodBody= true;
  		} else {
  			while (node != null) {
  				int nodeType= node.getNodeType();
  				if (nodeType == ASTNode.BLOCK && node.getParent() instanceof BodyDeclaration) {
  					fInMethodBody= node.getParent().getNodeType() == ASTNode.FUNCTION_DECLARATION;
  					break;
  				} else if (nodeType == ASTNode.ANONYMOUS_CLASS_DECLARATION) {
  					fInMethodBody= false;
  					break;
  				}
  				node= node.getParent();
  			}
  		}
  		return fInMethodBody;
  	}
  
  	public boolean resolveInClassInitializer() {
  		if (fInClassInitializerRequested)
  			return fInClassInitializer;
  		fInClassInitializerRequested= true;
  		resolveSelectedNodes();
  		ASTNode node= getStartNode();
  		if (node == null) {
  			fInClassInitializer= true;
  		} else {
  			while (node != null) {
  				int nodeType= node.getNodeType();
  				if (node instanceof AbstractTypeDeclaration) {
  					fInClassInitializer= false;
  					break;
  				} else if (nodeType == ASTNode.ANONYMOUS_CLASS_DECLARATION) {
  					fInClassInitializer= false;
  					break;
  				} else if (nodeType == ASTNode.INITIALIZER) {
  					fInClassInitializer= true;
  					break;
  				}
  				node= node.getParent();
  			}
  		}
  		return fInClassInitializer;
  	}
  
  	public boolean resolveInVariableInitializer() {
  		if (fInVariableInitializerRequested)
  			return fInVariableInitializer;
  		fInVariableInitializerRequested= true;
  		resolveSelectedNodes();
  		ASTNode node= getStartNode();
  		ASTNode last= null;
  		while (node != null) {
  			int nodeType= node.getNodeType();
  			if (node instanceof AbstractTypeDeclaration) {
  				fInVariableInitializer= false;
  				break;
  			} else if (nodeType == ASTNode.ANONYMOUS_CLASS_DECLARATION) {
  				fInVariableInitializer= false;
  				break;
  			} else if (nodeType == ASTNode.VARIABLE_DECLARATION_FRAGMENT &&
  					   ((VariableDeclarationFragment)node).getInitializer() == last) {
  				fInVariableInitializer= true;
  				break;
  			} else if (nodeType == ASTNode.SINGLE_VARIABLE_DECLARATION &&
  				       ((SingleVariableDeclaration)node).getInitializer() == last) {
  				fInVariableInitializer= true;
  				break;
  			}
  			last= node;
  			node= node.getParent();
  		}
  		return fInVariableInitializer;
  	}
  
  	private ASTNode getStartNode() {
  		if (fSelectedNodes != null && fSelectedNodes.length > 0)
  			return fSelectedNodes[0];
  		else
  			return fCoveringNode;
  	}
  }
  