/**

 * Copyright (c) 2010 Symbian Foundation and/or its subsidiary(-ies).

 * All rights reserved.

 * This component and the accompanying materials are made available

 * under the terms of the License "Eclipse Public License v1.0"

 * which accompanies this distribution, and is available

 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

 *

 * Initial Contributors:

 * Symbian Foundation - initial contribution.

 * Contributors:

 * Description:

 * Overview:

 * Details:

 * Platforms/Drives/Compatibility:

 * Assumptions/Requirement/Pre-requisites:

 * Failures and causes:

 */

package org.symbian.tools.tmw.debug.ui.actions;

import org.eclipse.debug.core.DebugPlugin;

import org.eclipse.debug.core.IExpressionManager;

import org.eclipse.debug.core.model.IWatchExpression;

import org.eclipse.debug.ui.IDebugUIConstants;

import org.eclipse.jface.action.IAction;

import org.eclipse.jface.text.ITextSelection;

import org.eclipse.jface.viewers.ISelection;

import org.eclipse.ui.IEditorActionDelegate;

import org.eclipse.ui.IEditorInput;

import org.eclipse.ui.IEditorPart;

import org.eclipse.ui.PartInitException;

import org.eclipse.ui.actions.ActionDelegate;

import org.eclipse.wst.jsdt.core.IJavaScriptUnit;

import org.eclipse.wst.jsdt.core.dom.AST;

import org.eclipse.wst.jsdt.core.dom.ASTNode;

import org.eclipse.wst.jsdt.core.dom.ASTParser;

import org.eclipse.wst.jsdt.core.dom.ASTVisitor;

import org.eclipse.wst.jsdt.core.dom.SimpleName;

import org.eclipse.wst.jsdt.internal.ui.JavaScriptPlugin;

import org.eclipse.wst.jsdt.internal.ui.javaeditor.WorkingCopyManager;

import org.symbian.tools.tmw.debug.internal.Activator;

@SuppressWarnings("restriction")

public class WatchExpression extends ActionDelegate implements IEditorActionDelegate {

    private final class FindNode extends ASTVisitor {

        private final int offset;

        private final int length;

        private ASTNode node;

        private FindNode(int offset, int length) {

            super(false);

            this.offset = offset;

            this.length = length;

        }

        @Override

        public boolean visit(SimpleName node) {

            checkNode(node);

            return true;

        }

        public void checkNode(ASTNode node) {

            final int end = node.getStartPosition() + node.getLength();

            if (node.getStartPosition() <= offset && end >= offset + length) {

                this.node = node;

            }

        }

        @Override

        public void postVisit(ASTNode node) {

            if (this.node == null) {

                checkNode(node);

            }

        }

        public ASTNode getNode() {

            return node;

        }

    }

    private IEditorPart targetEditor;

    public void setActiveEditor(IAction action, IEditorPart targetEditor) {

        this.targetEditor = targetEditor;

    }

    @Override

    public void run(IAction action) {

        ISelection selection = targetEditor.getEditorSite().getSelectionProvider().getSelection();

        if (selection instanceof ITextSelection) {

            final ITextSelection textSelection = (ITextSelection) selection;

            final WorkingCopyManager manager = JavaScriptPlugin.getDefault().getWorkingCopyManager();

            final IEditorInput editorInput = targetEditor.getEditorInput();

            final IJavaScriptUnit workingCopy = manager.getWorkingCopy(editorInput);

            final ASTParser parser = ASTParser.newParser(AST.JLS3);

            parser.setSource(workingCopy);

            final ASTNode ast = parser.createAST(null);

            final FindNode visitor = new FindNode(textSelection.getOffset(), textSelection.getLength());

            ast.accept(visitor);

            final ASTNode node = visitor.getNode();

            if (node != null) {

                final String jsString;

                if (node.getNodeType() == ASTNode.SIMPLE_NAME) {

                    switch (node.getParent().getNodeType()) {

                    case ASTNode.FIELD_ACCESS:

                    case ASTNode.FUNCTION_INVOCATION:

                        jsString = node.getParent().toString();

                        break;

                    default:

                        jsString = node.toString();

                        break;

                    }

                } else {

                    jsString = node.toString();

                }

                IExpressionManager expressionManager = DebugPlugin.getDefault().getExpressionManager();

                IWatchExpression expression = expressionManager.newWatchExpression(jsString);

                expressionManager.addExpression(expression);

                try {

                    targetEditor.getSite().getPage().showView(IDebugUIConstants.ID_EXPRESSION_VIEW);

                } catch (PartInitException e) {

                    Activator.log(e);

                }

            }

        }

    }

}