/*******************************************************************************
 * Copyright (c) 2004, 2012 QNX Software Systems and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 * QNX Software Systems - Initial API and implementation
 *******************************************************************************/
package org.eclipse.cdt.debug.internal.ui.actions;

import org.eclipse.cdt.debug.ui.CDebugUIPlugin;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.debug.core.DebugPlugin;
import org.eclipse.debug.core.model.IDebugElement;
import org.eclipse.debug.core.model.IWatchExpression;
import org.eclipse.debug.ui.DebugUITools;
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.jface.viewers.ISelectionProvider;
import org.eclipse.jface.window.Window;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.ui.IEditorActionDelegate;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.IWorkbenchPage;
import org.eclipse.ui.IWorkbenchPart;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.PartInitException;
import org.eclipse.ui.actions.ActionDelegate;

/**
 * The "Add Expression" action contribution to editors.
 */
public class AddExpressionEditorActionDelegate extends ActionDelegate implements IEditorActionDelegate {

	private IEditorPart fEditorPart;

	/* (non-Javadoc)
	 * @see org.eclipse.ui.IEditorActionDelegate#setActiveEditor(org.eclipse.jface.action.IAction, org.eclipse.ui.IEditorPart)
	 */
	@Override
	public void setActiveEditor(IAction action, IEditorPart targetEditor) {
		setEditorPart(targetEditor);
	}

	private IEditorPart getEditorPart() {
		return fEditorPart;
	}

	private void setEditorPart(IEditorPart editorPart) {
		fEditorPart = editorPart;
	}

	@Override
	public void run(IAction action) {
		String text = getSelectedText();
		ExpressionDialog dlg = new ExpressionDialog(getShell(), text);
		if (dlg.open() != Window.OK)
			return;
		createExpression(dlg.getExpression());
		activateExpressionView();
	}

	private String getSelectedText() {
		ISelection selection = getTargetSelection();
		if (selection != null && selection instanceof ITextSelection) {
			return ((ITextSelection) selection).getText().replaceAll("(\\r\\n|\\n|\\t| )+", " ").trim(); //$NON-NLS-1$ //$NON-NLS-2$;
		}
		return ""; //$NON-NLS-1$
	}

	protected ISelection getTargetSelection() {
		IWorkbenchPart part = getEditorPart();
		if (part != null) {
			ISelectionProvider provider = part.getSite().getSelectionProvider();
			if (provider != null) {
				return provider.getSelection();
			}
		}
		return null;
	}

	private void createExpression(String text) {
		IWatchExpression watchExpression = DebugPlugin.getDefault().getExpressionManager().newWatchExpression(text);
		DebugPlugin.getDefault().getExpressionManager().addExpression(watchExpression);
		IAdaptable context = DebugUITools.getDebugContext();
		if (context instanceof IDebugElement)
			watchExpression.setExpressionContext((IDebugElement) context);
	}

	protected Shell getShell() {
		return (getEditorPart() != null) ? getEditorPart().getSite().getShell()
				: CDebugUIPlugin.getActiveWorkbenchShell();
	}

	private void activateExpressionView() {
		IWorkbenchWindow window = CDebugUIPlugin.getActiveWorkbenchWindow();
		if (window != null) {
			IWorkbenchPage page = window.getActivePage();
			if (page != null) {
				try {
					page.showView(IDebugUIConstants.ID_EXPRESSION_VIEW);
				} catch (PartInitException e) {
				}
			}
		}
	}
}
