/*******************************************************************************
 * Copyright (c) 2000, 2017 IBM Corporation and others.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 * 
 * SPDX-License-Identifier: EPL-2.0
 *
 *******************************************************************************/
package org.eclipse.dltk.internal.ui.actions;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.dltk.core.IModelElement;
import org.eclipse.dltk.core.ISourceReference;
import org.eclipse.dltk.core.ModelException;
import org.eclipse.dltk.internal.ui.editor.EditorUtility;
import org.eclipse.dltk.ui.ModelElementLabelProvider;
import org.eclipse.jface.window.Window;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.PartInitException;
import org.eclipse.ui.dialogs.ElementListSelectionDialog;

public class OpenActionUtil {

	private OpenActionUtil() {
		// no instance.
	}

	/**
	 * Opens the editor on the given element and subsequently selects it.
	 */
	public static void open(Object element)
			throws ModelException, PartInitException {
		open(element, true);
	}

	/**
	 * Opens the editor on the given element and subsequently selects it.
	 */
	public static void open(Object element, boolean activate)
			throws ModelException, PartInitException {
		IEditorPart part = EditorUtility.openInEditor(element, activate);
		if (element instanceof IModelElement)
			EditorUtility.revealInEditor(part, (IModelElement) element);
	}

	/**
	 * Filters out source references from the given code resolve results. A
	 * utility method that can be called by subclasses.
	 */
	public static List<IModelElement> filterResolveResults(
			IModelElement[] codeResolveResults) {
		int nResults = codeResolveResults.length;
		List<IModelElement> refs = new ArrayList<>(nResults);
		for (int i = 0; i < nResults; i++) {
			if (codeResolveResults[i] instanceof ISourceReference)
				refs.add(codeResolveResults[i]);
		}
		return refs;
	}

	public static Object select(Object[] elements, Shell shell, String title,
			String message) {

		int nResults = elements.length;

		if (nResults == 0)
			return null;

		if (nResults == 1)
			return elements[0];

		int flags = ModelElementLabelProvider.SHOW_DEFAULT
				// | ModelElementLabelProvider.SHOW_QUALIFIED
				| ModelElementLabelProvider.SHOW_ROOT
				| ModelElementLabelProvider.SHOW_FILE_QUALIFIED;

		ElementListSelectionDialog dialog = new ElementListSelectionDialog(
				shell, new ModelElementLabelProvider(flags));
		dialog.setTitle(title);
		dialog.setMessage(message);
		dialog.setElements(elements);

		if (dialog.open() == Window.OK) {
			Object[] selection = dialog.getResult();
			if (selection != null && selection.length > 0) {
				return selection[0];
			}
		}
		return null;
	}

	/**
	 * Shows a dialog for resolving an ambiguous script element. Utility method
	 * that can be called by subclasses.
	 */
	public static IModelElement selectModelElement(IModelElement[] elements,
			Shell shell, String title, String message) {
		Object selection = select(elements, shell, title, message);
		if (selection instanceof IModelElement) {
			return (IModelElement) selection;
		}
		return null;
	}
}