/*******************************************************************************
 * Copyright (c) 2000, 2003 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.ui.wizards.datatransfer;

 
import java.util.*;

import org.eclipse.jface.operation.ModalContext;
import org.eclipse.ui.dialogs.FileSystemElement;

/**
 * The PopulateFilesOperation is an operation used to populate a FileSystemElement one
 * level deep rather than the whole way.
 */
public class PopulateRootOperation extends SelectFilesOperation {
/**
 * Create a new <code>PopulateFilesOperation</code>.
 * @param rootObject the object to be populated
 * @param structureProvider the object that defines how we are to populate it.
 */
public PopulateRootOperation(Object rootObject, IImportStructureProvider structureProvider) {
	super(rootObject, structureProvider);
}
/**
 * Creates and returns a <code>FileSystemElement</code> if the specified
 * file system object merits one.  The criteria for this are:
 * - if the file system object is a container then it must have either a
 *   child container or an associated file
 * - if the file system object is a file then it must have an extension
 *   suitable for selection
 */
protected FileSystemElement createElement(
	FileSystemElement parent,
	Object fileSystemObject)
	throws InterruptedException {

	//Iterate on level deep
	return createElement(parent, fileSystemObject, 2);

}
/**
 * Creates and returns a <code>FileSystemElement</code> if the specified
 * file system object merits one.  The criteria for this are:
 * - if the file system object is a container then it must have either a
 *   child container or an associated file
 * - if the file system object is a file then it must have an extension
 *   suitable for selection
 * 	recurse down for depth to populate children
 */
protected FileSystemElement createElement(
	FileSystemElement parent,
	Object fileSystemObject,
	int depth)
	throws InterruptedException {
	ModalContext.checkCanceled(monitor);
	boolean isContainer = provider.isFolder(fileSystemObject);
	String elementLabel =
		parent == null
			? provider.getFullPath(fileSystemObject)
			: provider.getLabel(fileSystemObject);

	MinimizedFileSystemElement result =
		new MinimizedFileSystemElement(elementLabel, parent, isContainer);
	result.setFileSystemObject(fileSystemObject);

	if (isContainer) {
		if (depth > 0) {
			List children = provider.getChildren(fileSystemObject);
			if (children == null)
				children = new ArrayList(1);
			Iterator childrenEnum = children.iterator();
			while (childrenEnum.hasNext()) {
				createElement(result, childrenEnum.next(), depth - 1);
			}
			result.setPopulated();
		}

	}

	return result;
}
}