/*******************************************************************************
 * Copyright (c) 2000, 2004 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.ui.wizards.datatransfer;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

/**
 * This class provides information regarding the structure and
 * content of specified file system File objects.
 */
public class FileSystemStructureProvider implements IImportStructureProvider {

    /**
     * Holds a singleton instance of this class.
     */
    public final static FileSystemStructureProvider INSTANCE = new FileSystemStructureProvider();

    /**
     * Creates an instance of <code>FileSystemStructureProvider</code>.
     */
    private FileSystemStructureProvider() {
        super();
    }

    /* (non-Javadoc)
     * Method declared on IImportStructureProvider
     */
    public List getChildren(Object element) {
        File folder = (File) element;
        String[] children = folder.list();
        int childrenLength = children == null ? 0 : children.length;
        List result = new ArrayList(childrenLength);

        for (int i = 0; i < childrenLength; i++)
            result.add(new File(folder, children[i]));

        return result;
    }

    /* (non-Javadoc)
     * Method declared on IImportStructureProvider
     */
    public InputStream getContents(Object element) {
        try {
            return new FileInputStream((File) element);
        } catch (FileNotFoundException e) {
            return null;
        }
    }

    /* (non-Javadoc)
     * Method declared on IImportStructureProvider
     */
    public String getFullPath(Object element) {
        return ((File) element).getPath();
    }

    /* (non-Javadoc)
     * Method declared on IImportStructureProvider
     */
    public String getLabel(Object element) {

        //Get the name - if it is empty then return the path as it is a file root
        File file = (File) element;
        String name = file.getName();
        if (name.length() == 0)
            return file.getPath();
        else
            return name;
    }

    /* (non-Javadoc)
     * Method declared on IImportStructureProvider
     */
    public boolean isFolder(Object element) {
        return ((File) element).isDirectory();
    }
}