/*******************************************************************************
 * Copyright (c) 2000, 2008 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.wst.jsdt.internal.ui.wizards.buildpaths;

import java.io.File;

import org.eclipse.core.runtime.IStatus;
import org.eclipse.jface.viewers.ITreeContentProvider;
import org.eclipse.jface.viewers.LabelProvider;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.jface.viewers.ViewerComparator;
import org.eclipse.jface.viewers.ViewerFilter;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.ui.ISharedImages;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.dialogs.ElementTreeSelectionDialog;
import org.eclipse.ui.dialogs.ISelectionStatusValidator;
import org.eclipse.wst.jsdt.internal.ui.JavaScriptPlugin;
import org.eclipse.wst.jsdt.internal.ui.JavaPluginImages;
import org.eclipse.wst.jsdt.internal.ui.dialogs.StatusInfo;

/**
 * Selection dialog to select a JAR on the file system.
 * Set input to a java.io.File that point to folder.
 */
public class JARFileSelectionDialog extends ElementTreeSelectionDialog {
	
	/**
	 * Constructor for JARFileSelectionDialog.
	 * @param parent parent shell
	 * @param multiSelect specifies if selecting multiple elements is allowed
	 * @param acceptFolders specifies if folders can be selected as well
	 */
	public JARFileSelectionDialog(Shell parent, boolean multiSelect, boolean acceptFolders) {
		super(parent, new FileLabelProvider(), new FileContentProvider());
		setComparator(new FileViewerComparator());
		addFilter(new FileArchiveFileFilter(acceptFolders));
		setValidator(new FileSelectionValidator(multiSelect, acceptFolders));
		setHelpAvailable(false);
	}
	
	private static boolean isArchive(File file) {
		String name= file.getName();
		int detIndex= name.lastIndexOf('.');
		return (detIndex != -1 && ArchiveFileFilter.isArchiveFileExtension(name.substring(detIndex + 1)));
	}		

	private static class FileLabelProvider extends LabelProvider {
		private final Image IMG_FOLDER= PlatformUI.getWorkbench().getSharedImages().getImage(ISharedImages.IMG_OBJ_FOLDER);
		private final Image IMG_JAR=  JavaScriptPlugin.getDefault().getImageRegistry().get(JavaPluginImages.IMG_OBJS_EXTJAR);
	
		public Image getImage(Object element) {
			if (element instanceof File) {
				File curr= (File) element;
				if (curr.isDirectory()) {
					return IMG_FOLDER;
				} else {
					return IMG_JAR;
				}
			}
			return null;
		}
	
		public String getText(Object element) {
			if (element instanceof File) {
				return ((File) element).getName();
			}
			return super.getText(element);
		}
	}
	
	private static class FileContentProvider implements ITreeContentProvider {
		
		private final Object[] EMPTY= new Object[0];
	
		public Object[] getChildren(Object parentElement) {
			if (parentElement instanceof File) {
				File[] children= ((File) parentElement).listFiles();
				if (children != null) {
					return children;
				}
			}
			return EMPTY;
		}
	
		public Object getParent(Object element) {
			if (element instanceof File) {
				return ((File) element).getParentFile();
			}
			return null;
		}
	
		public boolean hasChildren(Object element) {
			return getChildren(element).length > 0;
		}
	
		public Object[] getElements(Object element) {
			return getChildren(element);
		}
	
		public void dispose() {
		}
	
		public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
		}
	
	}
	
	private static class FileArchiveFileFilter extends ViewerFilter {
		private final boolean fAcceptFolders;

		public FileArchiveFileFilter(boolean acceptFolders) {
			fAcceptFolders= acceptFolders;
		}

		public boolean select(Viewer viewer, Object parent, Object element) {
			if (element instanceof File) {
				File file= (File) element;
				if (file.isFile()) {
					return isArchive(file);
				} else if (fAcceptFolders) {
					return true;
				} else {
					File[] listFiles= file.listFiles();
					if (listFiles != null) {
						for (int i= 0; i < listFiles.length; i++) {
							if (select(viewer, file, listFiles[i])) {
								return true;
							}
						}
					}
				}
			}
			return false;
		}		
	}
	
	private static class FileViewerComparator extends ViewerComparator {
		public int category(Object element) {
			if (element instanceof File) {
				if (((File) element).isFile()) {
					return 1;
				}
			}
			return 0;
		}
	}
	
	private static class FileSelectionValidator implements ISelectionStatusValidator {
		private boolean fMultiSelect;
		private boolean fAcceptFolders;
		
		public FileSelectionValidator(boolean multiSelect, boolean acceptFolders) {
			fMultiSelect= multiSelect;
			fAcceptFolders= acceptFolders;
		}
		
		public IStatus validate(Object[] selection) {
			int nSelected= selection.length;
			if (nSelected == 0 || (nSelected > 1 && !fMultiSelect)) {
				return new StatusInfo(IStatus.ERROR, "");  //$NON-NLS-1$
			}
			for (int i= 0; i < selection.length; i++) {
				Object curr= selection[i];
				if (curr instanceof File) {
					File file= (File) curr;
					if (!fAcceptFolders && !file.isFile()) {
						return new StatusInfo(IStatus.ERROR, "");  //$NON-NLS-1$
					}
				}
			}
			return new StatusInfo();
		}
	}	


}