/*******************************************************************************
 * 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.views.navigator;

import java.util.Iterator;
import java.util.List;

import org.eclipse.core.resources.IContainer;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.IPath;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.jface.util.Assert;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.swt.SWTError;
import org.eclipse.swt.dnd.*;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.actions.SelectionListenerAction;
import org.eclipse.ui.help.WorkbenchHelp;
import org.eclipse.ui.internal.WorkbenchMessages;
import org.eclipse.ui.part.ResourceTransfer;

/**
 * Standard action for copying the currently selected resources to the clipboard.
 * <p>
 * This class may be instantiated; it is not intended to be subclassed.
 * </p>
 * 
 * @since 2.0
 */
/*package*/ class CopyAction extends SelectionListenerAction {

	/**
	 * The id of this action.
	 */
	public static final String ID = PlatformUI.PLUGIN_ID + ".CopyAction"; //$NON-NLS-1$
	
	/**
	 * The shell in which to show any dialogs.
	 */
	private Shell shell;
	
	/**
	 * System clipboard
	 */
	private Clipboard clipboard;

	/**
	 * Associated paste action. May be <code>null</code>
	 */
	private PasteAction pasteAction;

/**
 * Creates a new action.
 *
 * @param shell the shell for any dialogs
 * @param clipboard a platform clipboard
 */
public CopyAction(Shell shell, Clipboard clipboard) {
	super(ResourceNavigatorMessages.getString("CopyAction.title")); //$NON-NLS-1$
	Assert.isNotNull(shell);
	Assert.isNotNull(clipboard);
	this.shell = shell;
	this.clipboard = clipboard;
	setToolTipText(ResourceNavigatorMessages.getString("CopyAction.toolTip")); //$NON-NLS-1$
	setId(CopyAction.ID);
	WorkbenchHelp.setHelp(this, INavigatorHelpContextIds.COPY_ACTION);
}
/**
 * Creates a new action.
 *
 * @param shell the shell for any dialogs
 * @param clipboard a platform clipboard
 * @param pasteAction a paste action
 * 
 * @since 2.0
 */
public CopyAction(Shell shell, Clipboard clipboard, PasteAction pasteAction) {
	this(shell, clipboard);
	this.pasteAction = pasteAction;
}	
/**
 * The <code>CopyAction</code> implementation of this method defined 
 * on <code>IAction</code> copies the selected resources to the 
 * clipboard.
 */
public void run(){	
	List selectedResources = getSelectedResources();
	IResource[] resources = (IResource[]) selectedResources.toArray(new IResource[selectedResources.size()]);
	
	// Get the file names and a string representation
	final int length = resources.length;
	int actualLength = 0;	
	String[] fileNames = new String[length];
	StringBuffer buf = new StringBuffer();
	for (int i = 0; i < length; i++) {
		IPath location = resources[i].getLocation();
		// location may be null. See bug 29491.
		if (location != null)
			fileNames[actualLength++] = location.toOSString();
		if (i > 0)
			buf.append("\n"); //$NON-NLS-1$
		buf.append(resources[i].getName());
	}
	// was one or more of the locations null?
	if (actualLength < length) {
		String[] tempFileNames = fileNames;
		fileNames = new String[actualLength];
		for (int i = 0; i < actualLength; i++)
			fileNames[i] = tempFileNames[i];
	}
	setClipboard(resources, fileNames, buf.toString());
			
	// update the enablement of the paste action
	// workaround since the clipboard does not suppot callbacks
	if (pasteAction != null && pasteAction.getStructuredSelection() != null) 
		pasteAction.selectionChanged(pasteAction.getStructuredSelection());
}
/**
 * Set the clipboard contents. Prompt to retry if clipboard is busy.
 * 
 * @param resources the resources to copy to the clipboard
 * @param fileNames file names of the resources to copy to the clipboard
 * @param names string representation of all names
 */
private void setClipboard(IResource[] resources, String[] fileNames, String names) {
	try {
		// set the clipboard contents
		if (fileNames.length > 0) {
			clipboard.setContents(
				new Object[]{
					resources, 
					fileNames, 
					names}, 
				new Transfer[]{
					ResourceTransfer.getInstance(), 
					FileTransfer.getInstance(), 
					TextTransfer.getInstance()});
		} else {
			clipboard.setContents(
				new Object[]{
					resources, 
					names}, 
				new Transfer[]{
					ResourceTransfer.getInstance(), 
					TextTransfer.getInstance()});
		}
	} catch (SWTError e){
		if (e.code != DND.ERROR_CANNOT_SET_CLIPBOARD)
			throw e;
		if (MessageDialog.openQuestion(shell, WorkbenchMessages.getString("CopyToClipboardProblemDialog.title"), WorkbenchMessages.getString("CopyToClipboardProblemDialog.message"))) //$NON-NLS-1$ //$NON-NLS-2$
			setClipboard(resources, fileNames, names);
	}	
}
/**
 * The <code>CopyAction</code> implementation of this
 * <code>SelectionListenerAction</code> method enables this action if 
 * one or more resources of compatible types are selected.
 */
protected boolean updateSelection(IStructuredSelection selection) {
	if (!super.updateSelection(selection))
		return false;
	
	if (getSelectedNonResources().size() > 0) 
		return false;

	List selectedResources = getSelectedResources();
	if (selectedResources.size() == 0)
		return false;
	
	boolean projSelected = selectionIsOfType(IResource.PROJECT);
	boolean fileFoldersSelected = selectionIsOfType(IResource.FILE | IResource.FOLDER);
	if (!projSelected && !fileFoldersSelected)
		return false;

	// selection must be homogeneous
	if (projSelected && fileFoldersSelected)
		return false;
	
	// must have a common parent	
	IContainer firstParent = ((IResource) selectedResources.get(0)).getParent();
	if (firstParent == null) 
		return false;

	Iterator resourcesEnum = selectedResources.iterator();
	while (resourcesEnum.hasNext()) {
		IResource currentResource = (IResource) resourcesEnum.next();
		if (!currentResource.getParent().equals(firstParent))
			return false;
		// resource location must exist
		if (currentResource.getLocation() == null)
			return false;
	}
	
	return true;
}

}