/*******************************************************************************
 *  Copyright (c) 2012 Google, Inc.
 *  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:
 *  Google, Inc. - initial API and implementation
 *******************************************************************************/
package com.windowtester.runtime.util;

import org.eclipse.core.runtime.*;
import java.io.*;
import java.net.*;

/**
 * The class <code>URLUtilities</code> defines utility methods for working with
 * URL's.
 * <p>
  * 
 * @author Brian Wilkerson
 * @version $Revision$
 */
public class URLUtilities
{
	////////////////////////////////////////////////////////////////////////////
	//
	// Constructors
	//
	////////////////////////////////////////////////////////////////////////////

	/**
	 * Prevent the creation of instances of this class.
	 */
	private URLUtilities()
	{
	}

	////////////////////////////////////////////////////////////////////////////
	//
	// Transformation
	//
	////////////////////////////////////////////////////////////////////////////

	/**
	 * Return a URL which is the local equivalent of the give URL. This method
	 * is expected to be used with the plug-in-relative URLs returned by
	 * IPluginDescriptor, Bundle.getEntry() and Platform.find(). If the
	 * specified URL is not a plug-in-relative URL, it is returned as-is. If
	 * the specified URL is a plug-in-relative URL of a file (including a .jar
	 * archive), it is returned as a locally-accessible URL using "file:" or
	 * "jar:file:" protocol (caching the file locally, if required). If the
	 * specified URL is a plug-in-relative URL of a directory, an exception is
	 * thrown.
	 *
	 * @param url original plug-in-relative URL
	 *
	 * @return the resolved URL
	 *
	 * @throws IOException
	 *         if it is unable to resolve URL
	 */
	public static URL toFileURL(URL url)
		throws IOException
	{
		/* $codepro.preprocessor.if version >= 3.2 $*/
		return FileLocator.toFileURL(url);
		/*$codepro.preprocessor.elseif version < 3.2 $ 
		return Platform.asLocalURL(url);
		 $codepro.preprocessor.endif $ */
	}

	////////////////////////////////////////////////////////////////////////////
	//
	// Encoding
	//
	////////////////////////////////////////////////////////////////////////////

	/**
	 * Encode the given URL so that it is appropriate for use as a URI.
	 *
	 * @param url the URL to be encoded
	 *
	 * @return the encoded form of the URL
	 */
	public static String encodeURL(String url)
	{
		int length;
//		boolean translateColon;
		StringBuffer buffer;
		char currentChar;

		length = url.length();
//		translateColon = false;
		buffer = new StringBuffer(length + 20);
		for (int i = 0; i < length; i++) {
			currentChar = url.charAt(i);
			if (currentChar == ' ') {
				buffer.append("%20");
//			} else if (currentChar == ':') {
//				if (translateColon) {
//					buffer.append("%3A");
//				} else {
//					translateColon = true;
//					buffer.append(currentChar);
//				}
			} else {
				buffer.append(currentChar);
			}
		}
		return buffer.toString();
	}
}