/*******************************************************************************
* Copyright (c) 2004, 2005 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.css.core.internal.util;
import java.io.File;
import java.net.MalformedURLException;
import java.net.URL;
import org.eclipse.wst.sse.core.internal.util.PathHelper;
/**
* Hyperlink manager. Proved useful services like link conversion An utility
* class to help other parsre modules to convert links
*/
public class URLHelper {
private static final String FILE_PROTOCOL_SEARCH_SIG = "file:/";//$NON-NLS-1$
private static final String FILE_PROTOCOL_SIG = "file:///";//$NON-NLS-1$
private static String RELATIVE_PATH_SIG = "..";//$NON-NLS-1$
private static final String FORWARD_SLASH = "/";//$NON-NLS-1$
private URL fBaseUrl = null; // base url. assumed to a absulute url
private String fBaseUrlString = null;
private URL fDocRoot = null;
private String fDocRootString = null;
public URLHelper(String baseUrl) {
initialize(baseUrl, null);
}
public URLHelper(String baseUrl, String docRoot) {
initialize(baseUrl, docRoot);
}
/**
* Special adujust for file url
*/
public String adjustFileProtocolUrl(String url) {
if (url.startsWith(FILE_PROTOCOL_SEARCH_SIG)) {
url = FILE_PROTOCOL_SIG + url.substring(FILE_PROTOCOL_SEARCH_SIG.length());
}
return url;
}
private String convert(String url, URL baseUrl, String urlString) {
String absUrl = url;
if (baseUrl != null) {
try {
// do special thing file protocol
if (baseUrl.getProtocol().equalsIgnoreCase("file")) {//$NON-NLS-1$
// remove the fist
if (url.startsWith("/"))//$NON-NLS-1$
url = url.substring(1);
// empty string causes malformed exception
String tempUrl = url;
if ("".equals(url))//$NON-NLS-1$
tempUrl = " ";//$NON-NLS-1$
URL newUrl = new URL(baseUrl, tempUrl);
// do extra math for file protocol to support ie based
absUrl = adjustFileProtocolUrl(newUrl.toString());
}
else {
URL newUrl = new URL(fBaseUrl, url);
absUrl = newUrl.toString();
}
}
catch (MalformedURLException me) {
}
// convert everything to forward slash
absUrl = PathHelper.switchToForwardSlashes(absUrl);
}
else {
// the given may be based on file
if (urlString != null) {
// swich the url to proper direction
url = PathHelper.removeLeadingSeparator(url);
File fle = new File(urlString, url);
absUrl = fle.getPath();
}
// convert everything to forward slash
absUrl = PathHelper.switchToForwardSlashes(absUrl);
// if the path ends with ".." we need to add a terminating slash
// or
// else the link will not be resolved correctly. (it will look
// like
// /url/path/to/somewhere/.. instead of /url/path/to/
if (absUrl.endsWith(FORWARD_SLASH + RELATIVE_PATH_SIG)) {
absUrl += FORWARD_SLASH;
}
}
// resolve relative path to absolute
absUrl = PathHelper.adjustPath(absUrl);
return absUrl;
}
private void initialize(String baseUrl, String docRoot) {
//
// Find out whether baes url is a url or file name
//
try {
String temp = PathHelper.appendTrailingURLSlash(baseUrl);
fBaseUrl = new URL(temp);
}
catch (MalformedURLException mue) {
}
if (fBaseUrl == null) {
// it is a file based url
fBaseUrlString = baseUrl;
}
// do the same for doc root
if (docRoot != null) {
try {
String temp = PathHelper.appendTrailingURLSlash(docRoot);
fDocRoot = new URL(temp);
}
catch (MalformedURLException mue) {
}
if (fDocRoot == null) {
// it is a file based url
fDocRootString = docRoot;
}
}
}
/**
* Convert the given url to a abolute url using the base url Input url can
* be of any othe following format Absolute urls -------------- .
* http://www.foo.com/ . http://www.foo.com . http://www.foo.com/folder .
* http://www.foo.com/folder/ . http://www.foo.com/index.html .
* http://www.foo.com/folder/index.html .
* http://www.foo.com/folder/../index.html Url relative on document root
* ------------------------- . / . /folder . /index.html .
* /folder/index.html . /folder/../index.html
*
* Self relative ------------------------- . index.html . ./index.html .
* ../index.html . folder/index.html . folder/../index.html
*
* file based url adds another dimension since it doesn't have a document
* root So uses fDocRoot if provided
*/
public String toAbsolute(String url) {
String absUrl = url;
URL newUrl = null;
// try to see it is a absolute url
try {
newUrl = new URL(url);
}
catch (MalformedURLException me) {
}
// if document root is provided
// do special case
if (newUrl == null) {
if (fDocRoot == null && fDocRootString == null) {
// try to check relative url
absUrl = convert(url, fBaseUrl, fBaseUrlString);
}
else {
// doc root is provided
// if the url is a doc root based use doc root
if (url.startsWith("/"))//$NON-NLS-1$
absUrl = convert(url, fDocRoot, fDocRootString);
else
absUrl = convert(url, fBaseUrl, fBaseUrlString);
}
}
return absUrl;
}
/**
* Convert from an absolute url to relative url based on the given url
* Both are assumed to be ablsute url
*/
public String toRelative(String url, String documentUrl) {
String output = url;
// assuming both urls are absolute
try {
URL inputUrl = new URL(url);
URL docUrl = new URL(documentUrl);
// filter out if the urls are not fro the same domain
if (!inputUrl.getProtocol().equals(docUrl.getProtocol()) || !inputUrl.getHost().equals(docUrl.getHost()) || inputUrl.getPort() != docUrl.getPort())
return output;
// both url are coming form the same place
// strip off the domain parts
String inputName = inputUrl.getFile();
String docName = docUrl.getFile();
output = PathHelper.convertToRelative(inputName, docName);
}
catch (MalformedURLException me) {
output = null;
}
return output;
}
}