/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.android.browser;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class UrlUtils {

    // Regular expression which matches http://, followed by some stuff, followed by
    // optionally a trailing slash, all matched as separate groups.
    private static final Pattern STRIP_URL_PATTERN = Pattern.compile("^(http://)(.*?)(/$)?");

    private UrlUtils() { /* cannot be instantiated */ }

    /**
     * Strips the provided url of preceding "http://" and any trailing "/". Does not
     * strip "https://". If the provided string cannot be stripped, the original string
     * is returned.
     *
     * TODO: Put this in TextUtils to be used by other packages doing something similar.
     *
     * @param url a url to strip, like "http://www.google.com/"
     * @return a stripped url like "www.google.com", or the original string if it could
     *         not be stripped
     */
    /* package */ static String stripUrl(String url) {
        if (url == null) return null;
        Matcher m = STRIP_URL_PATTERN.matcher(url);
        if (m.matches() && m.groupCount() == 3) {
            return m.group(2);
        } else {
            return url;
        }
    }
}