michael@0: /* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: package org.mozilla.gecko.util;
michael@0: 
michael@0: import android.net.Uri;
michael@0: import android.text.TextUtils;
michael@0: 
michael@0: public class StringUtils {
michael@0: 
michael@0:     private static final String FILTER_URL_PREFIX = "filter://";
michael@0: 
michael@0:     /*
michael@0:      * This method tries to guess if the given string could be a search query or URL,
michael@0:      * and returns a previous result if there is ambiguity
michael@0:      *
michael@0:      * Search examples:
michael@0:      *  foo
michael@0:      *  foo bar.com
michael@0:      *  foo http://bar.com
michael@0:      *
michael@0:      * URL examples
michael@0:      *  foo.com
michael@0:      *  foo.c
michael@0:      *  :foo
michael@0:      *  http://foo.com bar
michael@0:      *
michael@0:      * wasSearchQuery specifies whether text was a search query before the latest change
michael@0:      * in text. In ambiguous cases where the new text can be either a search or a URL,
michael@0:      * wasSearchQuery is returned
michael@0:     */
michael@0:     public static boolean isSearchQuery(String text, boolean wasSearchQuery) {
michael@0:         // We remove leading and trailing white spaces when decoding URLs
michael@0:         text = text.trim();
michael@0:         if (text.length() == 0)
michael@0:             return wasSearchQuery;
michael@0: 
michael@0:         int colon = text.indexOf(':');
michael@0:         int dot = text.indexOf('.');
michael@0:         int space = text.indexOf(' ');
michael@0: 
michael@0:         // If a space is found before any dot and colon, we assume this is a search query
michael@0:         if (space > -1 && (colon == -1 || space < colon) && (dot == -1 || space < dot)) {
michael@0:             return true;
michael@0:         }
michael@0:         // Otherwise, if a dot or a colon is found, we assume this is a URL
michael@0:         if (dot > -1 || colon > -1) {
michael@0:             return false;
michael@0:         }
michael@0:         // Otherwise, text is ambiguous, and we keep its status unchanged
michael@0:         return wasSearchQuery;
michael@0:     }
michael@0: 
michael@0:     public static class UrlFlags {
michael@0:         public static final int NONE = 0;
michael@0:         public static final int STRIP_HTTPS = 1;
michael@0:     }
michael@0: 
michael@0:     public static String stripScheme(String url) {
michael@0:         return stripScheme(url, UrlFlags.NONE);
michael@0:     }
michael@0: 
michael@0:     public static String stripScheme(String url, int flags) {
michael@0:         if (url == null) {
michael@0:             return url;
michael@0:         }
michael@0: 
michael@0:         int start = 0;
michael@0:         int end = url.length();
michael@0: 
michael@0:         if (url.startsWith("http://")) {
michael@0:             start = 7;
michael@0:         } else if (url.startsWith("https://") && flags == UrlFlags.STRIP_HTTPS) {
michael@0:             start = 8;
michael@0:         }
michael@0: 
michael@0:         if (url.endsWith("/")) {
michael@0:             end--;
michael@0:         }
michael@0: 
michael@0:         return url.substring(start, end);
michael@0:     }
michael@0: 
michael@0:     public static String stripCommonSubdomains(String host) {
michael@0:         if (host == null) {
michael@0:             return host;
michael@0:         }
michael@0: 
michael@0:         // In contrast to desktop, we also strip mobile subdomains,
michael@0:         // since its unlikely users are intentionally typing them
michael@0:         int start = 0;
michael@0: 
michael@0:         if (host.startsWith("www.")) {
michael@0:             start = 4;
michael@0:         } else if (host.startsWith("mobile.")) {
michael@0:             start = 7;
michael@0:         } else if (host.startsWith("m.")) {
michael@0:             start = 2;
michael@0:         }
michael@0: 
michael@0:         return host.substring(start);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Searches the url query string for the first value with the given key.
michael@0:      */
michael@0:     public static String getQueryParameter(String url, String desiredKey) {
michael@0:         if (TextUtils.isEmpty(url) || TextUtils.isEmpty(desiredKey)) {
michael@0:             return null;
michael@0:         }
michael@0: 
michael@0:         final String[] urlParts = url.split("\\?");
michael@0:         if (urlParts.length < 2) {
michael@0:             return null;
michael@0:         }
michael@0: 
michael@0:         final String query = urlParts[1];
michael@0:         for (final String param : query.split("&")) {
michael@0:             final String pair[] = param.split("=");
michael@0:             final String key = Uri.decode(pair[0]);
michael@0: 
michael@0:             // Key is empty or does not match the key we're looking for, discard
michael@0:             if (TextUtils.isEmpty(key) || !key.equals(desiredKey)) {
michael@0:                 continue;
michael@0:             }
michael@0:             // No value associated with key, discard
michael@0:             if (pair.length < 2) {
michael@0:                 continue;
michael@0:             }
michael@0:             final String value = Uri.decode(pair[1]);
michael@0:             if (TextUtils.isEmpty(value)) {
michael@0:                 return null;
michael@0:             }
michael@0:             return value;
michael@0:         }
michael@0: 
michael@0:         return null;
michael@0:     }
michael@0: 
michael@0:     public static boolean isFilterUrl(String url) {
michael@0:         if (TextUtils.isEmpty(url)) {
michael@0:             return false;
michael@0:         }
michael@0: 
michael@0:         return url.startsWith(FILTER_URL_PREFIX);
michael@0:     }
michael@0: 
michael@0:     public static String getFilterFromUrl(String url) {
michael@0:         if (TextUtils.isEmpty(url)) {
michael@0:             return null;
michael@0:         }
michael@0: 
michael@0:         return url.substring(FILTER_URL_PREFIX.length());
michael@0:     }
michael@0: }