1/*
2 * Copyright (c) 2017, Daniel Gultsch All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without modification,
5 * are permitted provided that the following conditions are met:
6 *
7 * 1. Redistributions of source code must retain the above copyright notice, this
8 * list of conditions and the following disclaimer.
9 *
10 * 2. Redistributions in binary form must reproduce the above copyright notice,
11 * this list of conditions and the following disclaimer in the documentation and/or
12 * other materials provided with the distribution.
13 *
14 * 3. Neither the name of the copyright holder nor the names of its contributors
15 * may be used to endorse or promote products derived from this software without
16 * specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
22 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
25 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
27 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30package eu.siacs.conversations.utils;
31
32import com.google.common.base.Strings;
33
34import java.net.URI;
35import java.net.URISyntaxException;
36import java.util.regex.Pattern;
37
38import eu.siacs.conversations.entities.Conversational;
39import eu.siacs.conversations.entities.Message;
40import eu.siacs.conversations.http.AesGcmURL;
41import eu.siacs.conversations.http.URL;
42import eu.siacs.conversations.ui.util.QuoteHelper;
43
44public class MessageUtils {
45
46 private static final Pattern LTR_RTL = Pattern.compile("(\\u200E[^\\u200F]*\\u200F){3,}");
47
48 public static final String EMPTY_STRING = "";
49
50 public static String prepareQuote(Message message) {
51 final StringBuilder builder = new StringBuilder();
52 final String body;
53 if (message.hasMeCommand()) {
54 final String nick;
55 if (message.getStatus() == Message.STATUS_RECEIVED) {
56 if (message.getConversation().getMode() == Conversational.MODE_MULTI) {
57 nick = Strings.nullToEmpty(message.getCounterpart().getResource());
58 } else {
59 nick = message.getContact().getPublicDisplayName();
60 }
61 } else {
62 nick = UIHelper.getMessageDisplayName(message);
63 }
64 body = nick + " " + message.getQuoteableBody().substring(Message.ME_COMMAND.length());
65 } else {
66 body = message.getQuoteableBody();
67 }
68 for (String line : body.split("\n")) {
69 if (!(line.length() <= 0) && QuoteHelper.isNestedTooDeeply(line)) {
70 continue;
71 }
72 if (builder.length() != 0) {
73 builder.append('\n');
74 }
75 builder.append(line.trim());
76 }
77 return builder.toString();
78 }
79
80 public static boolean treatAsDownloadable(final String body, final boolean oob, final boolean legacyEncryption) {
81 if (oob) return true;
82
83 final String[] lines = body.split("\n");
84 if (lines.length == 0) {
85 return false;
86 }
87 for (final String line : lines) {
88 if (line.contains("\\s+")) {
89 return false;
90 }
91 }
92 final URI uri;
93 try {
94 uri = new URI(lines[0]);
95 } catch (final URISyntaxException e) {
96 return false;
97 }
98 if (!URL.WELL_KNOWN_SCHEMES.contains(uri.getScheme())) {
99 return false;
100 }
101 final String ref = uri.getFragment();
102 final String protocol = uri.getScheme();
103 final boolean encrypted = ref != null && AesGcmURL.IV_KEY.matcher(ref).matches();
104 final boolean followedByDataUri = lines.length == 2 && lines[1].startsWith("data:");
105 final boolean validAesGcm = AesGcmURL.PROTOCOL_NAME.equalsIgnoreCase(protocol) && encrypted && (lines.length == 1 || followedByDataUri);
106 final boolean validProtocol = "http".equalsIgnoreCase(protocol) || "https".equalsIgnoreCase(protocol);
107 final boolean validOob = validProtocol && (oob || encrypted || (legacyEncryption && uri.getPath() != null && (uri.getPath().endsWith(".xdc") || uri.getPath().endsWith(".webp") || uri.getPath().endsWith(".gif") || uri.getPath().endsWith(".png")))) && lines.length == 1;
108 return validAesGcm || validOob;
109 }
110
111 public static String aesgcmDownloadable(final String body) {
112 final String[] lines = body.split("\n");
113 if (lines.length == 0) {
114 return null;
115 }
116 for (final String line : lines) {
117 if (line.contains("\\s+")) {
118 return null;
119 }
120 }
121 final URI uri;
122 try {
123 uri = new URI(lines[0]);
124 } catch (final URISyntaxException e) {
125 return null;
126 }
127 if (!URL.WELL_KNOWN_SCHEMES.contains(uri.getScheme())) {
128 return null;
129 }
130 final String ref = uri.getFragment();
131 final String protocol = uri.getScheme();
132 final boolean encrypted = ref != null && AesGcmURL.IV_KEY.matcher(ref).matches();
133 final boolean followedByDataUri = lines.length == 2 && lines[1].startsWith("data:");
134 final boolean validAesGcm = AesGcmURL.PROTOCOL_NAME.equalsIgnoreCase(protocol) && encrypted && (lines.length == 1 || followedByDataUri);
135 return validAesGcm ? lines[0] : null;
136 }
137
138 public static String filterLtrRtl(String body) {
139 return LTR_RTL.matcher(body).replaceFirst(EMPTY_STRING);
140 }
141
142 public static boolean unInitiatedButKnownSize(Message message) {
143 return message.getType() == Message.TYPE_TEXT && message.getTransferable() == null && message.isOOb() && message.getFileParams().url != null &&
144 (message.getFileParams().size != null || (message.getOob() != null && message.getOob().getScheme() != null && message.getOob().getScheme().equalsIgnoreCase("cid")));
145 }
146}