MessageUtils.java

  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;
 33import eu.siacs.conversations.entities.Conversational;
 34import eu.siacs.conversations.entities.Message;
 35import eu.siacs.conversations.http.AesGcmURL;
 36import eu.siacs.conversations.http.URL;
 37import eu.siacs.conversations.ui.util.QuoteHelper;
 38import java.net.URI;
 39import java.net.URISyntaxException;
 40import java.util.regex.Pattern;
 41
 42public class MessageUtils {
 43
 44    private static final Pattern LTR_RTL = Pattern.compile("(\\u200E[^\\u200F]*\\u200F){3,}");
 45
 46    public static final String EMPTY_STRING = "";
 47
 48    public static String prepareQuote(final Message message) {
 49        final StringBuilder builder = new StringBuilder();
 50        final String body;
 51        if (message.hasMeCommand()) {
 52            final String nick;
 53            if (message.getStatus() == Message.STATUS_RECEIVED) {
 54                if (message.getConversation().getMode() == Conversational.MODE_MULTI) {
 55                    nick = Strings.nullToEmpty(message.getCounterpart().getResource());
 56                } else {
 57                    nick = message.getContact().getPublicDisplayName();
 58                }
 59            } else {
 60                nick = UIHelper.getMessageDisplayName(message);
 61            }
 62            body = nick + " " + message.getBody().substring(Message.ME_COMMAND.length());
 63        } else {
 64            body = message.getBody();
 65        }
 66        for (String line : body.split("\n")) {
 67            if (!(line.length() <= 0) && QuoteHelper.isNestedTooDeeply(line)) {
 68                continue;
 69            }
 70            if (builder.length() != 0) {
 71                builder.append('\n');
 72            }
 73            builder.append(line.trim());
 74        }
 75        return builder.toString();
 76    }
 77
 78    public static boolean treatAsDownloadable(final String body, final boolean oob) {
 79        final String[] lines = body.split("\n");
 80        if (lines.length == 0) {
 81            return false;
 82        }
 83        for (final String line : lines) {
 84            if (line.contains("\\s+")) {
 85                return false;
 86            }
 87        }
 88        final URI uri;
 89        try {
 90            uri = new URI(lines[0]);
 91        } catch (final URISyntaxException e) {
 92            return false;
 93        }
 94        if (!URL.WELL_KNOWN_SCHEMES.contains(uri.getScheme())) {
 95            return false;
 96        }
 97        final String ref = uri.getFragment();
 98        final String protocol = uri.getScheme();
 99        final boolean encrypted = ref != null && AesGcmURL.IV_KEY.matcher(ref).matches();
100        final boolean followedByDataUri = lines.length == 2 && lines[1].startsWith("data:");
101        final boolean validAesGcm =
102                AesGcmURL.PROTOCOL_NAME.equalsIgnoreCase(protocol)
103                        && encrypted
104                        && (lines.length == 1 || followedByDataUri);
105        final boolean validProtocol =
106                "http".equalsIgnoreCase(protocol) || "https".equalsIgnoreCase(protocol);
107        final boolean validOob = validProtocol && (oob || encrypted) && lines.length == 1;
108        return validAesGcm || validOob;
109    }
110
111    public static String filterLtrRtl(String body) {
112        return LTR_RTL.matcher(body).replaceFirst(EMPTY_STRING);
113    }
114
115    public static boolean unInitiatedButKnownSize(Message message) {
116        return message.getType() == Message.TYPE_TEXT
117                && message.getTransferable() == null
118                && message.isOOb()
119                && message.getFileParams().size != null
120                && message.getFileParams().url != null;
121    }
122}