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;
 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    private 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.getBody().substring(Message.ME_COMMAND.length());
 65        } else {
 66            body = message.getMergedBody().toString();
 67        }
 68        for (String line : body.split("\n")) {
 69            if (line.length() <= 0) {
 70                continue;
 71            }
 72            final char c = line.charAt(0);
 73            if (QuoteHelper.isNestedTooDeeply(line)) {
 74                continue;
 75            }
 76            if (builder.length() != 0) {
 77                builder.append('\n');
 78            }
 79            builder.append(line.trim());
 80        }
 81        return builder.toString();
 82    }
 83
 84    public static boolean treatAsDownloadable(final String body, final boolean oob) {
 85        if (oob) return true;
 86
 87        final String[] lines = body.split("\n");
 88        if (lines.length == 0) {
 89            return false;
 90        }
 91        for (final String line : lines) {
 92            if (line.contains("\\s+")) {
 93                return false;
 94            }
 95        }
 96        final URI uri;
 97        try {
 98            uri = new URI(lines[0]);
 99        } catch (final URISyntaxException e) {
100            return false;
101        }
102        if (!URL.WELL_KNOWN_SCHEMES.contains(uri.getScheme())) {
103            return false;
104        }
105        final String ref = uri.getFragment();
106        final String protocol = uri.getScheme();
107        final boolean encrypted = ref != null && AesGcmURL.IV_KEY.matcher(ref).matches();
108        final boolean followedByDataUri = lines.length == 2 && lines[1].startsWith("data:");
109        final boolean validAesGcm = AesGcmURL.PROTOCOL_NAME.equalsIgnoreCase(protocol) && encrypted && (lines.length == 1 || followedByDataUri);
110        final boolean validProtocol = "http".equalsIgnoreCase(protocol) || "https".equalsIgnoreCase(protocol);
111        final boolean validOob = validProtocol && (oob || encrypted) && lines.length == 1;
112        return validAesGcm || validOob;
113    }
114
115    public static String filterLtrRtl(String body) {
116        return LTR_RTL.matcher(body).replaceFirst(EMPTY_STRING);
117    }
118
119    public static boolean unInitiatedButKnownSize(Message message) {
120        return message.getType() == Message.TYPE_TEXT && message.getTransferable() == null && message.isOOb() && message.getFileParams().url != null &&
121               (message.getFileParams().size != null || (message.getOob() != null && message.getOob().getScheme().equalsIgnoreCase("cid")));
122    }
123}