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.MalformedURLException;
 35import java.net.URL;
 36import java.util.regex.Pattern;
 37
 38import eu.siacs.conversations.entities.Conversational;
 39import eu.siacs.conversations.entities.Message;
 40import eu.siacs.conversations.http.AesGcmURLStreamHandler;
 41import eu.siacs.conversations.http.P1S3UrlStreamHandler;
 42
 43public class MessageUtils {
 44
 45	private static final Pattern LTR_RTL = Pattern.compile("(\\u200E[^\\u200F]*\\u200F){3,}");
 46
 47	private static final String EMPTY_STRING = "";
 48
 49	public static String prepareQuote(Message message) {
 50		final StringBuilder builder = new StringBuilder();
 51		final String body;
 52		if (message.hasMeCommand()) {
 53			final String nick;
 54			if (message.getStatus() == Message.STATUS_RECEIVED) {
 55				if (message.getConversation().getMode() == Conversational.MODE_MULTI) {
 56					nick = Strings.nullToEmpty(message.getCounterpart().getResource());
 57				} else {
 58					nick = message.getContact().getPublicDisplayName();
 59				}
 60			} else {
 61				nick =  UIHelper.getMessageDisplayName(message);
 62			}
 63			body = nick + " " + message.getBody().substring(Message.ME_COMMAND.length());
 64		} else {
 65			body = message.getMergedBody().toString();
 66        }
 67		for (String line : body.split("\n")) {
 68			if (line.length() <= 0) {
 69				continue;
 70			}
 71			final char c = line.charAt(0);
 72			if (c == '>' && UIHelper.isPositionFollowedByQuoteableCharacter(line, 0)
 73					|| (c == '\u00bb' && !UIHelper.isPositionFollowedByQuote(line, 0))) {
 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		try {
 86			final String[] lines = body.split("\n");
 87			if (lines.length == 0) {
 88				return false;
 89			}
 90			for (String line : lines) {
 91				if (line.contains("\\s+")) {
 92					return false;
 93				}
 94			}
 95			final URL url = new URL(lines[0]);
 96			final String ref = url.getRef();
 97			final String protocol = url.getProtocol();
 98			final boolean encrypted = ref != null && AesGcmURLStreamHandler.IV_KEY.matcher(ref).matches();
 99			final boolean followedByDataUri = lines.length == 2 && lines[1].startsWith("data:");
100			final boolean validAesGcm = AesGcmURLStreamHandler.PROTOCOL_NAME.equalsIgnoreCase(protocol) && encrypted && (lines.length == 1 || followedByDataUri);
101			final boolean validProtocol = "http".equalsIgnoreCase(protocol) || "https".equalsIgnoreCase(protocol) || P1S3UrlStreamHandler.PROTOCOL_NAME.equalsIgnoreCase(protocol);
102			final boolean validOob = validProtocol && (oob || encrypted) && lines.length == 1;
103			return validAesGcm || validOob;
104		} catch (MalformedURLException e) {
105			return false;
106		}
107	}
108
109	public static String filterLtrRtl(String body) {
110		return LTR_RTL.matcher(body).replaceFirst(EMPTY_STRING);
111	}
112
113	public static boolean unInitiatedButKnownSize(Message message) {
114		return message.getType() == Message.TYPE_TEXT && message.getTransferable() == null && message.isOOb() && message.getFileParams().size > 0 && message.getFileParams().url != null;
115	}
116}