PostUtils.java

/*
 * Copyright (C) 2019 SOBotics (https://sobotics.org) and contributors on GitHub
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>
 */

package org.sobotics.guttenberg.utils;

import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.sobotics.chatexchange.chat.Message;
import org.sobotics.chatexchange.chat.Room;
import org.sobotics.chatexchange.chat.event.PingMessageEvent;
import org.sobotics.guttenberg.clients.Guttenberg;
import org.sobotics.guttenberg.entities.Post;
import org.sobotics.guttenberg.entities.PostMatch;
import org.sobotics.guttenberg.entities.SOUser;

import java.io.IOException;
import java.time.Instant;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class PostUtils {

  private static final Logger LOGGER = LoggerFactory.getLogger(PostUtils.class);


  private PostUtils() {
  }


  public static Post getPost(JsonObject answer) {

    Post np = new Post();

    JsonObject answererJSON = answer.get("owner").getAsJsonObject();

    np.setAnswerCreationDate(Instant.ofEpochSecond(answer.get("creation_date").getAsInt()));
    np.setAnswerID(answer.get("answer_id").getAsInt());
    np.setQuestionID(answer.get("question_id").getAsInt());
    np.setBody(answer.get("body").getAsString());
    np.setBodyMarkdown(JsonUtils.escapeHtmlEncoding(answer.get("body_markdown").getAsString()));
    np.setUnescapedBodyMarkdown(answer.get("body_markdown").getAsString());

    JsonArray jsonTags = new JsonArray();

    try {
      jsonTags = answer.get("tags").getAsJsonArray();

      List<String> tags = new ArrayList<String>();

      for (JsonElement tag : jsonTags) {
        tags.add(tag.getAsString());
      }

      np.setTags(tags);
    } catch (Throwable e) {
      //disabled, since our requests are causing a bug: https://stackapps.com/q/7213/43403
      //LOGGER.warn("No tags found", e);
    }

    SOUser answerer = new SOUser();

    try {
      answerer.setReputation(answererJSON.get("reputation").getAsLong());
      answerer.setUsername(JsonUtils.escapeHtmlEncoding(answererJSON.get("display_name").getAsString()));
      answerer.setUserType(answererJSON.get("user_type").getAsString());
      answerer.setUserId(answererJSON.get("user_id").getAsInt());
    } catch (NullPointerException e) {
      LOGGER.debug("Could not load user", e);
    }

    np.setAnswerer(answerer);

    return np;

  }


  /**
   * Splits a post into code, plaintext and quotes
   *
   * @author ArtOfCode
   */
  public static JsonObject separateBodyParts(Post post) {
    JsonObject result = new JsonObject();
    String markdown = post.getBodyMarkdown();
    String[] paragraphs = markdown.split("\\n{2,}");

    StringBuilder plain = new StringBuilder();
    StringBuilder code = new StringBuilder();
    StringBuilder quote = new StringBuilder();
    for (String paragraph : paragraphs) {
      if (paragraph.trim().charAt(0) == '>') {
        quote.append(paragraph).append("\n");
      } else if (paragraph.startsWith("    ")) {
        code.append(paragraph).append("\n");
      } else {
        plain.append(paragraph).append("\n");
      }
    }

    result.addProperty("body_plain", plain.toString());
    result.addProperty("body_code", code.toString());
    result.addProperty("body_quote", quote.toString());

    return result;
  }


  public static List<String> getCodeParagraphs(String markdown) {
    List<String> output = new ArrayList<String>();

    String[] paragraphs = markdown.split("\\n");
    StringBuilder buffer = new StringBuilder();

    for (String paragraph : paragraphs) {
      if (paragraph.startsWith("    ")) {
        // found a codeblock -> add to buffer
        buffer.append(paragraph).append("\n");
      } else {
        // a non-code paragraph. This resets the codeblock
        // -> write buffer to array; then clear buffer
        if (buffer.length() > 4) {
          output.add(buffer.toString());
        }
        buffer = new StringBuilder();
      }
    }

    return output;
  }


  public static void reply(Room room, PingMessageEvent event, boolean isReply) {
    Message message = event.getMessage();
    Message parentMessage = room.getMessage(event.getParentMessageId());
    long parentMessageId = parentMessage.getId();
    LOGGER.debug("Received reply: " + message.getContent());

    if (CheckUtils.checkIfUserIsBlacklisted(event.getUserId(), room.getHost().getBaseUrl())) {
      LOGGER.info("Blacklisted user " + event.getUserName() + " replied to the bot.");
      return;
    }

    PostUtils.checkPingForFeedback(room, event);

    // check if message is a report before editing it
    boolean isReport = true;
    if (!parentMessage.getPlainContent().startsWith("[ [")) {
      if (parentMessage.getPlainContent().startsWith("---")) {
        LOGGER.debug("This post has already been handled");
        return;
      }

      isReport = false;
    }

    String newMessage = "";
    boolean isValidFeedback = false;
    if (CommandUtils.checkForCommand(message.getContent(), "k")) {
      newMessage = "---" + parentMessage.getPlainContent() + "--- k by " + message.getUser().getName();
      isValidFeedback = true;
    }
    if (CommandUtils.checkForCommand(message.getContent(), "f")) {
      newMessage = "---" + parentMessage.getPlainContent() + "--- f by " + message.getUser().getName();
      isValidFeedback = true;
    }

    if (!isReport && isValidFeedback) {
      room.replyTo(message.getId(), "You can only send feedback to reports. This message wasn't one.");
      return;
    }

    // if newMessage longer than 10, edit it
    if (newMessage.length() > 10) {
      try {
        room.edit(parentMessageId, newMessage);
      } catch (Throwable e) {
        LOGGER.info("Could not edit message", e);
      }
    }
  }


  public static Integer getIdFromLink(String link) {
    if (link == null) {
      return null;
    }

    if (link.contains("/")) {
      String[] parts = link.split("/");
      for (String s : parts) {
        if (s.matches("\\d+")) {
          try {
            return Integer.parseInt(s);
          } catch (NumberFormatException e) {
            // Do nothing not a number
          }
        }
      }
    }

    String suid = link.replaceAll("[^\\d.]", "");
    try {
      return Integer.parseInt(suid);
    } catch (NumberFormatException e) {
      LOGGER.error(suid + " can't be parsed", e);
      return null;
    }

  }


  public static String storeReport(PostMatch match) throws IOException {
    LOGGER.debug("Sending match to CopyPastor...");
    Properties prop = Guttenberg.getLoginProperties();

    String targetUsername = "";
    String targetUserLink = "";
    String originalUsername = "";
    String originalUserLink = "";

    Post target = match.getTarget();
    Post original = match.getOriginal();


    if (target.getAnswerer() != null) {
      targetUsername = target.getAnswerer().getUsername();
      targetUserLink = "https://stackoverflow.com/users/" + target.getAnswerer().getUserId() + "/";
    }

    if (original.getAnswerer() != null) {
      originalUsername = original.getAnswerer().getUsername();
      originalUserLink = "https://stackoverflow.com/users/" + original.getAnswerer().getUserId() + "/";
    }

    String url = prop.getProperty("copypastor_url", "http://localhost:5000") + "/posts/create";

    LOGGER.debug("Sending data to CopyPastor");
    LOGGER.debug("CopyPastorURL: " + url);
    LOGGER.debug("Score: " + match.getTotalScore());
    LOGGER.debug("Reasons: " + match.getCopyPastorReasonString());

    JsonObject output = JsonUtils.post(url,
      "key", prop.getProperty("copypastor_key", "no_key"),
      "url_one", "//stackoverflow.com/a/" + target.getAnswerID(),
      "url_two", "//stackoverflow.com/a/" + original.getAnswerID(),
      "title_one", "Possible Plagiarism",
      "title_two", "Original Post",
      "date_one", "" + target.getAnswerCreationDate().getEpochSecond(),
      "date_two", "" + original.getAnswerCreationDate().getEpochSecond(),
      "body_one", target.getUnescapedBodyMarkdown(),
      "body_two", original.getUnescapedBodyMarkdown(),
      "username_one", targetUsername,
      "username_two", originalUsername,
      "user_url_one", targetUserLink,
      "user_url_two", originalUserLink,
      "score", "" + match.getTotalScore(),
      "reasons", match.getCopyPastorReasonString());

    LOGGER.debug("Data sent to CopyPastor");

    return prop.getProperty("copypastor_url", "http://localhost:5000") + "/posts/" + output.get("post_id").getAsString();
  }


  @Deprecated
  public static String storeReport(Post target, Post original) throws IOException {
    Properties prop = Guttenberg.getLoginProperties();

    String targetUsername = "";
    String targetUserLink = "";
    String originalUsername = "";
    String originalUserLink = "";

    if (target.getAnswerer() != null) {
      targetUsername = target.getAnswerer().getUsername();
      targetUserLink = "https://stackoverflow.com/users/" + target.getAnswerer().getUserId() + "/";
    }

    if (original.getAnswerer() != null) {
      originalUsername = original.getAnswerer().getUsername();
      originalUserLink = "https://stackoverflow.com/users/" + original.getAnswerer().getUserId() + "/";
    }

    String url = prop.getProperty("copypastor_url", "http://localhost:5000") + "/posts/create";
    JsonObject output = JsonUtils.post(url,
      "key", prop.getProperty("copypastor_key", "no_key"),
      "url_one", "//stackoverflow.com/a/" + target.getAnswerID(),
      "url_two", "//stackoverflow.com/a/" + original.getAnswerID(),
      "title_one", "Possible Plagiarism",
      "title_two", "Original Post",
      "date_one", "" + target.getAnswerCreationDate().getEpochSecond(),
      "date_two", "" + original.getAnswerCreationDate().getEpochSecond(),
      "body_one", target.getUnescapedBodyMarkdown(),
      "body_two", original.getUnescapedBodyMarkdown(),
      "username_one", targetUsername,
      "username_two", originalUsername,
      "user_url_one", targetUserLink,
      "user_url_two", originalUserLink);

    return prop.getProperty("copypastor_url", "http://localhost:5000") + "/posts/" + output.get("post_id").getAsString();
  }


  /**
   * Sends the feedback to CopyPastor
   */
  public static void checkPingForFeedback(Room room, PingMessageEvent ping) {
    LOGGER.debug("Checking message for feedback");
    int reportId = -1;
    Message reportMsg = null;
    Message pingMsg = ping.getMessage();
    long parentMsg = ping.getParentMessageId();

    if (parentMsg == -1) {
      //this wasn't a reply
      return;
    }

    reportMsg = room.getMessage(parentMsg);

    reportId = PostUtils.getReportIdFromChatMessage(reportMsg);
    LOGGER.trace("ReportId in message: " + reportId);

    if (reportId == -1)
      return;


    try {
      if (CommandUtils.checkForCommand(pingMsg.getContent(), "k") || CommandUtils.checkForCommand(pingMsg.getContent(), "tp")) {
        PostUtils.storeFeedback(room, ping, reportId, "tp");
      }
      if (CommandUtils.checkForCommand(pingMsg.getContent(), "f") || CommandUtils.checkForCommand(pingMsg.getContent(), "fp")) {
        PostUtils.storeFeedback(room, ping, reportId, "fp");
      }
    } catch (IOException e) {
      LOGGER.error("Could not save feedback!", e);
    } // try-catch
  } // checkPingForFeedback


  /**
   * Returns the CopyPastor report ID
   * -1, if the message wasn't a report
   */
  public static int getReportIdFromChatMessage(Message message) {
    Properties prop = Guttenberg.getLoginProperties();
    boolean isMyMessage = message.getUser().getName().equalsIgnoreCase(prop.getProperty("username", "Guttenberg"));
    String plain = message.getPlainContent();

    try {
      Pattern pattern = Pattern.compile("\\[ \\[Guttenberg\\].*\\[CopyPastor]\\(.*\\/posts\\/(?<reportId>\\d*)\\)");
      Matcher matcher = pattern.matcher(plain);

      if (isMyMessage && matcher.find()) {
        String reportId = matcher.group("reportId");
        try {
          return Integer.parseInt(reportId);
        } catch (NumberFormatException e) {
          LOGGER.warn(e.getMessage());
          return -1;
        } // try-catch
      } else {
        return -1;
      } // else-if
    } catch (Exception e) {
      LOGGER.error("FATAL ERROR! RegEx-Pattern might be broken!", e);
      return -1;
    } // try-catch
  } // getReportIdFromChatMessage


  /**
   * Sends the feedback to CopyPastor
   *
   * @param ping     The PingMessageEvent that contains the feedback
   * @param reportId The ID of the CopyPastor-Report
   * @param feedback tp or fp
   */
  public static void storeFeedback(Room room, PingMessageEvent ping, int reportId, String feedback) throws IOException {
    LOGGER.debug("Sending feedback " + feedback + " for report " + reportId);
    Properties prop = Guttenberg.getLoginProperties();

    String url = prop.getProperty("copypastor_url", "http://localhost:5000") + "/feedback/create";
    JsonObject output = JsonUtils.post(url,
      "key", prop.getProperty("copypastor_key", "no_key"),
      "post_id", "" + reportId,
      "feedback_type", feedback,
      "username", ping.getUserName(),
      "link", ping.getMessage().getUser().getProfileLink()
    );

    LOGGER.trace("Response form CopyPastor:\n" + output);

    String status = output.get("status").getAsString();
    if (!status.equalsIgnoreCase("success")) {
      String statusMsg = output.get("message").getAsString();
      if (ping.getMessage().getUser().isRoomOwner()) {
        ping.getRoom().replyTo(ping.getMessage().getId(), statusMsg);
      } else {
        ping.getRoom().replyTo(ping.getMessage().getId(), "Your feedback could not be saved.");
      }

      LOGGER.error(statusMsg);
    } // if
  } // storeFeedback
} // class