[module-utilities] Rewrite ChatbotCommand.java

2 files changed, 147 insertions, 40 deletions

diff --git a/module-utilities/pom.xml b/module-utilities/pom.xml
index 5cc5cae..615ed08 100644
--- a/module-utilities/pom.xml
+++ b/module-utilities/pom.xml
@@ -31,7 +31,6 @@
         </scm>
 
         <dependencies>
-
                 <!-- Cross-module -->
                 <dependency>
                         <groupId>zajc.libot</groupId>
@@ -42,11 +41,10 @@
                         <artifactId>module-libot</artifactId>
                 </dependency>
 
-                <!-- Chatbot support -->
+                <!-- HTTP -->
                 <dependency>
-                        <groupId>ca.pjer</groupId>
-                        <artifactId>chatter-bot-api</artifactId>
-                        <version>2.0.1</version>
+                        <groupId>com.konghq</groupId>
+                        <artifactId>unirest-java</artifactId>
                 </dependency>
                 
                 <!-- Annotations -->
@@ -54,7 +52,13 @@
                         <groupId>com.github.spotbugs</groupId>
                         <artifactId>spotbugs-annotations</artifactId>
                 </dependency>
-
+                
+                <!-- Compression -->
+                <dependency>
+                        <groupId>org.apache.commons</groupId>
+                        <artifactId>commons-compress</artifactId>
+                        <version>1.23.0</version>
+                </dependency>
         </dependencies>
 
         <build>
diff --git a/module-utilities/src/main/java/libot/commands/ChatbotCommand.java b/module-utilities/src/main/java/libot/commands/ChatbotCommand.java
index e036ba9..3bd223e 100644
--- a/module-utilities/src/main/java/libot/commands/ChatbotCommand.java
+++ b/module-utilities/src/main/java/libot/commands/ChatbotCommand.java
@@ -1,69 +1,172 @@
 package libot.commands;
 
-import static com.google.code.chatterbotapi.ChatterBotType.PANDORABOTS;
+import static com.github.markozajc.ef.EHandle.handle;
 import static java.util.regex.Pattern.compile;
+import static javax.xml.xpath.XPathConstants.STRING;
 import static libot.core.Constants.*;
 import static libot.core.commands.CommandCategory.UTILITIES;
 import static libot.utils.Utilities.array;
-import static org.slf4j.LoggerFactory.getLogger;
+import static org.apache.commons.lang3.tuple.Pair.of;
 
-import java.util.regex.Pattern;
+import java.io.*;
+import java.util.*;
+import java.util.concurrent.Callable;
+import java.util.regex.*;
 
-import org.slf4j.Logger;
+import javax.annotation.*;
+import javax.xml.parsers.*;
+import javax.xml.xpath.*;
 
-import com.google.code.chatterbotapi.*;
+import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.lang3.tuple.Pair;
+import org.xml.sax.SAXException;
 
+import kong.unirest.Unirest;
 import libot.core.commands.*;
 import libot.core.entities.CommandContext;
 
+@SuppressWarnings("java:S4248") // false positive spam (non-static pattern)
 public class ChatbotCommand extends Command {
 
-        private static final String CHOMSKY_ID = "b0dafd24ee35a477";
-        private static final Pattern XML_REGEX = compile("<(.*?)((?= \\/>)|>)");
-        private static final Logger LOG = getLogger(ChatbotCommand.class);
-        private static final ChatterBot CHATTER_BOT;
+        private static final String PANDORABOTS_EMOJI = "<:pandorabots:1129815071556653067>";
+        // nbsp used in place of spaces on the following line because ecj doesn't like
+        // codepoints in multiline strings
+        // https://github.com/eclipse-jdt/eclipse.jdt.core/issues/1237
+        private static final String NAME = "**Chomsky [Chatbot %s]**".formatted(PANDORABOTS_EMOJI); // NOSONAR it stays
+        private static final String BOT_ID = "b0dafd24ee35a477";
+
+        private static final String LEARN_TEXT = "Would you like to teach me a new question and answer?";
+        private static final String LEARN_RESPONSE = "I'm sorry, but learning is disabled in this session";
+        private static final String LEARN_SUGGESTION = "If you would like to teach me a better reply, just say \"Learn\".";
+
+        private static final DocumentBuilder DOCUMENT_BUILDER; // implementation isn't thread safe
+        private static final XPathExpression XPATH_EXTRACTOR; // explicitly not thread safe
+
+        private static final List<Pair<Pattern, String>> RESPONSE_PARSERS_RECURSIVE = new ArrayList<>();
+        private static final List<Pair<Pattern, String>> RESPONSE_PARSERS = new ArrayList<>();
 
         static {
-                ChatterBot chatterBot;
-                try {
-                        chatterBot = new ChatterBotFactory().create(PANDORABOTS, CHOMSKY_ID);
-                } catch (Exception e) {
-                        chatterBot = null;
-                        LOG.error("Failed to load the chatbot", e);
-                }
+                var dbf = DocumentBuilderFactory.newInstance();
+                DOCUMENT_BUILDER = handle((Callable<DocumentBuilder>) dbf::newDocumentBuilder, e -> null).get();
+
+                var xp = XPathFactory.newInstance().newXPath();
+                XPATH_EXTRACTOR = handle((Callable<XPathExpression>) () -> xp.compile("//result/that/text()"), e -> null).get();
+
+                // useless data, inner data discarded
+                RESPONSE_PARSERS.add(of(compile("(?s)<object[^>]*>.*?</object>"), "")); // NOSONAR
+                RESPONSE_PARSERS.add(of(compile("(?s)<param[^>]*>.*?</param>"), ""));
+                RESPONSE_PARSERS.add(of(compile("(?s)<embed[^>]*>.*?</embed>"), ""));
+                RESPONSE_PARSERS.add(of(compile("(?s)<script[^>]*>.*?</script>"), ""));
+                RESPONSE_PARSERS.add(of(compile("(?s)<style[^>]*>.*?</style>"), ""));
+
+                // useless tags, inner data kept
+                RESPONSE_PARSERS_RECURSIVE.add(of(compile("(?s)<font[^>]*>(.*?)</font>"), "$1"));
+                RESPONSE_PARSERS_RECURSIVE.add(of(compile("(?s)<div[^>]*>(.*?)</div>"), "$1\n"));
+
+                // html we can't turn into markdown but we still change
+                RESPONSE_PARSERS.add(of(compile("<a href=\"([^\"]*)\"[^>]*>(.*?)<\\/a>"), "$2 (<$1>)"));
+                RESPONSE_PARSERS.add(of(compile("<br> *"), "\n"));
+
+                // html we can turn into markdown
+                RESPONSE_PARSERS_RECURSIVE.add(of(compile("<b>(.*?)</b>"), "**$1**"));
+                RESPONSE_PARSERS_RECURSIVE.add(of(compile("<i>(.*?)</i>"), "*$1*"));
+                RESPONSE_PARSERS_RECURSIVE.add(of(compile("<u>(.*?)</u>"), "__$1__"));
 
-                CHATTER_BOT = chatterBot;
+                // botched punctuation
+                RESPONSE_PARSERS.add(of(compile(" {2,}"), " "));
+                RESPONSE_PARSERS.add(of(compile(" +(?=[\\.,!?])"), ""));
+
+                // STATIC_RESPONSES.put(q -> q.startsWith("web search"), )
         }
 
         @Override
-        @SuppressWarnings("null")
         public void execute(CommandContext c) throws Exception {
-                if (CHATTER_BOT == null)
-                        throw c.error("This feature is currently not available. Please try again later!", DISABLED);
+                var session = generateSession();
 
-                var session = CHATTER_BOT.createSession();
-
-                c.reply("You're connected!", """
-                        You can now start chatting with Chomsky. Say hi!
-                        Also, if you want Chomsky to ignore a message, prefix it with `>` (eg. `> this message is \
-                        ignored`).""", "Type in EXIT to quit", SUCCESS);
+                c.replyf("You're connected!", """
+                        You can now start chatting with %s. Say hi!
+                        Also, if you want Chomsky to ignore a message, prefix it with `#` (eg. `# this message is \
+                        ignored`).""", "Type in EXIT to quit", SUCCESS, NAME);
 
                 while (true) {
                         var m = c.askraw();
                         if ("exit".equalsIgnoreCase(m.getContentStripped())) {
                                 m.addReaction(ACCEPT_EMOJI).queue();
                                 break;
-                        }
 
-                        if (!m.getContentRaw().startsWith(">")) {
-                                String reply = session.think(m.getContentStripped());
-                                if (reply.length() == 0)
-                                        c.reply("...");
-                                else
-                                        c.reply(XML_REGEX.matcher(reply).replaceAll(""));
+                        } else if (!m.getContentRaw().startsWith("#")) {
+                                c.replyf("%s: %s", NAME, think(session, m.getContentStripped()));
                         }
                 }
+        }
+
+        @Nonnull
+        @SuppressWarnings("null")
+        private static String generateSession() {
+                return UUID.randomUUID().toString();
+        }
+
+        @Nonnull
+        public static String think(@Nonnull String text, @Nonnull String session) throws XPathExpressionException,
+                                                                                                                                                          SAXException, IOException {
+                if (text.equals("learn") || text.startsWith("learn ")) // return the replacement response
+                        return LEARN_RESPONSE;
+
+                var response = getResponse(text, session);
+                if (response == null) {
+                        return "...";
+
+                } else if (response.equals(LEARN_TEXT)) {
+                        getResponse("no", session); // cancel the prompt and return the replacement response
+                        return LEARN_RESPONSE;
+
+                } else if (response.equals(LEARN_SUGGESTION)) {
+                        return think("ok", session); // change the query
+                }
+
+                response = parseResponse(response);
+                if (response.isEmpty())
+                        return "...";
+                else
+                        return response;
+        }
+
+        @Nullable
+        @SuppressWarnings("null")
+        private static String getResponse(@Nonnull String text, @Nonnull String session) throws SAXException, IOException,
+                                                                                                                                                                         XPathExpressionException {
+                var bytes = Unirest.post("https://www.pandorabots.com/pandora/talk-xml")
+                        .field("botid", BOT_ID)
+                        .field("custid", session)
+                        .field("input", text)
+                        .asBytes()
+                        .mapBody(ByteArrayInputStream::new);
+
+                return extractResponse(bytes);
+        }
+
+        @Nonnull
+        @SuppressWarnings("null")
+        private static String parseResponse(@Nonnull String response) {
+                var parsedResponse = response;
+                for (var parser : RESPONSE_PARSERS_RECURSIVE) {
+                        Matcher m;
+                        while ((m = parser.getKey().matcher(parsedResponse)).find()) // recursive replaceAll
+                                parsedResponse = m.replaceAll(parser.getValue());
+                }
+
+                for (var parser : RESPONSE_PARSERS)
+                        parsedResponse = parser.getKey().matcher(parsedResponse).replaceAll(parser.getValue());
+
+                return StringUtils.capitalize(parsedResponse.trim());
+        }
 
+        @Nullable
+        private static synchronized String extractResponse(@Nonnull ByteArrayInputStream response) throws SAXException,
+                                                                                                                                                                                           IOException,
+                                                                                                                                                                                           XPathExpressionException {
+                var doc = DOCUMENT_BUILDER.parse(response);
+                return (String) XPATH_EXTRACTOR.evaluate(doc, STRING);
         }
 
         @Override
@@ -80,7 +183,7 @@ public class ChatbotCommand extends Command {
         public String getInfo() {
                 return """
                         Opens a chat session with \
-                        [Chomsky](http://demo.vhost.pandorabots.com/pandora/talk?botid=b0dafd24ee35a477).""";
+                        [Chomsky](http://demo.vhost.pandorabots.com/pandora/talk?botid=b0dafd24ee35a477), the online chatbot.""";
         }
 
         @Override