/*
 * Copyright (C) 2008-2022, Juick
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package com.juick;

import com.juick.model.CommandResult;
import com.juick.model.User;
import com.juick.service.MessagesService;
import com.juick.service.ChatService;
import com.juick.service.StorageService;
import com.juick.service.UserService;
import com.juick.service.component.NotificationListener;
import com.juick.service.component.PingEvent;
import com.juick.service.component.SystemEvent;
import com.juick.util.MessageUtils;
import com.juick.util.formatters.PlainTextFormatter;
import com.juick.util.xmpp.iq.MessageQuery;
import com.juick.www.api.SystemActivity;
import org.apache.commons.codec.digest.DigestUtils;
import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.io.Resource;
import rocks.xmpp.addr.Jid;
import rocks.xmpp.core.XmppException;
import rocks.xmpp.core.session.Extension;
import rocks.xmpp.core.session.XmppSession;
import rocks.xmpp.core.session.XmppSessionConfiguration;
import rocks.xmpp.core.session.debug.LogbackDebugger;
import rocks.xmpp.core.stanza.IQHandler;
import rocks.xmpp.core.stanza.model.IQ;
import rocks.xmpp.core.stanza.model.Message;
import rocks.xmpp.core.stanza.model.Presence;
import rocks.xmpp.core.stanza.model.StanzaError;
import rocks.xmpp.core.stanza.model.client.ClientMessage;
import rocks.xmpp.core.stanza.model.client.ClientPresence;
import rocks.xmpp.core.stanza.model.errors.Condition;
import rocks.xmpp.extensions.caps.client.ClientEntityCapabilities1Protocol;
import rocks.xmpp.extensions.component.accept.ExternalComponent;
import rocks.xmpp.extensions.disco.ServiceDiscoveryManager;
import rocks.xmpp.extensions.disco.model.info.Identity;
import rocks.xmpp.extensions.filetransfer.FileTransfer;
import rocks.xmpp.extensions.filetransfer.FileTransferManager;
import rocks.xmpp.extensions.nick.model.Nickname;
import rocks.xmpp.extensions.oob.model.x.OobX;
import rocks.xmpp.extensions.ping.PingManager;
import rocks.xmpp.extensions.receipts.MessageDeliveryReceiptsManager;
import rocks.xmpp.extensions.vcard.temp.model.VCard;
import rocks.xmpp.extensions.version.SoftwareVersionManager;
import rocks.xmpp.extensions.version.model.SoftwareVersion;

import javax.annotation.Nonnull;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.time.Duration;
import java.time.LocalDate;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.function.BiFunction;

/**
 * @author ugnich
 */
public class XMPPManager implements NotificationListener {
    private static final Logger logger = LoggerFactory.getLogger("XMPP");
    private final ExternalComponent xmpp;
    private final CommandsManager commandsManager;
    private final MessagesService messagesService;
    private final UserService userService;
    private final ChatService chatService;
    private final Jid jid;
    public XMPPManager(String botJid, String componentName, int componentPort, String componentHost,
                       String password, Resource vCardImage, CommandsManager commandsManager,
                       StorageService storageService, MessagesService messagesService, UserService userService,
                       ChatService chatService, Executor applicationTaskExecutor) {
        jid = Jid.of(botJid);
        this.commandsManager = commandsManager;
        this.messagesService = messagesService;
        this.userService = userService;
        this.chatService = chatService;
        logger.info("xmpp component start connecting to {}", componentPort);
        XmppSessionConfiguration configuration = XmppSessionConfiguration.builder()
                .extensions(Extension.of(com.juick.model.Message.class), Extension.of(MessageQuery.class))
                .debugger(LogbackDebugger.class)
                .defaultResponseTimeout(Duration.ofMillis(120000))
                .build();
        xmpp = ExternalComponent.create(componentName, password, configuration, componentHost, componentPort);
        ServiceDiscoveryManager serviceDiscoveryManager = xmpp.getManager(ServiceDiscoveryManager.class);
        serviceDiscoveryManager.addIdentity(Identity.clientBot().withName("Juick"));
        xmpp.getManager(ClientEntityCapabilities1Protocol.class).setNode("https://juick.com/caps");
        MessageDeliveryReceiptsManager messageDeliveryReceiptsManager = xmpp.getManager(MessageDeliveryReceiptsManager.class);
        messageDeliveryReceiptsManager.setEnabled(true);
        PingManager pingManager = xmpp.getManager(PingManager.class);
        pingManager.setEnabled(true);
        SoftwareVersionManager softwareVersionManager = xmpp.getManager(SoftwareVersionManager.class);
        softwareVersionManager.setSoftwareVersion(new SoftwareVersion("Juick", "2.x",
                System.getProperty("os.name", "generic")));
        VCard vCard = new VCard();
        vCard.setFormattedName("Juick");
        vCard.setBirthday(LocalDate.of(2008, 10, 22));
        try {
            vCard.setUrl(new URL("http://juick.com/"));
            vCard.setPhoto(new VCard.Image("image/png", IOUtils.toByteArray(vCardImage.getInputStream())));
        } catch (MalformedURLException e) {
            logger.error("invalid url", e);
        } catch (IOException e) {
            logger.warn("invalid resource", e);
        }
        xmpp.addIQHandler(new IQHandler() {
            public java.lang.Class<?> getPayloadClass() {
                return MessageQuery.class;
            }
            public IQ handleRequest(IQ iq) {
                Message warningMessage = new Message(iq.getFrom(), Message.Type.CHAT);
                warningMessage.setFrom(jid);
                warningMessage.setBody("Please, stop this shit");
                xmpp.send(warningMessage);
                return iq.createError(new StanzaError(Condition.BAD_REQUEST, "Please stop this spam"));
            }
        });
        xmpp.addIQHandler(new IQHandler() {
            public Class<?> getPayloadClass() {
                return VCard.class;
            }
            @Override
            public IQ handleRequest(IQ iq) {
                if (isValidTarget(iq.getTo(), true)) {
                    return iq.createResult(vCard);
                }
                return iq.createError(Condition.BAD_REQUEST);
            }
        });
        xmpp.addInboundMessageListener(e -> {
            ClientMessage result = incomingMessage(e.getMessage());
            if (result != null) {
                xmpp.send(result);
            }
        });
        FileTransferManager fileTransferManager = xmpp.getManager(FileTransferManager.class);
        fileTransferManager.addFileTransferOfferListener(e -> {
            try {
                List<String> allowedTypes = List.of("png", "jpg");
                String attachmentExtension = FilenameUtils.getExtension(e.getName()).toLowerCase();
                String targetFilename = String.format("%s.%s",
                        DigestUtils.md5Hex(String.format("%s-%s",
                                e.getInitiator().toString(), e.getSessionId()).getBytes()), attachmentExtension);
                if (allowedTypes.contains(attachmentExtension)) {
                    Path filePath = Paths.get(storageService.getTemporaryDirectory(), targetFilename);
                    FileTransfer ft = e.accept(filePath).get();
                    ft.addFileTransferStatusListener(st -> {
                        logger.debug("{}: received {} of {}", e.getName(), st.getBytesTransferred(), e.getSize());
                        if (st.getStatus().equals(FileTransfer.Status.COMPLETED)) {
                            logger.info("transfer completed");
                            try {
                                Jid initiator = e.getInitiator();
                                ClientMessage result = handleCommand(
                                        userService.getUserByJID(initiator.asBareJid().toEscapedString()), initiator,
                                        StringUtils.defaultString(e.getDescription()).trim(), URI.create(String.format("juick://%s", targetFilename)));
                                if (result != null) {
                                    xmpp.send(result);
                                }
                            } catch (Exception e1) {
                                logger.error("ft error", e1);
                            }

                        } else if (st.getStatus().equals(FileTransfer.Status.FAILED)) {
                            logger.info("transfer failed", ft.getException());
                            Message msg = new Message();
                            msg.setType(Message.Type.CHAT);
                            msg.setFrom(jid);
                            msg.setTo(e.getInitiator());
                            msg.setBody("File transfer failed, please report to us");
                            xmpp.sendMessage(msg);
                        } else if (st.getStatus().equals(FileTransfer.Status.CANCELED)) {
                            logger.info("transfer cancelled");
                        }
                    });
                    ft.transfer();
                    logger.info("transfer started");
                } else {
                    e.reject();
                    logger.info("transfer rejected");
                }
            } catch (IOException | InterruptedException | ExecutionException e1) {
                logger.error("ft error", e1);
            }
        });
        xmpp.addConnectionListener(event -> {
            if (event.getType().equals(rocks.xmpp.core.session.ConnectionEvent.Type.RECONNECTION_SUCCEEDED)) {
                logger.info("component connected");
            }
        });
        xmpp.addSessionStatusListener(event -> {
            logger.info("event: " + event.getStatus(), event.getThrowable());
            if (event.getStatus().equals(XmppSession.Status.AUTHENTICATED)) {
                logger.info("Authenticated, broadcasting...");
                broadcastPresence(null);
            }
        });
        xmpp.addInboundPresenceListener(event -> {
            incomingPresence(event.getPresence());
        });
        applicationTaskExecutor.execute(() -> {
            try {
                xmpp.connect();
            } catch (XmppException e) {
                logger.warn("xmpp exception", e);
            }
        });
    }

    private boolean isValidTarget (Jid from, boolean allowDomain) {
        var isBotJid = from.equals(jid) || from.asBareJid().equals(jid.asBareJid());
        var isDomainJid = from.asBareJid().toEscapedString().equals(jid.getDomain());
        if (allowDomain) {
            return isBotJid || isDomainJid;
        }
        return isBotJid;
    };

    private void sendJuickMessage(com.juick.model.Message jmsg, List<User> users) {
        List<String> jids = new ArrayList<>();

        for (User user : users) {
            jids.addAll(userService.getJIDsbyUID(user.getUid()));
        }
        com.juick.model.Message fullMsg = messagesService.getMessage(jmsg.getMid()).orElseThrow(IllegalStateException::new);
        String txt = "@" + jmsg.getUser().getName() + ":" + MessageUtils.getTagsString(fullMsg) + "\n";
        String attachmentUrl = MessageUtils.attachmentUrl(fullMsg);
        if (StringUtils.isNotEmpty(attachmentUrl)) {
            txt += attachmentUrl + "\n";
        }
        txt += StringUtils.defaultString(jmsg.getText()) + "\n\n";
        txt += "#" + jmsg.getMid() + " http://juick.com/m/" + jmsg.getMid();

        Nickname nick = new Nickname("@" + jmsg.getUser().getName());

        Message msg = new Message();
        msg.setFrom(jid);
        msg.setBody(txt);
        msg.setType(Message.Type.CHAT);
        msg.setThread("juick-" + jmsg.getMid());
        msg.addExtension(jmsg);
        msg.addExtension(nick);
        if (StringUtils.isNotEmpty(attachmentUrl)) {
            try {
                OobX oob = new OobX(new URI(attachmentUrl));
                msg.addExtension(oob);
            } catch (URISyntaxException e) {
                logger.warn("uri exception", e);
            }
        }
        for (String jid : jids) {
            msg.setTo(Jid.of(jid));
            xmpp.send(ClientMessage.from(msg));
        }
    }

    private void sendJuickComment(com.juick.model.Message jmsg, List<User> users) {
        String replyQuote;
        String replyTo;

        com.juick.model.Message replyMessage = jmsg.getReplyto() > 0 ? messagesService.getReply(jmsg.getMid(), jmsg.getReplyto())
                : messagesService.getMessage(jmsg.getMid()).orElseThrow(IllegalStateException::new);
        replyTo = replyMessage.getUser().getName();
        com.juick.model.Message fullReply = messagesService.getReply(jmsg.getMid(), jmsg.getRid());
        replyQuote = StringUtils.defaultString(fullReply.getReplyQuote());

        String txt = "Reply by @" + jmsg.getUser().getName() + ":\n" + replyQuote + "\n@" + replyTo + " ";
        String attachmentUrl = MessageUtils.attachmentUrl(fullReply);
        if (StringUtils.isNotEmpty(attachmentUrl)) {
            txt += attachmentUrl + "\n";
        }
        txt += StringUtils.defaultString(jmsg.getText()) + "\n\n" + "#" + jmsg.getMid() + "/" + jmsg.getRid() + " http://juick.com/m/" + jmsg.getMid() + "#" + jmsg.getRid();

        Message msg = new Message();
        msg.setFrom(jid);
        msg.setBody(txt);
        msg.setType(Message.Type.CHAT);
        msg.addExtension(jmsg);
        for (User user : users) {
            for (String jid : userService.getJIDsbyUID(user.getUid())) {
                msg.setTo(Jid.of(jid));
                xmpp.send(ClientMessage.from(msg));
            }
        }
    }

    @Override
    public void processSystemEvent(SystemEvent systemEvent) {
        var activity = systemEvent.getActivity();
        var type = activity.getType();
        if (type.equals(SystemActivity.ActivityType.message)) {
            processMessage(activity.getMessage(), activity.getTo());
        } else if (type.equals(SystemActivity.ActivityType.like)) {
            processLike(activity.getFrom(), activity.getMessage(), activity.getTo());
        }
    }

    private void processMessage(com.juick.model.Message msg, List<User> subscribers) {
        if (msg.isService()) {
            return;
        }
        if (MessageUtils.isPM(msg)) {
            userService.getJIDsbyUID(msg.getTo().getUid())
                    .forEach(userJid -> {
                        Message mm = new Message();
                        mm.setTo(Jid.of(userJid));
                        mm.setType(Message.Type.CHAT);
                        mm.setFrom(jid);
                        mm.setBody("Private message from @" + msg.getUser().getName() + ":\n" + msg.getText());
                        xmpp.send(ClientMessage.from(mm));
                    });
        } else if (MessageUtils.isReply(msg)) {
            sendJuickComment(msg, subscribers);
        } else {
            sendJuickMessage(msg, subscribers);
        }
    }

    private ClientMessage makeReply(Jid jidTo, String txt) {
        Message reply = new Message();
        reply.setFrom(jid);
        reply.setTo(jidTo);
        reply.setType(Message.Type.CHAT);
        reply.setBody(txt);
        return ClientMessage.from(reply);
    }

    public void processLike(User liker, com.juick.model.Message jmsg, List<User> users) {
        if (!userService.isInBLAny(jmsg.getUser().getUid(), liker.getUid())) {
            userService.getJIDsbyUID(jmsg.getUser().getUid()).forEach(authorJid -> {
                try {
                    Jid toJid = Jid.of(authorJid);
                    Message xmppMessage = new Message();
                    xmppMessage.setFrom(jid);
                    xmppMessage.setTo(toJid);
                    xmppMessage.setType(Message.Type.CHAT);
                    xmppMessage.addExtension(jmsg);
                    xmppMessage.setBody(String.format("%s recommended your post #%d. %s",
                            liker.getName(), jmsg.getMid(), PlainTextFormatter.formatUrl(jmsg)));
                    xmpp.send(ClientMessage.from(xmppMessage));
                } catch (IllegalArgumentException e) {
                    logger.warn("{}: {}", authorJid, e.getMessage());
                }
            });
        }

        String txt = "Recommended by @" + liker.getName() + ":\n";
        txt += "@" + jmsg.getUser().getName() + ":" + MessageUtils.getTagsString(jmsg) + "\n";
        String attachmentUrl = MessageUtils.attachmentUrl(jmsg);
        if (StringUtils.isNotEmpty(attachmentUrl)) {
            txt += attachmentUrl + "\n";
        }
        txt += StringUtils.defaultString(jmsg.getText()) + "\n\n";
        txt += "#" + jmsg.getMid();
        if (jmsg.getReplies() > 0) {
            if (jmsg.getReplies() % 10 == 1 && jmsg.getReplies() % 100 != 11) {
                txt += " (" + jmsg.getReplies() + " reply)";
            } else {
                txt += " (" + jmsg.getReplies() + " replies)";
            }
        }
        txt += " http://juick.com/m/" + jmsg.getMid();

        Nickname nick = new Nickname("@" + jmsg.getUser().getName());

        Message msg = new Message();
        msg.setFrom(jid);
        msg.setBody(txt);
        msg.setType(Message.Type.CHAT);
        msg.setThread("juick-" + jmsg.getMid());
        msg.addExtension(jmsg);
        msg.addExtension(nick);
        if (StringUtils.isNotEmpty(attachmentUrl)) {
            try {
                OobX oob = new OobX(new URI(attachmentUrl));
                msg.addExtension(oob);
            } catch (URISyntaxException e) {
                logger.warn("uri exception", e);
            }
        }

        for (User user : users) {
            for (String jid : userService.getJIDsbyUID(user.getUid())) {
                msg.setTo(Jid.of(jid));
                xmpp.send(ClientMessage.from(msg));
            }
        }
    }

    @Override
    public void processPingEvent(PingEvent pingEvent) {
        userService.getJIDsbyUID(pingEvent.getPinger().getUid())
                .forEach(userJid -> {
                    Presence p = new Presence(Jid.of(userJid));
                    p.setFrom(jid);
                    p.setPriority((byte) 10);
                    xmpp.send(ClientPresence.from(p));
                });
    }

    private void incomingPresence(Presence p) {
        final boolean toJuick = isValidTarget(p.getTo(), false);
        if (p.getType() == null) {
            Presence reply = new Presence();
            reply.setFrom(p.getTo().asBareJid());
            reply.setTo(p.getFrom().asBareJid());
            reply.setType(Presence.Type.UNSUBSCRIBE);
            xmpp.send(ClientPresence.from(reply));
        } else if (p.getType().equals(Presence.Type.PROBE)) {
            if (toJuick) {
                User visitor = userService.getUserByJID(p.getFrom().asBareJid().toEscapedString());
                if (visitor != null) {
                    userService.updateLastSeen(visitor);
                }
            }
            if (toJuick) {
                Presence reply = new Presence();
                reply.setFrom(p.getTo().withResource(jid.getResource()));
                reply.setTo(p.getFrom());
                reply.setPriority((byte) 10);
                if (!userService.getActiveJIDs().contains(p.getFrom().asBareJid().toEscapedString())) {
                    reply.setStatus("Send ON to enable notifications");
                }
                xmpp.send(ClientPresence.from(reply));
            } else {
                Presence reply = new Presence();
                reply.setFrom(p.getTo());
                reply.setTo(p.getFrom());
                reply.setType(Presence.Type.ERROR);
                reply.setId(p.getId());
                reply.setError(new StanzaError(StanzaError.Type.CANCEL, Condition.ITEM_NOT_FOUND));
                xmpp.send(ClientPresence.from(reply));
            }
        } else if (p.getType().equals(Presence.Type.SUBSCRIBE)) {
            if (toJuick) {
                Presence reply = new Presence();
                reply.setFrom(p.getTo());
                reply.setTo(p.getFrom());
                reply.setType(Presence.Type.SUBSCRIBED);
                xmpp.send(ClientPresence.from(reply));

                reply.setFrom(reply.getFrom().withResource(jid.getResource()));
                reply.setPriority((byte) 10);
                reply.setType(null);
                xmpp.send(ClientPresence.from(reply));
            } else {
                Presence reply = new Presence();
                reply.setFrom(p.getTo());
                reply.setTo(p.getFrom());
                reply.setType(Presence.Type.ERROR);
                reply.setId(p.getId());
                reply.setError(new StanzaError(StanzaError.Type.CANCEL, Condition.ITEM_NOT_FOUND));
                xmpp.send(ClientPresence.from(reply));
            }
        } else if (p.getType().equals(Presence.Type.UNSUBSCRIBE)) {
            Presence reply = new Presence();
            reply.setFrom(p.getTo());
            reply.setTo(p.getFrom());
            reply.setType(Presence.Type.UNSUBSCRIBED);
            xmpp.send(ClientPresence.from(reply));
        } else if (p.getType().equals(Presence.Type.ERROR)) {
            StanzaError error = p.getError();
            if (error != null && error.getCondition().equals(Condition.REMOTE_SERVER_NOT_FOUND)) {
                if (userService.setActiveStatusForJID(p.getFrom().toEscapedString(), UserService.ActiveStatus.Inactive)) {
                    logger.info("{} is inactive now", p.getFrom());
                }
            }
        }
    }

    public ClientMessage incomingMessage(Message msg) {
        if (msg.getType() != null && msg.getType().equals(Message.Type.ERROR)) {
            StanzaError error = msg.getError();
            if (error != null) {
                var shouldDeactivate = error.getCondition().equals(Condition.RESOURCE_CONSTRAINT)
                        || error.getType().equals(StanzaError.Type.CANCEL);
                if (shouldDeactivate) {
                    if (userService.setActiveStatusForJID(msg.getFrom().toEscapedString(),
                            UserService.ActiveStatus.Inactive)) {
                        logger.info("{} is inactive now", msg.getFrom());
                        return null;
                    }
                }
            }
            return null;
        }
        Jid to = msg.getTo();
        if (isValidTarget(to, false)) {
            User user_from = userService.getUserByJID(msg.getFrom().asBareJid().toEscapedString());
            if ((user_from == null || user_from.isAnonymous())) {
                return makeReply(msg.getFrom(), "XMPP registrations are disabled");
            }
            URI attachment = URI.create(StringUtils.EMPTY);
            OobX oobX = msg.getExtension(OobX.class);
            if (oobX != null) {
                attachment = oobX.getUri();
            }
            try {
                return handleCommand(user_from, msg.getFrom(), StringUtils.defaultString(msg.getBody()).trim(), attachment);
            } catch (Exception e1) {
                logger.warn("message exception", e1);
            }
        }
        ClientMessage errorMessage = ClientMessage.from(msg);
        errorMessage.setError(new StanzaError(StanzaError.Type.CANCEL, Condition.ITEM_NOT_FOUND));
        return errorMessage;
    }

    private ClientMessage handleCommand(User user_from, Jid from, String command, @Nonnull URI attachment) {
        if (StringUtils.isBlank(command) && attachment.toString().isEmpty()) {
            return null;
        }

        messagesService.getUnread(user_from).forEach(mid -> messagesService.setRead(user_from, mid));

        int commandlen = command.length();

        // COMPATIBILITY
        if (commandlen > 7 && command.substring(0, 3).equalsIgnoreCase("PM ")) {
            command = command.substring(3);
        }

        try {
            CommandResult result = commandsManager.processCommand(user_from, command, attachment);
            if (StringUtils.isNotBlank(result.getText())) {
                return makeReply(from, result.getText());
            }
        } catch (Exception e) {
            logger.warn("xmpp command exception", e);
            return makeReply(from, "Error processing command");
        }
        return null;
    }

    private void broadcastPresence(Presence.Type type) {
        Presence presence = new Presence();
        presence.setFrom(jid);
        if (type != null) {
            presence.setType(type);
        }
        userService.getActiveJIDs().forEach(j -> {
            try {
                presence.setTo(Jid.of(j));
                xmpp.send(ClientPresence.from(presence));
            } catch (IllegalArgumentException ex) {
                logger.warn("Invalid jid: {}", j, ex);
            }
        });
    }

    public void close() throws Exception {
        broadcastPresence(Presence.Type.UNAVAILABLE);
        if (xmpp != null) {
            xmpp.close();
        }
    }
}