/*
 * Juick
 * Copyright (C) 2013, Ugnich Anton
 *
 * 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.server.CrosspostQueries;
import com.juick.xmpp.JID;
import com.juick.xmpp.Message;
import com.juick.xmpp.Stream;
import com.juick.xmpp.StreamComponent;
import com.juick.xmpp.extensions.JuickMessage;
import org.apache.commons.codec.binary.Base64;

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import javax.net.ssl.HttpsURLConnection;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import java.io.*;
import java.net.Socket;
import java.net.URL;
import java.net.URLEncoder;
import java.security.Key;
import java.sql.Connection;
import java.sql.Driver;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Enumeration;
import java.util.Properties;
import java.util.UUID;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.logging.Level;
import java.util.logging.LogManager;
import java.util.logging.Logger;

/**
 *
 * @author Ugnich Anton
 */
public class CrosspostComponent implements ServletContextListener,  Stream.StreamListener, Message.MessageListener {

    private static Logger logger = Logger.getLogger(CrosspostComponent.class.getName());

    private ExecutorService executorService;

    public final static String TWITTERURL = "https://api.twitter.com/1.1/statuses/update.json";
    public final static String FBURL = "https://graph.facebook.com/me/feed";
    public final static String VKURL = "https://api.vk.com/method/wall.post";
    Connection sql;
    Stream xmpp;
    String twitter_consumer_key;
    String twitter_consumer_secret;

    @Override
    public void contextInitialized(final ServletContextEvent sce) {
        logger.info("component initialized");
        executorService = Executors.newSingleThreadExecutor();
        executorService.submit((Runnable) () -> {
            try {
                Properties conf = new Properties();
                conf.load(sce.getServletContext().getResourceAsStream("/WEB-INF/juick.conf"));

                LogManager.getLogManager().readConfiguration(
                        sce.getServletContext().getResourceAsStream("/WEB-INF/logging.properties"));
                twitter_consumer_key = conf.getProperty("twitter_consumer_key", "");
                twitter_consumer_secret = conf.getProperty("twitter_consumer_secret", "");

                setupSql(conf.getProperty("mysql_host"), conf.getProperty("mysql_username"),
                        conf.getProperty("mysql_password", ""), conf.getProperty("mysql_database", ""));
                setupXmppComponent(conf.getProperty("xmpp_password", ""));
            } catch (Exception e) {
                logger.log(Level.SEVERE, e.getMessage(), e);
            }
        });
    }

    @Override
    public void contextDestroyed(ServletContextEvent sce) {
        // Now deregister JDBC drivers in this context's ClassLoader:
        // Get the webapp's ClassLoader
        ClassLoader cl = Thread.currentThread().getContextClassLoader();
        // Loop through all drivers
        Enumeration<Driver> drivers = DriverManager.getDrivers();
        while (drivers.hasMoreElements()) {
            Driver driver = drivers.nextElement();
            if (driver.getClass().getClassLoader() == cl) {
                // This driver was registered by the webapp's ClassLoader, so deregister it:
                try {
                    logger.info(String.format("Deregistering JDBC driver %s", driver.toString()));
                    DriverManager.deregisterDriver(driver);
                } catch (SQLException ex) {
                    logger.log(Level.SEVERE, String.format("Error deregistering JDBC driver %s", driver), ex);
                }
            } else {
                // driver was not registered by the webapp's ClassLoader and may be in use elsewhere
                logger.log(Level.SEVERE, String.format("Not deregistering JDBC driver %s as it does not belong to this webapp's ClassLoader", driver));
            }
        }
        executorService.shutdown();
        logger.info("component destroyed");
    }

    public void setupSql(String host, String username, String password, String database) {
        try {
            Class.forName("com.mysql.jdbc.Driver");
            sql = DriverManager.getConnection(
                    String.format("jdbc:mysql://%s/%s?autoReconnect=true&user=%s&password=%s",
                            host, database, username, password));
        } catch (SQLException | ClassNotFoundException e) {
            logger.log(Level.SEVERE, e.getMessage(), e);
        }
    }

    public void setupXmppComponent(String password) {
        try {
            Socket socket = new Socket("localhost", 5347);
            xmpp = new StreamComponent(new JID("", "crosspost.juick.com", ""), socket.getInputStream(), socket.getOutputStream(), password);
            xmpp.addChildParser(new JuickMessage());
            xmpp.addListener((Stream.StreamListener) this);
            xmpp.addListener((Message.MessageListener) this);
            xmpp.startParsing();
        } catch (IOException e) {
            logger.log(Level.SEVERE, e.getMessage(), e);
        }
    }

    @Override
    public void onStreamReady() {
        logger.info("XMPP STREAM READY");
    }

    @Override
    public void onStreamFail(Exception e) {logger.log(Level.SEVERE, "XMPP STREAM FAIL", e);}
    @Override
    public void onMessage(com.juick.xmpp.Message msg) {
        JuickMessage jmsg = (JuickMessage) msg.getChild(JuickMessage.XMLNS);
        if (msg.to != null && msg.to.Username != null && jmsg != null && jmsg.getRID() == 0) {
            if (msg.to.Username.equals("twitter")) {
                twitterPost(jmsg);
            } else if (msg.to.Username.equals("fb")) {
                facebookPost(jmsg);
            } else if (msg.to.Username.equals("vk")) {
                vkontaktePost(jmsg);
            }
        }
    }

    public boolean facebookPost(com.juick.Message jmsg) {
        String token = CrosspostQueries.getFacebookToken(sql, jmsg.getUser().getUID());
        if (token == null) {
            return false;
        }

        logger.info("FB: #" + jmsg.getMID());

        String status = getMessageHashTags(jmsg) + "\n" + jmsg.getText();

        boolean ret = false;
        try {
            String body = "access_token=" + URLEncoder.encode(token, "UTF-8") + "&message=" + URLEncoder.encode(status, "UTF-8") + "&link=http%3A%2F%2Fjuick.com%2F" + jmsg.getMID();

            HttpsURLConnection conn = (HttpsURLConnection) new URL(FBURL).openConnection();
            conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
            conn.setRequestProperty("User-Agent", "Juick");
            conn.setRequestProperty("Content-Length", Integer.toString(body.length()));
            conn.setUseCaches(false);
            conn.setDoInput(true);
            conn.setDoOutput(true);
            conn.setRequestMethod("POST");
            conn.connect();

            OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
            wr.write(body);
            wr.close();

            ret = streamToString(conn.getInputStream()) != null;

            conn.disconnect();
        } catch (Exception e) {
            logger.log(Level.SEVERE, "fbPost: " + e.getMessage(), e);
        }
        return ret;
    }

    public boolean vkontaktePost(com.juick.Message jmsg) {
        String tokens[] = CrosspostQueries.getVKTokens(sql, jmsg.getUser().getUID());
        if (tokens == null || tokens.length != 2) {
            return false;
        }

        logger.info("VK: #" + jmsg.getMID());

        String status = getMessageHashTags(jmsg) + "\n" + jmsg.getText() + "\nhttp://juick.com/" + jmsg.getMID();

        boolean ret = false;
        try {
            String body = "owner_id=" + tokens[0] + "&access_token=" + URLEncoder.encode(tokens[1], "UTF-8") + "&from_group=1&message=" + URLEncoder.encode(status, "UTF-8");

            HttpsURLConnection conn = (HttpsURLConnection) new URL(VKURL).openConnection();
            conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
            conn.setRequestProperty("User-Agent", "Juick");
            conn.setRequestProperty("Content-Length", Integer.toString(body.length()));
            conn.setUseCaches(false);
            conn.setDoInput(true);
            conn.setDoOutput(true);
            conn.setRequestMethod("POST");
            conn.connect();

            OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
            wr.write(body);
            wr.close();

            ret = streamToString(conn.getInputStream()) != null;

            conn.disconnect();
        } catch (Exception e) {
            logger.log(Level.SEVERE, "vkPost: " + e.getMessage(), e);
        }
        return ret;
    }

    public boolean twitterPost(com.juick.Message jmsg) {
        String tokens[] = CrosspostQueries.getTwitterTokens(sql, jmsg.getUser().getUID());
        if (tokens == null || tokens.length != 2) {
            return false;
        }
        String token = percentEncode(tokens[0]);
        String token_secret = percentEncode(tokens[1]);

        logger.info("TWITTER: #" + jmsg.getMID());

        String status = getMessageHashTags(jmsg) + jmsg.getText();
        if (status.length() > 115) {
            status = status.substring(0, 114) + "…";
        }
        status += " http://juick.com/" + jmsg.getMID();
        status = percentEncode(status);

        boolean ret = false;
        try {
            String nonce = UUID.randomUUID().toString();
            String timestamp = Long.toString(System.currentTimeMillis() / 1000L);
            String signature = percentEncode(twitterSignature(status, nonce, timestamp, token, token_secret));
            String auth = "OAuth "
                    + "oauth_consumer_key=\"" + twitter_consumer_key + "\", "
                    + "oauth_nonce=\"" + nonce + "\", "
                    + "oauth_signature=\"" + signature + "\", "
                    + "oauth_signature_method=\"HMAC-SHA1\", "
                    + "oauth_timestamp=\"" + timestamp + "\", "
                    + "oauth_token=\"" + token + "\", "
                    + "oauth_version=\"1.0\"";

            HttpsURLConnection conn = (HttpsURLConnection) new URL(TWITTERURL).openConnection();
            conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
            conn.setRequestProperty("User-Agent", "Juick");
            conn.setRequestProperty("Content-Length", Integer.toString(status.length() + 7));
            conn.setRequestProperty("Authorization", auth);
            conn.setUseCaches(false);
            conn.setDoInput(true);
            conn.setDoOutput(true);
            conn.setRequestMethod("POST");
            conn.connect();

            OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
            wr.write("status=" + status);
            wr.close();

            ret = streamToString(conn.getInputStream()) != null;

            conn.disconnect();
        } catch (Exception e) {
            logger.log(Level.SEVERE, "twitterPost: " + e.getMessage(), e);
        }
        return ret;
    }

    public String twitterSignature(String status, String nonce, String timestamp, String token, String token_secret) {
        try {
            // ALPHABET-SORTED
            String params = "oauth_consumer_key=" + twitter_consumer_key
                    + "&oauth_nonce=" + nonce
                    + "&oauth_signature_method=HMAC-SHA1"
                    + "&oauth_timestamp=" + timestamp
                    + "&oauth_token=" + token
                    + "&oauth_version=1.0"
                    + "&status=" + status;

            String base = "POST&" + percentEncode(TWITTERURL) + "&" + percentEncode(params);
            String key = twitter_consumer_secret + "&" + token_secret;

            Key signingKey = new SecretKeySpec(key.getBytes(), "HmacSHA1");
            Mac mac = Mac.getInstance("HmacSHA1");
            mac.init(signingKey);
            byte[] rawHmac = mac.doFinal(base.getBytes());
            return Base64.encodeBase64String(rawHmac);

        } catch (Exception e) {
            logger.log(Level.SEVERE, "twitterSignature: " + e.getMessage(), e);
        }
        return null;
    }

    public String streamToString(InputStream is) {
        try {
            BufferedReader buf = new BufferedReader(new InputStreamReader(is));
            StringBuilder str = new StringBuilder();
            String line;
            do {
                line = buf.readLine();
                str.append(line).append("\n");
            } while (line != null);
            return str.toString();
        } catch (Exception e) {
            logger.log(Level.SEVERE, "streamToString: " + e.getMessage(), e);
        }
        return null;
    }

    public String getMessageHashTags(com.juick.Message jmsg) {
        String hashtags = "";
        for (int i = 0; i < jmsg.Tags.size(); i++) {
            hashtags += "#" + jmsg.Tags.get(i) + " ";
        }
        return hashtags;
    }

    public static String percentEncode(String s) {
        String ret = "";
        try {
            ret = URLEncoder.encode(s, "UTF-8").replace("+", "%20").replace("*", "%2A").replace("%7E", "~");
        } catch (UnsupportedEncodingException e) {
        }
        return ret;
    }
}