/*
 * Juick
 * Copyright (C) 2008-2013, ugnich
 *
 * 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.rss;

import com.juick.Message;
import com.juick.server.MessagesQueries;
import com.juick.server.UserQueries;
import org.apache.commons.dbcp2.BasicDataSource;
import org.apache.commons.lang3.math.NumberUtils;
import org.springframework.jdbc.core.JdbcTemplate;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.Properties;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * @author ugnich
 */
@WebServlet(name = "Main", urlPatterns = {"/"})
public class Main extends HttpServlet {

    private static final SimpleDateFormat sdfRSS = new SimpleDateFormat("EEE, d MMM yyyy HH:mm:ss Z");
    JdbcTemplate sql;

    @Override
    public void init() throws ServletException {
        super.init();
        try {
            Properties conf = new Properties();
            conf.load(getServletContext().getResourceAsStream("/WEB-INF/juick.conf"));
            BasicDataSource dataSource = new BasicDataSource();
            dataSource.setDriverClassName(conf.getProperty("datasource_driver", "com.mysql.jdbc.Driver"));
            dataSource.setUrl(conf.getProperty("datasource_url"));
            sql = new JdbcTemplate(dataSource);

        } catch (Exception e) {
            log(null, e);
        }
    }

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        if (request.getCharacterEncoding() == null) {
            request.setCharacterEncoding("UTF-8");
        }

        String uri = request.getRequestURI();
        if (uri.equals("/")) {
            int hours = NumberUtils.toInt(request.getParameter("hours"), 0);
            if (hours > 0 && hours < 13) {
                List<Integer> mids = getLastMessages(hours);
                List<Message> msgs = MessagesQueries.getMessages(sql, mids);
                responseMessages(response, 0, null, msgs);
            } else {
                response.sendError(404);
            }
        } else if (uri.equals("/comments")) {
            int hours = NumberUtils.toInt(request.getParameter("hours"), 0);
            if (hours > 0 && hours < 13) {
                responseReplies(response, hours);
            } else {
                response.sendError(404);
            }
        } else if (uri.matches("^/[a-zA-Z0-9\\-]{2,16}/blog$")) {
            String uname = uri.substring(1, uri.length() - 5);
            int uid = UserQueries.getUIDbyName(sql, uname);
            if (uid > 0) {
                List<Integer> mids = MessagesQueries.getUserBlog(sql, uid, 0, 0);
                if (!mids.isEmpty()) {
                    List<Message> msgs = MessagesQueries.getMessages(sql, mids);
                    responseMessages(response, uid, uname, msgs);
                } else {
                    response.sendError(404);
                }
            } else {
                response.sendError(404);
            }
        } else {
            response.sendError(404);
        }
    }

    private void responseMessages(HttpServletResponse response, int uid, String uname, List<Message> msgs) throws IOException {
        response.setContentType("application/rss+xml; charset=UTF-8");

        try (PrintWriter out = response.getWriter()) {
            out.println("<?xml version='1.0' encoding='utf-8'?>");
            out.println("<rss version='2.0' xmlns:atom='http://www.w3.org/2005/Atom' xmlns:slash='http://purl.org/rss/1.0/modules/slash/' xmlns:rdf='http://www.w3.org/1999/02/22-rdf-syntax-ns#' xmlns:media='http://search.yahoo.com/mrss/'  xmlns:juick='http://juick.com/'>");
            out.println("<channel>");
            if (uid > 0) {
                out.println("<atom:link href='http://rss.juick.com/" + uname + "/blog' rel='self' type='application/rss+xml'/>");
                out.println("<title>" + uname + " - Juick</title>");
                out.println("<link>http://juick.com/" + uname + "/</link>");
                out.println("<description>The latest messages by @" + uname + " at Juick</description>");
                out.println("<image><url>http://i.juick.com/a/" + uid + ".png</url><title>" + uname + " - Juick</title><link>http://juick.com/" + uname + "/</link></image>");
            } else {
                out.println("<title>Juick</title>");
                out.println("<link>http://juick.com/</link>");
                out.println("<description>The latest messages at Juick</description>");
            }

            for (Message msg : msgs) {
                out.println("<item>");
                out.println("<link>http://juick.com/" + msg.getUser().getName() + "/" + msg.getMid() + "</link>");
                out.println("<guid>http://juick.com/" + msg.getUser().getName() + "/" + msg.getMid() + "</guid>");

                out.print("<title><![CDATA[@" + msg.getUser().getName() + ":");
                if (!msg.getTags().isEmpty()) {
                    for (int n = 0; n < msg.getTags().size(); n++) {
                        out.print(" *" + msg.getTags().get(n));
                    }
                }
                out.println("]]></title>");
                out.println("<description><![CDATA[" + formatMessage(msg.getText()) + "]]></description>");

                out.println("<pubDate>" + sdfRSS.format(msg.getDate()) + "</pubDate>");

                out.println("<comments>http://juick.com/" + msg.getUser().getName() + "/" + msg.getMid() + "</comments>");
                if (!msg.getTags().isEmpty()) {
                    for (int n = 0; n < msg.getTags().size(); n++) {
                        out.println("<category>" + escapeHtml(msg.getTags().get(n).getName()) + "</category>");
                    }
                }
                if (msg.AttachmentType != null) {
                    if (msg.AttachmentType.equals("jpg")) {
                        out.println("<media:content url='http://i.juick.com/photos-1024/" + msg.getMid() + ".jpg' type='image/jpeg'/>");
                        out.println("<media:thumbnail url='http://i.juick.com/ps/" + msg.getMid() + ".jpg'/>");
                    } else if (msg.AttachmentType.equals("png")) {
                        out.println("<media:content url='http://i.juick.com/photos-1024/" + msg.getMid() + ".png' type='image/png'/>");
                        out.println("<media:thumbnail url='http://i.juick.com/ps/" + msg.getMid() + ".png'/>");
                    }
                }
                out.println("<juick:user uid='" + msg.getUser().getUid() + "'/>");
                out.println("</item>");
            }

            out.println("</channel></rss>");
        }
    }

    private class ResponseReply {
        String muname;
        int mid;
        int rid;
        String uname;
        String description;
        Date pubDate;
        String attachmentType;
    }

    private void responseReplies(HttpServletResponse response, int hours) throws IOException {
        response.setContentType("application/rss+xml; charset=UTF-8");

        try (PrintWriter out = response.getWriter()) {

            out.println("<?xml version=\"1.0\" encoding=\"utf-8\"?>");
            out.println("<rss version=\"2.0\" xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\" xmlns:ya=\"http://blogs.yandex.ru/yarss/\" xmlns:media=\"http://search.yahoo.com/mrss/\">");
            out.println("<channel>");
            out.println("<title>Juick</title>");
            out.println("<link>http://juick.com/</link>");
            out.println("<description>The latest comments at Juick</description>");

            sql.query("SELECT users2.nick,replies.message_id,replies.reply_id," +
                    "users.nick,replies.txt," +
                    "replies.ts,replies.attach,replies.ts+0 " +
                    "FROM ((replies INNER JOIN users ON replies.user_id=users.id) " +
                    "INNER JOIN messages ON replies.message_id=messages.message_id) " +
                    "INNER JOIN users AS users2 ON messages.user_id=users2.id " +
                    "WHERE replies.ts>TIMESTAMPADD(HOUR,?,NOW()) AND messages.privacy>0", (rs, rowNum) -> {
                ResponseReply reply = new ResponseReply();
                reply.muname = rs.getString(1);
                reply.mid = rs.getInt(2);
                reply.rid = rs.getInt(3);
                reply.uname = rs.getString(4);
                reply.description = rs.getString(5);
                reply.pubDate = rs.getTimestamp(6);
                reply.attachmentType = rs.getString(7);
                return reply;
            }, -hours).stream().forEach(r -> {
                out.println("<item>");
                out.println("<ya:post>http://juick.com/" + r.muname + "/" + r.mid + "</ya:post>");
                out.println("<link>http://juick.com/" + r.muname + "/" + r.mid + "#" + r.rid + "</link>");
                out.println("<guid>http://juick.com/" + r.muname + "/" + r.mid + "#" + r.rid + "</guid>");
                out.println("<author>http://juick.com/" + r.uname + "/</author>");
                out.println("<title>@" + r.uname + ":</title>");
                out.println("<description><![CDATA[" + formatMessage(r.description) + "]]></description>");
                out.println("<pubDate>" + sdfRSS.format(r.pubDate) + "</pubDate>");
                String attachment = r.attachmentType;
                if (attachment != null && !attachment.isEmpty()) {
                    if (attachment.equals("jpg")) {
                        out.println("<media:content url='http://i.juick.com/photos-1024/" + r.mid + "-" + r.rid + ".jpg' type='image/jpeg'/>");
                        out.println("<media:thumbnail url='http://i.juick.com/ps/" + r.mid + "-" + r.rid + ".jpg'/>");
                    } else if (attachment.equals("png")) {
                        out.println("<media:content url='http://i.juick.com/photos-1024/" + r.mid + "-" + r.rid + ".png' type='image/png'/>");
                        out.println("<media:thumbnail url='http://i.juick.com/ps/" + r.mid + "-" + r.rid + ".png'/>");
                    }
                }
                out.println("</item>");
            });
            out.println("</channel></rss>");
        }
    }

    private List<Integer> getLastMessages(int hours) {
        return sql.queryForList("SELECT message_id FROM messages WHERE messages.ts>TIMESTAMPADD(HOUR,?,NOW())",
                Integer.class, -hours);
    }

    private static Pattern regexLinks2 = Pattern.compile("((?<=\\s)|(?<=\\A))([\\[\\{]|&lt;)((?:ht|f)tps?://(?:www\\.)?([^\\/\\s\\\"\\)\\!]+)/?(?:[^\\]\\}](?<!&gt;))*)([\\]\\}]|&gt;)");

    public static String escapeHtml(String input) {
        return input.replaceAll("&", "&amp;").replaceAll("<", "&lt;").replaceAll(">", "&gt;");
    }

    public static String formatMessage(String msg) {
        msg = escapeHtml(msg);

        // --
        // &mdash;
        msg = msg.replaceAll("((?<=\\s)|(?<=\\A))\\-\\-?((?=\\s)|(?=\\Z))", "$1&mdash;$2");

        // http://juick.com/last?page=2
        // <a href="http://juick.com/last?page=2" rel="nofollow">juick.com</a>
        msg = msg.replaceAll("((?<=\\s)|(?<=\\A))((?:ht|f)tps?://(?:www\\.)?([^\\/\\s\\n\\\"]+)/?[^\\s\\n\\\"]*)", "$1<a href=\"$2\" rel=\"nofollow\">$3</a>");

        // #12345
        // <a href="http://juick.com/12345">#12345</a>
        msg = msg.replaceAll("((?<=\\s)|(?<=\\A)|(?<=\\p{Punct}))#(\\d+)((?=\\s)|(?=\\Z)|(?=\\))|(?=\\.)|(?=\\,))", "$1<a href=\"http://juick.com/$2\">#$2</a>$3");

        // #12345/65
        // <a href="http://juick.com/12345#65">#12345/65</a>
        msg = msg.replaceAll("((?<=\\s)|(?<=\\A)|(?<=\\p{Punct}))#(\\d+)/(\\d+)((?=\\s)|(?=\\Z)|(?=\\p{Punct}))", "$1<a href=\"http://juick.com/$2#$3\">#$2/$3</a>$4");

        // *bold*
        // <b>bold</b>
        msg = msg.replaceAll("((?<=\\s)|(?<=\\A)|(?<=\\p{Punct}))\\*([^\\*\\n<>]+)\\*((?=\\s)|(?=\\Z)|(?=\\p{Punct}))", "$1<b>$2</b>$3");

        // /italic/
        // <i>italic</i>
        msg = msg.replaceAll("((?<=\\s)|(?<=\\A))/([^\\/\\n<>]+)/((?=\\s)|(?=\\Z)|(?=\\p{Punct}))", "$1<i>$2</i>$3");

        // _underline_
        // <span class="u">underline</span>
        msg = msg.replaceAll("((?<=\\s)|(?<=\\A))_([^\\_\\n<>]+)_((?=\\s)|(?=\\Z)|(?=\\p{Punct}))", "$1<span class=\"u\">$2</span>$3");

        // /12
        // <a href="#12">/12</a>
        msg = msg.replaceAll("((?<=\\s)|(?<=\\A))\\/(\\d+)((?=\\s)|(?=\\Z)|(?=\\p{Punct}))", "$1<a href=\"#$2\">/$2</a>$3");

        // @username@jabber.org
        // <a href="http://juick.com/username@jabber.org/">@username@jabber.org</a>
        msg = msg.replaceAll("((?<=\\s)|(?<=\\A))@([\\w\\-\\.]+@[\\w\\-\\.]+)((?=\\s)|(?=\\Z)|(?=\\p{Punct}))", "$1<a href=\"http://juick.com/$2/\">@$2</a>$3");

        // @username
        // <a href="http://juick.com/username/">@username</a>
        msg = msg.replaceAll("((?<=\\s)|(?<=\\A))@([\\w\\-]{2,16})((?=\\s)|(?=\\Z)|(?=\\p{Punct}))", "$1<a href=\"http://juick.com/$2/\">@$2</a>$3");

        // (http://juick.com/last?page=2)
        // (<a href="http://juick.com/last?page=2" rel="nofollow">juick.com</a>)
        Matcher m = regexLinks2.matcher(msg);
        StringBuffer sb = new StringBuffer();
        while (m.find()) {
            String url = m.group(3).replace(" ", "%20").replaceAll("\\s+", "");
            m.appendReplacement(sb, "$1$2<a href=\"" + url + "\" rel=\"nofollow\">$4</a>$5");
        }
        m.appendTail(sb);
        msg = sb.toString();

        // > citate
        msg = msg.replaceAll("(?:(?<=\\n)|(?<=\\A))&gt; *(.*)?(\\n|(?=\\Z))", "<blockquote>$1</blockquote>");
        msg = msg.replaceAll("</blockquote><blockquote>", "\n");

        msg = msg.replaceAll("\n", "<br/>\n");
        return msg;
    }
}