/*
 * Copyright (C) 2008-2017, 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.rss;

import com.juick.Message;
import com.juick.Tag;
import com.juick.util.DateFormattersHolder;
import com.juick.util.MessageUtils;
import org.apache.commons.codec.CharEncoding;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.math.NumberUtils;
import org.apache.commons.text.StringEscapeUtils;
import org.springframework.jdbc.core.JdbcTemplate;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Collections;
import java.util.Date;
import java.util.List;

/**
 * @author ugnich
 */
public class LegacyRSS {

    JdbcTemplate sql;

    public LegacyRSS(JdbcTemplate sql) {
        this.sql = sql;
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        if (request.getCharacterEncoding() == null) {
            request.setCharacterEncoding(CharEncoding.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 = Collections.emptyList(); //MessagesQueries.getMessages(sql, mids);
                responseMessages(response, 0, null, msgs);
            } else {
                response.sendError(HttpServletResponse.SC_NOT_FOUND);
            }
        } else if (uri.equals("/comments")) {
            int hours = NumberUtils.toInt(request.getParameter("hours"), 0);
            if (hours > 0 && hours < 13) {
                responseReplies(response, hours);
            } else {
                response.sendError(HttpServletResponse.SC_NOT_FOUND);
            }
        } else if (uri.matches("^/[a-zA-Z0-9\\-]{2,16}/blog$")) {
            String uname = uri.substring(1, uri.length() - 5);
            int uid = 0; // UserQueries.getUIDbyName(sql, uname);
            if (uid > 0) {
                List<Integer> mids = Collections.emptyList(); //MessagesQueries.getUserBlog(sql, uid, 0, 0);
                if (!mids.isEmpty()) {
                    List<Message> msgs = Collections.emptyList();// MessagesQueries.getMessages(sql, mids);
                    responseMessages(response, uid, uname, msgs);
                } else {
                    response.sendError(HttpServletResponse.SC_NOT_FOUND);
                }
            } else {
                response.sendError(HttpServletResponse.SC_NOT_FOUND);
            }
        } else {
            response.sendError(HttpServletResponse.SC_NOT_FOUND);
        }
    }

    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 (Tag tag : msg.getTags()) {
                        out.print(" *" + tag);
                    }
                }
                out.println("]]></title>");
                out.println("<description><![CDATA[" + MessageUtils.formatMessage(StringUtils.defaultString(msg.getText())) + "]]></description>");

                out.println("<pubDate>" + DateFormattersHolder.getRssFormatterInstance().format(msg.getTimestamp()) + "</pubDate>");

                out.println("<comments>http://juick.com/" + msg.getUser().getName() + "/" + msg.getMid() + "</comments>");
                if (!msg.getTags().isEmpty()) {
                    for (Tag tag : msg.getTags()) {
                        out.println("<category>" + StringEscapeUtils.escapeHtml4(tag.getName()) + "</category>");
                    }
                }
                if (msg.getAttachmentType() != null) {
                    if (msg.getAttachmentType().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.getAttachmentType().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).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[" + MessageUtils.formatMessage(r.description) + "]]></description>");
                out.println("<pubDate>" + DateFormattersHolder.getRssFormatterInstance().format(r.pubDate.toInstant()) + "</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);
    }
}