/*
 * Juick
 * Copyright (C) 2008-2011, 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.www;

import com.juick.Tag;
import com.juick.User;
import com.juick.server.TagQueries;
import com.mitchellbosecke.pebble.PebbleEngine;
import org.apache.commons.codec.digest.DigestUtils;
import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.jdbc.core.JdbcTemplate;

import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.Part;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.net.URL;
import java.net.URLConnection;
import java.nio.charset.StandardCharsets;
import java.nio.file.Paths;
import java.util.*;

/**
 *
 * @author Ugnich Anton
 */
public class Utils {

    private static final Logger logger = LoggerFactory.getLogger(Utils.class);

    private static final PebbleEngine engine = new PebbleEngine.Builder().build();
    private static String tmpDir = "/var/www/juick.com/i/tmp/";

    public static String getCookie(HttpServletRequest request, String name) {
        Cookie cookies[] = request.getCookies();
        if (cookies != null) {
            return Arrays.stream(cookies).filter(c ->
                    c.getName().equals(name)).findAny().map(Cookie::getValue).orElse(null);
        }
        return null;
    }

    public static String receiveMultiPartFile(Part filePart) throws IOException, ServletException {
        String attachmentFName = null;

        if (filePart != null) {
            String partname = Utils.getPartFilename(filePart);
            if (partname != null && partname.length() > 0) {
                String attachmentType = partname.substring(partname.length() - 3).toLowerCase();
                if (attachmentType.equals("jpg") || attachmentType.equals("peg") || attachmentType.equals("png")) {
                    if (attachmentType.equals("peg")) {
                        attachmentType = "jpg";
                    }
                    attachmentFName = DigestUtils.md5Hex(UUID.randomUUID().toString()) + "." + attachmentType;
                    filePart.write(Paths.get(getTmpDir(), attachmentFName).toString());
                } else {
                    throw new IOException("Wrong file type");
                }
            }
        }

        return attachmentFName;
    }

    public static com.juick.User getVisitorUser(JdbcTemplate sql, HttpServletRequest request, HttpServletResponse response) {
        String hash = getCookie(request, "hash");
        if (hash != null) {
            com.juick.User visitor = com.juick.server.UserQueries.getUserByHash(sql, hash);
            if (response != null && visitor.getUid() > 0) {
                response.setHeader("X-Username", visitor.getName());
            }
            return visitor;
        } else {
            return new User();
        }
    }

    public static void sendTemporaryRedirect(HttpServletResponse response, String location) {
        response.setStatus(HttpServletResponse.SC_MOVED_TEMPORARILY);
        response.setHeader("Location", location);
    }

    public static void sendPermanentRedirect(HttpServletResponse response, String location) {
        response.setStatus(HttpServletResponse.SC_MOVED_PERMANENTLY);
        response.setHeader("Location", location);
    }

    public static String getPartFilename(Part part) {
        for (String cd : part.getHeader("content-disposition").split(";")) {
            if (cd.trim().startsWith("filename")) {
                String filename = cd.substring(cd.indexOf('=') + 1).trim().replace("\"", "");
                return filename.substring(filename.lastIndexOf('/') + 1).substring(filename.lastIndexOf('\\') + 1); // MSIE fix.
            }
        }
        return null;
    }

    public static void replyJSON(HttpServletRequest request, HttpServletResponse response, String json) throws IOException {
        response.setContentType("application/json; charset=UTF-8");
        response.setHeader("Access-Control-Allow-Origin", "*");

        String callback = request.getParameter("callback");
        if (callback != null && (callback.length() > 64 || !callback.matches("[a-zA-Z0-9\\-\\_]+"))) {
            callback = null;
        }

        PrintWriter out = response.getWriter();
        try {
            if (callback != null) {
                out.print(callback + "(");
                out.print(json);
                out.print(")");
            } else {
                out.print(json);
            }
        } finally {
            out.close();
        }
    }

    public static String encodeSphinx(String str) {
        return str.replaceAll("@", "\\\\@");
    }

    public static String fetchURL(String url) {
        try {
            URLConnection c = new URL(url).openConnection();
            return IOUtils.toString(c.getInputStream(), StandardCharsets.UTF_8);
        } catch (IOException e) {
            logger.warn("fetchURL", e);
            return null;
        }
    }

    public static String downloadImage(URL url) throws Exception {
        String attachmentFName = null;
        Exception ex = null;

        InputStream is = null;
        FileOutputStream fos = null;
        try {
            URLConnection urlConn = url.openConnection();
            is = urlConn.getInputStream();
            String mime = urlConn.getContentType();

            String attachmentType;
            if (mime != null && mime.equals("image/jpeg")) {
                attachmentType = "jpg";
            } else if (mime != null && mime.equals("image/png")) {
                attachmentType = "png";
            } else {
                throw new Exception("Wrong file type");
            }

            attachmentFName = DigestUtils.md5Hex(UUID.randomUUID().toString()) + "." + attachmentType;
            fos = new FileOutputStream("/var/www/juick.com/i/tmp/" + attachmentFName);
            byte[] buffer = new byte[10240];
            int len;
            while ((len = is.read(buffer)) > 0) {
                fos.write(buffer, 0, len);
            }
        } catch (Exception e) {
            ex = e;
            attachmentFName = null;
        } finally {
            try {
                if (is != null) {
                    is.close();
                }
            } finally {
                if (fos != null) {
                    fos.close();
                }
            }
        }

        if (ex != null) {
            throw ex;
        } else {
            return attachmentFName;
        }
    }

    public static List<Tag> parseTags(JdbcTemplate sql, String tagsStr) {
        List<com.juick.Tag> tags = new ArrayList<>();
        String tagsArr[];
        if (tagsStr != null && !tagsStr.isEmpty()) {
            tagsArr = tagsStr.split("[ \\,]");
            for (int i = 0; i < tagsArr.length; i++) {
                if (tagsArr[i].startsWith("*")) {
                    tagsArr[i] = tagsArr[i].substring(1);
                }
                if (tagsArr[i].length() > 64) {
                    tagsArr[i] = tagsArr[i].substring(0, 64);
                }
            }
            tags = TagQueries.getTags(sql, tagsArr, true);
            while (tags.size() > 5) {
                tags.remove(5);
            }
        }
        return tags;
    }

    public static String receiveAttachment(Part part, String paramImg) throws Exception {
        String attachmentFName = receiveMultiPartFile(part);

        if (attachmentFName == null && paramImg != null && paramImg.length() > 10) {
            URL imgUrl = new URL(paramImg);
            attachmentFName = downloadImage(imgUrl);
        }
        return attachmentFName;
    }

    public static PebbleEngine getEngine() {
        return engine;
    }

    public static String getTmpDir() {
        return tmpDir;
    }

    public static void setTmpDir(String tmpDir) {
        Utils.tmpDir = tmpDir;
    }
}