package com.dsh.utils;

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class EmojiUtil {
    /**
     * @param str 待转换字符串
     * @return 转换后字符串
     * @throws UnsupportedEncodingException exception
     * @Description 将字符串中的emoji表情转换成可以在utf-8字符集数据库中保存的格式（表情占4个字节，需要utf8mb4字符集）
     */
    public static String emojiEncode(String str)
            throws UnsupportedEncodingException {
        String patternString = "([\\x{10000}-\\x{10ffff}\ud800-\udfff])";

        Pattern pattern = Pattern.compile(patternString);
        Matcher matcher = pattern.matcher(str);
        StringBuffer sb = new StringBuffer();
        while (matcher.find()) {
            try {
                matcher.appendReplacement(
                        sb,
                        "[["
                                + URLEncoder.encode(matcher.group(1),
                                "UTF-8") + "]]");
            } catch (UnsupportedEncodingException e) {
//                LOG.error("emojiConvert error", e);
                throw e;
            }
        }
        matcher.appendTail(sb);
//        LOG.debug("emojiConvert " + str + " to " + sb.toString()
//                + ", len：" + sb.length());
        return sb.toString();
    }

    /**
     * @param str 转换后的字符串
     * @return 转换前的字符串
     * @throws UnsupportedEncodingException exception
     * @Description 还原utf8数据库中保存的含转换后emoji表情的字符串
     */
    public static String emojiDecode(String str)
            throws UnsupportedEncodingException {
        String patternString = "\\[\\[(.*?)\\]\\]";

        Pattern pattern = Pattern.compile(patternString);
        if (str == null) {
            return str;
        }
        Matcher matcher = pattern.matcher(str);

        StringBuffer sb = new StringBuffer();
        while (matcher.find()) {
            try {
                matcher.appendReplacement(sb,
                        URLDecoder.decode(matcher.group(1), "UTF-8"));
            } catch (UnsupportedEncodingException e) {
//                LOG.error("emojiRecovery error", e);
                throw e;
            }
        }
        matcher.appendTail(sb);
//        LOG.debug("emojiRecovery " + str + " to " + sb.toString());
//        System.out.println("emojiRecovery " + str + " to " + sb.toString());
        return sb.toString();
    }

    /**
     * @param str 待过滤字符串
     * @return 过滤后字符串
     * exception
     * @Description 将字符串中的emoji表情过滤掉
     */
    public static String emojiSub(String str) {
        String patternString = "([\\x{10000}-\\x{10ffff}\ud800-\udfff])";
        Pattern pattern = Pattern.compile(patternString);
        Matcher matcher = pattern.matcher(str);
        StringBuffer sb = new StringBuffer();
        while (matcher.find()) {
            matcher.appendReplacement(sb, "");
        }
        matcher.appendTail(sb);
        return sb.toString();
    }

}