/*
 *  Copyright 2019-2020 Zheng Jie
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package me.zhengjie.utils;

import cn.hutool.core.io.resource.ClassPathResource;
import eu.bitwalker.useragentutils.Browser;
import eu.bitwalker.useragentutils.UserAgent;
import org.lionsoul.ip2region.DataBlock;
import org.lionsoul.ip2region.DbConfig;
import org.lionsoul.ip2region.DbSearcher;
import javax.servlet.http.HttpServletRequest;
import java.io.File;
import java.io.IOException;
import java.lang.reflect.Method;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Calendar;
import java.util.Date;

/**
 * @author Zheng Jie
 * 字符串工具类, 继承org.apache.commons.lang3.StringUtils类
 */
public class StringUtils extends org.apache.commons.lang3.StringUtils {

    private static final char SEPARATOR = '_';

    private static final String UNKNOWN = "unknown";

    /**
     * 驼峰命名法工具
     *
     * @return toCamelCase(" hello_world ") == "helloWorld"
     * toCapitalizeCamelCase("hello_world") == "HelloWorld"
     * toUnderScoreCase("helloWorld") = "hello_world"
     */
    public static String toCamelCase(String s) {
        if (s == null) {
            return null;
        }

        s = s.toLowerCase();

        StringBuilder sb = new StringBuilder(s.length());
        boolean upperCase = false;
        for (int i = 0; i < s.length(); i++) {
            char c = s.charAt(i);

            if (c == SEPARATOR) {
                upperCase = true;
            } else if (upperCase) {
                sb.append(Character.toUpperCase(c));
                upperCase = false;
            } else {
                sb.append(c);
            }
        }

        return sb.toString();
    }

    /**
     * 驼峰命名法工具
     *
     * @return toCamelCase(" hello_world ") == "helloWorld"
     * toCapitalizeCamelCase("hello_world") == "HelloWorld"
     * toUnderScoreCase("helloWorld") = "hello_world"
     */
    public static String toCapitalizeCamelCase(String s) {
        if (s == null) {
            return null;
        }
        s = toCamelCase(s);
        return s.substring(0, 1).toUpperCase() + s.substring(1);
    }

    /**
     * 驼峰命名法工具
     *
     * @return toCamelCase(" hello_world ") == "helloWorld"
     * toCapitalizeCamelCase("hello_world") == "HelloWorld"
     * toUnderScoreCase("helloWorld") = "hello_world"
     */
    static String toUnderScoreCase(String s) {
        if (s == null) {
            return null;
        }

        StringBuilder sb = new StringBuilder();
        boolean upperCase = false;
        for (int i = 0; i < s.length(); i++) {
            char c = s.charAt(i);

            boolean nextUpperCase = true;

            if (i < (s.length() - 1)) {
                nextUpperCase = Character.isUpperCase(s.charAt(i + 1));
            }

            if ((i > 0) && Character.isUpperCase(c)) {
                if (!upperCase || !nextUpperCase) {
                    sb.append(SEPARATOR);
                }
                upperCase = true;
            } else {
                upperCase = false;
            }

            sb.append(Character.toLowerCase(c));
        }

        return sb.toString();
    }

    /**
     * 获取ip地址
     */
    public static String getIp(HttpServletRequest request) {
        String ip = request.getHeader("x-forwarded-for");
        if (ip == null || ip.length() == 0 || UNKNOWN.equalsIgnoreCase(ip)) {
            ip = request.getHeader("Proxy-Client-IP");
        }
        if (ip == null || ip.length() == 0 || UNKNOWN.equalsIgnoreCase(ip)) {
            ip = request.getHeader("WL-Proxy-Client-IP");
        }
        if (ip == null || ip.length() == 0 || UNKNOWN.equalsIgnoreCase(ip)) {
            ip = request.getRemoteAddr();
        }
        String comma = ",";
        String localhost = "127.0.0.1";
        if (ip.contains(comma)) {
            ip = ip.split(",")[0];
        }
        if  (localhost.equals(ip))  {
            // 获取本机真正的ip地址
            try {
                ip = InetAddress.getLocalHost().getHostAddress();
            } catch (UnknownHostException e) {
                e.printStackTrace();
            }
        }
        return ip;
    }

    /**
     * 根据ip获取详细地址
     */
    public static String getCityInfo(String ip) {
        DbSearcher searcher = null;
        try {
            String path = "ip2region/ip2region.db";
            String name = "ip2region.db";
            DbConfig config = new DbConfig();
            File file = FileUtil.inputStreamToFile(new ClassPathResource(path).getStream(), name);
            searcher = new DbSearcher(config, file.getPath());
            Method method;
            method = searcher.getClass().getMethod("btreeSearch", String.class);
            DataBlock dataBlock;
            dataBlock = (DataBlock) method.invoke(searcher, ip);
            String address = dataBlock.getRegion().replace("0|","");
            char symbol = '|';
            if(address.charAt(address.length()-1) == symbol){
                address = address.substring(0,address.length() - 1);
            }
            return address.equals(ElAdminConstant.REGION)?"内网IP":address;
        } catch (Exception e) {
            e.printStackTrace();
        }finally {
            if(searcher!=null){
                try {
                    searcher.close();
                } catch (IOException ignored) {
                }
            }

        }
        return "";
    }

    public static String getBrowser(HttpServletRequest request){
        UserAgent userAgent = UserAgent.parseUserAgentString(request.getHeader("User-Agent"));
        Browser browser = userAgent.getBrowser();
        return browser.getName();
    }

    /**
     * 获得当天是周几
     */
    public static String getWeekDay(){
        String[] weekDays = {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"};
        Calendar cal = Calendar.getInstance();
        cal.setTime(new Date());

        int w = cal.get(Calendar.DAY_OF_WEEK) - 1;
        if (w < 0){
            w = 0;
        }
        return weekDays[w];
    }

    /**
     * 获取当前机器的IP
     * @return /
     */
    public static String getLocalIp(){
        InetAddress addr;
        try {
            addr = InetAddress.getLocalHost();
        } catch (UnknownHostException e) {
            return "unknown";
        }
        byte[] ipAddr = addr.getAddress();
        StringBuilder ipAddrStr = new StringBuilder();
        for (int i = 0; i < ipAddr.length; i++) {
            if (i > 0) {
                ipAddrStr.append(".");
            }
            ipAddrStr.append(ipAddr[i] & 0xFF);
        }
        return ipAddrStr.toString();
    }
}
