package com.moon.server.interceptor;

import com.moon.server.entity.all.ResAuthEntity;
import com.moon.server.entity.all.StaticData;
import com.moon.server.entity.sys.TokenEntity;
import com.moon.server.entity.sys.UserEntity;
import com.moon.server.helper.StringHelper;
import com.moon.server.helper.WebHelper;
import com.moon.server.service.all.PermsService;
import com.moon.server.service.all.SysService;
import com.moon.server.service.sys.ResLogService;

import javax.annotation.Resource;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.List;

/**
 * 代理过滤器
 * @author WWW
 * @date 2023-07-04
 */
@WebFilter(urlPatterns = {"/proxy/*"})
public class ProxyFilter implements Filter {
    @Resource
    private SysService sysService;

    @Resource
    private PermsService permsService;

    @Resource
    private ResLogService resLogService;

    private final static int LEN = "/proxy/".length();

    @Override
    public void init(FilterConfig filterConfig) {
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) {
        HttpServletRequest req = (HttpServletRequest) request;
        HttpServletResponse res = (HttpServletResponse) response;

        String token = getToken(req);
        if (!check(req, res, token)) {
            return;
        }

        String uri = req.getRequestURI();
        int resId = getResId(uri, LEN + token.length() + 1);

        //
        insertLog(req, res);
    }

    @Override
    public void destroy() {
    }

    /**
     * 获取令牌
     */
    private String getToken(HttpServletRequest req) {
        return req.getRequestURI().substring(LEN, req.getRequestURI().indexOf("/", LEN));
    }

    /**
     * 获取资源ID
     */
    private int getResId(String uri, int start) {
        int end = uri.indexOf("/", start);
        String str = -1 == end ? uri.substring(start) : uri.substring(start, end);

        return Integer.parseInt(str);
    }

    /**
     * 检查
     */
    private boolean check(HttpServletRequest req, HttpServletResponse res, String token) {
        // 3.获取用户
        UserEntity ue = sysService.tokenService.getUserByToken(token);
        if (ue == null) {
            return WebHelper.writeStr2Page(res, AuthInterceptor.NO_LOGIN);
        }

        // 4.获取IP
        String ip = WebHelper.getIpAddress(req);
        if (StringHelper.isEmpty(ip)) {
            return WebHelper.writeStr2Page(res, AuthInterceptor.IP_NULL);
        }

        // 5.检查黑名单
        if (!checkBlackList(ip, req)) {
            return WebHelper.writeStr2Page(res, AuthInterceptor.BLACK_LIST);
        }

        // 6.admin跳过权限检测
        if (StaticData.ADMIN.equals(ue.getUid())) {
            return true;
        }

        // 7.检查白名单
        if (!checkWhiteList(ip, req)) {
            // 检查IP一致性
            if (!checkIpSource(ip, token)) {
                return WebHelper.writeStr2Page(res, AuthInterceptor.ILLEGAL_TOKEN);
            }
        }

        // 8.检查用户ID是否禁用
        if (sysService.tokenService.isUidDisable(ue)) {
            return WebHelper.writeStr2Page(res, AuthInterceptor.USER_LOCK);
        }

        return true;
    }

    /**
     * 检查黑名单
     */
    private boolean checkBlackList(String ip, HttpServletRequest request) {
        List<String> blackList = sysService.blacklistService.selectIpList(1);
        if (blackList == null || blackList.isEmpty()) {
            return true;
        }
        if (blackList.contains(ip)) {
            return false;
        }

        return true;
    }

    /**
     * 检查白名单
     */
    private boolean checkWhiteList(String ip, HttpServletRequest request) {
        List<String> whiteList = sysService.blacklistService.selectIpList(2);
        if (whiteList == null || whiteList.isEmpty()) {
            return false;
        }

        return whiteList.contains(ip);
    }

    /**
     * 检查IP一致性
     */
    private boolean checkIpSource(String ip, String token) {
        TokenEntity te = sysService.tokenService.getEntityByToken(token);

        return te.getIp().equals(ip);
    }

    private boolean checkPerms(UserEntity ue, int resId){
        String uid = StaticData.ADMIN.equals(ue.getUid()) ? null : ue.getUid();
        List<ResAuthEntity> rs = permsService.selectRes(uid);

        return true;
    }

    /**
     * 插入日志
     */
    private void insertLog(HttpServletRequest req, HttpServletResponse res) {
        String ip = WebHelper.getIpAddress(req);
        //log.info("uriOri={} rAddr={} rHost={} token={}", uriOri, addr, host, token);
    }
}