package com.lf.server.interceptor;

import com.alibaba.fastjson.JSON;
import com.lf.server.entity.all.HttpStatus;
import com.lf.server.entity.all.ResponseMsg;
import com.lf.server.entity.all.StaticData;
import com.lf.server.entity.sys.UserEntity;
import com.lf.server.helper.StringHelper;
import com.lf.server.helper.WebHelper;
import com.lf.server.service.sys.TokenService;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * 身份认证拦截器
 * @author WWW
 */
@Configuration
public class AuthInterceptor implements HandlerInterceptor {
    private TokenService tokenService;

    private static final Log log = LogFactory.getLog(AuthInterceptor.class);

    private static final String NO_TOKEN = JSON.toJSONString(new ResponseMsg<String>(HttpStatus.TOKEN_ERROR, "找不到令牌"));

    private static final String NO_LOGIN = JSON.toJSONString(new ResponseMsg<String>(HttpStatus.NO_LOGIN_ERROR, "用户未登录"));

    public AuthInterceptor(TokenService tokenService) {
        this.tokenService = tokenService;
    }

    /**
     * Controller执行之前执行，如果返回值是true则代表放行，返回false则拦截
     *
     * @param request
     * @param response
     * @param handler
     * @return
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) {
        try {
            System.out.println(request.getRequestURI().toLowerCase() + "," + (handler instanceof HandlerMethod));

            // 非方法，无需拦截
            if (!(handler instanceof HandlerMethod)) {
                return true;
            }

            // 无需授权
            if (noNeedAuth(request)) {
                return true;
            }

            String token = WebHelper.getToken(request);
            if (StringHelper.isNull(token)) {
                WebHelper.write2Page(response, NO_TOKEN);
                return false;
            }

            UserEntity ue = tokenService.getCurrentUser(request);
            if (ue == null) {
                WebHelper.write2Page(response, NO_LOGIN);
                return false;
            }

            //noinspection AlibabaRemoveCommentedCode
            // 权限校验

            return true;
        } catch (Exception ex) {
            log.error(ex.getMessage() + ex.getStackTrace() + "\n");
            return false;
        }
    }

    /**
     * 无需授权
     *
     * @param request
     * @return
     */
    private static boolean noNeedAuth(HttpServletRequest request) {
        String uri = request.getRequestURI().toLowerCase();
        for (String page : StaticData.EXCLUDE_PATH) {
            if (uri.contains(page)) {
                return true;
            }
        }

        return false;
    }
}