package com.fd.shiro;

import com.fd.entity.User;
import com.fd.repository.UserRepository;
import lombok.extern.log4j.Log4j2;
import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.AuthenticationInfo;
import org.apache.shiro.authc.AuthenticationToken;
import org.apache.shiro.authc.SimpleAuthenticationInfo;
import org.apache.shiro.authz.AuthorizationInfo;
import org.apache.shiro.authz.SimpleAuthorizationInfo;
import org.apache.shiro.realm.AuthorizingRealm;
import org.apache.shiro.subject.PrincipalCollection;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Service;

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;

/**
 * 配置不校验的话，是不会走这个方法的
 */
@Log4j2
@Service
public class MyRealm extends AuthorizingRealm {


    @Autowired
    private UserRepository userRepository;

    @Autowired
    private RedisTemplate redisTemplate;



    /**
     * 大坑！，必须重写此方法，不然Shiro会报错
     */
    @Override
    public boolean supports(AuthenticationToken token) {
        return token instanceof JWTToken;
    }

    /**
     * 只有当需要检测用户权限的时候才会调用此方法，例如checkRole,checkPermission之类的
     *
     * principals： 是token
     */
    @Override
    protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principals) {
        String username = JWTUtil.getUsername(principals.toString());
        User user = userRepository.findByUsername(username);
        SimpleAuthorizationInfo simpleAuthorizationInfo = new SimpleAuthorizationInfo();
        simpleAuthorizationInfo.addRole(user.getRole());

        // db 添加权限时，用“，”隔开
        Set<String> permission = new HashSet<>(Arrays.asList(user.getPermission().split(",")));
        simpleAuthorizationInfo.addStringPermissions(permission);

        return simpleAuthorizationInfo;
    }

    /**
     * 默认使用此方法进行用户名正确与否验证，错误抛出异常即可。
     */
    @Override
    protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken auth) throws AuthenticationException {
//        log.warn("run doGetAuthenticationInfo");
        String token = (String) auth.getCredentials();
//        log.warn("token: {}", token);
        // 解密获得username，用于和数据库进行对比
        String username = JWTUtil.getUsername(token);
        if (username == null) {
            log.info("error token username");
            throw new AuthenticationException("token invalid");
        }

        User user = userRepository.findByUsername(username);
        if (user == null) {
            log.info("error token user");
            throw new AuthenticationException("User didn't existed!");
        }

        // 校验请求token是否跟redis token一致
        String redisToken = (String) redisTemplate.opsForValue().get(user.getUsername());
        if (!token.equals(redisToken)) {
            log.info("error token redis");
            throw new AuthenticationException("token invalid");
        }


        if (! JWTUtil.verify(token, username, user.getPassword())) {
            log.info("error token username or password");
            throw new AuthenticationException("token invalid");
        }

//        log.warn("end doGetAuthenticationInfo");

        return new SimpleAuthenticationInfo(token, token, "my_realm");
    }
}