package com.xiaopeng.gateway.filter;

import com.alibaba.fastjson2.JSON;
import com.alibaba.fastjson2.JSONObject;
import com.xiaopeng.common.core.exception.auth.NotLoginException;
import com.xiaopeng.gateway.config.properties.AntiShakeProperties;
import org.apache.commons.lang3.RandomStringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import com.xiaopeng.common.core.constant.CacheConstants;
import com.xiaopeng.common.core.constant.HttpStatus;
import com.xiaopeng.common.core.constant.SecurityConstants;
import com.xiaopeng.common.core.constant.TokenConstants;
import com.xiaopeng.common.core.utils.JwtUtils;
import com.xiaopeng.common.core.utils.ServletUtils;
import com.xiaopeng.common.core.utils.StringUtils;
import com.xiaopeng.common.redis.service.RedisService;
import com.xiaopeng.gateway.config.properties.IgnoreWhiteProperties;
import io.jsonwebtoken.Claims;
import reactor.core.publisher.Mono;

import java.util.HashMap;
import java.util.Map;
import java.util.UUID;


/**
 * 网关鉴权
 *
 * @author ruoyi
 */
@Component
public class AuthFilter implements GlobalFilter, Ordered {
	private static final Logger log = LoggerFactory.getLogger(AuthFilter.class);
	
	// 排除过滤的 uri 地址，nacos自行添加
	@Autowired
	private IgnoreWhiteProperties ignoreWhite;
	@Autowired
	private AntiShakeProperties antiShakeProperties;

	@Autowired
	private RedisService redisService;

    @Value("${xiaopeng.xtiger.sso.issuer}")
    private String issuer;

    @Value("${xiaopeng.xtiger.sso.appId}")
    private String appId;

    @Value("${xiaopeng.xtiger.sso.serverHost}")
    private String serverHost;
	
	
	
	
	@Override
	public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
		ServerHttpRequest request = exchange.getRequest();
		ServerHttpRequest.Builder mutate = request.mutate();
		
		String url = request.getURI().getPath();
		// 跳过不需要验证的路径
		if (StringUtils.matches(url, ignoreWhite.getWhites())) {
			return chain.filter(exchange);
		}
		//校验账户是否有效
		try {
			verifyToken(request);
		}catch (Exception e){
			return unauthorizedResponse(exchange, e.getMessage());
		}


		String token = getToken(request);
		Claims claims = JwtUtils.parseToken(token);
		String userkey = JwtUtils.getUserKey(claims);
		String userid = JwtUtils.getUserId(claims);
		String username = JwtUtils.getUserName(claims);
		String userType = JwtUtils.getUserType(claims);
		String operationUserKey = JwtUtils.getOperationUserKey(claims);
		if (!checkPathPermission(userType, url)) {
			return unauthorizedResponse(exchange, "无权访问当前资源");
		}
		String redisKey = "";
		if ("system".equals(userType)) {
			redisKey = StringUtils.isNotBlank(userkey) ? getTokenKey(userkey) : "";
		}
		if ("operation".equals(userType)) {
			redisKey = StringUtils.isNotBlank(operationUserKey) ? getTokenKey(operationUserKey) : "";
		}
		if (StringUtils.isBlank(redisKey)) {
			return unauthorizedResponse(exchange, "登录状态已过期");
		}

		boolean islogin = redisService.hasKey(redisKey);
		if (!islogin)
		{
			return unauthorizedResponse(exchange, "登录状态已过期");
		}
		// 设置用户信息到请求
		addHeader(mutate, SecurityConstants.USER_KEY, userkey);
		addHeader(mutate, SecurityConstants.DETAILS_USER_ID, userid);
		addHeader(mutate, SecurityConstants.DETAILS_USERNAME, username);
		addHeader(mutate, SecurityConstants.USER_TYPE, userType);
		addHeader(mutate, SecurityConstants.OPERATION_USER_KEY, operationUserKey);
		// 内部请求来源参数清除
		removeHeader(mutate, SecurityConstants.FROM_SOURCE);
		return chain.filter(exchange.mutate().request(mutate.build()).build());
	}
	
	private void addHeader(ServerHttpRequest.Builder mutate, String name, Object value) {
		if (value == null) {
			return;
		}
		String valueStr = value.toString();
		String valueEncode = ServletUtils.urlEncode(valueStr);
		mutate.header(name, valueEncode);
	}
	
	private void removeHeader(ServerHttpRequest.Builder mutate, String name) {
		mutate.headers(httpHeaders -> httpHeaders.remove(name)).build();
	}
	
	private Mono<Void> unauthorizedResponse(ServerWebExchange exchange, String msg) {
		log.error("[鉴权异常处理]请求路径:{}", exchange.getRequest().getPath() + "\n" + msg);
        String s = UUID.randomUUID().toString();
        String state1 = s.substring(0, 8) + s.substring(9, 13) + s.substring(14, 18) + s.substring(19, 23) + s.substring(24);
        String s1 = UUID.randomUUID().toString();
        String state2 = s1.substring(0, 8) + s.substring(9, 13) + s.substring(14, 18) + s.substring(19, 23) + s.substring(24);
        String nonce = RandomStringUtils.randomAlphanumeric(6);
        JSONObject jsonObject = JSON.parseObject("{\n" +
                "    \"uid\": null,\n" +
                "    \"username\": null,\n" +
                "    \"authUrl\": \"" + issuer + "/oidc/auth?scope=openid+profile+offline_access+phone+email&response_type=code&redirect_uri=" + serverHost + "/dashboard&state=" + state1 + "&nonce=" + nonce + "&client_id=" + appId + "\",\n" +
                "    \"logoutUrl\": null,\n" +
                "    \"callbackUrl\": \"" + serverHost + "/dashboard?state=" + state2 + "\"\n" +
                "  }");
		return ServletUtils.webFluxResponseWriter(exchange.getResponse(), jsonObject.toString(), HttpStatus.UNAUTHORIZED);
	}
	
	
	/**
	 * 获取缓存key
	 */
	private String getTokenKey(String token) {
		return CacheConstants.LOGIN_TOKEN_KEY + token;
	}

	private boolean checkPathPermission(String userType, String url) {
		boolean appPath = StringUtils.isNotBlank(url) && url.contains("/maintenance-app");
		if ("operation".equals(userType)) {
			return appPath;
		}
		if ("system".equals(userType)) {
			return !appPath;
		}
		return true;
	}
	
	/**
	 * 获取请求token
	 */
	private String getToken(ServerHttpRequest request) {
		String token = request.getHeaders().getFirst(TokenConstants.AUTHENTICATION);
		// 如果前端设置了令牌前缀，则裁剪掉前缀
		if (StringUtils.isNotEmpty(token) && token.startsWith(TokenConstants.PREFIX)) {
			token = token.replaceFirst(TokenConstants.PREFIX, StringUtils.EMPTY);
		}
		return token;
	}

	
	
	
	/**
	 * 验证token
	 * @param request
	 * @throws Exception
	 */
	public void verifyToken(ServerHttpRequest request) throws Exception{
		String token = getToken(request);
		if (StringUtils.isEmpty(token)) {
			throw new NotLoginException("令牌不能为空");
		}
		Claims claims = JwtUtils.parseToken(token);
		if (claims == null) {
			throw new NotLoginException("令牌已过期或验证不正确！");
		}
		String userid = JwtUtils.getUserId(claims);
		if (StringUtils.isEmpty(userid)) {
			throw new NotLoginException("令牌验证失败");
		}
	}
	
	
	@Override
	public int getOrder() {
		return -300;
	}
}