package com.szwl;

import org.apache.commons.lang.StringUtils;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.web.cors.reactive.CorsUtils;
import org.springframework.web.server.ServerWebExchange;
import org.springframework.web.server.WebFilter;
import org.springframework.web.server.WebFilterChain;
import reactor.core.publisher.Mono;

@Configuration
@EnableAutoConfiguration  //启用自动配置 该框架就能够进行行为的配置，以引导应用程序的启动与运行, 根据导入的starter-pom 自动加载配置
@ComponentScan
public class GatewayServerApplication {

	public static void main(String[] args) {
		SpringApplication.run(GatewayServerApplication.class, args);
	}

	private static final String ALL = "*";

	private static final String MAX_AGE = "18000L";
	@Bean
	public WebFilter corsFilter() {
		return (ServerWebExchange ctx, WebFilterChain chain) -> {
			ServerHttpRequest request = ctx.getRequest();

			if (!CorsUtils.isCorsRequest(request)) {
				return chain.filter(ctx);
			}
			HttpHeaders requestHeaders = request.getHeaders();

			ServerHttpResponse response = ctx.getResponse();

			HttpMethod requestMethod = requestHeaders.getAccessControlRequestMethod();

			HttpHeaders headers = response.getHeaders();
			headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_ORIGIN, ALL);
//			headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_ORIGIN, requestHeaders.getOrigin());

			String requestHeadersAllowHeaders = StringUtils.strip(String.valueOf(requestHeaders.get("Access-Control-Request-Headers")), "[]");
//            log.info("HttpHeaders:",requestHeadersAllowHeaders);

			headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_HEADERS, requestHeadersAllowHeaders);
//			headers.addAll(HttpHeaders.ACCESS_CONTROL_ALLOW_HEADERS, requestHeaders.getAccessControlRequestHeaders());

//			headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_METHODS, ALL);
			if (requestMethod != null) {
				headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_METHODS, requestMethod.name());
			}
			headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_CREDENTIALS, "true");
			headers.add(HttpHeaders.ACCESS_CONTROL_EXPOSE_HEADERS, ALL);
			headers.add(HttpHeaders.ACCESS_CONTROL_MAX_AGE, MAX_AGE);

			HttpMethod requestMethod2 = request.getMethod();
			if (request.getMethod() == HttpMethod.OPTIONS) {
				response.setStatusCode(HttpStatus.OK);
				return Mono.empty();
			}

			return chain.filter(ctx);
		};
	}

	


}