package com.newfiber.gateway.filter;

import com.newfiber.common.core.utils.ServletUtils;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Pattern;
import org.springframework.cloud.gateway.filter.GatewayFilter;
import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
import org.springframework.stereotype.Component;

/**
 * 黑名单过滤器
 * 
 * @author newfiber
 */
@Component
public class BlackListUrlFilter extends AbstractGatewayFilterFactory<BlackListUrlFilter.Config>{
    @Override
    public GatewayFilter apply(Config config){
        return (exchange, chain) -> {

            String url = exchange.getRequest().getURI().getPath();
            if (config.matchBlacklist(url)){
                return ServletUtils.webFluxResponseWriter(exchange.getResponse(), "请求地址不允许访问");
            }

            return chain.filter(exchange);
        };
    }

    public BlackListUrlFilter(){
        super(Config.class);
    }

    public static class Config{
        private List<String> blacklistUrl;

        private List<Pattern> blacklistUrlPattern = new ArrayList<>();

        public boolean matchBlacklist(String url){
            return !blacklistUrlPattern.isEmpty() && blacklistUrlPattern.stream().anyMatch(p -> p.matcher(url).find());
        }

        public List<String> getBlacklistUrl(){
            return blacklistUrl;
        }

        public void setBlacklistUrl(List<String> blacklistUrl){
            this.blacklistUrl = blacklistUrl;
            this.blacklistUrlPattern.clear();
            this.blacklistUrl.forEach(url -> {
                this.blacklistUrlPattern.add(Pattern.compile(url.replaceAll("\\*\\*", "(.*?)"), Pattern.CASE_INSENSITIVE));
            });
        }
    }

}