content: /*
   * Copyright 2024-2025 the original author or authors.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     https://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.alibaba.cloud.ai.a2a.registry.nacos.discovery;
  
  import java.util.List;
  import java.util.concurrent.ThreadLocalRandom;
  import java.util.concurrent.atomic.AtomicInteger;
  
  import com.alibaba.cloud.ai.graph.agent.a2a.AgentCardWrapper;
  import com.alibaba.nacos.common.utils.CollectionUtils;
  import io.a2a.spec.AgentCard;
  import io.a2a.spec.AgentInterface;
  
  /**
   * Spring AI Alibaba Agent Card Wrapper for Nacos.
   *
   * @author xiweng.yy
   */
  public class NacosAgentCardWrapper extends AgentCardWrapper {
  
  	private final AtomicInteger pollingIndex;
  
  	public NacosAgentCardWrapper(AgentCard agentCard) {
  		super(agentCard);
  		this.pollingIndex = new AtomicInteger(0);
  		shuffleStartIndex();
  	}
  
  	private void shuffleStartIndex() {
  		if (CollectionUtils.isNotEmpty(getAgentCard().additionalInterfaces())) {
  			int shuffleIndex = ThreadLocalRandom.current().nextInt(getAgentCard().additionalInterfaces().size());
  			pollingIndex.set(shuffleIndex);
  		}
  	}
  
  	@Override
  	public String url() {
  		if (CollectionUtils.isEmpty(getAgentCard().additionalInterfaces())) {
  			return super.url();
  		}
  		List<AgentInterface> agentInterfaces = getAgentCard().additionalInterfaces().stream().filter(agentInterface -> getAgentCard().preferredTransport().equals(agentInterface.transport())).toList();
  		if (CollectionUtils.isEmpty(agentInterfaces)) {
  			return super.url();
  		}
  		if (1 == agentInterfaces.size()) {
  			return agentInterfaces.get(0).url();
  		}
  		int index = pollingIndex.incrementAndGet() % agentInterfaces.size();
  		return agentInterfaces.get(index).url();
  	}
  
  	@Override
  	public void setAgentCard(AgentCard agentCard) {
  		super.setAgentCard(agentCard);
  		shuffleStartIndex();
  	}
  }
  