/*
 * Copyright 1999-2018 Alibaba Group Holding Ltd.
 *
 * 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
 *
 *      http://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.nacos.config.server.controller;

import com.alibaba.nacos.api.config.remote.request.ClientConfigMetricRequest;
import com.alibaba.nacos.api.config.remote.response.ClientConfigMetricResponse;
import com.alibaba.nacos.api.exception.NacosException;
import com.alibaba.nacos.auth.annotation.Secured;
import com.alibaba.nacos.common.http.Callback;
import com.alibaba.nacos.common.http.HttpClientBeanHolder;
import com.alibaba.nacos.common.http.HttpUtils;
import com.alibaba.nacos.common.http.client.NacosAsyncRestTemplate;
import com.alibaba.nacos.common.http.param.Header;
import com.alibaba.nacos.common.http.param.Query;
import com.alibaba.nacos.common.model.RestResult;
import com.alibaba.nacos.common.utils.NamespaceUtil;
import com.alibaba.nacos.common.utils.StringUtils;
import com.alibaba.nacos.config.server.constant.Constants;
import com.alibaba.nacos.config.server.paramcheck.ConfigDefaultHttpParamExtractor;
import com.alibaba.nacos.config.server.utils.GroupKey2;
import com.alibaba.nacos.config.server.utils.ParamUtils;
import com.alibaba.nacos.core.cluster.Member;
import com.alibaba.nacos.core.cluster.ServerMemberManager;
import com.alibaba.nacos.core.controller.compatibility.Compatibility;
import com.alibaba.nacos.core.paramcheck.ExtractorManager;
import com.alibaba.nacos.core.remote.Connection;
import com.alibaba.nacos.core.remote.ConnectionManager;
import com.alibaba.nacos.core.utils.GenericType;
import com.alibaba.nacos.core.utils.Loggers;
import com.alibaba.nacos.plugin.auth.constant.ActionTypes;
import com.alibaba.nacos.plugin.auth.constant.ApiType;
import com.alibaba.nacos.plugin.auth.constant.SignType;
import com.alibaba.nacos.sys.env.EnvUtil;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

import static com.alibaba.nacos.api.config.remote.request.ClientConfigMetricRequest.MetricsKey.CACHE_DATA;
import static com.alibaba.nacos.api.config.remote.request.ClientConfigMetricRequest.MetricsKey.SNAPSHOT_DATA;

/**
 * ClientMetricsController.
 *
 * @author zunfei.lzf
 */
@RestController
@RequestMapping(Constants.METRICS_CONTROLLER_PATH)
@ExtractorManager.Extractor(httpExtractor = ConfigDefaultHttpParamExtractor.class)
public class ClientMetricsController {
    
    private final ServerMemberManager serverMemberManager;
    
    private final ConnectionManager connectionManager;
    
    public ClientMetricsController(ServerMemberManager serverMemberManager, ConnectionManager connectionManager) {
        this.serverMemberManager = serverMemberManager;
        this.connectionManager = connectionManager;
    }
    
    /**
     * get client metric.
     *
     * @param ip client ip .
     * @return ResponseEntity
     */
    @GetMapping("/cluster")
    @Secured(resource = Constants.METRICS_CONTROLLER_PATH, action = ActionTypes.READ, signType = SignType.CONFIG)
    @Compatibility(apiType = ApiType.ADMIN_API)
    public ResponseEntity metric(@RequestParam("ip") String ip,
            @RequestParam(value = "dataId", required = false) String dataId,
            @RequestParam(value = "group", required = false) String group,
            @RequestParam(value = "tenant", required = false) String tenant) throws NacosException {
    
        ParamUtils.checkTenant(tenant);
        tenant = NamespaceUtil.processNamespaceParameter(tenant);
        ParamUtils.checkParam(dataId, group, "default", "default");
    
        Loggers.CORE.info("Get cluster config metrics received, ip={},dataId={},group={},tenant={}", ip, dataId, group,
                tenant);
        Map<String, Object> responseMap = new HashMap<>(3);
        Collection<Member> members = serverMemberManager.allMembers();
        final NacosAsyncRestTemplate nacosAsyncRestTemplate = HttpClientBeanHolder.getNacosAsyncRestTemplate(
                Loggers.CLUSTER);
        CountDownLatch latch = new CountDownLatch(members.size());
        for (Member member : members) {
            String url = HttpUtils.buildUrl(false, member.getAddress(), EnvUtil.getContextPath(),
                    Constants.METRICS_CONTROLLER_PATH, "current");
            Query query = Query.newInstance().addParam("ip", ip).addParam("dataId", dataId).addParam("group", group)
                    .addParam("tenant", tenant);
            nacosAsyncRestTemplate.get(url, Header.EMPTY, query, new GenericType<Map>() {
            }.getType(), new ClusterMetricsCallBack(responseMap, latch, dataId, group, tenant, ip, member));
        }
        try {
            latch.await(3L, TimeUnit.SECONDS);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        
        return ResponseEntity.ok().body(responseMap);
    }
    
    static class ClusterMetricsCallBack implements Callback<Map> {
        
        Map<String, Object> responseMap;
        
        CountDownLatch latch;
        
        String dataId;
        
        String group;
        
        String tenant;
        
        String ip;
        
        Member member;
        
        public ClusterMetricsCallBack(Map<String, Object> responseMap, CountDownLatch latch, String dataId,
                String group, String tenant, String ip, Member member) {
            this.responseMap = responseMap;
            this.latch = latch;
            this.dataId = dataId;
            this.group = group;
            this.tenant = tenant;
            this.member = member;
            this.ip = ip;
        }
        
        @Override
        public void onReceive(RestResult<Map> result) {
            if (result.ok()) {
                responseMap.putAll(result.getData());
            }
            latch.countDown();
        }
        
        @Override
        public void onError(Throwable throwable) {
            Loggers.CORE.error(
                    "Get config metrics error from member address={}, ip={},dataId={},group={},tenant={},error={}",
                    member.getAddress(), ip, dataId, group, tenant, throwable);
            latch.countDown();
        }
        
        @Override
        public void onCancel() {
            latch.countDown();
        }
    }
    
    /**
     * Get client config listener lists of subscriber in local machine.
     */
    @GetMapping("/current")
    @Secured(resource = Constants.METRICS_CONTROLLER_PATH, action = ActionTypes.READ, signType = SignType.CONFIG)
    @Compatibility(apiType = ApiType.ADMIN_API)
    public Map<String, Object> getClientMetrics(@RequestParam("ip") String ip,
            @RequestParam(value = "dataId", required = false) String dataId,
            @RequestParam(value = "group", required = false) String group,
            @RequestParam(value = "tenant", required = false) String tenant) throws NacosException {
    
        ParamUtils.checkTenant(tenant);
        tenant = NamespaceUtil.processNamespaceParameter(tenant);
        ParamUtils.checkParam(dataId, group, "default", "default");
    
        Map<String, Object> metrics = new HashMap<>(16);
        List<Connection> connectionsByIp = connectionManager.getConnectionByIp(ip);
        for (Connection connectionByIp : connectionsByIp) {
            try {
                ClientConfigMetricRequest clientMetrics = new ClientConfigMetricRequest();
                if (StringUtils.isNotBlank(dataId)) {
                    clientMetrics.getMetricsKeys().add(ClientConfigMetricRequest.MetricsKey.build(CACHE_DATA,
                            GroupKey2.getKey(dataId, group, tenant)));
                    clientMetrics.getMetricsKeys().add(ClientConfigMetricRequest.MetricsKey.build(SNAPSHOT_DATA,
                            GroupKey2.getKey(dataId, group, tenant)));
                }
                
                ClientConfigMetricResponse request1 = (ClientConfigMetricResponse) connectionByIp.request(clientMetrics,
                        1000L);
                metrics.putAll(request1.getMetrics());
            } catch (Exception e) {
                Loggers.CORE.error("Get config metrics error from client ip={},dataId={},group={},tenant={},error={}",
                        ip, dataId, group, tenant, e);
            }
        }
        return metrics;
        
    }
    
}
