/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.dubbo.rpc.cluster.filter.support;


import org.apache.dubbo.common.extension.Activate;
import org.apache.dubbo.metrics.collector.DefaultMetricsCollector;
import org.apache.dubbo.metrics.event.MetricsEventBus;
import org.apache.dubbo.metrics.event.RequestBeforeEvent;
import org.apache.dubbo.rpc.BaseFilter;
import org.apache.dubbo.rpc.Invocation;
import org.apache.dubbo.rpc.Invoker;
import org.apache.dubbo.rpc.Result;
import org.apache.dubbo.rpc.RpcException;
import org.apache.dubbo.rpc.cluster.filter.ClusterFilter;
import org.apache.dubbo.rpc.model.ApplicationModel;
import org.apache.dubbo.rpc.model.ScopeModelAware;

import static org.apache.dubbo.common.constants.CommonConstants.CONSUMER;

@Activate(group = CONSUMER, onClass = "org.apache.dubbo.metrics.collector.DefaultMetricsCollector")
public class MetricsClusterFilter implements ClusterFilter, BaseFilter.Listener, ScopeModelAware {

    private ApplicationModel applicationModel;
    private DefaultMetricsCollector collector;

    @Override
    public void setApplicationModel(ApplicationModel applicationModel) {
        this.applicationModel = applicationModel;
        this.collector = applicationModel.getBeanFactory().getBean(DefaultMetricsCollector.class);
    }

    @Override
    public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
        return invoker.invoke(invocation);
    }

    @Override
    public void onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
        handleMethodException(result.getException(), invocation);
    }

    @Override
    public void onError(Throwable t, Invoker<?> invoker, Invocation invocation) {
        handleMethodException(t, invocation);
    }

    private void handleMethodException(Throwable t, Invocation invocation) {
        if (collector == null || !collector.isCollectEnabled()) {
            return;
        }
        if (t instanceof RpcException) {
            RpcException e = (RpcException) t;
            if (e.isForbidden()) {
                MetricsEventBus.publish(RequestBeforeEvent.toEvent(applicationModel, invocation));
            }
        }
    }

}
