/*
 * 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.paimon.flink.sink;

import org.apache.paimon.annotation.VisibleForTesting;

import org.apache.flink.metrics.Counter;
import org.apache.flink.metrics.MeterView;
import org.apache.flink.metrics.MetricGroup;
import org.apache.flink.metrics.SimpleCounter;
import org.apache.flink.metrics.groups.OperatorIOMetricGroup;
import org.apache.flink.metrics.groups.OperatorMetricGroup;
import org.apache.flink.runtime.metrics.MetricNames;

/** Flink metrics for {@link Committer}. */
public class CommitterMetrics {

    private static final String SINK_METRIC_GROUP = "sink";

    private final Counter numBytesOutCounter;
    private final Counter numRecordsOutCounter;

    public CommitterMetrics(MetricGroup metricGroup) {
        MetricGroup sinkMetricGroup;

        // When the committer runs as a regular operator we can wire its counters into the
        // operator's IO metric group; when it runs inside an OperatorCoordinator the coordinator
        // exposes a plain MetricGroup, so we fall back to local SimpleCounters.
        if (metricGroup instanceof OperatorMetricGroup) {
            OperatorIOMetricGroup operatorIOMetricGroup =
                    ((OperatorMetricGroup) metricGroup).getIOMetricGroup();
            sinkMetricGroup = operatorIOMetricGroup.addGroup(SINK_METRIC_GROUP);
            numBytesOutCounter = operatorIOMetricGroup.getNumBytesOutCounter();
            numRecordsOutCounter = operatorIOMetricGroup.getNumRecordsOutCounter();
        } else {
            sinkMetricGroup = metricGroup.addGroup(SINK_METRIC_GROUP);
            numBytesOutCounter = new SimpleCounter();
            numRecordsOutCounter = new SimpleCounter();
        }

        sinkMetricGroup.counter(MetricNames.IO_NUM_BYTES_OUT, numBytesOutCounter);
        sinkMetricGroup.meter(MetricNames.IO_NUM_BYTES_OUT_RATE, new MeterView(numBytesOutCounter));

        sinkMetricGroup.counter(MetricNames.IO_NUM_RECORDS_OUT, numRecordsOutCounter);
        sinkMetricGroup.meter(
                MetricNames.IO_NUM_RECORDS_OUT_RATE, new MeterView(numRecordsOutCounter));
    }

    public void increaseNumBytesOut(long numBytesOut) {
        numBytesOutCounter.inc(numBytesOut);
    }

    public void increaseNumRecordsOut(long numRecordsOut) {
        numRecordsOutCounter.inc(numRecordsOut);
    }

    @VisibleForTesting
    public Counter getNumBytesOutCounter() {
        return numBytesOutCounter;
    }

    @VisibleForTesting
    public Counter getNumRecordsOutCounter() {
        return numRecordsOutCounter;
    }
}
