/*
 * 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.kafka.streams.processor.internals;

import org.apache.kafka.clients.admin.Admin;
import org.apache.kafka.clients.admin.AdminClientConfig;
import org.apache.kafka.clients.admin.ListOffsetsResult.ListOffsetsResultInfo;
import org.apache.kafka.clients.admin.OffsetSpec;
import org.apache.kafka.clients.consumer.Consumer;
import org.apache.kafka.common.KafkaException;
import org.apache.kafka.common.KafkaFuture;
import org.apache.kafka.common.Metric;
import org.apache.kafka.common.MetricName;
import org.apache.kafka.common.TopicPartition;
import org.apache.kafka.common.errors.TimeoutException;
import org.apache.kafka.streams.StreamsConfig;
import org.apache.kafka.streams.errors.StreamsException;
import org.apache.kafka.streams.processor.TaskId;

import java.util.Collection;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ExecutionException;
import java.util.function.Function;
import java.util.stream.Collectors;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class ClientUtils {
    private static final Logger LOG = LoggerFactory.getLogger(ClientUtils.class);

    public static final class QuietAdminClientConfig extends AdminClientConfig {
        QuietAdminClientConfig(final StreamsConfig streamsConfig) {
            // If you just want to look up admin configs, you don't care about the clientId
            super(streamsConfig.getAdminConfigs("dummy"), false);
        }
    }

    // currently admin client is shared among all threads
    public static String getSharedAdminClientId(final String clientId) {
        return clientId + "-admin";
    }

    public static String getConsumerClientId(final String threadClientId) {
        return threadClientId + "-consumer";
    }

    public static String getRestoreConsumerClientId(final String threadClientId) {
        return threadClientId + "-restore-consumer";
    }

    public static String getThreadProducerClientId(final String threadClientId) {
        return threadClientId + "-producer";
    }

    public static String getTaskProducerClientId(final String threadClientId, final TaskId taskId) {
        return threadClientId + "-" + taskId + "-producer";
    }

    public static Map<MetricName, Metric> consumerMetrics(final Consumer<byte[], byte[]> mainConsumer,
                                                          final Consumer<byte[], byte[]> restoreConsumer) {
        final Map<MetricName, ? extends Metric> consumerMetrics = mainConsumer.metrics();
        final Map<MetricName, ? extends Metric> restoreConsumerMetrics = restoreConsumer.metrics();
        final LinkedHashMap<MetricName, Metric> result = new LinkedHashMap<>();
        result.putAll(consumerMetrics);
        result.putAll(restoreConsumerMetrics);
        return result;
    }

    public static Map<MetricName, Metric> adminClientMetrics(final Admin adminClient) {
        final Map<MetricName, ? extends Metric> adminClientMetrics = adminClient.metrics();
        return new LinkedHashMap<>(adminClientMetrics);
    }

    public static Map<MetricName, Metric> producerMetrics(final Collection<StreamsProducer> producers) {
        final Map<MetricName, Metric> result = new LinkedHashMap<>();
        for (final StreamsProducer producer : producers) {
            final Map<MetricName, ? extends Metric> producerMetrics = producer.metrics();
            if (producerMetrics != null) {
                result.putAll(producerMetrics);
            }
        }
        return result;
    }

    /**
     * @throws StreamsException if the consumer throws an exception
     * @throws org.apache.kafka.common.errors.TimeoutException if the request times out
     */
    public static Map<TopicPartition, Long> fetchCommittedOffsets(final Set<TopicPartition> partitions,
                                                                  final Consumer<byte[], byte[]> consumer) {
        if (partitions.isEmpty()) {
            return Collections.emptyMap();
        }

        final Map<TopicPartition, Long> committedOffsets;
        try {
            // those which do not have a committed offset would default to 0
            committedOffsets = consumer.committed(partitions).entrySet().stream()
                .collect(Collectors.toMap(Map.Entry::getKey, e -> e.getValue() == null ? 0L : e.getValue().offset()));
        } catch (final TimeoutException e) {
            LOG.warn("The committed offsets request timed out, try increasing the consumer client's default.api.timeout.ms", e);
            throw e;
        } catch (final KafkaException e) {
            LOG.warn("The committed offsets request failed.", e);
            throw new StreamsException(String.format("Failed to retrieve end offsets for %s", partitions), e);
        }

        return committedOffsets;
    }

    public static KafkaFuture<Map<TopicPartition, ListOffsetsResultInfo>> fetchEndOffsetsFuture(final Collection<TopicPartition> partitions,
                                                                                                final Admin adminClient) {
        return adminClient.listOffsets(
            partitions.stream().collect(Collectors.toMap(Function.identity(), tp -> OffsetSpec.latest())))
            .all();
    }

    /**
     * A helper method that wraps the {@code Future#get} call and rethrows any thrown exception as a StreamsException
     * @throws StreamsException if the admin client request throws an exception
     */
    public static Map<TopicPartition, ListOffsetsResultInfo> getEndOffsets(final KafkaFuture<Map<TopicPartition, ListOffsetsResultInfo>> endOffsetsFuture) {
        try {
            return endOffsetsFuture.get();
        } catch (final RuntimeException | InterruptedException | ExecutionException e) {
            LOG.warn("The listOffsets request failed.", e);
            throw new StreamsException("Unable to obtain end offsets from kafka", e);
        }
    }

    /**
     * @throws StreamsException if the admin client request throws an exception
     */
    public static Map<TopicPartition, ListOffsetsResultInfo> fetchEndOffsets(final Collection<TopicPartition> partitions,
                                                                             final Admin adminClient) {
        if (partitions.isEmpty()) {
            return Collections.emptyMap();
        }
        return getEndOffsets(fetchEndOffsetsFuture(partitions, adminClient));
    }
}
