/*
 * 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.skywalking.banyandb.v1.client;

import io.grpc.ServerServiceDefinition;
import io.grpc.stub.StreamObserver;
import org.apache.skywalking.banyandb.common.v1.BanyandbCommon;
import org.apache.skywalking.banyandb.measure.v1.BanyandbMeasure;
import org.apache.skywalking.banyandb.measure.v1.MeasureServiceGrpc;
import org.apache.skywalking.banyandb.model.v1.BanyandbModel;
import org.apache.skywalking.banyandb.v1.client.grpc.exception.BanyanDBException;
import org.apache.skywalking.banyandb.v1.client.metadata.Duration;
import org.apache.skywalking.banyandb.v1.client.metadata.IndexRule;
import org.apache.skywalking.banyandb.v1.client.metadata.IndexRuleBinding;
import org.apache.skywalking.banyandb.v1.client.metadata.Measure;
import org.apache.skywalking.banyandb.v1.client.metadata.MeasureMetadataRegistry;
import org.apache.skywalking.banyandb.v1.client.metadata.TagFamilySpec;

import lombok.SneakyThrows;
import org.junit.After;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;

import java.io.IOException;
import java.time.Instant;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

import static com.google.common.base.Preconditions.checkNotNull;

public class BanyanDBClientMeasureWriteTest extends AbstractBanyanDBClientTest {
    private MeasureBulkWriteProcessor measureBulkWriteProcessor;
    private Measure measure;

    @Before
    public void setUp() throws IOException, BanyanDBException {
        measureRegistry = new HashMap<>();
        setUp(bindMeasureRegistry());

        measureBulkWriteProcessor = client.buildMeasureWriteProcessor(1000, 1, 1);

        measure = Measure.create("sw_metric", "service_cpm_minute", Duration.ofHours(1))
                .setEntityRelativeTags("entity_id")
                .addTagFamily(TagFamilySpec.create("default")
                        .addTagSpec(TagFamilySpec.TagSpec.newStringTag("entity_id"))
                        .build())
                .addField(Measure.FieldSpec.newIntField("total").compressWithZSTD().encodeWithGorilla().build())
                .addField(Measure.FieldSpec.newIntField("value").compressWithZSTD().encodeWithGorilla().build())
                .addIndex(IndexRule.create("scope", IndexRule.IndexType.INVERTED))
                .build();
        client.define(measure);
    }

    @After
    public void shutdown() throws IOException {
        measureBulkWriteProcessor.close();
    }

    @Test
    public void testRegistry() {
        Assert.assertEquals(indexRuleBindingRegistry.size(), 1);
        Assert.assertTrue(indexRuleBindingRegistry.containsKey(IndexRuleBinding.defaultBindingRule("service_cpm_minute")));
        Assert.assertEquals(indexRuleBindingRegistry.get(IndexRuleBinding.defaultBindingRule("service_cpm_minute")).getSubject().getCatalog(),
                BanyandbCommon.Catalog.CATALOG_MEASURE);
    }

    @Test
    public void testWrite() throws Exception {
        final CountDownLatch allRequestsDelivered = new CountDownLatch(1);
        final List<BanyandbMeasure.WriteRequest> writeRequestDelivered = new ArrayList<>();

        // implement the fake service
        final ServerServiceDefinition serviceImpl = createService(allRequestsDelivered, writeRequestDelivered);
        serviceRegistry.addService(serviceImpl);

        Instant now = Instant.now();
        MeasureWrite measureWrite = client.createMeasureWrite("sw_metric", "service_cpm_minute", now.toEpochMilli());
        measureWrite.tag("entity_id", TagAndValue.stringTagValue("entity_1"))
                .field("total", TagAndValue.longFieldValue(100))
                .field("value", TagAndValue.longFieldValue(1));

        measureBulkWriteProcessor.add(measureWrite);

        if (allRequestsDelivered.await(5, TimeUnit.SECONDS)) {
            Assert.assertEquals(1, writeRequestDelivered.size());
            final BanyandbMeasure.WriteRequest request = writeRequestDelivered.get(0);
            Assert.assertEquals(1, request.getDataPoint().getTagFamilies(0).getTagsCount());
            Assert.assertEquals("entity_1", request.getDataPoint().getTagFamilies(0).getTags(0).getStr().getValue());
            Assert.assertEquals(100, request.getDataPoint().getFields(0).getInt().getValue());
            Assert.assertEquals(1, request.getDataPoint().getFields(1).getInt().getValue());
            Assert.assertTrue(request.getMessageId() > 0);
        } else {
            Assert.fail();
        }
    }

    @Test
    public void testAutoRefreshSchema() throws Exception {
        CountDownLatch allRequestsDelivered = new CountDownLatch(1);
        List<BanyandbMeasure.WriteRequest> writeRequestDelivered = new ArrayList<>();
        ServerServiceDefinition serviceImpl = createService(allRequestsDelivered, writeRequestDelivered);
        serviceRegistry.addService(serviceImpl);

        Instant now = Instant.now();
        MeasureWrite measureWrite = client.createMeasureWrite("sw_metric", "service_cpm_minute", now.toEpochMilli());
        measureWrite.tag("entity_id", TagAndValue.stringTagValue("entity_1"))
                .field("total", TagAndValue.longFieldValue(100))
                .field("value", TagAndValue.longFieldValue(1));

        // update schema
        Measure measureUpdate = measure.toBuilder()
                .addField(Measure.FieldSpec.newIntField("new_field").compressWithZSTD().encodeWithGorilla().build())
                .build();
        MeasureMetadataRegistry measureMetadataRegistry = new MeasureMetadataRegistry(checkNotNull(this.channel));
        measureMetadataRegistry.update(measureUpdate);

        measureBulkWriteProcessor.add(measureWrite);
        if (allRequestsDelivered.await(5, TimeUnit.SECONDS)) {
            Assert.assertEquals(0, writeRequestDelivered.size());
        } else {
            Assert.fail();
        }

        // rewrite
        serviceRegistry.removeService(serviceImpl);
        allRequestsDelivered = new CountDownLatch(1);
        writeRequestDelivered = new ArrayList<>();
        serviceImpl = createService(allRequestsDelivered, writeRequestDelivered);
        serviceRegistry.addService(serviceImpl);

        now = Instant.now();
        measureWrite = client.createMeasureWrite("sw_metric", "service_cpm_minute", now.toEpochMilli());
        measureWrite.tag("entity_id", TagAndValue.stringTagValue("entity_1"))
                .field("total", TagAndValue.longFieldValue(100))
                .field("value", TagAndValue.longFieldValue(1));

        measureBulkWriteProcessor.add(measureWrite);
        if (allRequestsDelivered.await(5, TimeUnit.SECONDS)) {
            Assert.assertEquals(1, writeRequestDelivered.size());
            final BanyandbMeasure.WriteRequest request = writeRequestDelivered.get(0);
            Assert.assertEquals(1, request.getDataPoint().getTagFamilies(0).getTagsCount());
            Assert.assertEquals("entity_1", request.getDataPoint().getTagFamilies(0).getTags(0).getStr().getValue());
            Assert.assertEquals(100, request.getDataPoint().getFields(0).getInt().getValue());
            Assert.assertEquals(1, request.getDataPoint().getFields(1).getInt().getValue());
            Assert.assertTrue(request.getMessageId() > 0);
        } else {
            Assert.fail();
        }
    }

    @SneakyThrows
    private boolean checkSchemaExpired(BanyandbMeasure.WriteRequest request) {
        Measure m = client.findMeasure(request.getMetadata().getGroup(), request.getMetadata().getName());
        return request.getMetadata().getModRevision() != m.serialize().getMetadata().getModRevision();
    }

    private ServerServiceDefinition createService(final CountDownLatch allRequestsDelivered,
                                                  final List<BanyandbMeasure.WriteRequest> writeRequestDelivered) {
        return new MeasureServiceGrpc.MeasureServiceImplBase() {
            @Override
            public StreamObserver<BanyandbMeasure.WriteRequest> write(StreamObserver<BanyandbMeasure.WriteResponse> responseObserver) {
                return new StreamObserver<BanyandbMeasure.WriteRequest>() {
                    @Override
                    public void onNext(BanyandbMeasure.WriteRequest request) {
                        if (checkSchemaExpired(request)) {
                            responseObserver.onNext(
                                    BanyandbMeasure.WriteResponse.newBuilder()
                                            .setMetadata(request.getMetadata())
                                            .setStatus(BanyandbModel.Status.STATUS_EXPIRED_SCHEMA)
                                            .setMessageId(request.getMessageId())
                                            .build());
                        } else {
                            writeRequestDelivered.add(request);
                            responseObserver.onNext(BanyandbMeasure.WriteResponse.newBuilder().setMessageId(request.getMessageId()).build());
                        }
                    }

                    @Override
                    public void onError(Throwable t) {
                    }

                    @Override
                    public void onCompleted() {
                        responseObserver.onCompleted();
                        allRequestsDelivered.countDown();
                    }
                };
            }
        }.bindService();
    }
}