/*
 * SPDX-License-Identifier: Apache-2.0
 *
 * The OpenSearch Contributors require contributions made to
 * this file be licensed under the Apache-2.0 license or a
 * compatible open source license.
 */

/*
 * Licensed to Elasticsearch under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch 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
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/*
 * Modifications Copyright OpenSearch Contributors. See
 * GitHub history for details.
 */

package org.opensearch.cluster.metadata;

import org.opensearch.action.admin.indices.mapping.put.PutMappingClusterStateUpdateRequest;
import org.opensearch.cluster.ClusterState;
import org.opensearch.cluster.ClusterStateTaskExecutor;
import org.opensearch.cluster.service.ClusterService;
import org.opensearch.common.compress.CompressedXContent;
import org.opensearch.core.index.Index;
import org.opensearch.index.IndexService;
import org.opensearch.plugins.Plugin;
import org.opensearch.test.OpenSearchSingleNodeTestCase;
import org.opensearch.test.InternalSettingsPlugin;

import java.util.Collection;
import java.util.Collections;

import static org.hamcrest.Matchers.equalTo;
import static org.hamcrest.Matchers.not;

public class MetadataMappingServiceTests extends OpenSearchSingleNodeTestCase {

    @Override
    protected Collection<Class<? extends Plugin>> getPlugins() {
        return Collections.singleton(InternalSettingsPlugin.class);
    }

    public void testMappingClusterStateUpdateDoesntChangeExistingIndices() throws Exception {
        final IndexService indexService = createIndex("test", client().admin().indices().prepareCreate("test").setMapping());
        final CompressedXContent currentMapping = indexService.mapperService().documentMapper().mappingSource();

        final MetadataMappingService mappingService = getInstanceFromNode(MetadataMappingService.class);
        final ClusterService clusterService = getInstanceFromNode(ClusterService.class);
        // TODO - it will be nice to get a random mapping generator
        final PutMappingClusterStateUpdateRequest request = new PutMappingClusterStateUpdateRequest(
            "{ \"properties\": { \"field\": { \"type\": \"text\" }}}"
        );
        request.indices(new Index[] { indexService.index() });
        final ClusterStateTaskExecutor.ClusterTasksResult<PutMappingClusterStateUpdateRequest> result = mappingService.putMappingExecutor
            .execute(clusterService.state(), Collections.singletonList(request));
        // the task completed successfully
        assertThat(result.executionResults.size(), equalTo(1));
        assertTrue(result.executionResults.values().iterator().next().isSuccess());
        // the task really was a mapping update
        assertThat(
            indexService.mapperService().documentMapper().mappingSource(),
            not(equalTo(result.resultingState.metadata().index("test").mapping().source()))
        );
        // since we never committed the cluster state update, the in-memory state is unchanged
        assertThat(indexService.mapperService().documentMapper().mappingSource(), equalTo(currentMapping));
    }

    public void testClusterStateIsNotChangedWithIdenticalMappings() throws Exception {
        createIndex("test", client().admin().indices().prepareCreate("test"));

        final MetadataMappingService mappingService = getInstanceFromNode(MetadataMappingService.class);
        final ClusterService clusterService = getInstanceFromNode(ClusterService.class);
        final PutMappingClusterStateUpdateRequest request = new PutMappingClusterStateUpdateRequest(
            "{ \"properties\" { \"field\": { \"type\": \"text\" }}}"
        );
        ClusterState result = mappingService.putMappingExecutor.execute(
            clusterService.state(),
            Collections.singletonList(request)
        ).resultingState;

        assertFalse(result != clusterService.state());

        ClusterState result2 = mappingService.putMappingExecutor.execute(result, Collections.singletonList(request)).resultingState;

        assertSame(result, result2);
    }

    public void testMappingVersion() throws Exception {
        final IndexService indexService = createIndex("test", client().admin().indices().prepareCreate("test"));
        final long previousVersion = indexService.getMetadata().getMappingVersion();
        final MetadataMappingService mappingService = getInstanceFromNode(MetadataMappingService.class);
        final ClusterService clusterService = getInstanceFromNode(ClusterService.class);
        final PutMappingClusterStateUpdateRequest request = new PutMappingClusterStateUpdateRequest(
            "{ \"properties\": { \"field\": { \"type\": \"text\" }}}"
        );
        request.indices(new Index[] { indexService.index() });
        final ClusterStateTaskExecutor.ClusterTasksResult<PutMappingClusterStateUpdateRequest> result = mappingService.putMappingExecutor
            .execute(clusterService.state(), Collections.singletonList(request));
        assertThat(result.executionResults.size(), equalTo(1));
        assertTrue(result.executionResults.values().iterator().next().isSuccess());
        assertThat(result.resultingState.metadata().index("test").getMappingVersion(), equalTo(1 + previousVersion));
    }

    public void testMappingVersionUnchanged() throws Exception {
        final IndexService indexService = createIndex("test", client().admin().indices().prepareCreate("test").setMapping());
        final long previousVersion = indexService.getMetadata().getMappingVersion();
        final MetadataMappingService mappingService = getInstanceFromNode(MetadataMappingService.class);
        final ClusterService clusterService = getInstanceFromNode(ClusterService.class);
        final PutMappingClusterStateUpdateRequest request = new PutMappingClusterStateUpdateRequest("{ \"properties\": {}}");
        request.indices(new Index[] { indexService.index() });
        final ClusterStateTaskExecutor.ClusterTasksResult<PutMappingClusterStateUpdateRequest> result = mappingService.putMappingExecutor
            .execute(clusterService.state(), Collections.singletonList(request));
        assertThat(result.executionResults.size(), equalTo(1));
        assertTrue(result.executionResults.values().iterator().next().isSuccess());
        assertThat(result.resultingState.metadata().index("test").getMappingVersion(), equalTo(previousVersion));
    }
}