/*
 * 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
 * under the License.
 */

/*
 * Modifications Copyright OpenSearch Contributors. See
 * GitHub history for details.
 */

package org.opensearch.action.admin.indices.settings.get;

import org.opensearch.action.IndicesRequest;
import org.opensearch.action.support.ActionFilters;
import org.opensearch.action.support.replication.ClusterStateCreationUtils;
import org.opensearch.cluster.ClusterState;
import org.opensearch.cluster.metadata.IndexNameExpressionResolver;
import org.opensearch.cluster.service.ClusterService;
import org.opensearch.common.settings.IndexScopedSettings;
import org.opensearch.common.settings.Settings;
import org.opensearch.common.settings.SettingsFilter;
import org.opensearch.common.settings.SettingsModule;
import org.opensearch.common.util.concurrent.ThreadContext;
import org.opensearch.core.action.ActionListener;
import org.opensearch.core.index.Index;
import org.opensearch.telemetry.tracing.noop.NoopTracer;
import org.opensearch.test.OpenSearchTestCase;
import org.opensearch.test.transport.CapturingTransport;
import org.opensearch.threadpool.TestThreadPool;
import org.opensearch.threadpool.ThreadPool;
import org.opensearch.transport.TransportService;
import org.junit.After;
import org.junit.Before;

import java.util.Collections;
import java.util.concurrent.TimeUnit;

import static java.util.Collections.emptyList;
import static java.util.Collections.emptySet;
import static org.opensearch.test.ClusterServiceUtils.createClusterService;

public class GetSettingsActionTests extends OpenSearchTestCase {

    private TransportService transportService;
    private ClusterService clusterService;
    private ThreadPool threadPool;
    private SettingsFilter settingsFilter;
    private final String indexName = "test_index";

    private TestTransportGetSettingsAction getSettingsAction;

    class TestTransportGetSettingsAction extends TransportGetSettingsAction {
        TestTransportGetSettingsAction() {
            super(
                GetSettingsActionTests.this.transportService,
                GetSettingsActionTests.this.clusterService,
                GetSettingsActionTests.this.threadPool,
                settingsFilter,
                new ActionFilters(Collections.emptySet()),
                new Resolver(),
                IndexScopedSettings.DEFAULT_SCOPED_SETTINGS
            );
        }

        @Override
        protected void clusterManagerOperation(
            GetSettingsRequest request,
            ClusterState state,
            ActionListener<GetSettingsResponse> listener
        ) {
            ClusterState stateWithIndex = ClusterStateCreationUtils.state(indexName, 1, 1);
            super.clusterManagerOperation(request, stateWithIndex, listener);
        }
    }

    @Before
    public void setUp() throws Exception {
        super.setUp();

        settingsFilter = new SettingsModule(Settings.EMPTY, emptyList(), emptyList(), emptySet()).getSettingsFilter();
        threadPool = new TestThreadPool("GetSettingsActionTests");
        clusterService = createClusterService(threadPool);
        CapturingTransport capturingTransport = new CapturingTransport();
        transportService = capturingTransport.createTransportService(
            clusterService.getSettings(),
            threadPool,
            TransportService.NOOP_TRANSPORT_INTERCEPTOR,
            boundAddress -> clusterService.localNode(),
            null,
            Collections.emptySet(),
            NoopTracer.INSTANCE
        );
        transportService.start();
        transportService.acceptIncomingRequests();
        getSettingsAction = new GetSettingsActionTests.TestTransportGetSettingsAction();
    }

    @After
    public void tearDown() throws Exception {
        ThreadPool.terminate(threadPool, 30, TimeUnit.SECONDS);
        threadPool = null;
        clusterService.close();
        super.tearDown();
    }

    public void testIncludeDefaults() {
        GetSettingsRequest noDefaultsRequest = new GetSettingsRequest().indices(indexName);
        getSettingsAction.execute(null, noDefaultsRequest, ActionListener.wrap(noDefaultsResponse -> {
            assertNull(
                "index.refresh_interval should be null as it was never set",
                noDefaultsResponse.getSetting(indexName, "index.refresh_interval")
            );
        }, exception -> { throw new AssertionError(exception); }));

        GetSettingsRequest defaultsRequest = new GetSettingsRequest().indices(indexName).includeDefaults(true);

        getSettingsAction.execute(null, defaultsRequest, ActionListener.wrap(defaultsResponse -> {
            assertNotNull(
                "index.refresh_interval should be set as we are including defaults",
                defaultsResponse.getSetting(indexName, "index.refresh_interval")
            );
        }, exception -> { throw new AssertionError(exception); }));

    }

    public void testIncludeDefaultsWithFiltering() {
        GetSettingsRequest defaultsRequest = new GetSettingsRequest().indices(indexName)
            .includeDefaults(true)
            .names("index.refresh_interval");
        getSettingsAction.execute(null, defaultsRequest, ActionListener.wrap(defaultsResponse -> {
            assertNotNull(
                "index.refresh_interval should be set as we are including defaults",
                defaultsResponse.getSetting(indexName, "index.refresh_interval")
            );
            assertNull(
                "index.number_of_shards should be null as this query is filtered",
                defaultsResponse.getSetting(indexName, "index.number_of_shards")
            );
            assertNull(
                "index.warmer.enabled should be null as this query is filtered",
                defaultsResponse.getSetting(indexName, "index.warmer.enabled")
            );
        }, exception -> { throw new AssertionError(exception); }));
    }

    static class Resolver extends IndexNameExpressionResolver {
        Resolver() {
            super(new ThreadContext(Settings.EMPTY));
        }

        @Override
        public String[] concreteIndexNames(ClusterState state, IndicesRequest request) {
            return request.indices();
        }

        @Override
        public Index[] concreteIndices(ClusterState state, IndicesRequest request) {
            Index[] out = new Index[request.indices().length];
            for (int x = 0; x < out.length; x++) {
                out[x] = new Index(request.indices()[x], "_na_");
            }
            return out;
        }
    }
}
