/*
 * 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.env;

import org.opensearch.Version;
import org.opensearch.cluster.node.DiscoveryNodeRole;
import org.opensearch.common.CheckedConsumer;
import org.opensearch.common.io.PathUtils;
import org.opensearch.common.settings.Settings;
import org.opensearch.gateway.PersistedClusterStateService;
import org.opensearch.indices.IndicesService;
import org.opensearch.test.InternalTestCluster;
import org.opensearch.test.NodeRoles;
import org.opensearch.test.OpenSearchIntegTestCase;

import java.io.IOException;
import java.nio.file.Path;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;

import static org.opensearch.test.NodeRoles.nonDataNode;
import static org.hamcrest.Matchers.allOf;
import static org.hamcrest.Matchers.containsString;
import static org.hamcrest.Matchers.endsWith;
import static org.hamcrest.Matchers.startsWith;

@OpenSearchIntegTestCase.ClusterScope(scope = OpenSearchIntegTestCase.Scope.TEST, numDataNodes = 0)
public class NodeEnvironmentIT extends OpenSearchIntegTestCase {
    public void testStartFailureOnDataForNonDataNode() throws Exception {
        final String indexName = "test-fail-on-data";

        logger.info("--> starting one node");
        final boolean writeDanglingIndices = randomBoolean();
        String node = internalCluster().startNode(
            Settings.builder().put(IndicesService.WRITE_DANGLING_INDICES_INFO_SETTING.getKey(), writeDanglingIndices).build()
        );
        Settings dataPathSettings = internalCluster().dataPathSettings(node);

        logger.info("--> creating index");
        prepareCreate(indexName, Settings.builder().put("index.number_of_shards", 1).put("index.number_of_replicas", 0)).get();
        final String indexUUID = resolveIndex(indexName).getUUID();
        if (writeDanglingIndices) {
            assertBusy(
                () -> internalCluster().getInstances(IndicesService.class)
                    .forEach(indicesService -> assertTrue(indicesService.allPendingDanglingIndicesWritten()))
            );
        }

        logger.info("--> restarting the node without the data and cluster-manager roles");
        IllegalStateException ex = expectThrows(
            IllegalStateException.class,
            "node not having the data and cluster-manager roles while having existing index metadata must fail",
            () -> internalCluster().restartRandomDataNode(new InternalTestCluster.RestartCallback() {
                @Override
                public Settings onNodeStopped(String nodeName) {
                    return NodeRoles.removeRoles(
                        Collections.unmodifiableSet(
                            new HashSet<>(Arrays.asList(DiscoveryNodeRole.DATA_ROLE, DiscoveryNodeRole.MASTER_ROLE))
                        )
                    );
                }
            })
        );
        if (writeDanglingIndices) {
            assertThat(ex.getMessage(), startsWith("node does not have the data and cluster_manager roles but has index metadata"));
        } else {
            assertThat(ex.getMessage(), startsWith("node does not have the data role but has shard data"));
        }

        logger.info("--> start the node again with data and cluster-manager roles");
        internalCluster().startNode(dataPathSettings);

        logger.info("--> indexing a simple document");
        client().prepareIndex(indexName).setId("1").setSource("field1", "value1").get();

        logger.info("--> restarting the node without the data role");
        ex = expectThrows(
            IllegalStateException.class,
            "node not having the data role while having existing shard data must fail",
            () -> internalCluster().restartRandomDataNode(new InternalTestCluster.RestartCallback() {
                @Override
                public Settings onNodeStopped(String nodeName) {
                    return nonDataNode();
                }
            })
        );
        assertThat(ex.getMessage(), containsString(indexUUID));
        assertThat(ex.getMessage(), startsWith("node does not have the data role but has shard data"));
    }

    private IllegalStateException expectThrowsOnRestart(CheckedConsumer<Path[], Exception> onNodeStopped) {
        internalCluster().startNode();
        final Path[] dataPaths = internalCluster().getInstance(NodeEnvironment.class).nodeDataPaths();
        return expectThrows(
            IllegalStateException.class,
            () -> internalCluster().restartRandomDataNode(new InternalTestCluster.RestartCallback() {
                @Override
                public Settings onNodeStopped(String nodeName) {
                    try {
                        onNodeStopped.accept(dataPaths);
                    } catch (Exception e) {
                        throw new AssertionError(e);
                    }
                    return Settings.EMPTY;
                }
            })
        );
    }

    public void testFailsToStartIfDowngraded() {
        final IllegalStateException illegalStateException = expectThrowsOnRestart(
            dataPaths -> PersistedClusterStateService.overrideVersion(NodeMetadataTests.tooNewVersion(), dataPaths)
        );
        assertThat(
            illegalStateException.getMessage(),
            allOf(startsWith("cannot downgrade a node from version ["), endsWith("] to version [" + Version.CURRENT + "]"))
        );
    }

    public void testFailsToStartIfUpgradedTooFar() {
        final IllegalStateException illegalStateException = expectThrowsOnRestart(
            dataPaths -> PersistedClusterStateService.overrideVersion(NodeMetadataTests.tooOldVersion(), dataPaths)
        );
        assertThat(
            illegalStateException.getMessage(),
            allOf(startsWith("cannot upgrade a node from version ["), endsWith("] directly to version [" + Version.CURRENT + "]"))
        );
    }

    public void testFailsToStartOnDataPathsFromMultipleNodes() throws IOException {
        final List<String> nodes = internalCluster().startNodes(2);
        ensureStableCluster(2);

        final List<String> node0DataPaths = Environment.PATH_DATA_SETTING.get(internalCluster().dataPathSettings(nodes.get(0)));
        final List<String> node1DataPaths = Environment.PATH_DATA_SETTING.get(internalCluster().dataPathSettings(nodes.get(1)));

        final List<String> allDataPaths = new ArrayList<>(node0DataPaths);
        allDataPaths.addAll(node1DataPaths);

        internalCluster().stopRandomNode(InternalTestCluster.nameFilter(nodes.get(1)));
        internalCluster().stopRandomNode(InternalTestCluster.nameFilter(nodes.get(0)));

        IllegalStateException illegalStateException = expectThrows(
            IllegalStateException.class,
            () -> PersistedClusterStateService.nodeMetadata(
                allDataPaths.stream().map(PathUtils::get).map(path -> NodeEnvironment.resolveNodePath(path, 0)).toArray(Path[]::new)
            )
        );

        assertThat(illegalStateException.getMessage(), containsString("unexpected node ID in metadata"));

        illegalStateException = expectThrows(
            IllegalStateException.class,
            () -> internalCluster().startNode(Settings.builder().putList(Environment.PATH_DATA_SETTING.getKey(), allDataPaths))
        );

        assertThat(illegalStateException.getMessage(), containsString("unexpected node ID in metadata"));

        final List<String> node0DataPathsPlusOne = new ArrayList<>(node0DataPaths);
        node0DataPathsPlusOne.add(createTempDir().toString());
        internalCluster().startNode(Settings.builder().putList(Environment.PATH_DATA_SETTING.getKey(), node0DataPathsPlusOne));

        final List<String> node1DataPathsPlusOne = new ArrayList<>(node1DataPaths);
        node1DataPathsPlusOne.add(createTempDir().toString());
        internalCluster().startNode(Settings.builder().putList(Environment.PATH_DATA_SETTING.getKey(), node1DataPathsPlusOne));

        ensureStableCluster(2);
    }
}
