/*
 * 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.
 */

package org.elasticsearch.action.admin.cluster.allocation;

import org.elasticsearch.action.support.ActiveShardCount;
import org.elasticsearch.cluster.ClusterInfo;
import org.elasticsearch.cluster.ClusterState;
import org.elasticsearch.cluster.health.ClusterHealthStatus;
import org.elasticsearch.cluster.node.DiscoveryNode;
import org.elasticsearch.cluster.routing.ShardRouting;
import org.elasticsearch.cluster.routing.ShardRoutingState;
import org.elasticsearch.cluster.routing.UnassignedInfo;
import org.elasticsearch.cluster.routing.UnassignedInfo.AllocationStatus;
import org.elasticsearch.cluster.routing.UnassignedInfo.Reason;
import org.elasticsearch.cluster.routing.allocation.AllocateUnassignedDecision;
import org.elasticsearch.cluster.routing.allocation.AllocationDecision;
import org.elasticsearch.cluster.routing.allocation.MoveDecision;
import org.elasticsearch.cluster.routing.allocation.NodeAllocationResult;
import org.elasticsearch.cluster.routing.allocation.decider.Decision;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.util.set.Sets;
import org.elasticsearch.common.xcontent.ToXContent;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.common.xcontent.XContentParser.Token;
import org.elasticsearch.common.xcontent.json.JsonXContent;
import org.elasticsearch.index.shard.ShardId;
import org.elasticsearch.test.ESIntegTestCase;
import org.elasticsearch.test.InternalTestCluster;
import org.elasticsearch.test.junit.annotations.TestLogging;

import java.io.IOException;
import java.util.*;

import static org.hamcrest.Matchers.*;

/**
 * Tests for the cluster allocation explanation
 */
@ESIntegTestCase.ClusterScope(scope = ESIntegTestCase.Scope.TEST, numDataNodes = 0)
public final class ClusterBugIT extends ESIntegTestCase {

    //@TestLogging("org.elasticsearch:DEBUG")
    public void testBug() throws Exception {
        List<String> nodes = internalCluster().startNodes(6);
        Set<String> excludeNodes = new HashSet<>(nodes.subList(0, 3));
        Set<String> includeNodes = new HashSet<>(nodes.subList(3, 6));
        logger.info("--> exclude: [{}], include: [{}]",
            Strings.collectionToCommaDelimitedString(excludeNodes),
            Strings.collectionToCommaDelimitedString(includeNodes));
        ensureStableCluster(6);
        client().admin().indices().prepareCreate("test").get();
        ensureGreen("test");

        Settings exclude = Settings.builder().put("cluster.routing.allocation.exclude._name",
            Strings.collectionToCommaDelimitedString(excludeNodes)).build();

        logger.info("--> updating settings");
        client().admin().cluster().prepareUpdateSettings().setTransientSettings(exclude).get();

        logger.info("--> waiting for relocation");
        waitForRelocation(ClusterHealthStatus.GREEN);

        ClusterState state = client().admin().cluster().prepareState().get().getState();

        for (ShardRouting shard : state.getRoutingTable().shardsWithState(ShardRoutingState.STARTED)) {
            String node = state.getRoutingNodes().node(shard.currentNodeId()).node().getName();
            logger.info("--> shard on {} - {}", node, shard);
            assertTrue("shard on " + node + " but should only be on the include node list: " +
                    Strings.collectionToCommaDelimitedString(includeNodes),
                includeNodes.contains(node));
        }

        Settings other = Settings.builder().put("cluster.info.update.interval", "45s").build();

        logger.info("--> updating settings with random persistent setting");
        client().admin().cluster().prepareUpdateSettings()
            .setPersistentSettings(other).setTransientSettings(exclude).get();

        logger.info("--> waiting for relocation");
        waitForRelocation(ClusterHealthStatus.GREEN);

        state = client().admin().cluster().prepareState().get().getState();

        // The transient settings still exist in the state
        assertThat(state.metaData().transientSettings(), equalTo(exclude));

        for (ShardRouting shard : state.getRoutingTable().shardsWithState(ShardRoutingState.STARTED)) {
            String node = state.getRoutingNodes().node(shard.currentNodeId()).node().getName();
            logger.info("--> shard on {} - {}", node, shard);
            assertTrue("shard on " + node + " but should only be on the include node list: " +
                    Strings.collectionToCommaDelimitedString(includeNodes),
                includeNodes.contains(node));
        }
    }
}