/*
 * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
 * or more contributor license agreements. Licensed under the "Elastic License
 * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
 * Public License v 1"; you may not use this file except in compliance with, at
 * your election, the "Elastic License 2.0", the "GNU Affero General Public
 * License v3.0 only", or the "Server Side Public License, v 1".
 */

package org.elasticsearch.action.support.replication;

import org.elasticsearch.action.ActionListener;
import org.elasticsearch.action.support.PlainActionFuture;
import org.elasticsearch.action.support.RetryableAction;
import org.elasticsearch.common.UUIDs;
import org.elasticsearch.common.util.concurrent.EsExecutors;
import org.elasticsearch.core.TimeValue;
import org.elasticsearch.index.shard.IndexShardClosedException;
import org.elasticsearch.index.shard.ShardId;
import org.elasticsearch.test.ESTestCase;
import org.elasticsearch.threadpool.TestThreadPool;

import java.util.Collections;

public class PendingReplicationActionsTests extends ESTestCase {

    private TestThreadPool threadPool;
    private ShardId shardId;
    private PendingReplicationActions pendingReplication;

    @Override
    public void setUp() throws Exception {
        super.setUp();
        shardId = new ShardId("index", UUIDs.randomBase64UUID(), 0);
        threadPool = new TestThreadPool(getTestName());
        pendingReplication = new PendingReplicationActions(shardId, threadPool);
    }

    @Override
    public void tearDown() throws Exception {
        terminate(threadPool);
        super.tearDown();
    }

    public void testAllocationIdActionCanBeRun() {
        String allocationId = UUIDs.randomBase64UUID();
        PlainActionFuture<Void> future = new PlainActionFuture<>();
        pendingReplication.acceptNewTrackedAllocationIds(Collections.singleton(allocationId));
        TestAction action = new TestAction(future);
        pendingReplication.addPendingAction(allocationId, action);
        action.run();
        future.actionGet();
        assertTrue(future.isDone());
    }

    public void testMissingAllocationIdActionWillBeCancelled() {
        String allocationId = UUIDs.randomBase64UUID();
        PlainActionFuture<Void> future = new PlainActionFuture<>();
        TestAction action = new TestAction(future);
        pendingReplication.addPendingAction(allocationId, action);
        expectThrows(IndexShardClosedException.class, future::actionGet);
    }

    public void testAllocationIdActionWillBeCancelledIfTrackedAllocationChanges() {
        String allocationId = UUIDs.randomBase64UUID();
        PlainActionFuture<Void> future = new PlainActionFuture<>();
        pendingReplication.acceptNewTrackedAllocationIds(Collections.singleton(allocationId));
        TestAction action = new TestAction(future, false);
        pendingReplication.addPendingAction(allocationId, action);
        action.run();
        pendingReplication.acceptNewTrackedAllocationIds(Collections.emptySet());
        expectThrows(IndexShardClosedException.class, future::actionGet);
    }

    public void testAllocationIdActionWillBeCancelledOnClose() {
        String allocationId = UUIDs.randomBase64UUID();
        PlainActionFuture<Void> future = new PlainActionFuture<>();
        pendingReplication.acceptNewTrackedAllocationIds(Collections.singleton(allocationId));
        TestAction action = new TestAction(future, false);
        pendingReplication.addPendingAction(allocationId, action);
        action.run();
        pendingReplication.close();
        expectThrows(IndexShardClosedException.class, future::actionGet);
    }

    private class TestAction extends RetryableAction<Void> {

        private final boolean succeed;
        private final Exception retryable = new Exception();

        private TestAction(ActionListener<Void> listener) {
            this(listener, true);
        }

        private TestAction(ActionListener<Void> listener, boolean succeed) {
            super(
                logger,
                threadPool,
                TimeValue.timeValueMillis(1),
                TimeValue.timeValueMinutes(1),
                listener,
                EsExecutors.DIRECT_EXECUTOR_SERVICE
            );
            this.succeed = succeed;
        }

        @Override
        public void tryAction(ActionListener<Void> listener) {
            if (succeed) {
                listener.onResponse(null);
            } else {
                listener.onFailure(retryable);
            }
        }

        @Override
        public boolean shouldRetry(Exception e) {
            return retryable == e;
        }
    }
}