/**
 *    Copyright (C) 2020-present MongoDB, Inc.
 *
 *    This program is free software: you can redistribute it and/or modify
 *    it under the terms of the Server Side Public License, version 1,
 *    as published by MongoDB, Inc.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    Server Side Public License for more details.
 *
 *    You should have received a copy of the Server Side Public License
 *    along with this program. If not, see
 *    <http://www.mongodb.com/licensing/server-side-public-license>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the Server Side Public License in all respects for
 *    all of the code used other than as permitted herein. If you modify file(s)
 *    with this exception, you may extend this exception to your version of the
 *    file(s), but you are not obligated to do so. If you do not wish to do so,
 *    delete this exception statement from your version. If you delete this
 *    exception statement from all source files in the program, then also delete
 *    it in the license file.
 */
#pragma once

#include <list>

#include <boost/optional.hpp>

#include "mongo/db/namespace_string.h"
#include "mongo/executor/task_executor.h"
#include "mongo/s/catalog/type_chunk.h"

namespace mongo {

class BSONObj;

// The maximum number of documents to delete in a single batch during range deletion.
// secondaryThrottle and rangeDeleterBatchDelayMS apply between each batch.
// Must be positive or 0 (the default), which means to use the value of
// internalQueryExecYieldIterations (or 1 if that's negative or zero).
extern AtomicWord<int> rangeDeleterBatchSize;

// After completing a batch of document deletions, the time in millis to wait before commencing the
// next batch of deletions.
extern AtomicWord<int> rangeDeleterBatchDelayMS;

/**
 * Deletes a range of orphaned documents for the given namespace and collection UUID. Returns a
 * future which will be resolved when the range has finished being deleted. The resulting future
 * will contain an error in cases where the range could not be deleted successfully.
 *
 * The overall algorithm is as follows:
 * 1. Wait for the all active queries which could be using the range to resolve by waiting
 *    for the waitForActiveQueriesToComplete future to resolve.
 * 2. Waits for delayForActiveQueriesOnSecondariesToComplete seconds before deleting any documents,
 *    to give queries running on secondaries a chance to finish.
 * 3. Delete documents in a series of batches with up to numDocsToRemovePerBatch documents per
 *    batch, with a delay of delayBetweenBatches milliseconds in between batches.
 */
SharedSemiFuture<void> removeDocumentsInRange(
    const std::shared_ptr<executor::TaskExecutor>& executor,
    SemiFuture<void> waitForActiveQueriesToComplete,
    const NamespaceString& nss,
    const UUID& collectionUuid,
    const BSONObj& keyPattern,
    const ChunkRange& range,
    boost::optional<UUID> migrationId,
    int numDocsToRemovePerBatch,
    Seconds delayForActiveQueriesOnSecondariesToComplete,
    Milliseconds delayBetweenBatches);
}  // namespace mongo