/**
 *    Copyright (C) 2022-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 "mongo/db/operation_context.h"

namespace mongo::timeseries {

/**
 * Tracks _id values for time series bucket documents that have been deleted, so that they may be
 * cleared from the BucketCatalog after the deletion has taken place. By default, we do not provide
 * the _id of the deleted document to the OpObserver::onDelete interface. This class decorates the
 * OperationContext in order to provide these values.
 */
class DeletedBuckets {
public:
    static DeletedBuckets& get(OperationContext*);

    /**
     * Track the 'oid' of a bucket that is to be deleted.
     */
    void emplace(const OID& oid);

    /**
     * Apply 'fn' to each bucket that has been deleted, then clear the set of tracked buckets.
     */
    void for_each_once(const std::function<void(const OID&)>& fn);

private:
    stdx::unordered_set<OID> _buckets;
};

}  // namespace mongo::timeseries