// Licensed to the Apache Software Foundation (ASF) under one

// or more contributor license agreements.  See the NOTICE file

// distributed with this work for additional information

// regarding copyright ownership.  The ASF 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.

#pragma once

#include <memory>

#include <mutex>

#include <string>

#include <vector>

#include "cloud/cloud_tablet.h"

#include "common/status.h"

#include "storage/rowset/rowset_fwd.h"

#include "storage/storage_policy.h"

#include "storage/tablet/tablet_fwd.h"

namespace doris {

class CloudStorageEngine;

class RowsetMetaPB;

class MemTrackerLimiter;

// In cloud mode, snapshot only includes tablet metas.

class CloudSnapshotMgr {

public:

    CloudSnapshotMgr(CloudStorageEngine& engine);

    ~CloudSnapshotMgr() = default;

    /**

     * Creates a snapshot for the specified tablet.

     * Behavior:

     * - For restore, convert and upload snapshot.

     * - For backup, not implemented

     *

     * @param storage_resource. Used for set the resource id.

     * @param file_mapping. A map to store file mappings. (source files -> target files).

     * @param is_restore. Whether the snapshot is for a restore job. (default: false).

     * @param slice. For hdr data input, only used for restore job. (default: nullptr).

     * @return status.

     */

    Status make_snapshot(int64_t target_tablet_id, StorageResource& storage_resource,

                         std::unordered_map<std::string, std::string>& file_mapping,

                         bool is_restore = false, const Slice* slice = nullptr);

    /**

     * Releases a snapshot for the specified tablet.

     * Behavior:

     * - Marks the snapshot to final state.

     * - This method will only be called at the last step of completing or canceling

     *   the job, and FE will not care whether the status returned here is successful

     *   or failed. After the status is returned, the entire job will end.

     *

     * @param is_completed. True, indicates the job is completing.

     *                      False, indicates the job is canceling.

     * @return status.

     */

    Status release_snapshot(int64_t tablet_id, bool is_completed);

    /**

     * Commits a snapshot for the specified tablet, only used for restore job.

     * Behavior:

     * - Finalizes the uploaded snapshot and clear local tablet cache.

     *

     * @return status.

     */

    Status commit_snapshot(int64_t tablet_id);

    Status convert_rowsets(TabletMetaPB* out, const TabletMetaPB& in, int64_t tablet_id,

                           CloudTabletSPtr& target_tablet, StorageResource& storage_resource,

                           std::unordered_map<std::string, std::string>& file_mapping);

private:

    Status _create_rowset_meta(RowsetMetaPB* new_rowset_meta_pb, const RowsetMetaPB& source_meta,

                               int64_t target_tablet_id, CloudTabletSPtr& target_tablet,

                               StorageResource& storage_resource, TabletSchemaSPtr tablet_schema,

                               std::unordered_map<std::string, std::string>& file_mapping,

                               std::unordered_map<RowsetId, RowsetId>& rowset_id_mapping);

    Status _rename_index_ids(TabletSchemaPB& schema_pb,

                             const TabletSchemaSPtr& tablet_schema) const;

private:

    CloudStorageEngine& _engine;

    std::atomic<uint64_t> _snapshot_base_id {0};

    std::shared_ptr<MemTrackerLimiter> _mem_tracker;

}; // CloudSnapshotMgr

} // namespace doris