// 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 <string>

#include <utility>

#include <vector>

#include "common/status.h"

#include "io/fs/file_system.h"

#include "io/fs/path.h"

namespace doris::io {

class RemoteFileSystem : public FileSystem {

public:

    RemoteFileSystem(Path&& root_path, std::string&& id, FileSystemType type)

            : FileSystem(std::move(id), type), _root_path(std::move(root_path)) {}

    ~RemoteFileSystem() override = default;

    Status upload(const Path& local_file, const Path& dest_file);

    Status batch_upload(const std::vector<Path>& local_files,

                        const std::vector<Path>& remote_files);

    Status download(const Path& remote_file, const Path& local);

    // the root path of this fs.

    const Path& root_path() const { return _root_path; }

protected:

    Status open_file_impl(const Path& file, FileReaderSPtr* reader,

                          const FileReaderOptions* opts) override;

    /// upload load_file to remote remote_file

    /// local_file should be an absolute path on local filesystem.

    virtual Status upload_impl(const Path& local_file, const Path& remote_file) = 0;

    /// upload all files in load_files to remote_files

    /// path in local_files should be an absolute path on local filesystem.

    /// the size of local_files and remote_files must be equal.

    virtual Status batch_upload_impl(const std::vector<Path>& local_files,

                                     const std::vector<Path>& remote_files) = 0;

    /// download remote_file to local_file

    /// local_file should be an absolute path on local filesystem.

    virtual Status download_impl(const Path& remote_file, const Path& local_file) = 0;

    // The derived class should implement this method.

    // if file_size < 0, the file size should be fetched from file system

    virtual Status open_file_internal(const Path& file, FileReaderSPtr* reader,

                                      const FileReaderOptions& opts) = 0;

    Status absolute_path(const Path& path, Path& abs_path) const override {

        if (path.is_absolute()) {

            abs_path = path;

        } else {

            abs_path = _root_path / path;

        }

        return Status::OK();

    }

    Path _root_path;

};

using RemoteFileSystemSPtr = std::shared_ptr<RemoteFileSystem>;

} // namespace doris::io