// 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 "common/status.h"

#include "io/fs/file_writer.h"

#include "io/fs/hdfs.h"

#include "io/fs/path.h"

namespace doris {

struct Slice;

namespace io {

class HdfsHandler;

class BlockFileCache;

struct FileCacheAllocatorBuilder;

struct AsyncCloseStatusPack;

class HdfsFileWriter final : public FileWriter {

public:

    // Accepted path format:

    // - fs_name/path_to_file

    // - /path_to_file

    // TODO(plat1ko): Support related path for cloud mode

    static Result<FileWriterPtr> create(Path path, std::shared_ptr<HdfsHandler> handler,

                                        const std::string& fs_name,

                                        const FileWriterOptions* opts = nullptr);

    HdfsFileWriter(Path path, std::shared_ptr<HdfsHandler> handler, hdfsFile hdfs_file,

                   std::string fs_name, const FileWriterOptions* opts = nullptr);

    ~HdfsFileWriter() override;

    Status appendv(const Slice* data, size_t data_cnt) override;

    const Path& path() const override { return _path; }

    size_t bytes_appended() const override { return _bytes_appended; }

    State state() const override { return _state; }

    Status close(bool non_block = false) override;

private:

    Status _close_impl();

    // Flush buffered data into HDFS client and write local file cache if enabled

    // **Notice**: this would clear the underlying buffer

    Status _flush_buffer();

    Status append_hdfs_file(std::string_view content);

    void _write_into_local_file_cache();

    Status _append(std::string_view content);

    void _flush_and_reset_approximate_jni_buffer_size();

    Status _acquire_jni_memory(size_t size);

    Path _path;

    std::shared_ptr<HdfsHandler> _hdfs_handler = nullptr;

    hdfsFile _hdfs_file = nullptr;

    std::string _fs_name;

    size_t _bytes_appended = 0;

    bool _sync_file_data;

    class BatchBuffer {

    public:

        BatchBuffer(size_t capacity);

        size_t append(std::string_view content);

        bool full() const;

        const char* data() const;

        size_t capacity() const;

        size_t size() const;

        void clear();

        std::string_view content() const;

    private:

        std::string _batch_buffer;

    };

    BatchBuffer _batch_buffer;

    size_t _approximate_jni_buffer_size = 0;

    std::unique_ptr<AsyncCloseStatusPack> _async_close_pack;

    // We should make sure that close_impl's return value is consistent

    // So we need add one field to restore the value first time return by calling close_impl

    Status _st;

    State _state {State::OPENED};

};

} // namespace io

} // namespace doris