// Copyright (C) 2019-2020 Zilliz. All rights reserved.
//
// Licensed 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 <utility>

#include "common/Channel.h"
#include "parquet/arrow/reader.h"

namespace milvus {

struct ArrowTableInfo {
    size_t file_index;       // file index in the file list
    size_t row_group_index;  // row group index in the file, start from 0
    std::shared_ptr<arrow::Table>
        table;  // the arrow table of the row group at row group index in the file index file
};

struct ArrowDataWrapper {
    ArrowDataWrapper() = default;
    ArrowDataWrapper(std::shared_ptr<arrow::RecordBatchReader> reader,
                     std::shared_ptr<parquet::arrow::FileReader> arrow_reader,
                     std::shared_ptr<uint8_t[]> file_data)
        : reader(std::move(reader)),
          arrow_reader(std::move(arrow_reader)),
          file_data(std::move(file_data)) {
    }
    std::shared_ptr<arrow::RecordBatchReader> reader;
    // file reader must outlive the record batch reader
    std::shared_ptr<parquet::arrow::FileReader> arrow_reader;
    // underlying file data memory, must outlive the arrow reader
    std::shared_ptr<uint8_t[]> file_data;
    std::vector<ArrowTableInfo> arrow_tables;
};
using ArrowReaderChannel = Channel<std::shared_ptr<milvus::ArrowDataWrapper>>;

}  // namespace milvus