// 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 <functional>

#include <map>

#include <memory>

#include <string>

#include <vector>

#include "format_v2/file_reader.h"

#include "format_v2/table_reader.h"

namespace doris {

class ScrollParser;

class SlotDescriptor;

} // namespace doris

namespace doris::format::es {

// The transport boundary allows reader tests to use real ES responses without a running server.

class EsScrollStream {

public:

    virtual ~EsScrollStream() = default;

    virtual Status open() = 0;

    virtual Status next(bool* eof, std::unique_ptr<ScrollParser>& parser) = 0;

    virtual Status close() = 0;

};

using EsScrollStreamFactory = std::function<std::unique_ptr<EsScrollStream>(

        const std::string&, const std::map<std::string, std::string>&, bool)>;

class EsFileReader final : public FileReader {

public:

    EsFileReader(std::shared_ptr<io::FileSystemProperties>& system_properties,

                 std::unique_ptr<io::FileDescription>& file_description,

                 std::shared_ptr<io::IOContext> io_ctx, RuntimeProfile* profile,

                 TFileRangeDesc range, const TFileScanRangeParams& params,

                 std::vector<SlotDescriptor*> file_slot_descs,

                 EsScrollStreamFactory stream_factory = {});

    ~EsFileReader() override;

    Status init(RuntimeState* state) override;

    Status get_schema(std::vector<ColumnDefinition>* schema) const override;

    std::unique_ptr<TableColumnMapper> create_column_mapper(

            TableColumnMapperOptions options) const override;

    void set_batch_size(size_t batch_size) override;

    Status open(std::shared_ptr<FileScanRequest> request) override;

    Status get_block(Block* block, size_t* rows, bool* eof) override;

    Status close() override;

private:

    void _init_profile() override;

    Status _open_stream();

    Status _next_page();

    Status _read_block(Block* block, size_t* rows, bool* eof);

    const TFileRangeDesc _range;

    const TFileScanRangeParams& _params;

    const std::vector<SlotDescriptor*> _file_slots;

    EsScrollStreamFactory _stream_factory;

    RuntimeState* _state = nullptr;

    size_t _batch_size = 1024;

    std::unique_ptr<EsScrollStream> _stream;

    std::unique_ptr<ScrollParser> _parser;

    std::vector<SlotDescriptor*> _read_slots;

    std::vector<size_t> _read_positions;

    std::map<std::string, std::string> _docvalue_context;

    size_t _page_rows_remaining = 0;

    bool _source_eof = false;

    RuntimeProfile::Counter* _total_time = nullptr;

    RuntimeProfile::Counter* _read_time = nullptr;

    RuntimeProfile::Counter* _materialize_time = nullptr;

    RuntimeProfile::Counter* _filter_time = nullptr;

    RuntimeProfile::Counter* _io_time = nullptr;

    RuntimeProfile::Counter* _batches_read = nullptr;

    RuntimeProfile::Counter* _rows_read = nullptr;

};

class EsReader final : public TableReader {

public:

    explicit EsReader(EsScrollStreamFactory stream_factory = {});

    Status init(TableReadOptions&& options) override;

    Status prepare_split(const SplitReadOptions& options) override;

protected:

    Status create_file_reader(std::unique_ptr<FileReader>* reader) override;

private:

    EsScrollStreamFactory _stream_factory;

};

} // namespace doris::format::es