// 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 <utility>

#include "format_v2/table_reader.h"

namespace doris {

struct DeleteFileDesc;

}

namespace doris::format::paimon {

class PaimonReader final : public format::TableReader {

public:

    ENABLE_FACTORY_CREATOR(PaimonReader);

    ~PaimonReader() final = default;

    Status prepare_split(const format::SplitReadOptions& options) override;

#ifdef BE_TEST

    void TEST_set_scan_params(TFileScanRangeParams* params) { _scan_params = params; }

    void TEST_set_projected_columns(std::vector<format::ColumnDefinition> columns) {

        _projected_columns = std::move(columns);

    }

    void TEST_set_format(format::FileFormat format) { _format = format; }

    format::TableColumnMappingMode TEST_mapping_mode() const { return mapping_mode(); }

    Status TEST_annotate_file_schema(std::vector<format::ColumnDefinition>* file_schema) {

        return annotate_file_schema(file_schema);

    }

    Status TEST_customize_file_scan_request(format::FileScanRequest* request) {

        return customize_file_scan_request(request);

    }

    Status TEST_parse_deletion_vector_file(const TTableFormatFileDesc& t_desc, DeleteFileDesc* desc,

                                           bool* has_delete_file) {

        return _parse_deletion_vector_file(t_desc, desc, has_delete_file);

    }

#endif

protected:

    format::TableColumnMappingMode mapping_mode() const override;

    Status annotate_file_schema(std::vector<format::ColumnDefinition>* file_schema) override;

    Status customize_file_scan_request(format::FileScanRequest* file_request) override;

    Status _parse_deletion_vector_file(const TTableFormatFileDesc& t_desc, DeleteFileDesc* desc,

                                       bool* has_delete_file) override;

private:

    int64_t _split_schema_id = -1;

    std::vector<format::LocalColumnIndex> _variant_schema_overrides;

};

// Paimon scans can contain both native data-file splits and serialized JNI splits in the same

// SplitSource. FileScannerV2 owns one table reader for the scanner lifetime, so this reader keeps

// native and JNI child readers internally and dispatches each split to the matching child reader.

class PaimonHybridReader final : public format::TableReader {

public:

    ~PaimonHybridReader() override = default;

    Status init(format::TableReadOptions&& options) override;

    Status prepare_split(const format::SplitReadOptions& options) override;

    Status refresh_conjuncts(VExprContextSPtrs conjuncts) override;

    Status get_block(Block* block, bool* eos) override;

    bool current_split_pruned() const override;

    bool current_split_uses_metadata_count() const override;

    Status abort_split() override;

    Status close() override;

    void set_batch_size(size_t batch_size) override;

    int64_t condition_cache_hit_count() const override;

#ifdef BE_TEST

    static bool TEST_is_jni_split(const TFileRangeDesc& range) { return _is_jni_split(range); }

    static Status TEST_to_file_format(const TFileRangeDesc& range,

                                      format::FileFormat* file_format) {

        return _to_file_format(range, file_format);

    }

    void TEST_install_batch_size_children() {

        _native_reader = std::make_unique<format::TableReader>();

        _jni_reader = std::make_unique<format::TableReader>();

    }

    std::pair<size_t, size_t> TEST_child_batch_sizes() const {

        return {_native_reader->TEST_batch_size(), _jni_reader->TEST_batch_size()};

    }

    void TEST_set_child_condition_cache_hits(int64_t native_hits, int64_t jni_hits) {

        _native_reader->TEST_set_condition_cache_hit_count(native_hits);

        _jni_reader->TEST_set_condition_cache_hit_count(jni_hits);

    }

    void TEST_set_child_reader_factories(

            std::function<std::unique_ptr<format::TableReader>()> native_factory,

            std::function<std::unique_ptr<format::TableReader>()> jni_factory) {

        _test_native_reader_factory = std::move(native_factory);

        _test_jni_reader_factory = std::move(jni_factory);

    }

#endif

private:

    Status _ensure_current_split_reader(const format::SplitReadOptions& options);

    Status _init_child_reader(format::TableReader* reader, format::FileFormat file_format);

    Status _clone_conjuncts(VExprContextSPtrs* conjuncts) const;

    static bool _is_jni_split(const TFileRangeDesc& range);

    static Status _to_file_format(const TFileRangeDesc& range, format::FileFormat* file_format);

    std::unique_ptr<format::TableReader> _native_reader; // handle parquet/orc native splits

    std::unique_ptr<format::TableReader> _jni_reader;    // handle serialized JNI splits

    format::TableReader* _current_split_reader = nullptr;

#ifdef BE_TEST

    std::function<std::unique_ptr<format::TableReader>()> _test_native_reader_factory;

    std::function<std::unique_ptr<format::TableReader>()> _test_jni_reader_factory;

#endif

};

} // namespace doris::format::paimon