// 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 <cstddef>

#include <cstdint>

#include <string>

#include <unordered_map>

#include <vector>

#include "common/factory_creator.h"

#include "common/status.h"

#include "format/orc/vorc_reader.h"

#include "format/table/table_schema_change_helper.h"

#include "format/table/transactional_hive_common.h"

namespace doris {

class RuntimeState;

class TFileRangeDesc;

class TFileScanRangeParams;

namespace io {

struct IOContext;

} // namespace io

class Block;

class ShardedKVCache;

class VExprContext;

// TransactionalHiveReader: directly inherits OrcReader (no composition wrapping).

// ACID column expansion/shrinking done via on_before_read_block/on_after_read_block hooks.

// Delete delta reading done via on_after_init_reader hook.

class TransactionalHiveReader final : public OrcReader, public TableSchemaChangeHelper {

    ENABLE_FACTORY_CREATOR(TransactionalHiveReader);

public:

    TransactionalHiveReader(RuntimeProfile* profile, RuntimeState* state,

                            const TFileScanRangeParams& params, const TFileRangeDesc& range,

                            size_t batch_size, const std::string& ctz, io::IOContext* io_ctx,

                            FileMetaCache* meta_cache = nullptr);

    ~TransactionalHiveReader() final = default;

protected:

    // Hook: ACID schema mapping (add transactional columns, map row.* fields)

    Status on_before_init_reader(ReaderInitContext* ctx) override;

    // Hook: read delete delta files

    Status on_after_init_reader(ReaderInitContext* /*ctx*/) override;

    // Hook: expand ACID columns into block before reading

    Status on_before_read_block(Block* block) override;

    // Hook: shrink ACID columns from block after reading

    Status on_after_read_block(Block* block, size_t* read_rows) override;

private:

    struct TransactionalHiveProfile {

        RuntimeProfile::Counter* num_delete_files = nullptr;

        RuntimeProfile::Counter* num_delete_rows = nullptr;

        RuntimeProfile::Counter* delete_files_read_time = nullptr;

    };

    TransactionalHiveProfile _transactional_orc_profile;

    AcidRowIDSet _acid_delete_rows;

    std::vector<std::string> _col_names;

};

} // namespace doris