// 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 <glog/logging.h>

#include <stddef.h>

#include <algorithm>

#include <boost/iterator/iterator_facade.hpp>

#include <memory>

#include "common/status.h"

#include "core/block/block.h"

#include "core/block/column_numbers.h"

#include "core/block/column_with_type_and_name.h"

#include "core/block/columns_with_type_and_name.h"

#include "core/column/column.h"

#include "core/column/column_nullable.h"

#include "core/data_type/data_type.h"

#include "core/data_type/data_type_number.h"

#include "core/types.h"

#include "exprs/function/function.h"

namespace doris {

class FunctionContext;

} // namespace doris

namespace doris {

class FunctionGroupingBase : public IFunction {

public:

    size_t get_number_of_arguments() const override { return 1; }

    bool use_default_implementation_for_nulls() const override { return false; }

    DataTypePtr get_return_type_impl(const ColumnsWithTypeAndName& arguments) const override {

        return std::make_shared<DataTypeInt64>();

    }

    Status execute_impl(FunctionContext* context, Block& block, const ColumnNumbers& arguments,

                        uint32_t result, size_t input_rows_count) const override {

        const ColumnWithTypeAndName& src_column = block.get_by_position(arguments[0]);

        DCHECK(src_column.column->size() == input_rows_count);

        // result of functions grouping and grouping_id is always not nullable,

        // but outer join will convert the column to nullable when necessary,

        // so need to remove nullable here when functions grouping and grouping_id are executed

        block.get_by_position(result).column = remove_nullable(src_column.column);

        return Status::OK();

    }

};

class FunctionGrouping : public FunctionGroupingBase {

public:

    static constexpr auto name = "grouping";

    static FunctionPtr create() { return std::make_shared<FunctionGrouping>(); }

    String get_name() const override { return name; }

};

class FunctionGroupingId : public FunctionGroupingBase {

public:

    static constexpr auto name = "grouping_id";

    static FunctionPtr create() { return std::make_shared<FunctionGroupingId>(); }

    String get_name() const override { return name; }

};

} // namespace doris