// Licensed to the Apache Software Foundation (ASF) under one

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// 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.

#include <fmt/format.h>

#include <glog/logging.h>

#include <stddef.h>

#include <memory>

#include <ostream>

#include <string>

#include <utility>

#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/column/column.h"

#include "core/column/column_vector.h"

#include "core/data_type/data_type.h"

#include "core/types.h"

#include "exprs/aggregate/aggregate_function.h"

#include "exprs/function/array/function_array_utils.h"

#include "exprs/function/function.h"

#include "exprs/function/simple_function_factory.h"

namespace doris {

class FunctionContext;

} // namespace doris

namespace doris {

class FunctionArrayFilter : public IFunction {

public:

static constexpr auto name = "array_filter";

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

/// Get function name.

String get_name() const override { return name; }

bool is_variadic() const override { return false; }

size_t get_number_of_arguments() const override { return 2; }

DataTypePtr get_return_type_impl(const DataTypes& arguments) const override {

DCHECK(arguments[0]->get_primitive_type() == TYPE_ARRAY)

<< "First argument for function: " << name

<< " should be DataTypeArray but it has type " << arguments[0]->get_name() << ".";

return arguments[0];

}

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

uint32_t result, size_t input_rows_count) const override {

//TODO: maybe need optimize not convert

auto first_column =

block.get_by_position(arguments[0]).column->convert_to_full_column_if_const();

auto second_column =

block.get_by_position(arguments[1]).column->convert_to_full_column_if_const();

const ColumnArray& first_col_array = assert_cast<const ColumnArray&>(*first_column);

const auto& first_off_data = first_col_array.get_offsets_column().get_data();

const auto& first_nested_nullable_column =

assert_cast<const ColumnNullable&>(*first_col_array.get_data_ptr());

const ColumnArray& second_col_array = assert_cast<const ColumnArray&>(*second_column);

const auto& second_off_data = second_col_array.get_offsets_column().get_data();

const auto& second_nested_null_map_data =

assert_cast<const ColumnNullable&>(*second_col_array.get_data_ptr())

.get_null_map_column()

.get_data();

const auto& second_nested_column =

assert_cast<const ColumnNullable&>(*second_col_array.get_data_ptr())

.get_nested_column();

const auto& second_nested_data =

assert_cast<const ColumnUInt8&>(second_nested_column).get_data();

auto result_data_column = first_nested_nullable_column.clone_empty();

auto result_offset_column = ColumnArray::ColumnOffsets::create();

auto& result_offset_data = result_offset_column->get_data();

IColumn::Selector selector;

selector.reserve(first_off_data.size());

result_offset_data.reserve(input_rows_count);

for (size_t row = 0; row < input_rows_count; ++row) {

unsigned long count = 0;

auto first_offset_start = first_off_data[row - 1];

auto first_offset_end = first_off_data[row];

auto second_offset_start = second_off_data[row - 1];

auto second_offset_end = second_off_data[row];

auto move_off = second_offset_start;

for (auto off = first_offset_start;

off < first_offset_end && move_off < second_offset_end; // not out range

++off) {

if (second_nested_null_map_data[move_off] == 0 && // not null

second_nested_data[move_off] == 1) { // not 0

count++;

selector.push_back(off);

}

move_off++;

}

result_offset_data.push_back(count + result_offset_data.back());

}

first_nested_nullable_column.append_data_by_selector(result_data_column, selector);

auto res_column =

ColumnArray::create(std::move(result_data_column), std::move(result_offset_column));

block.replace_by_position(result, std::move(res_column));

return Status::OK();

}

};

void register_function_array_filter_function(SimpleFunctionFactory& factory) {

factory.register_function<FunctionArrayFilter>();

}

} // namespace doris