// 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.

#include "exprs/table_function/vexplode_numbers.h"

#include <glog/logging.h>

#include <ostream>

#include "common/status.h"

#include "core/assert_cast.h"

#include "core/block/block.h"

#include "core/block/column_with_type_and_name.h"

#include "core/column/column.h"

#include "core/column/column_const.h"

#include "core/column/column_nullable.h"

#include "core/string_ref.h"

#include "exprs/vexpr.h"

#include "exprs/vexpr_context.h"

#include "runtime/runtime_state.h"

namespace doris {

VExplodeNumbersTableFunction::VExplodeNumbersTableFunction() {

    _fn_name = "vexplode_numbers";

}

Status VExplodeNumbersTableFunction::process_init(Block* block, RuntimeState* state) {

    CHECK(_expr_context->root()->children().size() == 1)

            << "VExplodeNumbersTableFunction must be have 1 children but have "

            << _expr_context->root()->children().size();

    RETURN_IF_ERROR(_expr_context->root()->children()[0]->execute_column(

            _expr_context.get(), block, nullptr, block->rows(), _value_column));

    if (is_column_const(*_value_column)) {

        _cur_size = 0;

        // the argument columns -> Int32

        const auto& column_nested =

                assert_cast<const ColumnConst&>(*_value_column).get_data_column_ptr();

        if (column_nested->is_nullable()) {

            if (!column_nested->is_null_at(0)) {

                _cur_size = assert_cast<const ColumnInt32*>(

                                    assert_cast<const ColumnNullable*>(column_nested.get())

                                            ->get_nested_column_ptr()

                                            .get())

                                    ->get_element(0);

            }

        } else {

            _cur_size = assert_cast<const ColumnInt32*>(column_nested.get())->get_element(0);

        }

        ((ColumnInt32*)_elements_column.get())->clear();

        //_cur_size may be a negative number

        _cur_size = std::max(static_cast<int64_t>(0L), _cur_size);

        if (_cur_size &&

            _cur_size <= state->batch_size()) { // avoid elements_column too big or empty

            _is_const = true;                   // use const optimize

            for (int i = 0; i < _cur_size; i++) {

                ((ColumnInt32*)_elements_column.get())->insert_value(i);

            }

        }

    }

    return Status::OK();

}

void VExplodeNumbersTableFunction::process_row(size_t row_idx) {

    TableFunction::process_row(row_idx);

    if (_is_const) {

        return;

    }

    StringRef value = _value_column->get_data_at(row_idx);

    if (value.data != nullptr) {

        _cur_size = std::max(0, *reinterpret_cast<const int*>(value.data));

    }

}

void VExplodeNumbersTableFunction::process_close() {

    _value_column = nullptr;

}

void VExplodeNumbersTableFunction::get_same_many_values(MutableColumnPtr& column, int length) {

    if (current_empty()) {

        column->insert_many_defaults(length);

    } else {

        // for explode numbers, the argument is int32. so cast is safe.

        if (_is_nullable) {

            assert_cast<ColumnInt32*>(

                    assert_cast<ColumnNullable*>(column.get())->get_nested_column_ptr().get())

                    ->insert_many_vals(static_cast<int32_t>(_cur_offset), length);

            assert_cast<ColumnUInt8*>(

                    assert_cast<ColumnNullable*>(column.get())->get_null_map_column_ptr().get())

                    ->insert_many_defaults(length);

        } else {

            assert_cast<ColumnInt32*>(column.get())

                    ->insert_many_vals(static_cast<int32_t>(_cur_offset), length);

        }

    }

}

} // namespace doris