// 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.h"

#include <glog/logging.h>

#include <ostream>

#include "common/status.h"

#include "core/block/block.h"

#include "core/block/column_with_type_and_name.h"

#include "core/column/column.h"

#include "core/column/column_array.h"

#include "core/column/column_nothing.h"

#include "core/column/column_variant.h"

#include "core/data_type/data_type.h"

#include "core/data_type/data_type_array.h"

#include "core/data_type/data_type_nothing.h"

#include "exprs/function/function_helpers.h"

#include "exprs/vexpr.h"

#include "exprs/vexpr_context.h"

namespace doris {

VExplodeTableFunction::VExplodeTableFunction() {

_fn_name = "vexplode";

}

Status VExplodeTableFunction::_process_init_variant(Block* block, int value_column_idx) {

// explode variant array

auto column_without_nullable = remove_nullable(block->get_by_position(value_column_idx).column);

auto column = column_without_nullable->convert_to_full_column_if_const();

auto variant_column_ptr = IColumn::mutate(std::move(column));

auto& variant_column = assert_cast<ColumnVariant&>(*variant_column_ptr);

variant_column.finalize();

_detail.output_as_variant = true;

_detail.variant_enable_doc_mode = variant_column.enable_doc_mode();

if (!variant_column.is_null_root()) {

_array_column = variant_column.get_root();

// We need to wrap the output nested column within a variant column.

// Otherwise the type is missmatched

const auto* array_type = check_and_get_data_type<DataTypeArray>(

remove_nullable(variant_column.get_root_type()).get());

if (array_type == nullptr) {

return Status::NotSupported("explode not support none array type {}",

variant_column.get_root_type()->get_name());

}

_detail.nested_type = array_type->get_nested_type();

} else {

// null root, use nothing type

auto array_column = ColumnNullable::create(ColumnArray::create(ColumnNothing::create(0)),

ColumnUInt8::create(0));

array_column->insert_many_defaults(variant_column.size());

_array_column = std::move(array_column);

_detail.nested_type = std::make_shared<DataTypeNothing>();

}

return Status::OK();

}

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

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

<< "VExplodeTableFunction only support 1 child but has "

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

int value_column_idx = -1;

RETURN_IF_ERROR(_expr_context->root()->children()[0]->execute(_expr_context.get(), block,

&value_column_idx));

if (block->get_by_position(value_column_idx).type->get_primitive_type() == TYPE_VARIANT) {

RETURN_IF_ERROR(_process_init_variant(block, value_column_idx));

} else {

_array_column =

block->get_by_position(value_column_idx).column->convert_to_full_column_if_const();

}

if (!extract_column_array_info(*_array_column, _detail)) {

return Status::NotSupported("column type {} not supported now",

block->get_by_position(value_column_idx).column->get_name());

}

return Status::OK();

}

bool VExplodeTableFunction::support_block_fast_path() const {

return true;

}

Status VExplodeTableFunction::prepare_block_fast_path(Block* /*block*/, RuntimeState* /*state*/,

BlockFastPathContext* ctx) {

if (!support_block_fast_path()) {

return Status::NotSupported("vexplode doesn't support block fast path in current mode");

}

if (_detail.offsets_ptr == nullptr || _detail.nested_col.get() == nullptr) {

return Status::InternalError("vexplode block fast path not initialized");

}

ctx->array_nullmap_data = _detail.array_nullmap_data;

ctx->offsets_ptr = _detail.offsets_ptr;

ctx->nested_col = _detail.nested_col;

ctx->nested_nullmap_data = _detail.nested_nullmap_data;

return Status::OK();

}

void VExplodeTableFunction::process_row(size_t row_idx) {

DCHECK(row_idx < _array_column->size());

TableFunction::process_row(row_idx);

if (!_detail.array_nullmap_data || !_detail.array_nullmap_data[row_idx]) {

_array_offset = (*_detail.offsets_ptr)[row_idx - 1];

_cur_size = (*_detail.offsets_ptr)[row_idx] - _array_offset;

}

}

void VExplodeTableFunction::process_close() {

_array_column = nullptr;

_detail.reset();

_array_offset = 0;

}

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

size_t pos = _array_offset + _cur_offset;

if (current_empty() || (_detail.nested_nullmap_data && _detail.nested_nullmap_data[pos])) {

column->insert_many_defaults(length);

} else {

if (_is_nullable) {

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

->get_nested_column_ptr()

->insert_many_from(*_detail.nested_col, pos, length);

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

->get_null_map_column_ptr()

->insert_many_defaults(length);

} else {

column->insert_many_from(*_detail.nested_col, pos, length);

}

}

}

int VExplodeTableFunction::get_value(MutableColumnPtr& column, int max_step) {

max_step = std::min(max_step, (int)(_cur_size - _cur_offset));

size_t pos = _array_offset + _cur_offset;

if (current_empty()) {

column->insert_default();

max_step = 1;

} else {

if (_is_nullable) {

auto* nullable_column = assert_cast<ColumnNullable*>(column.get());

auto nested_column = nullable_column->get_nested_column_ptr();

auto* nullmap_column = nullable_column->get_null_map_column_ptr().get();

nested_column->insert_range_from(*_detail.nested_col, pos, max_step);

size_t old_size = nullmap_column->size();

nullmap_column->resize(old_size + max_step);

memcpy(nullmap_column->get_data().data() + old_size,

_detail.nested_nullmap_data + pos * sizeof(UInt8), max_step * sizeof(UInt8));

} else {

column->insert_range_from(*_detail.nested_col, pos, max_step);

}

}

forward(max_step);

return max_step;

}

} // namespace doris