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// to you under the Apache License, Version 2.0 (the

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//

//   http://www.apache.org/licenses/LICENSE-2.0

//

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#include "format_v2/expr/delete_predicate.h"

#include <fmt/format.h>

#include <gen_cpp/Exprs_types.h>

#include <glog/logging.h>

#include <algorithm>

#include <cstddef>

#include <ostream>

#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"

namespace doris::format {

DeletePredicate::DeletePredicate(const std::vector<int64_t>& deleted_rows)

        : VExpr(), _deleted_rows(deleted_rows) {

    _node_type = TExprNodeType::PREDICATE;

    _opcode = TExprOpcode::DELETE;

    _data_type = std::make_shared<DataTypeBool>();

}

Status DeletePredicate::prepare(RuntimeState* state, const RowDescriptor& desc,

                                VExprContext* context) {

    RETURN_IF_ERROR_OR_PREPARED(VExpr::prepare(state, desc, context));

    _expr_name = "DeletePredicate";

    _prepare_finished = true;

    return Status::OK();

}

Status DeletePredicate::open(RuntimeState* state, VExprContext* context,

                             FunctionContext::FunctionStateScope scope) {

    DCHECK(_prepare_finished);

    RETURN_IF_ERROR_OR_PREPARED(VExpr::open(state, context, scope));

    _open_finished = true;

    return Status::OK();

}

void DeletePredicate::close(VExprContext* context, FunctionContext::FunctionStateScope scope) {

    VExpr::close(context, scope);

}

/**

 * DeletePredicate is derived from 2 cases:

 * 1. All row IDs indicates deleted rows. (e.g. Delete rows with row_id in (1, 2, 3))

 * 2. Bit vector indicates whether each row is deleted or not. (e.g. Bit vector[0,1,0,0,1] indicates row 1 and row 4 are deleted)

 *

 * So DeletePredicate should have exactly 1 child expr, which is the slot of row id.

 * Row IDs should be generated by file reader as a virtual column in `block`.

 **/

Status DeletePredicate::execute(VExprContext* context, Block* block, int* result_column_id) const {

    if (_children.size() != 1) {

        return Status::InternalError(fmt::format(

                "DeletePredicate should have exactly 1 child expr, but got {}", _children.size()));

    }

    int slot = -1;

    RETURN_IF_ERROR(_children[0]->execute(context, block, &slot));

    if (slot < 0 || static_cast<size_t>(slot) >= block->columns()) {

        return Status::InternalError(

                "DeletePredicate row id child returned invalid column id {}, block has {} columns",

                slot, block->columns());

    }

    const auto& row_ids =

            assert_cast<const ColumnInt64&>(*block->get_by_position(slot).column).get_data();

    const auto count = row_ids.size();

    auto res_col = ColumnBool::create(count, 0);

    if (_deleted_rows.empty()) {

        block->insert({std::move(res_col), std::make_shared<DataTypeBool>(), expr_name()});

        *result_column_id = static_cast<int>(block->get_columns().size() - 1);

        return Status::OK();

    }

    if (count == 0) {

        block->insert({std::move(res_col), std::make_shared<DataTypeBool>(), expr_name()});

        *result_column_id = static_cast<int>(block->get_columns().size() - 1);

        return Status::OK();

    }

    const int64_t* delete_rows = _deleted_rows.data();

    const int64_t* delete_rows_end = delete_rows + _deleted_rows.size();

    const int64_t* start_pos = std::lower_bound(delete_rows, delete_rows_end, row_ids[0]);

    int64_t start_index = start_pos - delete_rows;

    const int64_t* end_pos = std::upper_bound(start_pos, delete_rows_end, row_ids[count - 1]);

    const int64_t end_index = end_pos - delete_rows;

    while (start_index < end_index) {

        int64_t delete_row = delete_rows[start_index];

        if (const auto it = std::ranges::lower_bound(row_ids, delete_row);

            it != row_ids.end() && *it == delete_row) {

            const size_t index = it - row_ids.begin();

            res_col->get_data()[index] = true;

        }

        ++start_index;

    }

    block->insert({std::move(res_col), std::make_shared<DataTypeBool>(), expr_name()});

    *result_column_id = static_cast<int>(block->get_columns().size() - 1);

    return Status::OK();

}

std::string DeletePredicate::debug_string() const {

    return _expr_name;

}

} // namespace doris::format