// 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 <butil/macros.h>

#include <cstdint>

#include <string>

#include <type_traits>

#include "common/factory_creator.h"

#include "common/status.h"

#include "olap/rowset/rowset_meta.h"

#include "olap/tablet_schema.h"

#include "vec/common/arena.h"

namespace doris {

class AndBlockColumnPredicate;

class ColumnPredicate;

class DeletePredicatePB;

class TCondition;

// Represent a delete condition.

struct DeleteConditions {

    int64_t filter_version = 0; // The version of this condition

    std::vector<const ColumnPredicate*> column_predicate_vec;

};

// This class is used for checking whether a row should be deleted.

// It is used in the following processes：

// 1. Create and initialize a DeleteHandler object:

//    Status res;

//    DeleteHandler delete_handler;

//    res = delete_handler.init(tablet, condition_version);

// 2. After all rows have been checked, you should release this object by calling:

//    delete_handler.finalize();

//

// NOTE：

//    * In the first step, before calling delete_handler.init(), you should lock the tablet's header file.

class DeleteHandler {

    ENABLE_FACTORY_CREATOR(DeleteHandler);

    // These static method is used to generate delete predicate pb during write or push handler

public:

    // generated DeletePredicatePB by TCondition

    static Status generate_delete_predicate(const TabletSchema& schema,

                                            const std::vector<TCondition>& conditions,

                                            DeletePredicatePB* del_pred);

    static Status convert_to_sub_pred_v2(DeletePredicatePB* delete_pred, TabletSchemaSPtr schema);

    /**

     * Use regular expression to extract 'column_name', 'op' and 'operands'

     *

     * @param condition_str input predicate string in form of `X OP Y`

     * @param condition output param

     * @return OK if matched and extracted correctly otherwise DELETE_INVALID_PARAMETERS

     */

    static Status parse_condition(const std::string& condition_str, TCondition* condition);

private:

    // Validate the condition on the schema.

    static Status check_condition_valid(const TabletSchema& tablet_schema, const TCondition& cond);

    // Check whether the condition value is valid according to its type.

    // 1. For integers(int8,int16,in32,int64,uint8,uint16,uint32,uint64), check whether they are overflow

    // 2. For decimal, check whether precision or scale is overflow

    // 3. For date and datetime, check format and value

    // 4. For char and varchar, check length

    static bool is_condition_value_valid(const TabletColumn& column,

                                         const std::string& condition_op,

                                         const std::string& value_str);

    // extract 'column_name', 'op' and 'operands' to condition

    static Status parse_condition(const DeleteSubPredicatePB& sub_cond, TCondition* condition);

public:

    DeleteHandler() = default;

    ~DeleteHandler();

    // Initialize DeleteHandler, use the delete conditions of this tablet whose version less than or equal to

    // 'version' to fill '_del_conds'.

    // NOTE: You should lock the tablet's header file before calling this function.

    // input:

    //     * schema: tablet's schema, the delete conditions and data rows are in this schema

    //     * version: maximum version

    //     * with_sub_pred_v2: whether to use delete sub predicate v2 (v2 is based on PB and use column uid to specify a column,

    //         v1 is based on condition string, and relies on regex for parse)

    // return:

    //     * Status::Error<DELETE_INVALID_PARAMETERS>(): input parameters are not valid

    //     * Status::Error<MEM_ALLOC_FAILED>(): alloc memory failed

    Status init(TabletSchemaSPtr tablet_schema,

                const std::vector<RowsetMetaSharedPtr>& delete_preds, int64_t version);

    [[nodiscard]] bool empty() const { return _del_conds.empty(); }

    void get_delete_conditions_after_version(

            int64_t version, AndBlockColumnPredicate* and_block_column_predicate_ptr,

            std::unordered_map<int32_t, std::vector<const ColumnPredicate*>>*

                    del_predicates_for_zone_map) const;

private:

    template <typename SubPredType>

        requires(std::is_same_v<SubPredType, DeleteSubPredicatePB> or

                 std::is_same_v<SubPredType, std::string>)

    Status _parse_column_pred(

            TabletSchemaSPtr complete_schema, TabletSchemaSPtr delete_pred_related_schema,

            const ::google::protobuf::RepeatedPtrField<SubPredType>& sub_pred_list,

            DeleteConditions* delete_conditions);

    bool _is_inited = false;

    // DeleteConditions in _del_conds are in 'OR' relationship

    std::vector<DeleteConditions> _del_conds;

    std::unique_ptr<vectorized::Arena> _predicate_arena;

    DISALLOW_COPY_AND_ASSIGN(DeleteHandler);

};

} // namespace doris