// 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 <functional>

#include <string>

#include "common/object_pool.h"

#include "common/status.h"

#include "core/block/column_with_type_and_name.h"

#include "core/data_type/data_type.h"

#include "core/data_type/define_primitive_type.h"

#include "exprs/aggregate/aggregate_function.h"

#include "exprs/function_context.h"

#include "exprs/vexpr.h"

namespace doris {

class RowDescriptor;

class RuntimeState;

class TExprNode;

class Block;

class VExprContext;

} // namespace doris

namespace doris {

class VCastExpr : public VExpr {

    ENABLE_FACTORY_CREATOR(VCastExpr);

public:

#ifdef BE_TEST

    VCastExpr() = default;

#endif

    VCastExpr(const TExprNode& node)

            : VExpr(node), _is_strict_cast(node.__isset.is_strict_cast && node.is_strict_cast) {}

    ~VCastExpr() override = default;

    Status execute_column_impl(VExprContext* context, const Block* block, const Selector* selector,

                               size_t count, ColumnPtr& result_column) const override;

    Status prepare(RuntimeState* state, const RowDescriptor& desc, VExprContext* context) override;

    Status open(RuntimeState* state, VExprContext* context,

                FunctionContext::FunctionStateScope scope) override;

    void close(VExprContext* context, FunctionContext::FunctionStateScope scope) override;

    const std::string& expr_name() const override;

    std::string debug_string() const override;

    const DataTypePtr& get_target_type() const;

    bool is_safe_to_execute_on_selected_rows() const override { return false; }

    virtual std::string cast_name() const { return "CAST"; }

    Status clone_node(VExprSPtr* cloned_expr) const override {

        DORIS_CHECK(cloned_expr != nullptr);

        *cloned_expr = VCastExpr::create_shared(clone_texpr_node());

        return Status::OK();

    }

    uint64_t get_digest(uint64_t seed) const override {

        auto res = VExpr::get_digest(seed);

        if (res) {

            res = HashUtil::hash64(_target_data_type_name.data(), _target_data_type_name.size(),

                                   res);

            return HashUtil::hash64(&_is_strict_cast, sizeof(_is_strict_cast), res);

        }

        return 0;

    }

protected:

    using CastExecutor =

            std::function<Status(RuntimeState*, const ColumnWithTypeAndName&,

                                 ColumnWithTypeAndName&, size_t, const NullMap::value_type*)>;

    Status execute_cast(RuntimeState* state, const ColumnWithTypeAndName& source,

                        const DataTypePtr& result_type, size_t rows,

                        ColumnPtr& result_column) const;

    CastExecutor _cast_executor;

    std::string _expr_name;

    RuntimeState* _runtime_state = nullptr;

private:

    DataTypePtr _target_data_type;

    std::string _target_data_type_name;

    bool _is_strict_cast = false;

};

class TryCastExpr final : public VCastExpr {

    ENABLE_FACTORY_CREATOR(TryCastExpr);

public:

#ifdef BE_TEST

    TryCastExpr() = default;

#endif

    TryCastExpr(const TExprNode& node)

            : VCastExpr(node), _original_cast_return_is_nullable(node.is_cast_nullable) {}

    Status execute_column_impl(VExprContext* context, const Block* block, const Selector* selector,

                               size_t count, ColumnPtr& result_column) const override;

    ~TryCastExpr() override = default;

    std::string cast_name() const override { return "TRY CAST"; }

    bool is_safe_to_execute_on_selected_rows() const override {

        return VExpr::is_safe_to_execute_on_selected_rows();

    }

    Status clone_node(VExprSPtr* cloned_expr) const override {

        DORIS_CHECK(cloned_expr != nullptr);

        auto node = clone_texpr_node();

        node.__set_is_cast_nullable(_original_cast_return_is_nullable);

        *cloned_expr = TryCastExpr::create_shared(node);

        return Status::OK();

    }

private:

    DataTypePtr original_cast_return_type() const;

    Status single_row_execute(VExprContext* context, const ColumnWithTypeAndName& input_info,

                              ColumnPtr& return_column) const;

    //Try_cast always returns nullable,

    // but we also need the information of whether the return value of the original cast is nullable.

    bool _original_cast_return_is_nullable = false;

};

} // namespace doris