// Copyright 2023 PingCAP, Inc.
//
// Licensed 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 <Columns/IColumnDummy.h>


namespace DB
{
class Set;
using ConstSetPtr = std::shared_ptr<const Set>;


/** A column containing multiple values in the `IN` section.
  * Behaves like a constant-column (because the set is one, not its own for each line).
  * This column has a nonstandard value, so it can not be obtained via a normal interface.
  */
class ColumnSet final : public COWPtrHelper<IColumnDummy, ColumnSet>
{
private:
    friend class COWPtrHelper<IColumnDummy, ColumnSet>;

    ColumnSet(size_t s_, const ConstSetPtr & data_)
        : data(data_)
    {
        s = s_;
    }
    ColumnSet(const ColumnSet &) = default;

public:
    const char * getFamilyName() const override { return "Set"; }
    MutableColumnPtr cloneDummy(size_t s_) const override { return ColumnSet::create(s_, data); }

    ConstSetPtr getData() const { return data; }

private:
    ConstSetPtr data;
};

} // namespace DB