// 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 <common/types.h>

#include <memory>
#include <unordered_map>

namespace DB
{
class Join;
using JoinPtr = std::shared_ptr<Join>;

class IAST;
using ASTPtr = std::shared_ptr<IAST>;

class Set;
using SetPtr = std::shared_ptr<Set>;

class IBlockInputStream;
using BlockInputStreamPtr = std::shared_ptr<IBlockInputStream>;

class IStorage;
using StoragePtr = std::shared_ptr<IStorage>;

/** Information on what to do when executing a subquery in the [GLOBAL] IN/JOIN section.
  */
struct SubqueryForSet
{
    /// The source is obtained using the InterpreterSelectQuery subquery.
    BlockInputStreamPtr source;

    /// If set, build it from result.
    SetPtr set;
    JoinPtr join;

    /// If set, put the result into the table.
    /// This is a temporary table for transferring to remote servers for distributed query processing.
    StoragePtr table;
};

/// ID of subquery -> what to do with it.
using SubqueriesForSets = std::unordered_map<String, SubqueryForSet>;
} // namespace DB