#pragma once

#include <Parsers/ASTExpressionList.h>
#include <Parsers/IAST.h>
#include <Parsers/MySQL/ASTDeclareColumn.h>
#include <Parsers/MySQL/ASTDeclareIndex.h>

namespace DB
{

namespace ErrorCodes
{
    extern const int NOT_IMPLEMENTED;
}

namespace MySQLParser
{

class ASTAlterCommand : public IAST
{
public:
    enum Type
    {
        ADD_INDEX,
        ADD_COLUMN,

        DROP_INDEX,
        DROP_CHECK,
        DROP_COLUMN,
        DROP_COLUMN_DEFAULT,

        RENAME_INDEX,
        RENAME_COLUMN,
        RENAME_TABLE,

        MODIFY_CHECK,
        MODIFY_COLUMN,
        MODIFY_INDEX_VISIBLE,
        MODIFY_COLUMN_DEFAULT,
        MODIFY_PROPERTIES,

        ORDER_BY,

        NO_TYPE
    };

    Type type = NO_TYPE;

    /// For ADD INDEX
    ASTDeclareIndex * index_decl = nullptr;

    /// For modify default expression
    IAST * default_expression = nullptr;

    /// For ADD COLUMN
    ASTExpressionList * additional_columns = nullptr;
    /// For ORDER BY
    ASTExpressionList * order_by_columns = nullptr;

    bool first = false;
    bool index_visible = false;
    bool not_check_enforced = false;

    String old_name;
    String index_type;
    String index_name;
    String column_name;
    String constraint_name;
    String new_database_name;
    String new_table_name;

    IAST * properties = nullptr;

    ASTPtr clone() const override;

    String getID(char delim) const override { return "AlterCommand" + (delim + std::to_string(static_cast<int>(type))); }

protected:
    void formatImpl(const FormatSettings & /*settings*/, FormatState & /*state*/, FormatStateStacked /*frame*/) const override
    {
        throw Exception(ErrorCodes::NOT_IMPLEMENTED, "Method formatImpl is not supported by MySQLParser::ASTAlterCommand.");
    }

    void forEachPointerToChild(std::function<void(void**)> f) override
    {
        f(reinterpret_cast<void **>(&index_decl));
        f(reinterpret_cast<void **>(&default_expression));
        f(reinterpret_cast<void **>(&additional_columns));
        f(reinterpret_cast<void **>(&order_by_columns));
        f(reinterpret_cast<void **>(&properties));
    }
};

class ParserAlterCommand : public IParserBase
{
protected:
    const char * getName() const override { return "alter command"; }

    bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected) override;
};

}

}