#include <Parsers/ParserCreateFunctionQuery.h>

#include <Parsers/ASTCreateFunctionQuery.h>
#include <Parsers/ASTExpressionList.h>
#include <Parsers/ASTIdentifier.h>
#include <Parsers/CommonParsers.h>
#include <Parsers/ExpressionElementParsers.h>
#include <Parsers/ExpressionListParsers.h>


namespace DB
{

bool ParserCreateFunctionQuery::parseImpl(IParser::Pos & pos, ASTPtr & node, Expected & expected)
{
    ParserKeyword s_create(Keyword::CREATE);
    ParserKeyword s_function(Keyword::FUNCTION);
    ParserKeyword s_or_replace(Keyword::OR_REPLACE);
    ParserKeyword s_if_not_exists(Keyword::IF_NOT_EXISTS);
    ParserKeyword s_on(Keyword::ON);
    ParserIdentifier function_name_p;
    ParserKeyword s_as(Keyword::AS);
    ParserExpression lambda_p;

    ASTPtr function_name;
    ASTPtr function_core;

    String cluster_str;
    bool or_replace = false;
    bool if_not_exists = false;

    if (!s_create.ignore(pos, expected))
        return false;

    if (s_or_replace.ignore(pos, expected))
        or_replace = true;

    if (!s_function.ignore(pos, expected))
        return false;

    if (!or_replace && s_if_not_exists.ignore(pos, expected))
        if_not_exists = true;

    if (!function_name_p.parse(pos, function_name, expected))
        return false;

    if (s_on.ignore(pos, expected))
    {
        if (!ASTQueryWithOnCluster::parse(pos, cluster_str, expected))
            return false;
    }

    if (!s_as.ignore(pos, expected))
        return false;

    if (!lambda_p.parse(pos, function_core, expected))
        return false;

    auto create_function_query = std::make_shared<ASTCreateFunctionQuery>();
    node = create_function_query;

    create_function_query->function_name = function_name;
    create_function_query->children.push_back(function_name);

    create_function_query->function_core = function_core;
    create_function_query->children.push_back(function_core);

    create_function_query->or_replace = or_replace;
    create_function_query->if_not_exists = if_not_exists;
    create_function_query->cluster = std::move(cluster_str);

    return true;
}

}