/*
** Zabbix
** Copyright 2001-2024 Zabbix SIA
**
** 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.
**/

package plugin

import (
	"context"
	"errors"

	"github.com/jackc/pgx/v4"
	"golang.zabbix.com/sdk/zbxerr"
)

// versionHandler queries the version of the PostgreSQL server returns string
// response.
func versionHandler(
	ctx context.Context,
	conn PostgresClient,
	_ string, _ map[string]string, _ ...string,
) (any, error) {
	var version string

	row, err := conn.QueryRow(ctx, `SELECT version();`)
	if err != nil {
		return nil, zbxerr.ErrorCannotFetchData.Wrap(err)
	}

	err = row.Scan(&version)
	if err != nil {
		if errors.Is(err, pgx.ErrNoRows) {
			return nil, zbxerr.ErrorEmptyResult.Wrap(err)
		}

		return nil, zbxerr.ErrorCannotFetchData.Wrap(err)
	}

	return version, nil
}