package sprigx

import (
	`os`
	`os/user`
	`strconv`
	`strings`
)

// osGroupById returns os/user.LookupGroupId. Can accept either an integer or a string.
func osGroupById[T string | int](gid T) (g *user.Group, err error) {

	var gidStr string

	switch t := any(gid).(type) {
	case string:
		gidStr = t
	case int:
		gidStr = strconv.Itoa(t)
	}

	g, err = user.LookupGroupId(gidStr)

	return
}

/*
osFQDN (tries to) return the FQDN of this host.

Currently it just calls os.Hostname() but may be extended to "try harder" in the future.
*/
func osFQDN() (fqdn string, err error) {

	fqdn, err = os.Hostname()

	return
}

/*
osHost returns the system's "host shortname".

Currently it just calls os.Hostname() and takes the first
"host label" (as RFCs refer to it), but it may be extended
in the future.
*/
func osHost() (hostNm string, err error) {

	hostNm, err = os.Hostname()

	if hostNm == "" {
		return
	}
	hostNm = strings.Split(hostNm, ".")[0]

	return
}

// osUserById returns an os/user.LookupId. Can accept either an integer or a string.
func osUserById[T string | int](uid T) (u *user.User, err error) {

	var uidStr string

	switch t := any(uid).(type) {
	case string:
		uidStr = t
	case int:
		uidStr = strconv.Itoa(t)
	}

	u, err = user.LookupId(uidStr)

	return
}