zones: calculate Machine.ID on init

Signed-off-by: Alejandro Mery <amery@jpi.io>

pkg/zones/machine.go

@@ -5,7 +5,6 @@ import (
 	"io/fs"
 	"net/netip"
 	"path/filepath"
-	"strconv"
 	"strings"
 	"sync"
 )
@@ -15,7 +14,7 @@ type Machine struct {
 	mu sync.Mutex
 
 	zone *Zone
-	id   int
+	ID   int
 	Name string `toml:"name"`
 
 	PublicAddresses []netip.Addr `toml:"public,omitempty"`
@@ -26,27 +25,6 @@ func (m *Machine) String() string {
 	return m.Name
 }
 
-// ID return the index within the [Zone] associated to this [Machine]
-func (m *Machine) ID() int {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-
-	if m.id == 0 {
-		zoneName := m.zone.Name
-
-		s := m.Name[len(zoneName)+1:]
-
-		id, err := strconv.ParseInt(s, 10, 8)
-		if err != nil {
-			panic(err)
-		}
-
-		m.id = int(id)
-	}
-
-	return m.id
-}
-
 // FullName returns the Name of the machine including domain name
 func (m *Machine) FullName() string {
 	if domain := m.zone.zones.domain; domain != "" {