cluster: pre-compute Zone's primary region

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

pkg/cluster/regions.go

@@ -102,6 +102,7 @@ func (m *Cluster) initRegions(_ *ScanOptions) error {
 
 	m.sortRegions()
 	m.scanRegionID()
+	m.computeZonesRegion()
 	return nil
 }
 
@@ -277,6 +278,35 @@ func (m *Cluster) scanRegionID() {
 	}
 }
 
+func (m *Cluster) computeZonesRegion() {
+	fn := func(r *Region, z *Zone) {
+		if z.region != nil {
+			m.error(nil).
+				WithField("zone", z.Name).
+				WithField("region", []string{
+					z.region.Name,
+					r.Name,
+				}).
+				Print("zone in two regions")
+		} else {
+			z.region = r
+		}
+	}
+
+	m.ForEachRegion(func(r *Region) bool {
+		var term bool
+
+		if r.IsPrimary() {
+			r.ForEachZone(func(z *Zone) bool {
+				fn(r, z)
+				return term
+			})
+		}
+
+		return term
+	})
+}
+
 func (m *Cluster) getRegion(name string) (*Region, bool) {
 	for i := range m.Regions {
 		r := &m.Regions[i]