refactor: remove group & fleet

internal/controller/ship_group.go

@@ -68,22 +68,18 @@ func (c *Cache) ShipGroupDestroyItem(i int) {
 	sg.Number -= 1
 }
 
-func (c *Cache) DeleteShipGroup(i int) {
-	c.validateShipGroupIndex(i)
-	c.unsafeDeleteShipGroup(i)
-}
-
 func (c *Cache) DeleteKilledShipGroups() {
 	keepFleet := make(map[uuid.UUID]bool, len(c.g.Fleets))
-	for i := len(c.g.ShipGroups) - 1; i >= 0; i-- {
-		if c.g.ShipGroups[i].FleetID != nil {
-			id := *c.g.ShipGroups[i].FleetID
-			keepFleet[id] = keepFleet[id] || c.g.ShipGroups[i].Number > 0
+	for sgi := len(c.g.ShipGroups) - 1; sgi >= 0; sgi-- {
+		if c.g.ShipGroups[sgi].FleetID != nil {
+			id := *c.g.ShipGroups[sgi].FleetID
+			keepFleet[id] = keepFleet[id] || c.g.ShipGroups[sgi].Number > 0
 		}
-		if c.g.ShipGroups[i].Number == 0 {
-			c.unsafeDeleteShipGroup(i)
+		if c.g.ShipGroups[sgi].Number == 0 {
+			c.g.ShipGroups = append(c.g.ShipGroups[:sgi], c.g.ShipGroups[sgi+1:]...)
 		}
 	}
+	c.invalidateShipGroupCache()
 	for id, keep := range keepFleet {
 		if keep {
 			continue
@@ -122,7 +118,7 @@ func (c *Cache) shipGroupMerge(ri int) {
 	for i := 0; i < len(raceGroups)-1; i++ {
 		for j := len(raceGroups) - 1; j > i; j-- {
 			if raceGroups[i].Equal(raceGroups[j]) {
-				raceGroups[i].ID = raceGroups[j].ID
+				raceGroups[i].ID = raceGroups[j].ID // resulting group will have latest ID
 				raceGroups[i].Number += raceGroups[j].Number
 				raceGroups = append(raceGroups[:j], raceGroups[j+1:]...)
 			}
@@ -141,8 +137,8 @@ func (c *Cache) shipGroupMerge(ri int) {
 
 	slices.Sort(toDelete)
 	slices.Reverse(toDelete)
-	for _, idx := range toDelete {
-		c.unsafeDeleteShipGroup(idx)
+	for _, sgi := range toDelete {
+		c.unsafeDeleteShipGroup(sgi)
 	}
 
 	for i := range raceGroups {