Implement unbreakable item

server/internal/nbtconv/read.go

@@ -152,6 +152,7 @@ func MapItem(x map[string]any, k string) item.Stack {
 		readEnchantments(tag, &s)
 		readDisplay(tag, &s)
 		readDragonflyData(tag, &s)
+		readUnbreakable(tag, &s)
 		return s
 	}
 	return item.Stack{}
@@ -176,6 +177,7 @@ func Item(data map[string]any, s *item.Stack) item.Stack {
 	readDisplay(tag, s)
 	readDragonflyData(tag, s)
 	readEnchantments(tag, s)
+	readUnbreakable(tag, s)
 	return *s
 }
 
@@ -281,3 +283,9 @@ func readDragonflyData(m map[string]any, s *item.Stack) {
 		}
 	}
 }
+
+// readDamage reads the unbreakable value stored in the NBT with the Unbreakable tag and saves it to the item.Stack
+// passed.
+func readUnbreakable(m map[string]any, s *item.Stack) {
+	*s = s.WithUnbreakable(Bool(m, "Unbreakable"))
+}

server/internal/nbtconv/write.go

@@ -22,6 +22,7 @@ func WriteItem(s item.Stack, disk bool) map[string]any {
 	writeDisplay(tag, s)
 	writeDragonflyData(tag, s)
 	writeEnchantments(tag, s)
+	writeUnbreakable(tag, s)
 
 	data := make(map[string]any)
 	if disk {
@@ -146,3 +147,10 @@ func writeAnvilCost(m map[string]any, s item.Stack) {
 		m["RepairCost"] = int32(cost)
 	}
 }
+
+// writeUnbreakable writes the unbreakable tag to an item stack if it is unbreakable.
+func writeUnbreakable(m map[string]any, s item.Stack) {
+	if s.Unbreakable() {
+		m["Unbreakable"] = byte(1)
+	}
+}

server/item/stack.go

@@ -23,7 +23,8 @@ type Stack struct {
 	customName string
 	lore       []string
 
-	damage int
+	damage      int
+	unbreakable bool
 
 	anvilCost int
 
@@ -98,7 +99,7 @@ func (s Stack) MaxDurability() int {
 // get the maximum durability.
 func (s Stack) Damage(d int) Stack {
 	durable, ok := s.Item().(Durable)
-	if !ok {
+	if !ok || s.unbreakable {
 		// Not a durable item.
 		return s
 	}
@@ -146,6 +147,21 @@ func (s Stack) WithDurability(d int) Stack {
 	return s
 }
 
+// Unbreakable checks if the item stack is unbreakable.
+func (s Stack) Unbreakable() bool {
+	return s.unbreakable
+}
+
+// WithUnbreakable returns a copy of the Stack with the unbreakable tag set to the value passed. If the item
+// does not implement the Durable interface, the original stack is returned.
+func (s Stack) WithUnbreakable(u bool) Stack {
+	if _, ok := s.Item().(Durable); !ok {
+		return s
+	}
+	s.unbreakable = u
+	return s
+}
+
 // Empty checks if the stack is empty (has a count of 0).
 func (s Stack) Empty() bool {
 	return s.Count() == 0 || s.item == nil