requested changes

server/block/hopper.go

@@ -30,9 +30,9 @@ type Hopper struct {
 
 	// LastTick is the last world tick that the hopper was ticked.
 	LastTick int64
-	// TransferCooldown is the duration until the hopper can transfer items again.
+	// TransferCooldown is the duration in ticks until the hopper can transfer items again.
 	TransferCooldown int64
-	// CollectCooldown is the duration until the hopper can collect items again.
+	// CollectCooldown is the duration in ticks until the hopper can collect items again.
 	CollectCooldown int64
 
 	inventory *inventory.Inventory
@@ -77,7 +77,7 @@ func (h Hopper) BreakInfo() BreakInfo {
 }
 
 // Inventory returns the inventory of the hopper.
-func (h Hopper) Inventory(w *world.World, pos cube.Pos) *inventory.Inventory {
+func (h Hopper) Inventory(*world.World, cube.Pos) *inventory.Inventory {
 	return h.inventory
 }
 
@@ -134,10 +134,17 @@ func (h Hopper) Tick(currentTick int64, pos cube.Pos, w *world.World) {
 	h.CollectCooldown--
 	h.LastTick = currentTick
 
-	if !h.Powered && h.TransferCooldown < 0 {
+	if !h.Powered && h.TransferCooldown <= 0 {
 		inserted := h.insertItem(pos, w)
 		extracted := h.extractItem(pos, w)
 		if inserted || extracted {
+			if h.Facing == cube.FaceDown {
+				if hopper, ok := w.Block(pos.Side(h.Facing)).(Hopper); ok {
+					hopper.TransferCooldown = 8
+					w.SetBlock(pos.Side(h.Facing), hopper, nil)
+				}
+			}
+
 			h.TransferCooldown = 8
 		}
 	}
@@ -157,6 +164,12 @@ func (h Hopper) insertItem(pos cube.Pos, w *world.World) bool {
 		return e.InsertItem(h, pos.Side(h.Facing), w)
 	}
 
+	if hopper, ok := dest.(Hopper); ok {
+		if hopper.TransferCooldown > 0 {
+			return false
+		}
+	}
+
 	if container, ok := dest.(Container); ok {
 		for sourceSlot, sourceStack := range h.inventory.Slots() {
 			if sourceStack.Empty() {
@@ -191,6 +204,12 @@ func (h Hopper) extractItem(pos cube.Pos, w *world.World) bool {
 		return e.ExtractItem(h, pos, w)
 	}
 
+	if hopper, ok := origin.(Hopper); ok {
+		if hopper.TransferCooldown > 0 {
+			return false
+		}
+	}
+
 	if containerOrigin, ok := origin.(Container); ok {
 		for slot, stack := range containerOrigin.Inventory(w, originPos).Slots() {
 			if stack.Empty() {
@@ -201,8 +220,9 @@ func (h Hopper) extractItem(pos cube.Pos, w *world.World) bool {
 			_, err := h.inventory.AddItem(stack.Grow(-stack.Count() + 1))
 			if err != nil {
 				// The hopper is full.
-				return false
+				continue
 			}
+
 			_ = containerOrigin.Inventory(w, originPos).SetItem(slot, stack.Grow(-1))
 			return true
 		}

server/block/smelter.go

@@ -94,7 +94,7 @@ func (s *smelter) ExtractItem(h Hopper, pos cube.Pos, w *world.World) bool {
 
 		if sourceSlot == 1 {
 			fuel, ok := sourceStack.Item().(item.Fuel)
-			if !ok || fuel.FuelInfo().Duration.Seconds() != 0 {
+			if ok && fuel.FuelInfo().Duration.Seconds() != 0 {
 				continue
 			}
 		}
@@ -104,6 +104,7 @@ func (s *smelter) ExtractItem(h Hopper, pos cube.Pos, w *world.World) bool {
 			// The hopper is full.
 			continue
 		}
+
 		_ = s.Inventory(w, pos).SetItem(sourceSlot, sourceStack.Grow(-1))
 		return true
 	}

server/entity/item_behaviour.go

@@ -73,14 +73,14 @@ func (i *ItemBehaviour) Tick(e *Ent) *Movement {
 
 	bl, ok := w.Block(blockPos).(block.Hopper)
 	if ok && !bl.Powered && bl.CollectCooldown <= 0 {
-		addedCount, err := bl.Inventory(w, pos).AddItem(i.i)
+		addedCount, err := bl.Inventory(w, blockPos).AddItem(i.i)
 		if err != nil {
 			if addedCount == 0 {
 				return i.passive.Tick(e)
 			}
 
 			// This is only reached if part of the item stack was collected into the hopper.
-			w.AddEntity(NewItem(i.Item().Grow(addedCount-i.i.Count()), pos.Vec3Centre()))
+			w.AddEntity(NewItem(i.Item().Grow(-addedCount), pos.Vec3Centre()))
 		}
 
 		_ = e.Close()