Add Recipemanager that loads recipes from YAML

Prefabs/combinable_item.gd

@@ -1,24 +1,118 @@
 class_name CombinableItem
 extends Node
 
-## Identity of this item, referenced by other items' recipes.
-@export var id: StringName
+const RECIPE_MANAGER = preload("res://RecipeManager.gd")
 
-## Recipes describing what the item holding this component turns into when
-## another item is combined into it while snapped. Recipes are directional:
-## only the snapped (base) item's recipes are consulted.
-@export var recipes: Array[CombineRecipe] = []
+@onready var combine_area_3d: Area3D = $Area3d
+@onready var _pickable: XRToolsPickable = get_parent() as XRToolsPickable
+
+# Guard so a combine only fires once.
+var _combining: bool = false
+var _food_item: FoodItem
 
 
 func _ready() -> void:
-	if id.is_empty():
-		push_error("CombinableItem on ", get_parent().name, " has no 'id' set.")
+	print("CombinableItem _ready(): ", _pickable.name)
+	_food_item = get_parent().get_node_or_null("FoodItem") as FoodItem
+	if not _food_item:
+		push_error("CombinableItem is missing FoodItem reference. must be a sibling of a FoodItem on ", get_parent().name, ".")
+
+	# Detect items whether held (layer 17 "Held Objects") or loose
+	# (layer 3 "Pickable Objects"). Don't advertise a layer of our own.
+	combine_area_3d.collision_mask = 0b0000_0000_0000_0001_0000_0000_0000_0100
+	combine_area_3d.collision_layer = 0
+	# Deferred: _ready can run during a physics signal flush (when a combine
+	# spawns the result), where toggling monitoring directly is forbidden.
+	set_deferred("monitoring", false)
+	set_deferred("monitorable", false)
+
+	if not _pickable:
+		push_error("CombineZone must be a grand child of an XRToolsPickable.")
+		return
+	if not _food_item:
+		push_error("CombineZone requires a FoodItem sibling on ", _pickable.name, ".")
+		return
+
+	_pickable.picked_up.connect(_on_item_picked_up)
+	_pickable.dropped.connect(_on_item_dropped)
+	combine_area_3d.body_entered.connect(_on_body_entered)
 
 
-## Returns the scene this item becomes when combined with [param other_id],
-## or null if there is no matching recipe.
 func get_result_for(other_id: StringName) -> PackedScene:
-	for recipe in recipes:
-		if recipe and recipe.ingredient_id == other_id:
-			return recipe.result
+	return RECIPE_MANAGER.get_combination(_food_item.id, other_id)
+
+
+## Trigger area that lets a snapped item combine with another item pushed into
+## it. The zone only monitors while its owning item is held by an
+## [XRToolsSnapZone]; when an item carrying a matching [FoodItem.id]
+## enters, the snapped (base) item transforms into the recipe result and the
+## incoming item is consumed.
+
+
+# Enable the trigger only while snapped into a snap zone (not hand-held).
+func _on_item_picked_up(_item: Node3D) -> void:
+	var by := _pickable.get_picked_up_by()
+	var snapped: bool = by != null and by.has_method("is_xr_class") and by.is_xr_class("XRToolsSnapZone")
+	set_deferred("monitoring", snapped)
+
+
+func _on_item_dropped(_item: Node3D) -> void:
+	set_deferred("monitoring", false)
+
+
+func _on_body_entered(body: Node3D) -> void:
+	print("CombinableItem _on_body_entered")
+	if _combining or body == _pickable:
+		print("CombinableItem _on_body_entered: other is our own pickable")
+		return
+
+	var other := _find_food_item(body)
+	if not other:
+		print("CombinableItem _on_body_entered: other is not a foodItem")
+		return
+
+	var result: PackedScene = RecipeManager.get_combination(_food_item.id, other.id)
+	if not result:
+		print("CombinableItem _on_body_entered: There is no recipe for %s + %s" % [_food_item.id, other.id])
+		return
+
+	_combine(body, result)
+
+
+# Transform the base item into [param result], consuming the incoming item.
+func _combine(other_body: Node3D, result: PackedScene) -> void:
+	print("CombinableItem _combine: combining %s + %s into %s" % [_food_item.id, _find_food_item(other_body).id, result.resource_path])
+	_combining = true
+
+	var snap_zone := _pickable.get_picked_up_by()
+	if not snap_zone or not snap_zone.has_method("pick_up_object"):
+		push_warning("CombineZone: base item is not held by a snap zone; cannot combine.")
+		_combining = false
+		return
+
+	# Spawn the result at the base item's location, in world space.
+	var base_transform := _pickable.global_transform
+	var result_instance: Node3D = result.instantiate()
+	_pickable.get_tree().current_scene.add_child(result_instance)
+	result_instance.global_transform = base_transform
+
+	# Free the base item and consume the incoming item.
+	snap_zone.drop_object()
+	_pickable.queue_free()
+	if other_body.has_method("drop_and_free"):
+		other_body.drop_and_free()
+	else:
+		other_body.queue_free()
+
+	# Snap the result into the now-empty zone.
+	snap_zone.pick_up_object(result_instance)
+
+
+# Find a FoodItem among the direct children of [param node].
+func _find_food_item(node: Node) -> FoodItem:
+	if not node:
+		return null
+	for child in node.get_children():
+		if child is FoodItem:
+			return child
 	return null