class_name Building extends Node2D

@export var location : Vector2i # x is the angle, y is the height in the grid
@export var dimension : Vector2i = Vector2(2, 1) # same as above
@export var blocks_area = true

var objects = []
var destroyed = false

# make sure location is set before adding a building to the scene tree
# also make sure that the buildings are instantiated as children of the grid
func _ready() -> void:
	global_position = Grid.get_world_position(location)
	
	if blocks_area:
		Grid.buildings.append(self)
	
	#await get_tree().create_timer(0.2).timeout
	if get_node_or_null("ObjectList") != null:
		var obj_list = $ObjectList
		obj_list.call_deferred("reparent", get_tree().get_root().get_node("main"), false)
		await get_tree().create_timer(0.2).timeout
		var objects_to_be_placed = obj_list.get_children()
		for object in objects_to_be_placed:
			var offset = object.global_position;
			object.global_position = Grid.get_world_position(location, offset)
			
			# The building remembers these objects: If it is destroyed, so are they.
			if object is Platform or object is Trap or object is Item:
				objects.append(object)
				if "building" in object: object.building = self
			# This scales platforms hoizontally to make sure they still form a floor without gaps.
			if(object.has_method("init_at_horizontal_distortion")):
				object.init_at_horizontal_distortion(object.position.length() / Grid.ground_radius)
			grid_entrance_callback(object)

func grid_entrance_callback(object : Node):
	# Objects receive a callback when placed, starting from the deepest children
	for child in object.get_children():
		grid_entrance_callback(child)
	if object.has_method("_enter_grid"):
		object.call_deferred("_enter_grid")

func overlaps(other : Building):
	# heights don't overlap
	if location.y >= other.location.y + other.dimension.y: return false # other is below
	if location.y + dimension.y <= other.location.y: return false # other is above
	
	# angles overlap. We can now assume heights overlap
	var relative_other_loc = (other.location.x - location.x + Grid.num_collumns) % Grid.num_collumns
	if dimension.x > relative_other_loc: return true
	if relative_other_loc + other.dimension.x > Grid.num_collumns: return true
	
	# If we get here, angles do not overlap
	return false

func destroy():
	if not destroyed:
		# On destruction, the building is removed from the list and destroyed together with all its objects.
		Grid.buildings.remove_at(Grid.buildings.find(self))
		for object in objects:
			if object != null and not ("collected" in object and object.collected):
				object.queue_free()
		destroyed = true
		queue_free()