extends Node2D

# Rebuilds every player-placed structure from GameState when the space
# scene loads, and answers "is the fleet standing on one?".
#
# Buildings live in GameState rather than in the scene because Main.tscn is
# torn down and recreated on every trip to a planet's surface - anything
# kept only as a node would be lost on the first landing.

@onready var fleet: Node2D = get_node("../Fleet")

var building_scene: PackedScene = preload("res://buildings/Building.tscn")
var spawned: Array = []

# Nothing happens here per frame any more. Arriving at the mothership used to
# bank the fleet's hold automatically (#14), edge-triggered so that ore
# withdrawn while parked was not instantly taken back. #24 removes it
# entirely: unloading is now an explicit move in the transfer menu, in both
# directions and at every building, so an automatic one-way exception at the
# mothership was the odd case out - and it silently overrode a player who had
# just loaded the hold in order to carry ore somewhere else.


func _ready() -> void:
	# #99: the record is the truth, so the node follows it out. Connected
	# here rather than in Building.gd because the field owns `spawned` and
	# would otherwise be left holding a freed node.
	if not GameState.building_destroyed.is_connected(_on_building_destroyed):
		GameState.building_destroyed.connect(_on_building_destroyed)
	rebuild_all()


func _on_building_destroyed(building_id: int, _type: String) -> void:
	var kept: Array = []
	for b in spawned:
		if not is_instance_valid(b):
			continue
		if int(b.building_id) == building_id:
			BuildingExplosionVFX.spawn(get_tree().root, b.global_position)
			b.queue_free()
			continue
		kept.append(b)
	spawned = kept


func rebuild_all() -> void:
	for b in spawned:
		if is_instance_valid(b):
			b.queue_free()
	spawned.clear()
	for record in GameState.buildings:
		_spawn(record)


func place(type: String, at_position: Vector2) -> void:
	GameState.add_building(type, at_position)
	_spawn(GameState.buildings[-1])


func get_building_fleet_is_on() -> Node2D:
	var centre: Vector2 = fleet.get_centroid()
	for b in spawned:
		if is_instance_valid(b) and b.position.distance_to(centre) <= b.interact_radius:
			return b
	return null


func _spawn(record: Dictionary) -> void:
	var b: Node2D = building_scene.instantiate()
	b.position = record.position
	b.definition_id = record.type
	b.building_id = int(record.get("id", 0))
	# Deferred for the same reason as the other field spawners: this can run
	# from inside a parent's _ready() chain, where a direct add_child() is
	# rejected while the tree is still setting up children.
	get_parent().add_child.call_deferred(b)
	spawned.append(b)