## TowerSlot.gd
## A cell on the lane grid where a tower can be placed.
## Uses Area2D input_event for click detection.
class_name TowerSlot
extends Area2D

var player_id: int = 0
var _tower: Node   = null

signal slot_clicked(slot: TowerSlot)

func _ready() -> void:
	input_pickable = true
	input_event.connect(_on_input_event)
	# Tint the visual based on state
	_refresh_visual()

func _on_input_event(_viewport, event: InputEvent, _shape_idx: int) -> void:
	if event is InputEventMouseButton \
	and event.pressed \
	and event.button_index == MOUSE_BUTTON_LEFT:
		slot_clicked.emit(self)

func is_empty() -> bool:
	return _tower == null

func place_tower(tower_data: Dictionary, pid: int) -> bool:
	if not is_empty():
		return false
	var tower_scene := load("res://scenes/gameplay/Tower.tscn") as PackedScene
	if not tower_scene:
		push_error("TowerSlot: Tower.tscn not found")
		return false
	_tower = tower_scene.instantiate()
	_tower.setup(tower_data, pid)
	add_child(_tower)
	_refresh_visual()
	EventBus.tower_placed.emit(pid, tower_data.get("id", ""), self)
	return true

func upgrade_tower(new_tower_data: Dictionary) -> bool:
	if is_empty() or not _tower.can_upgrade():
		return false
	_tower.setup(new_tower_data, _tower.player_id)
	_refresh_visual()
	EventBus.tower_upgraded.emit(_tower.player_id, _tower, new_tower_data.get("id", ""))
	return true

func get_tower() -> Node:
	return _tower

func _refresh_visual() -> void:
	var vis := get_node_or_null("SlotVisual") as ColorRect
	if not vis:
		return
	if is_empty():
		vis.color = Color(0.2, 0.2, 0.2, 0.5)
	else:
		vis.color = Color(0.1, 0.35, 0.15, 0.7)