extends Node2D

const BUILDING_DEFINITIONS = preload("res://buildings/BuildingDefinitions.gd")

@export var definition_id: String = "mothership"
@export var building_id: int = 0
@export var interact_radius: float = 150.0

var definition: Resource
var visual: Node2D

var building_type: String:
	get: return definition_id
	set(value): definition_id = value


# #99: drawn only once the structure has actually been hit. A full bar over
# every building would be permanent clutter saying nothing, and the fleet
# would be flying over a field of meters in peacetime.
const HEALTH_BAR_WIDTH: float = 74.0
const HEALTH_BAR_HEIGHT: float = 7.0
const HEALTH_BAR_OFFSET: float = -78.0
const HEALTH_FULL_COLOR: Color = Color(0.45, 0.9, 0.55)
const HEALTH_HURT_COLOR: Color = Color(1.0, 0.35, 0.25)

var _drawn_health: float = 1.0


func _ready() -> void:
	add_to_group("buildings")
	z_index = -1
	definition = BUILDING_DEFINITIONS.get_definition(definition_id)
	if definition == null or definition.visual_scene == null:
		return
	visual = definition.visual_scene.instantiate()
	get_node("VisualHost").add_child(visual)


func health_fraction() -> float:
	return GameState.building_health_fraction(building_id) if building_id != 0 else 1.0


func is_damaged() -> bool:
	return health_fraction() < 0.999


func _process(_delta: float) -> void:
	# Redraw only when the number moves. A building that is not being shot at
	# costs nothing, which is the same bargain Ship.gd's constant glow makes.
	var health: float = health_fraction()
	if is_equal_approx(health, _drawn_health):
		return
	_drawn_health = health
	queue_redraw()


func _draw() -> void:
	if not is_damaged():
		return
	# Above the structure rather than across it: the visual scenes all draw
	# around their own origin, and a bar laid over one would be read as part
	# of the building.
	var health: float = health_fraction()
	var left: float = -HEALTH_BAR_WIDTH * 0.5
	var top: float = HEALTH_BAR_OFFSET
	draw_rect(Rect2(left, top, HEALTH_BAR_WIDTH, HEALTH_BAR_HEIGHT),
		Color(0.02, 0.02, 0.06, 0.85))
	draw_rect(Rect2(left, top, HEALTH_BAR_WIDTH * health, HEALTH_BAR_HEIGHT),
		HEALTH_HURT_COLOR.lerp(HEALTH_FULL_COLOR, health))
	draw_rect(Rect2(left, top, HEALTH_BAR_WIDTH, HEALTH_BAR_HEIGHT),
		Color(0.55, 0.78, 0.86, 0.55), false, 1.0)


func available_actions() -> PackedStringArray:
	if visual == null:
		return PackedStringArray()
	var provider: Node = visual.get_node_or_null("ActionProvider")
	return provider.actions if provider != null else PackedStringArray()


func primary_action() -> String:
	for action in available_actions():
		if action != "transfer" and action != "hangar":
			return action
	return ""


func get_display_name() -> String:
	return String(definition.display_name) if definition != null else definition_id.capitalize()