spaceship/LaserController.gd

class_name LaserController
extends "res://AimedFleetAbilityController.gd"

const BEAM_COLOR := Color(0.3, 0.9, 1.0)
const TARGET_COLOR := Color(0.6, 0.95, 1.0)
const BEAM_HALF_WIDTH := 38.0
# The DRAWN beam is scaled from the hit width rather than tuned separately.
# The two were independent numbers and had drifted apart: the beam struck
# anything within 22 units of the line while its outer glow spanned about 11,
# so it killed things it visibly missed. NeonDraw's widest layer is 18px at
# scale 1, so this makes the glow span exactly what the beam hits.
const BEAM_WIDTH_SCALE := BEAM_HALF_WIDTH * 2.0 / 18.0
const FLASH_DURATION := 0.22
const ENERGY_PER_SHOT: int = 8

var beams: Array = []
var last_hit_count: int = 0


func _button_path() -> NodePath: return "../UI/LaserButton"
func _status_path() -> NodePath: return "../UI/LaserStatus"
func _component_id() -> String: return "laser"
func _ammo_resource() -> String: return GameState.RESOURCE_ENERGY
func _ammo_cost() -> int: return ENERGY_PER_SHOT
func _aim_padding() -> float: return BEAM_HALF_WIDTH
func _has_effect_visuals() -> bool: return not beams.is_empty()


func _aim_max_range() -> float:
	# Falls back to the VESSEL DEFINITION's own beam_range, not to a copy of
	# the number. This used to hardcode 950.0 in both branches, which silently
	# became a lie the moment the definition's range changed - the aim line
	# would have been drawn to a different distance than the beam actually
	# reaches, and only in the cases where the fallback fires.
	var ship: Node2D = _next_ready_ship()
	if ship != null:
		var component: Node = ship.get_component(_component_id())
		if component != null:
			return component.beam_range
	return GameState.vessel_stat(GameState.VESSEL_LASER, "beam_range")


func _calculate_aim_target(drag: Vector2, origin: Vector2) -> Vector2:
	# A beam always reaches full range; dragging chooses its direction only.
	var direction: Vector2 = drag.normalized() if drag.length() > 0.001 else Vector2.UP
	return origin + direction * _aim_max_range()


func _consume_shot(component: Node) -> bool:
	return component.consume_shot()


func _perform_shot(ship: Node2D, component: Node) -> void:
	var direction: Vector2 = aim_target - _aim_origin()
	direction = direction.normalized() if direction.length() > 0.001 else Vector2.UP
	var beam_to: Vector2 = ship.global_position + direction * component.beam_range
	_strike(ship.global_position, beam_to, direction, int(component.damage))


func _next_ready_laser_ship() -> Node2D:
	return _next_ready_ship()


func _advance_effects(delta: float) -> void:
	for i in range(beams.size() - 1, -1, -1):
		var beam: Dictionary = beams[i]
		beam.time = maxf(float(beam.time) - delta, 0.0)
		if float(beam.time) <= 0.0:
			beams.remove_at(i)


func _strike(from: Vector2, to: Vector2, direction: Vector2, damage: int) -> void:
	beams.append({"from": from, "to": to, "time": FLASH_DURATION})
	last_hit_count = 0
	var range_along: float = from.distance_to(to)
	# Asteroids share the enemies' take_damage() contract, so the beam sweeps
	# both groups in one pass. Shooting a path clear through a field is a
	# perfectly good use of a laser, and the ore it leaves behind is the point.
	for enemy in get_tree().get_nodes_in_group("enemies") \
			+ get_tree().get_nodes_in_group("asteroids"):
		if not is_instance_valid(enemy) or not (enemy is Node2D):
			continue
		var to_enemy: Vector2 = enemy.global_position - from
		var along: float = to_enemy.dot(direction)
		if along < 0.0 or along > range_along:
			continue
		var perpendicular: float = (to_enemy - direction * along).length()
		if perpendicular <= BEAM_HALF_WIDTH:
			enemy.take_damage(damage)
			last_hit_count += 1


func _draw() -> void:
	if aiming:
		NeonDraw.draw_glowing_line(self, _aim_origin(), aim_target,
			TARGET_COLOR, 0.7, 0.6)
	for beam in beams:
		var progress: float = 1.0 - float(beam.time) / FLASH_DURATION
		var alpha: float = 1.0 - progress
		NeonDraw.draw_glowing_line(self, beam.from, beam.to,
			BEAM_COLOR, alpha, BEAM_WIDTH_SCALE * (1.0 - progress * 0.45))