spaceship/controllers/GasBombController.gd

class_name GasBombController
extends "res://controllers/AimedFleetAbilityController.gd"

const BOMB_COLOR := Color(0.96, 0.22, 0.72)
const TARGET_COLOR := Color(0.78, 0.32, 1.0)
const MAX_RANGE := 950.0
const AOE_RADIUS := 180.0
const DRAG_RADIUS := 260.0
const PROJECTILE_SPEED := 720.0
const DAMAGE := 3
const COOLDOWN := 5.0
const GAS_PER_SHOT: int = 5

var projectiles: Array = []
var explosions: Array = []
var last_hit_count: int = 0

var projectile_active: bool:
	get: return not projectiles.is_empty()

var explosion_time: float:
	get:
		var longest: float = 0.0
		for explosion in explosions:
			longest = maxf(longest, float(explosion.time))
		return longest


func _button_path() -> NodePath: return "../UI/GasBombButton"
func _status_path() -> NodePath: return "../UI/GasBombStatus"
func _component_id() -> String: return "gas_bomber"
func _ammo_resource() -> String: return GameState.RESOURCE_GAS
func _ammo_cost() -> int: return GAS_PER_SHOT
func _aim_padding() -> float: return AOE_RADIUS
func _aim_max_range() -> float: return MAX_RANGE
func _has_effect_visuals() -> bool: return not projectiles.is_empty() or not explosions.is_empty()


func _calculate_aim_target(drag: Vector2, origin: Vector2) -> Vector2:
	if drag.length() < 0.001:
		return origin
	var distance: float = minf(drag.length() / DRAG_RADIUS, 1.0) * MAX_RANGE
	return origin + drag.normalized() * distance


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


func _perform_shot(ship: Node2D, _component: Node) -> void:
	projectiles.append({
		"position": ship.global_position,
		"target": aim_target,
		"trail": PackedVector2Array([ship.global_position]),
	})


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


func _advance_effects(delta: float) -> void:
	for i in range(projectiles.size() - 1, -1, -1):
		var projectile: Dictionary = projectiles[i]
		var distance: float = (projectile.position as Vector2).distance_to(projectile.target)
		if distance <= PROJECTILE_SPEED * delta:
			projectile.position = projectile.target
			_explode(projectile.target)
			projectiles.remove_at(i)
		else:
			projectile.position = (projectile.position as Vector2).move_toward(
				projectile.target, PROJECTILE_SPEED * delta)
			var trail: PackedVector2Array = projectile.trail
			trail.append(projectile.position)
			while trail.size() > 12:
				trail.remove_at(0)
			projectile.trail = trail
	for i in range(explosions.size() - 1, -1, -1):
		var explosion: Dictionary = explosions[i]
		explosion.time = maxf(float(explosion.time) - delta, 0.0)
		if float(explosion.time) <= 0.0:
			explosions.remove_at(i)


func _explode(at: Vector2) -> void:
	explosions.append({"position": at, "time": 0.8})
	last_hit_count = 0
	# Asteroids too - a blast that clears everything around it but leaves the
	# rocks untouched would need explaining, and they take damage the same way.
	for enemy in get_tree().get_nodes_in_group("enemies") \
			+ get_tree().get_nodes_in_group("asteroids"):
		if is_instance_valid(enemy) and enemy is Node2D \
				and enemy.global_position.distance_to(at) <= AOE_RADIUS:
			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, 0.8)
		_draw_ring(aim_target, AOE_RADIUS, TARGET_COLOR, 0.8)
		_draw_ring(aim_target, 18.0, BOMB_COLOR, 1.0)
	for projectile in projectiles:
		var trail: PackedVector2Array = projectile.trail
		if trail.size() >= 2:
			for i in range(1, trail.size()):
				var alpha: float = float(i) / trail.size()
				draw_line(trail[i - 1], trail[i], Color(BOMB_COLOR, alpha * 0.65),
					4.0 + alpha * 4.0, true)
		draw_circle(projectile.position, 12.0, Color(BOMB_COLOR, 0.35))
		NeonDraw.draw_glowing_circle(self, projectile.position, 7.0, BOMB_COLOR, 1.0)
	for explosion in explosions:
		var progress: float = 1.0 - float(explosion.time) / 0.8
		var radius: float = lerpf(24.0, AOE_RADIUS, minf(progress * 1.5, 1.0))
		draw_circle(explosion.position, radius, Color(BOMB_COLOR, (1.0 - progress) * 0.16))
		_draw_ring(explosion.position, radius, BOMB_COLOR, 1.0 - progress)
		for i in range(7):
			var angle: float = TAU * float(i) / 7.0 + progress
			var cloud_at: Vector2 = explosion.position \
				+ Vector2(cos(angle), sin(angle)) * radius * 0.55
			draw_circle(cloud_at, 18.0 + 14.0 * progress,
				Color(BOMB_COLOR, (1.0 - progress) * 0.22))


func _draw_ring(center: Vector2, radius: float, color: Color, alpha: float) -> void:
	draw_arc(center, radius, 0.0, TAU, 64, Color(color, 0.16 * alpha), 16.0, true)
	draw_arc(center, radius, 0.0, TAU, 64, Color(color, 0.5 * alpha), 6.0, true)
	draw_arc(center, radius, 0.0, TAU, 64, Color(1.0, 0.86, 0.96, 0.9 * alpha), 2.0, true)