class_name Arena
extends Node3D

# A reusable stadium: terrain, lighting, environment, two team goals, and
# spawn markers. An arena holds no rules and no state — game modes query it
# for spawn transforms and goals, then spawn ships/ball themselves.

# Per-arena Environment tuning. These live as exports (rather than baked
# into each arena's Environment sub-resource) because Godot's scene
# inheritance can only override whole top-level node properties, not
# properties nested inside a sub-resource — so each arena_0N.tscn overrides
# these on the Arena root instead, and _ready() applies them here.
@export var sky_material: Material
@export var ambient_light_color := Color(0.55, 0.6, 0.75, 1)
@export var ambient_light_energy := 0.4
@export var glow_intensity := 0.9
@export var glow_strength := 1.2
@export var glow_bloom := 0.05
@export var glow_hdr_threshold := 1.0


var _env: Environment
# Lights authored with shadow_enabled = true (the DirectionalLight3D + 4
# PitchLights omnis) — captured once, before gating ever touches them. Every
# call after the first re-applies VideoSettings.shadows_enabled to exactly
# these lights, so the set can't self-poison (if it were re-derived from
# current state, a light this same code just turned off would look
# indistinguishable from FillLight, which is authored off on purpose and must
# never be turned on by the preset ladder).
var _shadow_capable_lights: Array[Light3D] = []


func _ready():
	add_to_group("arena")
	# A headless server never renders, so duplicating and configuring a full
	# Environment (glow/SSAO/SSIL/SDFGI) for it is pure waste — mirrors the
	# same guard at ship.gd and arena_boundary.gd.
	if DisplayServer.get_name() == "headless":
		return
	var world_env := get_node_or_null("WorldEnvironment") as WorldEnvironment
	if world_env and world_env.environment:
		_env = world_env.environment.duplicate(true) as Environment
		world_env.environment = _env
		if sky_material:
			if not _env.sky:
				_env.sky = Sky.new()
			_env.sky.sky_material = sky_material
		_env.ambient_light_color = ambient_light_color
		_env.ambient_light_energy = ambient_light_energy
		_env.glow_intensity = glow_intensity
		_env.glow_strength = glow_strength
		_env.glow_bloom = glow_bloom
		_env.glow_hdr_threshold = glow_hdr_threshold
		for light in find_children("*", "Light3D", true, false):
			if (light as Light3D).shadow_enabled:
				_shadow_capable_lights.append(light)
		_apply_video_settings()
		# Task 0.17: a preset change from the settings menu must take effect
		# on the arena that's already loaded, not just the next one — this is
		# the "settings persist and apply without a restart" acceptance bar.
		VideoSettings.settings_changed.connect(_apply_video_settings)


# Re-run on every VideoSettings.settings_changed (preset or individual
# toggle) as well as once at load. Shadow gating lives here rather than in
# VideoSettings.apply_to_environment() because it targets Light3D nodes in
# this arena's own tree, not the Environment resource.
func _apply_video_settings() -> void:
	if not is_instance_valid(_env):
		return
	VideoSettings.apply_to_environment(_env)
	for light in _shadow_capable_lights:
		if is_instance_valid(light):
			light.shadow_enabled = VideoSettings.shadows_enabled


func get_ball_spawn() -> Transform3D:
	return $BallSpawn.global_transform


func get_ship_spawns(team: int) -> Array[Transform3D]:
	var spawns: Array[Transform3D] = []
	var container := get_node_or_null("SpawnsTeam%d" % team)
	if container:
		for child in container.get_children():
			if child is Marker3D:
				spawns.append(child.global_transform)
	return spawns


func get_goals() -> Array[Goal]:
	var goals: Array[Goal] = []
	for child in get_children():
		if child is Goal:
			goals.append(child)
	return goals