class_name GameMode
extends Node3D

# Base for game modes (Free Play, Match; later Vs-AI and multiplayer).
# A mode's scene contains an Arena (the stadium) and a HUD; the mode itself
# spawns the ball, ships, controllers, and camera in code — variable ship
# counts with mixed controller types (player/AI/network) is exactly what
# future modes need. Subclasses override _start() and _on_goal_scored().

@export var ship_scene: PackedScene = preload("res://objects/ship.tscn")
@export var ball_scene: PackedScene = preload("res://objects/ball.tscn")

const CAMERA_RIG_SCENE = preload("res://scenes/ship_camera_rig.tscn")
const MAIN_MENU_SCENE_PATH = "res://scenes/main_menu.tscn"

var arena: Arena
var ball: RigidBody3D
var ships: Array[Ship] = []
var _ship_spawn_transforms := {}


func _ready():
	# Group lets the HUD discover the game mode for timer/score signals
	add_to_group("game")
	for child in get_children():
		if child is Arena:
			arena = child
			break
	if not arena:
		push_error("GameMode: scene has no Arena child")
		return
	for goal in arena.get_goals():
		goal.goal_scored.connect(_handle_goal_scored)
	_start()


# Virtual: subclasses spawn their ball/ships/camera here.
func _start() -> void:
	pass


# Virtual: the ball entered the goal owned (conceded) by `_conceding_team`.
func _on_goal_scored(_conceding_team: int) -> void:
	pass


# Debounce: a fast ball can re-trigger the goal area before the deferred
# reset teleports it away, which would double-count the goal.
var _goal_cooldown := false

func _handle_goal_scored(conceding_team: int) -> void:
	if _goal_cooldown:
		return
	_goal_cooldown = true
	get_tree().create_timer(0.5).timeout.connect(func(): _goal_cooldown = false)
	_on_goal_scored(conceding_team)


func spawn_ball() -> RigidBody3D:
	ball = ball_scene.instantiate()
	add_child(ball)
	ball.global_transform = arena.get_ball_spawn()
	return ball


func spawn_ship(team: int, spawn_index: int = 0, controller: ShipController = null) -> Ship:
	var ship: Ship = ship_scene.instantiate()
	ship.name = "ShipTeam%d_%d" % [team, ships.size()]
	add_child(ship)
	var spawns := arena.get_ship_spawns(team)
	var spawn_transform := spawns[spawn_index] if spawn_index < spawns.size() else Transform3D.IDENTITY
	ship.global_transform = spawn_transform
	ship.team = team
	if controller:
		ship.set_controller(controller)
	ships.append(ship)
	_ship_spawn_transforms[ship] = spawn_transform
	return ship


func spawn_camera_rig(target: Ship) -> ShipCameraRig:
	var rig: ShipCameraRig = CAMERA_RIG_SCENE.instantiate()
	add_child(rig)
	rig.target = target
	return rig


func reset_ball() -> void:
	if is_instance_valid(ball):
		_reset_body(ball, arena.get_ball_spawn())


func reset_ships() -> void:
	for ship in ships:
		if is_instance_valid(ship):
			_reset_body(ship, _ship_spawn_transforms[ship])


func _reset_body(body: RigidBody3D, to: Transform3D) -> void:
	# Deferred: a RigidBody3D transform can't be set mid-physics-step
	body.set_deferred("global_transform", to)
	body.set_deferred("linear_velocity", Vector3.ZERO)
	body.set_deferred("angular_velocity", Vector3.ZERO)


func _unhandled_input(event):
	if event.is_action_pressed("ui_cancel"):
		get_tree().change_scene_to_file(MAIN_MENU_SCENE_PATH)