extends Node

const TILE_SIZE := 8.0
const GRID_SIZE := 3
const ENEMY_COUNT := 3
const WIN_MESSAGE_SECONDS := 1.5
const WALL_HEIGHT := 6.0
const WALL_THICKNESS := 1.0

const PLAIN_TILES := [
	preload("res://world/arena/tiles/arena_tile_plain_a.tscn"),
	preload("res://world/arena/tiles/arena_tile_plain_b.tscn"),
	preload("res://world/arena/tiles/arena_tile_plain_c.tscn"),
	preload("res://world/arena/tiles/arena_tile_plain_d.tscn"),
]
const OBSTACLE_TILES := [
	preload("res://world/arena/tiles/arena_tile_obstacle_a.tscn"),
	preload("res://world/arena/tiles/arena_tile_obstacle_b.tscn"),
]
const ENEMY_SCENE := preload("res://world/enemy/enemy.tscn")

var _current_poi: Node = null
var _live_enemies: int = 0

# Baut die Arena bei jedem Aufruf komplett neu (nur eine gleichzeitig aktiv) und
# teleportiert den Spieler hinein. 3x3-Raster aus den Kacheln, Mittelfeld immer
# ein Boden-Stück (damit niemand auf einem Hindernis landet).
func start_arena(poi: Node) -> void:
	_current_poi = poi
	var arena_root := get_tree().get_first_node_in_group("arena_root")
	if arena_root == null:
		push_error("ArenaRoot nicht gefunden! Gruppe 'arena_root' gesetzt?")
		return

	for child in arena_root.get_children():
		child.queue_free()

	_build_walls(arena_root)

	var half := float(GRID_SIZE) * TILE_SIZE * 0.5
	var center_index := GRID_SIZE / 2
	var spawn_cells: Array[Vector3] = []

	for gx in range(GRID_SIZE):
		for gz in range(GRID_SIZE):
			var is_center := gx == center_index and gz == center_index
			var palette := PLAIN_TILES if is_center else (PLAIN_TILES + OBSTACLE_TILES)
			var tile_scene: PackedScene = palette[randi() % palette.size()]
			var tile := tile_scene.instantiate()
			var local_pos := Vector3(
				gx * TILE_SIZE - half + TILE_SIZE * 0.5,
				0.0,
				gz * TILE_SIZE - half + TILE_SIZE * 0.5
			)
			tile.position = local_pos
			arena_root.add_child(tile)
			if not is_center:
				spawn_cells.append(local_pos)

	spawn_cells.shuffle()
	_live_enemies = 0
	for i in range(min(ENEMY_COUNT, spawn_cells.size())):
		var enemy := ENEMY_SCENE.instantiate()
		arena_root.add_child(enemy)
		enemy.global_position = arena_root.global_position + spawn_cells[i] + Vector3(0, 1.0, 0)
		_live_enemies += 1

	var player := get_tree().get_first_node_in_group("player")
	if player:
		player.global_position = arena_root.global_position + Vector3(0, 1.0, 0)

func on_enemy_died(enemy: Node) -> void:
	enemy.queue_free()
	_live_enemies -= 1
	if _live_enemies <= 0:
		_on_win()

func _on_win() -> void:
	var poi := _current_poi
	if poi and poi.has_method("mark_visited"):
		poi.mark_visited()
	InteractionManager.open_message(poi, "Sieg!", "Die Gegner wurden besiegt.")
	var timer := get_tree().create_timer(WIN_MESSAGE_SECONDS)
	timer.timeout.connect(_on_win_message_done)

func _on_win_message_done() -> void:
	InteractionManager.close()
	var player := get_tree().get_first_node_in_group("player")
	if player and _current_poi:
		player.global_position = _current_poi.global_position + Vector3(0, 0.5, 0.6)
	_current_poi = null

func _build_walls(arena_root: Node3D) -> void:
	var half := float(GRID_SIZE) * TILE_SIZE * 0.5
	var barrier := StaticBody3D.new()
	barrier.name = "ArenaWalls"
	arena_root.add_child(barrier)

	var configs := [
		{"size": Vector3(WALL_THICKNESS, WALL_HEIGHT, half * 2.0), "pos": Vector3(half, WALL_HEIGHT * 0.5, 0)},
		{"size": Vector3(WALL_THICKNESS, WALL_HEIGHT, half * 2.0), "pos": Vector3(-half, WALL_HEIGHT * 0.5, 0)},
		{"size": Vector3(half * 2.0, WALL_HEIGHT, WALL_THICKNESS), "pos": Vector3(0, WALL_HEIGHT * 0.5, half)},
		{"size": Vector3(half * 2.0, WALL_HEIGHT, WALL_THICKNESS), "pos": Vector3(0, WALL_HEIGHT * 0.5, -half)},
	]
	for cfg in configs:
		var box := BoxShape3D.new()
		box.size = cfg["size"]
		var cs := CollisionShape3D.new()
		cs.shape = box
		cs.position = cfg["pos"]
		barrier.add_child(cs)