class_name World extends Node3D

@export var players: Array

@onready var score_update_timer: Timer = $ScoreUpdateTimer
@onready var pixel_count_compute_shader: PixelCountComputeShader = $PixelCountComputeShader

@onready var camera: Camera3D = $Camera3D
@onready var level: Node3D = $Level
@onready var world_coloring_viewport: SubViewport = $WorldColoringViewport

var camera_position: Vector3;
var world_coloring_material: ShaderMaterial
var world_plane: Plane = Plane(Vector3.UP, Vector3.ZERO)
var spawn_points: Array = Array()

# Called when the node enters the scene tree for the first time.
func _ready():
	var player1: CharacterBody3D = $Player1
	var player2: CharacterBody3D = $Player2

	players.append(player1)
	players.append(player2)

	if players.size() == 1:
		world_coloring_material = load("res://materials/WorldColoringMaterialPass.tres")
		world_coloring_material.set_shader_parameter("world_color_texture", world_coloring_viewport.get_texture())
	else:
		world_coloring_material = load("res://materials/WorldColoringMaterialPassVersus.tres")
		world_coloring_material.set_shader_parameter("world_color_texture", world_coloring_viewport.get_texture())

	camera_position = camera.global_position

	score_update_timer.connect("timeout", update_score)

	find_spawn_points(level)
	
	for player: Player in players:
		player.state = player.PlayerState.Dead
	
	apply_world_coloring_recursive(level)

# Called every frame. 'delta' is the elapsed time since the previous frame.
func _process(_delta):
	var player1 : Player = players[0]
	var player_center = Vector3.ZERO
	var player_coords_rect : Rect2 = Rect2(
		player1.global_position.x,
		player1.global_position.z,
		0,
		0,
		)
	
	for player: CharacterBody3D in players:
		player_center += player.global_position
		player_coords_rect = player_coords_rect.expand(Vector2(player.global_position.x, player.global_position.z))

	player_center = player_center / players.size()
	player_center.y = 0
	
	var view_width = player_coords_rect.size.x + 10
	var view_height = player_coords_rect.size.y + 15
	var camera_dist = max (view_width, view_height) * 0.5 / sin(deg_to_rad(camera.fov) * 0.5)

	var camera_direction : Vector3 = -camera.basis.z
	camera_position = player_center - camera_direction * camera_dist
	
	camera.global_position = camera_position
	pass

func _physics_process(_delta):
	world_coloring_material.set_shader_parameter("world_color_texture", world_coloring_viewport.get_texture())
	
	for player: Player in players:
		if player.state == Player.PlayerState.Dead:
			var occupied = true
			var spawn_point
			
			while occupied:
				spawn_point = spawn_points.pick_random() as SpawnPoint
				if not spawn_point.is_occupied():
					occupied = false
			
			player.global_position = spawn_point.global_position
			player.state = Player.PlayerState.Alive
			spawn_point.near_players.append(player)

func find_spawn_points (node):
	for child in node.get_children():
		var spawn_point = child as SpawnPoint
		if spawn_point:
			spawn_points.append(spawn_point)

func apply_world_coloring_recursive (node):
	for child in node.get_children():
		var mesh_instance := child as MeshInstance3D
		if mesh_instance:
			assign_world_coloring_pass(mesh_instance)

		apply_world_coloring_recursive(child)

func assign_world_coloring_pass(mesh_instance: MeshInstance3D) -> void:
	var material = mesh_instance.get_active_material(0)
	if not material:
		return

	material.next_pass = world_coloring_material

func update_score():
	pixel_count_compute_shader.recalculate_score()
	
	players[0].score = pixel_count_compute_shader.red_score
	
	if players.size() > 1:
		players[1].score = pixel_count_compute_shader.blue_score