extends Node3D

var thread
var displayed_chunks = {}
var unready_chunks = {}

@export var camera: Camera3D
@export var OceanTiles: MultiMeshInstance3D

var chunks: Array

func _ready():
	thread = Thread.new()
	init_chunks()

func init_chunks():
	for x in Global.world.width / Global.world.chunk_size:
		chunks.append([])
		for y in Global.world.height / Global.world.chunk_size:
			chunks[x].append([])
			chunks[x][y] = Chunk.new(x, y, Global.world.chunk_size, chunks)
			chunks[x][y].set_name("Chunk")
			chunks[x][y]

func add_chunk(x, z):
	var key = str(x) + "," + str(z)
	if displayed_chunks.has(key) or unready_chunks.has(key):
		return
	if not thread.is_started():

		thread.start(Callable(self, "load_chunk").bind([thread, x, z]))
		unready_chunks[key] = 1

func load_chunk(array):
	var thread = array[0]
	var posX = array[1]
	var posZ = array[2]

	var x = fmod(posX, Global.world.width / Global.world.chunk_size)
	var z = fmod(posZ, Global.world.height / Global.world.chunk_size)
#
#	# Chargement du chunk
	var chunk = chunks[x][z]
	var chunk_position = Vector2(posX, posZ)
	chunk.position = Vector3(posX * Global.world.chunk_size, 0, posZ * Global.world.chunk_size)
	
#	OceanTiles.multimesh.set_instance_transform()
	call_deferred("load_done", chunk, thread, chunk_position)

func load_done(chunk, thread, position):
	add_child(chunk)
	var key = str(position.x) + "," + str(position.y)
	displayed_chunks[key] = chunk
	unready_chunks.erase(key)
	thread.wait_to_finish()

func get_chunk(x, z):
	var key = str(x) + "," + str(z)
	if displayed_chunks.has(key):
		return displayed_chunks.get(key)

	return null

func _process(delta):
	update_chunks()
	clean_up_chunks()
	reset_chunks()

func update_chunks():
	var camera_translation = camera.position
	var c_x = int(camera_translation.x) / Global.world.chunk_size
	var c_z = int(camera_translation.z) / Global.world.chunk_size

	for x in range(c_x - Global.world.chunk_number * 0.5, c_x + Global.world.chunk_number * 0.53):
		for z in range(c_z - Global.world.chunk_number * 0.6, c_z + Global.world.chunk_number * 0.33):
			add_chunk(x, z)
			var chunk = get_chunk(x, z)
			if chunk != null:
				chunk.should_remove = false

func clean_up_chunks():
	for key in displayed_chunks:
		var chunk = displayed_chunks[key]
		if chunk.should_remove:
			remove_child(chunk)
			displayed_chunks.erase(key)

func reset_chunks():
	for key in displayed_chunks:
		var chunk = displayed_chunks[key]
		chunk.should_remove = true