extends Node

const TERRAIN_LAYER_ID: int = 0
const OBSTACLE_LAYER_ID: int = 1
const TERRAIN_SOURCE_ID: int = 1
const OBSTACLE_SOURCE_ID: int = 2
const CHUNK_SIZE: int = 15
const CLEAN_UP_EVERY: int = 3
const OBSTACLE_PROBABILITY: float = 0.01

var _source: TileSetAtlasSource
var _obstacle_source: TileSetAtlasSource
var _tile_probabilities: Dictionary
var _obstacle_probabilities: Dictionary
var _clean_up_counter: int

const CHUNK_DOUBLE: int = CHUNK_SIZE*2;

const GREEN_TILE: Vector2i  = Vector2i(1, 1)

var tilemap: TileMap;

@onready var Player = $Player/AnimatedSprite2D
@onready var GroundLayer: TileMapLayer = $Ground

func _get_player_position() -> Vector2i:
	var playerPosition: Vector2i = GroundLayer.local_to_map(Player.global_position)
	print("Playerposition is " + str(playerPosition))
	return playerPosition

# Called when the node enters the scene tree for the first time.
func _ready() -> void:
	_source = $Ground.tile_set.get_source(TERRAIN_SOURCE_ID) as TileSetAtlasSource
	var grid_size: Vector2i = _source.get_atlas_grid_size()
	for i in range(grid_size.x):
		for j in range(grid_size.y):
			var atlas_coords: Vector2i = Vector2i(i, j)
			var has_tile: bool = _source.has_tile(atlas_coords)
			_tile_probabilities[atlas_coords] = (_source.get_tile_data(atlas_coords, 0).probability if has_tile else 0.0)


# Called every frame. 'delta' is the elapsed time since the previous frame.
func _process(delta: float) -> void:
	pass

func _on_exited_chunk():
	print("Chunk exited...")
	$VisibleOnScreenNotifier2D.global_position = Player.global_position
	
	var thread: Thread = Thread.new()
	thread.start(func(): _populate_terrain())
	thread.wait_to_finish()

func populate_terrain(startPos: Vector2i):
	for i in range(-CHUNK_DOUBLE, CHUNK_DOUBLE):
		for j in range(-CHUNK_DOUBLE, CHUNK_DOUBLE):
			var pos: Vector2i = startPos + Vector2i(i, j)
			if _is_empty(pos):
				_populate_cell(pos, 1, _pick_random_tile())
	
func _populate_terrain():
	var player_position: Vector2i = _get_player_position()
	
	for i in range(-CHUNK_DOUBLE, CHUNK_DOUBLE):
		for j in range(-CHUNK_DOUBLE, CHUNK_DOUBLE):
			var pos: Vector2i = player_position + Vector2i(i, j)
			if _is_empty(pos):
				_populate_cell(pos, 1, _pick_random_tile())
				

func _populate_cell(coords: Vector2i, source_id: int, atlas_coords: Vector2i) -> void:
	var alternativeTilesCount: int = GroundLayer.tile_set.get_source(source_id).get_alternative_tiles_count(atlas_coords)
	var alternativeTileId: int = 0
	
	if alternativeTilesCount > 0:
		alternativeTileId = randi_range(0, alternativeTilesCount-1)
	
	# set_cell(coords: Vector2i, source_id: int = -1, atlas_coords: Vector2i = Vector2i(-1, -1), alternative_tile: int = 0)
	GroundLayer.set_cell.call_deferred(coords, source_id, atlas_coords, alternativeTileId)
	
	
func _pick_random_tile() -> Vector2i:
	# Make all Tiles green
	return Vector2i(1, 1)
	
func _is_empty(pos: Vector2i) -> bool:
	# Check if the cell is empty (source_id is -1)
	return true if GroundLayer.get_cell_source_id(pos) == -1 else false;