extends StructureBehaviour

@onready var inventory: SplitterInventory = structure_parent.inventory
var split: bool = true

func get_upper_next() -> Vector2:
	return Vector2.RIGHT.rotated(structure_parent.direction)

func get_down_next() -> Vector2:
	var base = get_upper_next()
	return base + base.rotated(PI/2).abs()

func _process(_delta: float) -> void:
	if has_non_empty(inventory.upper_array) == false and has_non_empty(inventory.down_array) == false:
		return
	var transfer_upper = try_transfer(get_upper_next(),false)
	var transfer_down = try_transfer(get_down_next(),true)
	if transfer_upper or transfer_down or (not transfer_down and not transfer_upper):
		split = not split

func try_transfer(point:Vector2,down:bool) -> bool:
	var next :Structure = structure_parent.get_relative(point)
	var array : Array[InventorySlot] = inventory.down_array if split != down else inventory.upper_array
	if next == null:
		return false
	var context : InventoryContext = InventoryContext.new(structure_parent,next,to_global(point))
	for i in range(inventory.capacity):
		if array[i].amount > 0 and next.inventory.can_add(array[i].held_item,context):
			var stack = array[i].extract()
			stack = next.inventory.add(stack,context)
			array[i].merge_stack(stack)
			
			return true
	return false

func has_non_empty(array:Array[InventorySlot]) -> bool:
	for i in range(inventory.capacity):
		if array[i].amount > 0:
			return true
	return false