extends SceneTree

# Headless gameplay test: run with
#   godot --headless -s res://tests/test_fleet_cargo.gd
# Forgejo #14 (part 1 of #12): mined ore is CARGO the fleet is carrying, not
# instant global income. It only becomes spendable once the fleet flies it
# back to the mothership.
#
# Before this, Rock.gd did `GameState.rocks += 1` on pickup, so ore was
# banked instantly from anywhere on the map and a mining run had nothing to
# lose.
#
# Verifies:
#   1. mining fills the hold and leaves the bank alone
#   2. unloading at the mothership banks the lot and empties the hold - but
#      only when the player asks. Arriving used to do it by itself; #24
#      removed that, so this now checks BOTH halves: parking changes
#      nothing, and the explicit transfer moves everything
#   3. with no mothership there is nowhere to deliver, so cargo just
#      accumulates - it is never quietly banked anyway
#   4. sitting on a DIFFERENT building is not a delivery
#   5. ore is conserved: nothing is created or destroyed in the transfer
#   6. cargo survives the trip to a planet's surface and back, which is
#      exactly the trip a mining run is

var game_state: Node
var scene: Node
var fleet: Node
var field: Node
var stage: int = 0
var elapsed: float = 0.0
var banked_before: int = 0
var mothership_id: int = 0

const MOTHERSHIP_AT: Vector2 = Vector2(1200.0, 0.0)
const CRAFTER_AT: Vector2 = Vector2(-4000.0, 0.0)


func _initialize() -> void:
	game_state = root.get_node("GameState")
	game_state.buildings.clear()
	game_state.extractors.clear()
	game_state.rocks = 100
	game_state.fleet_cargo = 0
	scene = load("res://world/Main.tscn").instantiate()
	root.add_child(scene)
	fleet = scene.get_node("Fleet")
	field = scene.get_node("BuildingField")


func _park_fleet_on(at: Vector2) -> void:
	for ship in fleet.ships:
		ship.position = at
	fleet.move_to(at)


func _process(delta: float) -> bool:
	elapsed += delta
	match stage:
		0:
			scene.get_node("AsteroidField").set_process(false)
			scene.get_node("EnemySpawner").set_process(false)

			# --- 1. mining fills the hold, not the bank -----------------
			# Through a REAL Rock, flown over by a real ship, rather than by
			# calling collect_cargo() directly: the whole change is which
			# pool Rock.gd credits on pickup, and a test that calls the new
			# API by hand passes just as happily with Rock.gd left untouched.
			banked_before = game_state.rocks
			var rock: Area2D = load("res://surface/Rock.tscn").instantiate()
			rock.build_shape(1)
			rock.global_position = fleet.ships[0].global_position
			scene.add_child(rock)
			elapsed = 0.0
			stage = 5
			return false
		5:
			# A tick for the Area2D overlap to register.
			if elapsed < 0.25:
				return false
			if game_state.fleet_cargo != 1:
				print("TEST_FLEET_CARGO: FAIL (flying over a rock put %d in the hold)" % game_state.fleet_cargo)
				quit(1)
				return true
			if game_state.rocks != banked_before:
				print("TEST_FLEET_CARGO: FAIL (a mined rock was banked instantly: %d -> %d)" % [
					banked_before, game_state.rocks
				])
				quit(1)
				return true
			print("flew over a real rock -> hold=%d bank=%d (unchanged)" % [
				game_state.fleet_cargo, game_state.rocks
			])

			game_state.collect_cargo(1)
			game_state.collect_cargo(1)
			if game_state.fleet_cargo != 3:
				print("TEST_FLEET_CARGO: FAIL (mining did not fill the hold: %d)" % game_state.fleet_cargo)
				quit(1)
				return true
			if game_state.rocks != banked_before:
				print("TEST_FLEET_CARGO: FAIL (mining banked %d straight away)" % (game_state.rocks - banked_before))
				quit(1)
				return true
			print("mined 3 -> hold=%d bank=%d (unchanged)" % [game_state.fleet_cargo, game_state.rocks])

			# --- 3. no mothership means nowhere to deliver --------------
			_park_fleet_on(Vector2.ZERO)
			elapsed = 0.0
			stage = 1
			return false
		1:
			if elapsed < 0.4:
				return false
			if game_state.fleet_cargo != 3 or game_state.rocks != banked_before:
				print("TEST_FLEET_CARGO: FAIL (delivered with no mothership built)")
				quit(1)
				return true
			print("no mothership -> hold still %d, bank still %d" % [game_state.fleet_cargo, game_state.rocks])

			# --- 4. a different building is not a delivery point --------
			field.place(GameState.BUILDING_SHIP_CRAFTER, CRAFTER_AT)
			field.place(GameState.BUILDING_MOTHERSHIP, MOTHERSHIP_AT)
			mothership_id = int(game_state.buildings[-1].id)
			_park_fleet_on(CRAFTER_AT)
			elapsed = 0.0
			stage = 2
			return false
		2:
			if elapsed < 0.4:
				return false
			if game_state.fleet_cargo != 3:
				print("TEST_FLEET_CARGO: FAIL (the ship crafter accepted a delivery)")
				quit(1)
				return true
			print("parked on the crafter -> hold still %d" % game_state.fleet_cargo)

			# --- 2. the mothership banks it -----------------------------
			_park_fleet_on(MOTHERSHIP_AT)
			elapsed = 0.0
			stage = 3
			return false
		3:
			if elapsed < 0.4:
				return false
			var total_before: int = banked_before + 3
			# Parking alone must do nothing now (#24).
			if game_state.fleet_cargo != 3 or game_state.rocks != banked_before:
				print("TEST_FLEET_CARGO: FAIL (arriving at the mothership banked the hold by itself)")
				quit(1)
				return true
			print("parked on the mothership -> hold still %d (no auto-banking)" % game_state.fleet_cargo)

			game_state.transfer_to_building(mothership_id, 999)
			print("delivered: hold=%d bank=%d (expected hold=0 bank=%d)" % [
				game_state.fleet_cargo, game_state.rocks, total_before
			])
			if game_state.fleet_cargo != 0:
				print("TEST_FLEET_CARGO: FAIL (hold not emptied on delivery)")
				quit(1)
				return true
			# --- 5. conservation ----------------------------------------
			if game_state.rocks != total_before:
				print("TEST_FLEET_CARGO: FAIL (ore was created or destroyed in the transfer)")
				quit(1)
				return true

			# --- 6. cargo survives the scene swap -----------------------
			# Not simulated by loading PlanetSurface.tscn here: the point is
			# that cargo lives in the autoload rather than in Main.tscn, so
			# tearing Main.tscn down must not touch it.
			game_state.collect_cargo(5)
			scene.queue_free()
			elapsed = 0.0
			stage = 4
			return false
		4:
			if elapsed < 0.3:
				return false
			if game_state.fleet_cargo != 5:
				print("TEST_FLEET_CARGO: FAIL (cargo lost when the space scene was torn down: %d)" % game_state.fleet_cargo)
				quit(1)
				return true
			print("cargo survived the scene teardown: hold=%d" % game_state.fleet_cargo)
			print("TEST_FLEET_CARGO: PASS")
			quit(0)
			return true
	return false