extends SceneTree

# Headless gameplay test: run with
#   godot --headless -s res://tests/test_fleet_cargo_limit.gd
# Forgejo #56: the fleet hold has a finite, composition-driven capacity
# instead of being unbounded.
#
# Covers:
#   A. capacity is data-driven: only vessels with the "cargo" capability
#      contribute their cargo_capacity stat - combat specialists (shield,
#      gas bomber) contribute zero
#   B. a lone interceptor cannot carry more than its capacity - a further
#      Rock pickup is refused and the rock is not consumed
#   C. losing a cargo-capable ship lowers the ceiling immediately without
#      deleting cargo already held (clamps on the next deposit instead)
#   D. a transfer into a full hold clamps to the remaining space and
#      reports the amount actually moved
#   E. capacity survives the space -> surface scene swap

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


func _initialize() -> void:
	game_state = root.get_node("GameState")
	game_state.buildings.clear()
	game_state.extractors.clear()
	game_state.rocks = 500
	game_state.fleet_cargo = 0
	mothership_id = game_state.add_building(GameState.BUILDING_MOTHERSHIP, Vector2.ZERO)
	scene = load("res://world/Main.tscn").instantiate()
	root.add_child(scene)
	current_scene = scene


func _process(delta: float) -> bool:
	elapsed += delta
	match stage:
		0:
			if elapsed < 0.3:
				return false
			scene.get_node("AsteroidField").set_process(false)
			scene.get_node("EnemySpawner").set_process(false)
			fleet = scene.get_node("Fleet")

			# --- A. capacity is data-driven ---------------------------------
			fleet.spawn_ships(1, Vector2.ZERO, PackedStringArray(["interceptor"]))
			if game_state.fleet_cargo_total_capacity() != 20:
				return _fail("one interceptor: capacity %d, expected 20" % game_state.fleet_cargo_total_capacity())

			fleet.spawn_ships(2, Vector2.ZERO, PackedStringArray(["shield", "gas_bomber"]))
			if game_state.fleet_cargo_total_capacity() != 0:
				return _fail("shield+gas_bomber: capacity %d, expected 0" % game_state.fleet_cargo_total_capacity())
			print("capacity is data-driven: interceptor=20, shield+gas_bomber=0")

			# --- B. a full hold refuses a pickup, the rock stays ------------
			fleet.spawn_ships(1, Vector2.ZERO, PackedStringArray(["interceptor"]))
			game_state.fleet_cargo = 20
			rock = 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 = 1
			return false
		1:
			if elapsed < 0.3:
				return false
			if game_state.fleet_cargo != 20:
				return _fail("a full hold still absorbed a pickup: hold=%d" % game_state.fleet_cargo)
			if not is_instance_valid(rock):
				return _fail("the rock was consumed even though the hold was full")
			print("full hold (20/20) refused a pickup, the rock remains")

			# --- C. losing a cargo ship drops the ceiling, keeps the cargo --
			# Mirrors Ship.gd's own death sequence (destroyed.emit() then
			# queue_free()) rather than just calling the handler, so no
			# untracked ghost ship is left sitting in the scene.
			var dying_ship: Node = fleet.ships[0]
			fleet._on_ship_destroyed(dying_ship)
			dying_ship.queue_free()
			if game_state.fleet_cargo_total_capacity() != 0:
				return _fail("empty fleet: capacity %d, expected 0" % game_state.fleet_cargo_total_capacity())
			if game_state.fleet_cargo != 20:
				return _fail("existing cargo was deleted when capacity dropped below it: %d" % game_state.fleet_cargo)
			print("losing the ship: capacity=0, existing cargo untouched at %d" % game_state.fleet_cargo)

			if game_state.collect_cargo(5) != 0:
				return _fail("an over-capacity hold accepted a further deposit")
			print("over-capacity hold clamps further deposits to zero, as documented")

			# --- D. a transfer into a hold with partial room clamps ---------
			fleet.spawn_ships(2, Vector2.ZERO, PackedStringArray(["interceptor", "interceptor"]))
			if game_state.fleet_cargo_total_capacity() != 40:
				return _fail("two interceptors: capacity %d, expected 40" % game_state.fleet_cargo_total_capacity())
			var bank_before: int = game_state.rocks
			var moved: int = game_state.transfer_resource_to_fleet(mothership_id, GameState.RESOURCE_ORE, 100)
			if moved != 20:
				return _fail("transfer into 20/40 room reported moved=%d, expected 20" % moved)
			if game_state.fleet_cargo != 40:
				return _fail("hold after the clamped transfer is %d, expected 40 (full)" % game_state.fleet_cargo)
			if game_state.rocks != bank_before - 20:
				return _fail("bank dropped by %d, expected exactly the 20 that moved" % (bank_before - game_state.rocks))
			print("transfer into 20/40 room clamped to 20, hold now full, bank debited exactly 20")

			# --- E. capacity survives the space -> surface scene swap -------
			game_state.surviving_ship_count = 2
			game_state.surviving_vessel_types = PackedStringArray(["interceptor", "interceptor"])
			game_state.planet_id = "test_fleet_cargo_limit"
			game_state.planet_name = "Cargo Limit Test"
			scene.queue_free()
			elapsed = 0.0
			stage = 2
			return false
		2:
			# A tick for queue_free() to actually leave the tree before adding
			# the surface scene, matching the shape of every other scene-swap
			# test in this suite.
			if elapsed < 0.3:
				return false
			scene = load("res://surface/PlanetSurface.tscn").instantiate()
			root.add_child(scene)
			current_scene = scene
			elapsed = 0.0
			stage = 3
			return false
		3:
			if elapsed < 0.3:
				return false
			if game_state.fleet_cargo_total_capacity() != 40:
				return _fail("capacity after the surface restore is %d, expected 40" % game_state.fleet_cargo_total_capacity())
			if game_state.fleet_cargo != 40:
				return _fail("cargo did not survive the scene swap: %d, expected 40" % game_state.fleet_cargo)
			print("capacity (40) and cargo (40) both survived the space -> surface swap")
			print("TEST_FLEET_CARGO_LIMIT: PASS")
			quit(0)
			return true
	return false


func _fail(message: String) -> bool:
	print("TEST_FLEET_CARGO_LIMIT: FAIL (%s)" % message)
	quit(1)
	return true