extends SceneTree

# Headless gameplay test: run with
#   godot --headless -s res://tests/test_gas_burner_pause.gd
# Forgejo #78: a gas burner converts gas the player may want for bombs into
# energy they may not need yet, and until now it did that relentlessly - the
# only way to stop it was to demolish it.
#
# Covers:
#   A. the burner offers a "pause" action, and it is its PRIMARY one, so a
#      single tap on the context button toggles it rather than opening a menu
#   B. a running burner converts gas into energy
#   C. a paused one converts nothing, and keeps its gas
#   D. resuming converts again, and the fraction of a unit already worked
#      through is not thrown away
#   E. the button shows what it will DO - pause bars while running, a play
#      triangle while stopped

var game_state: Node
var main: Node
var controller: Node
var burner_id: int = 0
var stage: int = 0
var elapsed: float = 0.0
var gas_at_pause: int = 0
var energy_at_pause: int = 0


func _initialize() -> void:
	game_state = root.get_node("GameState")
	game_state.buildings.clear()
	game_state.extractors.clear()
	game_state.transporters.clear()
	game_state.reset_progression()
	main = load("res://world/Main.tscn").instantiate()
	root.add_child(main)
	current_scene = main
	controller = main.get_node("BuildController")


func _burner() -> Dictionary:
	return game_state.find_building(burner_id)


func _stock(resource_type: String) -> int:
	return game_state.building_resource(burner_id, resource_type)


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

			# Through the FIELD, not GameState directly: place() both records
			# the building and spawns its node, and part E needs the node.
			main.get_node("BuildingField").place(GameState.BUILDING_GAS_BURNER,
				Vector2(600.0, 0.0))
			burner_id = int(game_state.buildings[0].id)
			game_state.building_inventory(burner_id).deposit(GameState.RESOURCE_GAS, 30)
			if _stock(GameState.RESOURCE_GAS) <= 0:
				return _fail("could not stock the burner with gas")

			# --- A. it offers pause, as its primary action ----------------
			var definition: Resource = load("res://buildings/BuildingDefinitions.gd") \
				.get_definition(GameState.BUILDING_GAS_BURNER)
			var visual: Node = definition.visual_scene.instantiate()
			var provider: Node = visual.get_node_or_null("ActionProvider")
			if provider == null:
				visual.free()
				return _fail("the gas burner visual has no ActionProvider")
			var actions: PackedStringArray = provider.actions
			visual.free()
			if not Array(actions).has("pause"):
				return _fail("the gas burner does not offer a pause action: %s" % str(actions))
			if String(actions[0]) != "pause":
				return _fail("pause is not the burner's primary action (%s comes first), so it would need a menu rather than one tap" % actions[0])
			print("gas burner offers pause as its primary action")
			stage = 1
			elapsed = 0.0
			return false
		1:
			# --- B. running, it converts ----------------------------------
			if elapsed < 1.5:
				return false
			if _stock(GameState.RESOURCE_ENERGY) <= 0:
				return _fail("a running burner made no energy in %.1fs" % elapsed)
			print("running: %d gas left, %d energy made" \
				% [_stock(GameState.RESOURCE_GAS), _stock(GameState.RESOURCE_ENERGY)])

			if game_state.is_building_paused(burner_id):
				return _fail("the burner started out paused")
			if not game_state.toggle_building_paused(burner_id):
				return _fail("toggling did not pause the burner")
			gas_at_pause = _stock(GameState.RESOURCE_GAS)
			energy_at_pause = _stock(GameState.RESOURCE_ENERGY)
			stage = 2
			elapsed = 0.0
			return false
		2:
			# --- C. paused, it does nothing -------------------------------
			if elapsed < 1.5:
				return false
			if _stock(GameState.RESOURCE_ENERGY) != energy_at_pause:
				return _fail("a paused burner made %d more energy" \
					% (_stock(GameState.RESOURCE_ENERGY) - energy_at_pause))
			if _stock(GameState.RESOURCE_GAS) != gas_at_pause:
				return _fail("a paused burner consumed %d gas" \
					% (gas_at_pause - _stock(GameState.RESOURCE_GAS)))
			print("paused for %.1fs: no gas burned, no energy made" % elapsed)

			# --- D. resuming works again ----------------------------------
			if game_state.toggle_building_paused(burner_id):
				return _fail("toggling a paused burner did not resume it")
			stage = 3
			elapsed = 0.0
			return false
		3:
			if elapsed < 1.5:
				return false
			if _stock(GameState.RESOURCE_ENERGY) <= energy_at_pause:
				return _fail("a resumed burner made no further energy")
			print("resumed: energy %d -> %d" \
				% [energy_at_pause, _stock(GameState.RESOURCE_ENERGY)])

			# --- E. the icon reports the action, not the state ------------
			var building: Node = _find_building_node()
			if building == null:
				return _fail("no Building node was spawned for the burner")
			var running_icon: int = controller._building_action_icon(building)
			game_state.set_building_paused(burner_id, true)
			var paused_icon: int = controller._building_action_icon(building)
			game_state.set_building_paused(burner_id, false)
			if running_icon != IconButton.Icon.PAUSE:
				return _fail("a running burner's button does not show the pause glyph")
			if paused_icon != IconButton.Icon.RESUME:
				return _fail("a paused burner's button does not show the resume glyph")
			print("button shows pause while running and resume while stopped")

			print("TEST_GAS_BURNER_PAUSE: PASS")
			quit(0)
			return true
	return false


func _find_building_node() -> Node:
	for node in get_nodes_in_group("buildings"):
		if is_instance_valid(node) and int(node.building_id) == burner_id:
			return node
	return null


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