extends SceneTree
## Paired, read-only throughput benchmark for adaptive 5/4/3/2 Hz cadence.
const E = preload("res://world/owniverse/math/exact.gd")
const SAVE_PATHS: Array[String] = [
	"res://tests/artifacts/all_objects_speed6.adventure.json",
	"res://tests/artifacts/many_objects_fragmented_stars_cycle.adventure.json"
]
const RESULT_PATH := "res://tests/artifacts/dynamic_cadence_results.json"
var cycles: int = 40
var repeats: int = 2

func _initialize() -> void:
	call_deferred("run")

func restore_json_integers(value):
	if value is float and value == floorf(value) and absf(value) <= 9007199254740991:
		return int(value)
	if value is Dictionary:
		for key in value: value[key] = restore_json_integers(value[key])
	elif value is Array:
		for i in value.size(): value[i] = restore_json_integers(value[i])
	return value

func create_world(initial: Dictionary, use_adaptive_cadence: bool):
	var world = load("res://world/owniverse/owniverse.gd").new()
	world.catalog.load_definitions(root.get_node("Global").OwniverseEntities)
	world.state = initial.duplicate(true)
	world.speed = 6
	world.adaptive_cadence = use_adaptive_cadence
	world.frame_step_seconds = 0.2
	world.cadence_level = 0
	return world

func dispose(world) -> void:
	for entity in world.catalog.entities.values(): entity.free()
	world.free()

func measure(initial: Dictionary, adaptive: bool, save_name: String, repeat_index: int) -> Dictionary:
	var world = create_world(initial, adaptive)
	var elapsed_usec: int = 0
	var requested_seconds: float = 0.0
	var step_counts: Dictionary = {}
	var samples: Array[float] = []
	var initial_clock: Variant = world.state.time.datetime
	for i in cycles:
		var step: float = world.frame_step_seconds
		step_counts[str(step)] = int(step_counts.get(str(step), 0)) + 1
		requested_seconds += step
		var started: int = Time.get_ticks_usec()
		world.evolute(step)
		var usec: int = Time.get_ticks_usec() - started
		elapsed_usec += usec
		samples.append(float(usec) / 1000.0)
	var applied_years: Variant = E.subtract(world.state.time.datetime, initial_clock)
	var expected_years: float = requested_seconds * 100000.0
	assert(absf(E.approx(applied_years) - expected_years) <= maxf(1.0, expected_years * 1e-10), "Clock advance differs from accumulated cadence interval")
	var validation: String = root.get_node("SaveManager").validate_data({
		"format_version": 6,
		"app_version": "0.7.0",
		"ui": {"current_page": 0},
		"state": world.state
	})
	assert(validation.is_empty(), validation)
	samples.sort()
	var result: Dictionary = {
		"save": save_name,
		"mode": "adaptive_5_4_3_2" if adaptive else "fixed_5",
		"repeat": repeat_index,
		"cycles": cycles,
		"mean_ms_per_cycle": float(elapsed_usec) / (cycles * 1000.0),
		"p95_ms": samples[int(ceil(samples.size() * 0.95)) - 1],
		"max_ms": samples.back(),
		"cpu_cycles_per_second": float(cycles) * 1000000.0 / elapsed_usec,
		"simulated_seconds_per_cpu_second": requested_seconds * 1000000.0 / elapsed_usec,
		"requested_simulation_seconds": requested_seconds,
		"applied_game_years": E.fixed(applied_years),
		"cadence_steps": step_counts,
		"final_cadence_hz": 1.0 / world.frame_step_seconds,
		"final_adaptive_quality": world.adaptive_quality
	}
	print("CADENCE_RESULT ", JSON.stringify(result))
	dispose(world)
	return result

func run() -> void:
	for arg in OS.get_cmdline_user_args():
		if arg.begins_with("cycles="): cycles = maxi(1, arg.trim_prefix("cycles=").to_int())
		if arg.begins_with("repeats="): repeats = maxi(1, arg.trim_prefix("repeats=").to_int())
	var inputs: Dictionary = {}
	for path in SAVE_PATHS:
		var parsed = JSON.parse_string(FileAccess.get_file_as_string(path))
		assert(parsed is Dictionary and parsed.get("format_version") == 6, "Invalid benchmark save: " + path)
		var payload: Dictionary = E.decode(restore_json_integers(parsed))
		var validation: String = root.get_node("SaveManager").validate_data(payload)
		assert(validation.is_empty(), validation)
		inputs[path.get_file()] = payload.state
	var results: Array[Dictionary] = []
	for save_name in inputs:
		var initial: Dictionary = inputs[save_name]
		# Alternate order to limit machine warm-up and thermal bias.
		for repeat_index in repeats:
			if repeat_index % 2 == 0:
				results.append(measure(initial, false, save_name, repeat_index))
				results.append(measure(initial, true, save_name, repeat_index))
			else:
				results.append(measure(initial, true, save_name, repeat_index))
				results.append(measure(initial, false, save_name, repeat_index))
	var output := FileAccess.open(RESULT_PATH, FileAccess.WRITE)
	assert(output != null)
	output.store_string(JSON.stringify({
		"machine": OS.get_model_name(),
		"godot": Engine.get_version_info(),
		"speed": 6,
		"cycles_per_run": cycles,
		"repeats": repeats,
		"input_saves_unchanged": true,
		"results": results
	}, "\t", true, true))
	output.close()
	print("Wrote paired cadence results: ", RESULT_PATH)
	quit()