extends SceneTree
const E = preload("res://world/owniverse/math/exact.gd")
const Clock = preload("res://world/owniverse/simulation_time.gd")
const Fixture = preload("res://tests/fixtures/civilization_benchmark.gd")
var checks: int = 0
var failures: int = 0

func _initialize(): call_deferred("run")
func check(condition: bool, message: String):
    checks += 1
    if not condition:
        failures += 1
        push_error(message)
func fixture():
    var world = load("res://world/owniverse/owniverse.gd").new()
    world.catalog.load_definitions(root.get_node("Global").OwniverseEntities)
    Fixture.seed(world, root.get_node("Global"))
    return world
func dispose(world):
    for entity in world.catalog.entities.values(): entity.free()
    world.free()

func run():
    Engine.max_fps = 0
    var direct = fixture()
    var sliced = fixture()
    for delta in [1.0 / 60.0, 0.133333333333]:
        direct.evolute(delta)
        var clock: Dictionary = Clock.advance(sliced.state.time, delta, sliced.speed)
        var budget = load("res://world/owniverse/frame_budget.gd").new(self, 1)
        await sliced.evolution.evolute_to_datetime(clock.datetime, clock, budget)
        check(E.eq(direct.state, sliced.state), "Sliced transaction exactly matches uninterrupted evolution")
    dispose(direct)
    dispose(sliced)
    direct = fixture()
    sliced = fixture()
    var initial_h: Variant = sliced.state.amount.H
    sliced.evolute_frame(0.2, self)
    check(sliced.frame_busy, "Heavy transaction yields before publishing")
    check(E.eq(sliced.state.time.year, 0), "Published clock stays at completed transaction")
    check(E.eq(sliced.display_clock().year, Clock.advance({"datetime": 0, "year": 0}, 0.2, sliced.speed).year), "Display clock advances independently of the heavy transaction")
    check(sliced.request_production("H", 1, true), "Production requested during a frame is queued")
    check(sliced.frame_checkpoint().productions.size() == 1, "Queued production remains part of the save checkpoint")
    check(E.eq(sliced.state.amount.H, initial_h), "Player action waits for transaction commit")
    sliced.evolute_frame(0.01, self)
    var requested: Dictionary = sliced.frame_clock.duplicate()
    sliced.speed = 3
    check(sliced.speed == 3 and sliced.state.speed == 6, "Speed change is visible and cannot mutate an unfinished transaction")
    while sliced.frame_busy or sliced.production_queue_busy: await process_frame
    direct.evolute(0.2)
    direct.production.produce_hs("H", 1)
    direct.speed = 3
    check(E.eq(direct.state, sliced.state), "Queued action and speed change survive publication")
    sliced.evolute_frame(0.001, self)
    check(not sliced.frame_busy, "Speed change does not bypass real-time cadence")
    sliced.evolute_frame(0.189, self)
    var second_clock: Dictionary = Clock.advance(Clock.advance(requested, 0.001, 3), 0.189, 3)
    var active: Dictionary = sliced.frame_active_clock.duplicate()
    while sliced.frame_busy or sliced.production_queue_busy: await process_frame
    direct.evolution.evolute_to_datetime(active.datetime, active)
    check(E.eq(direct.state, sliced.state), "Bounded frame transaction matches its exact target clock")
    check(E.eq(sliced.frame_clock, second_clock), "All elapsed time during a busy frame remains in the requested clock")
    check(sliced.frame_commits == 2, "Only complete simulation states are committed")
    dispose(direct)
    dispose(sliced)
    var original = fixture()
    original.evolute_frame(0.2, self)
    original.request_production("H", 123, true)
    original.evolute_frame(0.01, self)
    original.speed = 3
    var checkpoint: Dictionary = E.decode(E.encode(original.frame_checkpoint()))
    var published: Dictionary = E.decode(E.encode(original.state))
    var expected_clock: Dictionary = original.frame_active_clock.duplicate()
    dispose(original)
    for frame in 3: await process_frame
    var resumed = fixture()
    var expected = fixture()
    resumed.state = published.duplicate(true)
    expected.state = published.duplicate(true)
    resumed.restore_frame_checkpoint(checkpoint)
    resumed.evolute_frame(0.0, self)
    while resumed.frame_busy or resumed.production_queue_busy: await process_frame
    expected.evolution.evolute_to_datetime(expected_clock.datetime, expected_clock)
    expected.production.produce_hs("H", 123)
    expected.speed = 3
    check(E.eq(expected.state, resumed.state), "Checkpoint recomputes interrupted transaction and preserves queued production")
    check(E.eq(resumed.frame_clock, checkpoint.requested_clock), "Checkpoint preserves all requested elapsed time")
    dispose(resumed)
    dispose(expected)
    var cancelled = fixture()
    cancelled.evolute_frame(0.2, self)
    check(cancelled.frame_busy, "Cancellation fixture has suspended work")
    var budget_ref: RefCounted = cancelled.frame_budget
    dispose(cancelled)
    for frame in 3: await process_frame
    check(budget_ref.cancelled, "Resetting the world cancels suspended work without publishing")
    var invalid = fixture()
    var before: Dictionary = invalid.state.duplicate(true)
    invalid.evolute_frame(1e308, self)
    invalid.evolute(1e308)
    check(not invalid.frame_busy and invalid.frame_clock.is_empty() and E.eq(before, invalid.state), "Overflowing elapsed float cannot enter either clock API")
    dispose(invalid)
    for selected_speed in range(1, 7):
        var scheduled = fixture()
        scheduled.speed = selected_speed
        scheduled.evolute_frame(0.1, self)
        check(not scheduled.frame_busy and scheduled.frame_commits == 0, "Wait for a full step at speed %d" % selected_speed)
        scheduled.evolute_frame(0.1, self)
        while scheduled.frame_busy: await process_frame
        var cadence_clock: Dictionary = Clock.advance({"datetime": 0, "year": 0}, 0.2, selected_speed)
        check(scheduled.frame_commits == 1 and E.eq(scheduled.state.time, cadence_clock), "One complete 0.2 second cycle at speed %d" % selected_speed)
        scheduled.evolute_frame(0.0, self)
        check(not scheduled.frame_busy and scheduled.frame_commits == 1, "No extra cycle without elapsed time")
        dispose(scheduled)
    var behind = fixture()
    behind.evolute_frame(1.0, self)
    while behind.frame_busy: await process_frame
    check(E.eq(behind.state.time.datetime, 100000) and E.eq(behind.state.time, behind.frame_clock), "Delayed start consumes all elapsed time in one cycle")
    behind.evolute_frame(0.0, self)
    check(behind.frame_commits == 1 and not behind.frame_busy, "Consumed interval cannot be processed twice")
    var next_interval: float = behind.frame_step_seconds + 0.03
    behind.evolute_frame(next_interval, self)
    var remained_busy: bool = behind.frame_busy
    if remained_busy: behind.evolute_frame(0.53, self)
    var pending_clock: Dictionary = behind.frame_clock.duplicate()
    if remained_busy:
        var expected_active: Dictionary = Clock.advance({"datetime": 100000, "year": 100000}, next_interval, behind.speed)
        check(E.eq(behind.frame_active_clock, expected_active), "Busy transaction reserves its original target")
    while behind.frame_busy: await process_frame
    if remained_busy:
        check(E.eq(behind.state.time, behind.frame_active_clock), "Busy transaction keeps its original target")
        behind.evolute_frame(0.0, self)
        while behind.frame_busy: await process_frame
        check(E.eq(behind.state.time, pending_clock), "Next cycle consumes all time accumulated during computation")
    else:
        check(E.eq(behind.state.time, pending_clock), "Completed transaction publishes the full requested interval")
    dispose(behind)
    print("Frame evolution: %d checks, %d failures" % [checks, failures])
    quit(1 if failures else 0)