transcience/tests/unit/test_character_store.gd

extends GutTest
## Characters and their persistence. These matter more than most tests here:
## the whole point of a character is that it survives, and losing one to a bug
## is not something a player can be compensated for.

var store: CharacterStore
const ACC := 1234567890123
const OTHER := 9876543210987


func before_each() -> void:
	# A real file in a throwaway location, so the JSON round trip is exercised
	# rather than mocked -- serialisation is exactly where this would break.
	store = CharacterStore.new("user://test_characters_%d.json" % randi())
	store.load_from_disk()


func after_each() -> void:
	DirAccess.remove_absolute(ProjectSettings.globalize_path(store._path))


func test_a_new_account_has_nothing() -> void:
	assert_eq(store.characters_for(ACC).size(), 0)
	assert_null(store.last_played(ACC))
	assert_true(store.can_create(ACC))


func test_creating_and_finding_a_character() -> void:
	var c := store.create_character(ACC, "Ada")
	assert_not_null(c)
	assert_eq(c.display_name, "Ada")
	assert_eq(c.level, Progression.START_LEVEL)
	assert_eq(c.max_hp(), SimConfig.PLAYER_MAX_HP)
	assert_true(c.active)
	assert_eq(store.get_character(ACC, c.id).id, c.id)


func test_accounts_are_isolated() -> void:
	var mine := store.create_character(ACC, "Mine")
	store.create_character(OTHER, "Theirs")
	assert_eq(store.characters_for(ACC).size(), 1)
	assert_null(store.get_character(OTHER, mine.id),
		"one account must never see another's characters")


func test_the_living_character_limit() -> void:
	for i in CharacterStore.MAX_ACTIVE:
		assert_not_null(store.create_character(ACC, "c%d" % i))
	assert_false(store.can_create(ACC))
	assert_null(store.create_character(ACC, "one too many"))


## The reason the cap counts living characters only: five deaths must not lock
## a player out of their own account permanently.
func test_retired_characters_do_not_occupy_a_slot() -> void:
	var first := store.create_character(ACC, "doomed")
	for i in CharacterStore.MAX_ACTIVE - 1:
		store.create_character(ACC, "c%d" % i)
	assert_false(store.can_create(ACC))
	store.retire_character(ACC, first.id)
	assert_true(store.can_create(ACC), "a death should free the slot it held")
	assert_eq(store.characters_for(ACC).size(), CharacterStore.MAX_ACTIVE,
		"but the record itself must still be there")


func test_death_retires_rather_than_deletes() -> void:
	var c := store.create_character(ACC, "Grace")
	store.retire_character(ACC, c.id)
	var found := store.get_character(ACC, c.id)
	assert_not_null(found, "the record is kept for archival")
	assert_false(found.active)
	assert_gt(found.died_unix, 0, "and records when it happened")


func test_last_played_prefers_the_last_one_and_skips_the_dead() -> void:
	var a := store.create_character(ACC, "A")
	var b := store.create_character(ACC, "B")
	store.set_last_played(ACC, a.id)
	assert_eq(store.last_played(ACC).id, a.id)
	store.retire_character(ACC, a.id)
	assert_eq(store.last_played(ACC).id, b.id,
		"a dead character must not be auto-selected on login")


func test_everything_survives_a_save_and_reload() -> void:
	var c := store.create_character(ACC, "Persistent")
	store.grant_xp(ACC, c.id, Progression.xp_to_next(1) + 5)
	store.set_last_played(ACC, c.id)
	var dead := store.create_character(ACC, "Departed")
	store.retire_character(ACC, dead.id)

	var reloaded := CharacterStore.new(store._path)
	assert_true(reloaded.load_from_disk())
	var got := reloaded.get_character(ACC, c.id)
	assert_not_null(got, "the character survived the round trip")
	assert_eq(got.display_name, "Persistent")
	assert_eq(got.level, 2)
	assert_eq(got.colour.to_html(false), c.colour.to_html(false))
	assert_eq(reloaded.last_played(ACC).id, c.id)
	assert_false(reloaded.get_character(ACC, dead.id).active,
		"and so did the fact that one of them died")


## Account ids are 64-bit; JSON numbers are doubles and would round them. They
## are written as decimal strings for exactly this reason.
func test_large_account_ids_survive_the_round_trip() -> void:
	var big := 9007199254740993
	store.create_character(big, "Precise")
	var reloaded := CharacterStore.new(store._path)
	reloaded.load_from_disk()
	assert_eq(reloaded.characters_for(big).size(), 1,
		"a 64-bit account id must not be mangled by JSON")


func test_a_corrupt_file_is_refused_rather_than_overwritten() -> void:
	assert_not_null(store.create_character(ACC, "Valuable"))
	var f := FileAccess.open(store._path, FileAccess.WRITE)
	f.store_string("{ this is not json")
	f.close()
	var reloaded := CharacterStore.new(store._path)
	assert_false(reloaded.load_from_disk(),
		"a bad file must fail loudly; silently starting empty would then " +
		"save over every character on the next write")


func test_granting_experience_reports_levels_gained() -> void:
	var c := store.create_character(ACC, "Riser")
	assert_eq(store.grant_xp(ACC, c.id, 1), 0, "not enough for a level")
	assert_gte(store.grant_xp(ACC, c.id, Progression.total_xp_for_level(3)), 1,
		"crossing a threshold reports the levels")
	var after := store.get_character(ACC, c.id)
	assert_eq(after.level, Progression.level_for_xp(after.total_xp),
		"level and experience must never disagree")


func test_a_dead_character_earns_nothing() -> void:
	var c := store.create_character(ACC, "Late")
	store.retire_character(ACC, c.id)
	store.grant_xp(ACC, c.id, 5000)
	assert_eq(store.get_character(ACC, c.id).total_xp, 0)


## Names are shown to other players, so they are clamped at the boundary rather
## than trusted anywhere downstream.
func test_names_are_sanitised() -> void:
	assert_eq(Character.sanitize_name("   "), "adventurer", "blank names get a default")
	assert_lte(Character.sanitize_name("x".repeat(500)).length(), Character.MAX_NAME)
	var with_control := "ab" + String.chr(7) + String.chr(10) + "cd"
	assert_eq(Character.sanitize_name(with_control), "abcd",
		"control characters would let a name break the HUD's layout")


## The suggested name exists so the create field is never blank. It only has to
## be non-empty and survive sanitising -- it is a starting point, not an
## identity.
func test_suggested_names_are_usable() -> void:
	var rng := RandomNumberGenerator.new()
	rng.seed = 3
	for _i in 50:
		var n := Character.random_name(rng)
		assert_false(n.is_empty())
		assert_lte(n.length(), Character.MAX_NAME)
		assert_eq(Character.sanitize_name(n), n,
			"a suggestion must survive the sanitiser unchanged")


func test_suggested_names_vary() -> void:
	var rng := RandomNumberGenerator.new()
	rng.seed = 9
	var seen := {}
	for _i in 40:
		seen[Character.random_name(rng)] = true
	assert_gt(seen.size(), 10, "a fixed suggestion would be worse than none")


## Inventories live on the character, which is what makes them survive a
## restart, a character swap and a walk into a dungeon.
func test_the_inventory_survives_a_save_and_reload() -> void:
	var c := store.create_character(ACC, "Packrat")
	var carried: Array[StringName] = [Items.HEALTH_POTION, Items.NONE, Items.WARDENS_RATION]
	store.set_inventory(ACC, c.id, carried)

	var reloaded := CharacterStore.new(store._path)
	assert_true(reloaded.load_from_disk())
	var got := reloaded.get_character(ACC, c.id)
	assert_eq(got.inventory.size(), SimConfig.INVENTORY_SLOTS)
	assert_eq(got.inventory[0], Items.HEALTH_POTION)
	assert_eq(got.inventory[1], Items.NONE)
	assert_eq(got.inventory[2], Items.WARDENS_RATION)


## A save file written by a build that had an item this one does not must still
## load -- as an empty slot, never as a different item.
func test_an_unknown_item_in_a_save_file_becomes_an_empty_slot() -> void:
	var restored := Character.from_dict({
		"id": "x", "name": "Old", "xp": 0,
		"inventory": ["health_potion", "phlogiston"],
	})
	assert_eq(restored.inventory[0], Items.HEALTH_POTION)
	assert_eq(restored.inventory[1], Items.NONE)


func test_a_character_from_before_inventories_existed_still_loads() -> void:
	var restored := Character.from_dict({"id": "y", "name": "Legacy", "xp": 500})
	assert_eq(restored.inventory.size(), SimConfig.INVENTORY_SLOTS)
	assert_eq(restored.display_name, "Legacy")


func test_setting_an_inventory_on_a_missing_character_is_harmless() -> void:
	var nothing: Array[StringName] = [Items.HEALTH_POTION]
	store.set_inventory(ACC, "no-such-id", nothing)
	assert_eq(store.characters_for(ACC).size(), 0)


# --- Upgrades ---------------------------------------------------------------

func test_a_level_banks_a_choice_and_puts_three_on_the_table() -> void:
	var c := store.create_character(ACC, "Riser")
	store.grant_choices(ACC, c.id, 1)
	assert_eq(c.pending_choices, 1)
	assert_eq(c.offer.size(), SimConfig.UPGRADE_CHOICES)


## The offer is rolled once and held. If it regenerated per request, closing and
## reopening the screen would be a free reroll until a legendary appeared.
func test_the_offer_is_stable_until_something_is_taken() -> void:
	var c := store.create_character(ACC, "Picky")
	store.grant_choices(ACC, c.id, 1)
	var first := c.offer.duplicate()
	store.grant_choices(ACC, c.id, 1)
	assert_eq(c.offer, first, "banking another level must not reroll the table")


## Two levels in one run owe two choices. Losing one for doing well is a
## punishment nobody would guess at.
func test_choices_queue() -> void:
	var c := store.create_character(ACC, "Fast")
	store.grant_choices(ACC, c.id, 3)
	assert_eq(c.pending_choices, 3)
	store.take_upgrade(ACC, c.id, 0)
	assert_eq(c.pending_choices, 2)
	assert_eq(c.offer.size(), SimConfig.UPGRADE_CHOICES, "and the next three appear")


func test_taking_an_upgrade_records_it_and_rerolls_the_table() -> void:
	var c := store.create_character(ACC, "Taker")
	store.grant_choices(ACC, c.id, 1)
	var wanted: StringName = c.offer[1]
	var taken := store.take_upgrade(ACC, c.id, 1)
	assert_eq(taken, wanted)
	assert_eq(c.upgrades, [wanted] as Array[StringName])
	assert_eq(c.pending_choices, 0)
	assert_true(c.offer.is_empty(), "nothing pending means nothing on the table")


func test_taking_without_a_pending_choice_is_refused() -> void:
	var c := store.create_character(ACC, "Greedy")
	assert_eq(store.take_upgrade(ACC, c.id, 0), &"")
	assert_eq(c.upgrades.size(), 0)


## The index arrives from a client, so nonsense has to be a refusal rather than
## a crash or a free upgrade.
func test_an_index_outside_the_offer_is_refused() -> void:
	var c := store.create_character(ACC, "Sneaky")
	store.grant_choices(ACC, c.id, 1)
	assert_eq(store.take_upgrade(ACC, c.id, -1), &"")
	assert_eq(store.take_upgrade(ACC, c.id, 99), &"")
	assert_eq(c.pending_choices, 1, "and costs nothing")


func test_a_dead_character_cannot_spend_a_choice() -> void:
	var c := store.create_character(ACC, "Late")
	store.grant_choices(ACC, c.id, 1)
	store.retire_character(ACC, c.id)
	assert_eq(store.take_upgrade(ACC, c.id, 0), &"")


func test_upgrades_and_pending_choices_survive_a_reload() -> void:
	var c := store.create_character(ACC, "Persistent")
	store.grant_choices(ACC, c.id, 2)
	var taken := store.take_upgrade(ACC, c.id, 0)
	var offer := c.offer.duplicate()

	var reloaded := CharacterStore.new(store._path)
	assert_true(reloaded.load_from_disk())
	var got := reloaded.get_character(ACC, c.id)
	assert_eq(got.upgrades, [taken] as Array[StringName])
	assert_eq(got.pending_choices, 1)
	assert_eq(got.offer, offer,
		"the table has to survive a restart, or it is a reroll on every crash")


## Upgrades change what a character IS, so the roster has to show the real
## number rather than the one the level alone implies.
func test_the_roster_health_reflects_the_upgrades_taken() -> void:
	var c := store.create_character(ACC, "Fragile")
	var before := c.max_hp()
	c.upgrades.append(Upgrades.GLASS_CANNON)
	assert_eq(c.max_hp(), before / 2)


## A save written by a build with an upgrade this one lacks must not leave a
## phantom that counts toward the flat damage bonus and does nothing else.
func test_an_unknown_upgrade_in_a_save_is_dropped() -> void:
	var restored := Character.from_dict({
		"id": "z", "name": "Old", "xp": 0,
		"upgrades": ["sniper", "telekinesis"],
		"pending_choices": 2,
		"offer": ["poison", "not_a_thing"],
	})
	assert_eq(restored.upgrades, [Upgrades.SNIPER] as Array[StringName])
	assert_eq(restored.offer, [Upgrades.POISON] as Array[StringName])
	assert_eq(restored.pending_choices, 2)


# --- Deferred writes --------------------------------------------------------
# Two paths a client can trigger at the tick rate -- item moves and experience
# grants -- mark the store dirty instead of writing, and the server flushes once
# per tick. Everything else still writes the moment it happens.

func test_experience_below_a_level_boundary_is_still_written() -> void:
	var c := store.create_character(ACC, "Grinder")
	assert_eq(store.grant_xp(ACC, c.id, 5), 0, "nowhere near a level")
	store.flush()

	var reloaded := CharacterStore.new(store._path)
	assert_true(reloaded.load_from_disk())
	assert_eq(reloaded.get_character(ACC, c.id).total_xp, 5,
		"experience that has not crossed a level is the only record of it: " +
		"level is derived from lifetime xp, so losing the xp loses the level")


func test_a_deferred_inventory_write_lands_on_the_flush() -> void:
	var c := store.create_character(ACC, "Carrier")   # writes immediately
	var bag: Array[StringName] = [Items.HEALTH_POTION, Items.NONE, Items.NONE, Items.NONE]
	store.set_inventory(ACC, c.id, bag, true)

	var before := CharacterStore.new(store._path)
	before.load_from_disk()
	assert_eq(before.get_character(ACC, c.id).inventory[0], Items.NONE,
		"deferred means deferred; the file still holds the older bag")

	store.flush()
	var after := CharacterStore.new(store._path)
	after.load_from_disk()
	assert_eq(after.get_character(ACC, c.id).inventory[0], Items.HEALTH_POTION)


func test_flushing_a_clean_store_writes_nothing() -> void:
	store.create_character(ACC, "Idle")
	var stamp := FileAccess.get_modified_time(store._path)
	store.flush()
	assert_eq(FileAccess.get_modified_time(store._path), stamp,
		"a tick in which nothing happened must not cost a disk write")


func test_an_immediate_write_clears_the_pending_one() -> void:
	var c := store.create_character(ACC, "Mixed")
	store.grant_xp(ACC, c.id, 7)            # dirty, not written
	store.set_last_played(ACC, c.id)        # writes now, and takes the xp with it
	var reloaded := CharacterStore.new(store._path)
	reloaded.load_from_disk()
	assert_eq(reloaded.get_character(ACC, c.id).total_xp, 7)