## T-1150 (PR #191 review, Hoshe 4): atlas_window_request.gd had NO test file
## at all before this — direct coverage of the granularity/min_wl_m staleness
## guard, the n-clamp mirror (Tyre C1), and the old-server-shape default
## disposition. Follows test_atlas_window_viewer.gd's own
## "AtlasWindowRequest — cache reuse" section conventions (same
## instantiation pattern: `AtlasWindowRequest.new(owner_stub)`, `add_child()`
## for the debounce Timer, hand-built response dicts) rather than
## re-inventing a shape.
class_name TestAtlasWindowRequest
extends GdUnitTestSuite

# atlas_window_request.gd has no class_name (review #8 precedent throughout
# this cluster) — preloaded once here, not re-load()ed per test (gdlint
# duplicated-load).
const AtlasWindowRequest := preload("res://ui/implant/apps/atlas/atlas_window_request.gd")


## Build a hand-authored DistrictWindowLayer dict, granularity-aware
## (T-1150, extended T-1152/T-1153 for granularity_v2) — mirrors
## test_atlas_window_viewer.gd's own _mock_window(), with
## granularity/min_wl_m/granularity_v2 added as optional params so callers
## can build any rung's echo shape with one helper.
static func _mock_window(
	center: Vector2i,
	n: int = 2,
	granularity: int = 1,
	min_wl_m: int = 0,
	granularity_v2: String = "District"
) -> Dictionary:
	return {
		"center": [center.x, center.y],
		"n": n,
		"granularity": granularity,
		"min_wl_m": min_wl_m,
		"granularity_v2": granularity_v2,
		"morphology": PackedByteArray([8, 14, 0, 1]),
		"elev_q": PackedByteArray([40, 90, 5, 60]),
		"temp_dc": [120, 95, -32768, 60],
		"moisture_q": PackedByteArray([50, 30, 90, 20]),
		"vegetation": PackedByteArray([2, 1, 6, 3]),
		"glaciation": PackedByteArray([0, 0, 1, 2]),
	}


static func _mock_response(body_id: String, window: Variant) -> Dictionary:
	return {"body_id": body_id, "status": "Ready", "district_window": window}


func _make_request() -> Variant:
	var owner_stub := RefCounted.new()
	var req = auto_free(AtlasWindowRequest.new(owner_stub))
	add_child(req)
	return req


# =============================================================================
# (a) granularity mismatch on the echo -> dropped as stale
# =============================================================================


## The mandatory item-(a) case: request_now() asks at the default district
## granularity (1); a response echoing granularity=4 (quarter) for the SAME
## center/n must be dropped as stale, not accepted — a different rung's
## derive answering a request for a different rung is exactly as stale as a
## mismatched center (T-1150 extends §2's guard to this axis).
func test_on_response_with_mismatched_granularity_is_dropped_as_stale() -> void:
	var req = _make_request()
	req.request_now("GJ380c", Vector2i(2, 2), 2)
	assert_bool(req.is_pending()).is_true()

	var quarter_window: Dictionary = _mock_window(Vector2i(2, 2), 2, 4, 0)
	req.on_response(_mock_response("GJ380c", quarter_window))

	assert_bool(req.is_pending()).override_failure_message(
		"a granularity-mismatched response must be dropped as stale, leaving the district request still pending"
	).is_true()


# =============================================================================
# (a2) granularity_v2 mismatch on the echo -> dropped as stale (T-1152/T-1153,
# the axis the legacy int alone cannot express — Region has no legacy value)
# =============================================================================


## request_now() can now ask for Region explicitly (T-1153's rung-reselect
## caller) — a response echoing "District" for the SAME center/n must be
## dropped as stale, the granularity_v2 twin of test (a) above, and the
## ONLY guard that can catch this specific mismatch (the legacy int is
## DISTRICT_GRANULARITY=1 on BOTH sides here, since Region has no legacy
## representation — see WindowGranularity::legacy_u32()'s doc).
func test_on_response_with_mismatched_granularity_v2_is_dropped_as_stale() -> void:
	var req = _make_request()
	req.request_now("GJ380c", Vector2i(0, 0), 6400, AtlasWindowRequest.GRANULARITY_V2_REGION)
	assert_bool(req.is_pending()).is_true()

	var district_window: Dictionary = _mock_window(Vector2i(0, 0), 6400, 1, 0, "District")
	req.on_response(_mock_response("GJ380c", district_window))

	assert_bool(req.is_pending()).override_failure_message(
		"a granularity_v2-mismatched response (District answering a Region request)"
		+ " must be dropped as stale, leaving the request still pending"
	).is_true()


## The matching case: request_now() asking for Region, answered by a Region
## echo at the SAME (center, n) — must be ACCEPTED and cached under the
## Region key, retrievable on a follow-up request without a new network round
## trip.
func test_on_response_matching_granularity_v2_region_is_accepted_and_cached() -> void:
	var req = _make_request()
	req.request_now("GJ380c", Vector2i(0, 0), 6400, AtlasWindowRequest.GRANULARITY_V2_REGION)
	assert_bool(req.is_pending()).is_true()

	var region_window: Dictionary = _mock_window(Vector2i(0, 0), 6400, 1, 0, "Region")
	req.on_response(_mock_response("GJ380c", region_window))
	assert_bool(req.is_pending()).is_false()

	var received: Array = []
	req.window_ready.connect(func(w: Dictionary) -> void: received.append(w))
	req.request_now("GJ380c", Vector2i(0, 0), 6400, AtlasWindowRequest.GRANULARITY_V2_REGION)
	assert_int(received.size()).override_failure_message(
		"a second Region request at the same (center, n) must hit the cache"
	).is_equal(1)
	assert_bool(req.is_pending()).is_false()


# =============================================================================
# (b) old-server-shape response (no granularity/min_wl_m keys) -> defaults
# =============================================================================


## A response from a hypothetical pre-T-1150 server (or any response whose
## district_window dict simply omits the new keys) must decode granularity
## as district (1) and min_wl_m as 0 via the same defaulting on_response()
## already applies — and since request_now()'s own defaults are identical,
## the response is ACCEPTED, not treated as stale just because two keys are
## missing.
func test_on_response_missing_granularity_and_min_wl_defaults_and_is_accepted() -> void:
	var req = _make_request()
	req.request_now("GJ380c", Vector2i(3, 3), 2)
	assert_bool(req.is_pending()).is_true()

	# Old-shape window: no "granularity"/"min_wl_m" keys at all.
	var old_shape_window := {
		"center": [3, 3],
		"n": 2,
		"morphology": PackedByteArray([8, 14, 0, 1]),
		"elev_q": PackedByteArray([40, 90, 5, 60]),
		"temp_dc": [120, 95, -32768, 60],
		"moisture_q": PackedByteArray([50, 30, 90, 20]),
		"vegetation": PackedByteArray([2, 1, 6, 3]),
		"glaciation": PackedByteArray([0, 0, 1, 2]),
	}
	req.on_response(_mock_response("GJ380c", old_shape_window))

	assert_bool(req.is_pending()).override_failure_message(
		(
			"an old-server-shape response (missing granularity/min_wl_m) must "
			+ "default to district/0 and be ACCEPTED, not dropped as stale"
		)
	).is_false()

	var received: Array = []
	req.window_ready.connect(func(w: Dictionary) -> void: received.append(w))
	# Re-request the same (body, center, n) — must now be a cache hit, proving
	# on_response() actually stored the old-shape window under the
	# district/0 key, not silently discarding it.
	req.request_now("GJ380c", Vector2i(3, 3), 2)
	assert_int(received.size()).is_equal(1)
	assert_bool(req.is_pending()).is_false()


# =============================================================================
# (c) n-clamp mirror (Tyre C1) — quarter n=32 stores clamped n=16
# =============================================================================


## **Item (c) as literally scoped by the ticket** ("the clamp-mirror from
## item 1"): `_clamp_window_n_mirror()` reproduces the server's
## `clamp_window_n(raw_n, granularity)` bit-for-bit, INCLUDING the quarter
## n=32 -> 16 case — pinned directly against the static helper, independent
## of the request/response plumbing (`request_now()` has no public
## "request quarter" entry point today; T-1150 is struct/key plumbing only,
## requesting quarter is T-1153's job — see the class-level docstring on
## `_clamp_window_n_mirror()` for why calling `request_now()` at district
## granularity can never itself exercise the quarter branch: it unconditionally
## resets `_granularity` to district BEFORE clamping, by design, since no
## caller can ask for quarter yet).
func test_clamp_window_n_mirror_matches_server_formula_at_quarter_n32() -> void:
	assert_int(AtlasWindowRequest._clamp_window_n_mirror(32, 4)).is_equal(16)
	# District granularity: the per-axis cap (64) governs, matching the
	# server's clamp_window_n_district_granularity_uses_per_axis_cap test.
	assert_int(AtlasWindowRequest._clamp_window_n_mirror(640, 1)).is_equal(64)
	# Small n well under budget at quarter granularity stays unclamped,
	# matching clamp_window_n_quarter_granularity_leaves_small_n_unclamped.
	assert_int(AtlasWindowRequest._clamp_window_n_mirror(8, 4)).is_equal(8)


## **Item (c), the request/response half:** `request_now()` actually WIRES
## the mirror in (not just defines it) — a request for a district-legal but
## per-axis-oversized `n` (e.g. 640, mirroring the server's own
## `DISTRICT_WINDOW_MAX_N*10` oversized-request test) stores the CLAMPED
## `_n=64`, so a server response echoing the server's OWN clamped n=64 is
## ACCEPTED, not rejected as stale for "not matching" the raw 640 that was
## asked for. This is the exact n-clamp/echo/staleness triangle Tyre C1
## flagged, exercised through the reachable (district) path today; the
## quarter-specific n=32->16 number is pinned by the formula test above since
## no public API can drive quarter through `request_now()` yet.
func test_oversized_n_request_stores_clamped_n_and_accepts_matching_echo() -> void:
	var req = _make_request()
	req.request_now("GJ380c", Vector2i(4, 4), 640)

	assert_int(req._n).override_failure_message(
		(
			"request_now() must mirror the server's clamp_window_n(640, granularity=1) "
			+ "== 64 BEFORE storing _n, not store the raw requested 640"
		)
	).is_equal(64)
	assert_bool(req.is_pending()).is_true()

	# The server's real response for this request echoes n=64 (its own
	# clamp_window_n() result) — must be ACCEPTED, not stale.
	var clamped_echo: Dictionary = _mock_window(Vector2i(4, 4), 64, 1, 0)
	req.on_response(_mock_response("GJ380c", clamped_echo))

	assert_bool(req.is_pending()).override_failure_message(
		(
			"a response echoing the CLAMPED n=64 must be accepted, since _n was "
			+ "already clamped to 64 before the request fired"
		)
	).is_false()


# =============================================================================
# (d) Region clamp mirror (T-1152/T-1153) — mirrors
# server/src/atlas/layer_proxy.rs's clamp_window_n_v2 EXACTLY, including the
# Region branch's bounded halving loop (no closed form, per Dudley's own
# doc — "replicate the loop exactly").
# =============================================================================


## District/Quarter through the v2 mirror must be BYTE-IDENTICAL to the
## legacy mirror — the server's own
## `clamp_window_n_v2_matches_legacy_for_finer_than_district_rungs`
## guarantee, restated client-side.
func test_clamp_window_n_mirror_v2_matches_legacy_for_district_and_quarter() -> void:
	assert_int(
		AtlasWindowRequest._clamp_window_n_mirror_v2(32, AtlasWindowRequest.GRANULARITY_V2_QUARTER)
	).is_equal(AtlasWindowRequest._clamp_window_n_mirror(32, 4))
	assert_int(
		AtlasWindowRequest._clamp_window_n_mirror_v2(640, AtlasWindowRequest.GRANULARITY_V2_DISTRICT)
	).is_equal(AtlasWindowRequest._clamp_window_n_mirror(640, 1))


## The clean Region boundary case: n=6,400 (DISTRICT_WINDOW_MAX_N_REGION,
## the per-axis cap exactly) derives cell_grid_side(6400) = round(6400/100) =
## 64, and 64² = 4,096 = WIRE_CAP_CELLS EXACTLY — the halving loop's `>`
## condition is false at the boundary, so this must clamp to EXACTLY 6,400,
## not halve further. This is the server's own
## `region_per_axis_cap_lands_exactly_on_wire_cap_when_uncontested`-shaped
## boundary (WIRE_CAP_CELLS_SQRT * DISTRICTS_PER_REGION is DERIVED to land
## here exactly, per that constant's own doc).
func test_clamp_window_n_mirror_v2_region_boundary_is_exact() -> void:
	var n: int = AtlasWindowRequest._clamp_window_n_mirror_v2(
		AtlasWindowRequest.SERVER_DISTRICT_WINDOW_MAX_N_REGION, AtlasWindowRequest.GRANULARITY_V2_REGION
	)
	assert_int(n).is_equal(AtlasWindowRequest.SERVER_DISTRICT_WINDOW_MAX_N_REGION)


## Region's per-axis cap: a raw `n` far over DISTRICT_WINDOW_MAX_N_REGION
## (mirroring the server's own `region_request_oversized_n_clamps_and_echoes_clamped_n`
## test's `DISTRICT_WINDOW_MAX_N_REGION * 10` shape) must clamp DOWN — never
## trust the wire — and the result must satisfy BOTH invariants the server's
## own test asserts: `n <= DISTRICT_WINDOW_MAX_N_REGION` AND
## `cell_grid_side(n)^2 <= WIRE_CAP_CELLS`.
func test_clamp_window_n_mirror_v2_region_oversized_n_clamps_within_both_bounds() -> void:
	var oversized: int = AtlasWindowRequest.SERVER_DISTRICT_WINDOW_MAX_N_REGION * 10
	var n: int = AtlasWindowRequest._clamp_window_n_mirror_v2(
		oversized, AtlasWindowRequest.GRANULARITY_V2_REGION
	)
	assert_int(n).override_failure_message(
		"echoed n must be clamped to DISTRICT_WINDOW_MAX_N_REGION, not the raw oversized value"
	).is_less_equal(AtlasWindowRequest.SERVER_DISTRICT_WINDOW_MAX_N_REGION)
	var side: int = AtlasWindowRequest._cell_grid_side_region_mirror(n)
	assert_int(side * side).override_failure_message(
		"clamped cell count must never exceed WIRE_CAP_CELLS at Region granularity either"
	).is_less_equal(AtlasWindowRequest.SERVER_WIRE_CAP_CELLS)


## A REGION request whose derived grid would exceed WIRE_CAP_CELLS (n set so
## cell_grid_side(n) rounds to 65, just over the 64-per-axis wire-size
## ceiling) must actually HALVE — this is the case the boundary test above
## deliberately sits just below, so this one confirms the loop body actually
## fires, not just that its guard conditions are correct at the edges.
func test_clamp_window_n_mirror_v2_region_halves_when_over_wire_cap() -> void:
	# n=6,450 -> cell_grid_side = round(64.5) = 65 (round-half-away-from-zero,
	# matching Rust's f64::round() and GDScript's roundi() for non-negative
	# inputs) -> 65² = 4,225 > WIRE_CAP_CELLS (4,096) -> must halve at least once.
	var n: int = AtlasWindowRequest._clamp_window_n_mirror_v2(
		6450, AtlasWindowRequest.GRANULARITY_V2_REGION
	)
	assert_int(n).override_failure_message(
		"a Region request whose grid exceeds WIRE_CAP_CELLS must be halved down, not left at 6,450"
	).is_less(6450)
	var side: int = AtlasWindowRequest._cell_grid_side_region_mirror(n)
	assert_int(side * side).is_less_equal(AtlasWindowRequest.SERVER_WIRE_CAP_CELLS)


## n smaller than one region (n < 100) must clamp its cell-grid side to a
## minimum of 1 — cell_grid_side_for_window()'s own `.max(1)` — never a
## degenerate 0x0 grid, matching WindowGranularity::cell_grid_side's own
## documented minimum.
func test_cell_grid_side_region_mirror_minimum_is_one() -> void:
	assert_int(AtlasWindowRequest._cell_grid_side_region_mirror(1)).is_equal(1)
	assert_int(AtlasWindowRequest._cell_grid_side_region_mirror(50)).is_equal(1)