## Visual test capture engine — boots the entry's "scene" (default main.tscn),
## runs a named scenario or flow, captures viewport PNGs for golden comparison
## or ad-hoc inspection.
##
## Usage:
##   godot --rendering-driver opengl3 --fixed-fps 60 --resolution 960x540 \
##     --path client -s res://tests/visual_capture.gd -- \
##     --scenario atlas_GJ820Bc_Global --output /abs/path
##
##   godot ... -- --flow flow_dialogue --output /abs/path --interval 3
##   godot ... -- --list
##
##   T-1157 (D-255 rewrite): --scenario atlas_matrix --output /abs/path
##   (SR_LIVE=1 SR_PORT=N required — reads tests/atlas_shots.json instead of
##   tests/visual.json's scenarios{}, loops every body/rung combo in ONE Godot
##   boot; goldens key on (body, rung) per the stepped Atlas ladder).
##
## Follows gen_client_fixtures.gd pattern: extends SceneTree, _init -> _run, quit().
## Requires a real rendering driver (not --headless) for shader execution.
extends SceneTree

# Load VisualScenarios explicitly — class_name registry not populated in -s mode.
# Must create an instance: static methods on loaded GDScript resources aren't
# callable via variable (only via class_name, which isn't available in -s mode).
var _scenarios: RefCounted = null

var _output_dir: String = ""
var _scenario: String = ""
var _flow: String = ""
var _interval: float = 3.0
var _list_mode: bool = false
var _config: Dictionary = {}
var _is_live: bool = false


func _init():
	_run.call_deferred()


func _run():  # gdlint:disable=max-returns
	# Parse CLI args (after -- separator)
	_parse_args()

	# Load scenarios script and create instance (class_name not available in -s mode)
	var scenarios_script: GDScript = load("res://tests/visual_scenarios.gd")
	_scenarios = scenarios_script.new()

	# Load config
	_config = _load_config()
	if _config.is_empty():
		push_error("visual_capture: failed to load tests/visual.json")
		quit(1)
		return

	# List mode: print scenario/flow names and exit
	if _list_mode:
		_print_list()
		quit()
		return

	# Validate mode
	if _scenario.is_empty() and _flow.is_empty():
		push_error("visual_capture: specify --scenario NAME or --flow NAME (or --list)")
		quit(1)
		return

	if _output_dir.is_empty():
		push_error("visual_capture: --output DIR is required")
		quit(1)
		return

	# Ensure output directory exists
	DirAccess.make_dir_recursive_absolute(_output_dir)

	# Per-entry overrides (T-1088, design §10.2 — both additive; existing entries
	# without these keys behave byte-identically):
	#   "scene": alternate root scene (default res://scenes/main.tscn)
	#   "env":   env vars set before the scene boots (e.g. SR_AUTOPILOT) — OS-level,
	#            so the scene's _ready() reads them exactly like shell-exported vars;
	#            run-visual has no per-scenario env mechanism, this is it.
	var entry_cfg := _entry_config()
	var env_vars: Dictionary = entry_cfg.get("env", {})
	for env_key: String in env_vars:
		OS.set_environment(env_key, str(env_vars[env_key]))

	# Load root scene (autoloads already initialized from project.godot)
	var scene_path: String = entry_cfg.get("scene", "res://scenes/main.tscn")
	var main_scene = load(scene_path)
	if main_scene == null:
		push_error("visual_capture: failed to load %s" % scene_path)
		quit(1)
		return

	var main_node = main_scene.instantiate()

	# Live mode: configure server port BEFORE main.gd._ready() calls connect_to_sim()
	_is_live = OS.get_environment("SR_LIVE") == "1"
	if _is_live:
		var sim_bridge := root.get_node("/root/SimBridge")
		var port_env := OS.get_environment("SR_PORT")
		if port_env.is_empty():
			push_error("visual_capture: SR_LIVE=1 but SR_PORT not set")
			quit(1)
			return
		sim_bridge.server_port = int(port_env)
		print("visual_capture: live mode — server port %d" % sim_bridge.server_port)

	root.add_child(main_node)

	# Wait for NoiseTexture2D async generation
	var fog_overlay = main_node.get_node_or_null("World/FogOverlay")
	if fog_overlay and not fog_overlay._noise_ready:
		print("visual_capture: waiting for fog noise texture...")
		await fog_overlay.fog_noise_ready
	print("visual_capture: fog noise ready")

	# Set deterministic shader time BEFORE settle frames
	# Autoload globals not available as identifiers in -s mode — use tree path.
	root.get_node("/root/FogState").override_time = 1.0

	# Settle frames (camera smoothing, fog uniform init, UI layout)
	var settle_count: int = _config.get("settle_frames", 30)
	print("visual_capture: settling %d frames..." % settle_count)
	for i in range(settle_count):
		await process_frame

	# Live mode: wait for server connection and first snapshot
	if _is_live:
		var sim_bridge := root.get_node("/root/SimBridge")
		var game_state := root.get_node("/root/GameState")
		print("visual_capture: waiting for server connection...")
		var max_frames := 300  # 5 seconds at 60fps
		var waited := 0
		while sim_bridge.state != sim_bridge.ConnectionState.CONNECTED:
			if sim_bridge.state == sim_bridge.ConnectionState.ERROR:
				push_error("visual_capture: server connection failed")
				quit(1)
				return
			await process_frame
			waited += 1
			if waited >= max_frames:
				push_error("visual_capture: connection timeout after %d frames" % waited)
				quit(1)
				return
		print("visual_capture: connected after %d frames" % waited)
		# Wait for first snapshot from server
		waited = 0
		while game_state.current_tick == 0:
			await process_frame
			waited += 1
			if waited >= max_frames:
				push_error("visual_capture: no snapshot after %d frames" % waited)
				quit(1)
				return
		print(
			"visual_capture: first snapshot tick=%d (%d frames)" % [game_state.current_tick, waited]
		)

	if not _scenario.is_empty():
		await _run_scenario(main_node)
	elif not _flow.is_empty():
		await _run_flow(main_node)

	quit()


func _run_scenario(_main_node: Node) -> void:
	# T-1120: atlas_matrix is not a tests/visual.json scenario entry — it drives
	# its own config (tests/atlas_shots.json) and loops many captures per Godot
	# boot instead of one. Dispatch before the tests/visual.json lookup below so
	# it never needs a (meaningless) scenarios{} entry there.
	if _scenario == "atlas_matrix":
		await _run_atlas_matrix()
		return

	var scenarios: Dictionary = _config.get("scenarios", {})
	if not scenarios.has(_scenario):
		push_error("visual_capture: unknown scenario '%s'" % _scenario)
		quit(1)
		return

	var scenario_cfg: Dictionary = scenarios[_scenario]
	var ticks: int = scenario_cfg.get("ticks", 5)

	print("visual_capture: scenario '%s' — %d ticks" % [_scenario, ticks])

	# Apply scenario setup hook (pass root for autoload access)
	if not _scenarios.apply_setup(_scenario, root):
		push_warning("visual_capture: no setup hook for '%s'" % _scenario)

	# Advance simulation ticks (each process_frame polls one snapshot)
	for i in range(ticks):
		await process_frame

	# Post-tick setup (e.g. zone tint patching)
	_scenarios.post_setup(_scenario, root)

	# Replay snapshot: inject a real server snapshot through the FULL client pipeline.
	# Loads MessagePack bytes (exact wire format from server), decodes via Protocol.gd,
	# then applies through GameState → FogState → shader — same path as live game.
	var replay_path: String = scenario_cfg.get("replay_snapshot", "")
	if not replay_path.is_empty():
		var project_root := ProjectSettings.globalize_path("res://")
		var repo_root := project_root.rstrip("/").get_base_dir()
		var abs_path := repo_root.path_join(replay_path)
		var rf := FileAccess.open(abs_path, FileAccess.READ)
		if rf == null:
			push_error("visual_capture: cannot open replay snapshot %s" % abs_path)
			quit(1)
			return
		var replay_bytes := rf.get_buffer(rf.get_length())
		rf.close()
		# Decode through Protocol.decode_snapshot() — same as live IPC receive path.
		# This exercises: msgpack decode → entity decode → tile_kind→type mapping → etc.
		# class_name `Protocol` isn't resolvable in -s mode (see header note);
		# instantiate the script and call the static decoder on the instance,
		# then free it — the decoded Dictionary is independent of the node.
		var protocol_node: Node = load("res://scripts/protocol/protocol.gd").new()
		var replay_data: Variant = protocol_node.decode_snapshot(replay_bytes)
		protocol_node.free()
		if replay_data == null or not replay_data is Dictionary:
			push_error("visual_capture: Protocol.decode_snapshot failed for %s" % abs_path)
			quit(1)
			return
		print(
			(
				"visual_capture: replaying %s (%d bytes, tick=%s, %d tiles)"
				% [
					replay_path,
					replay_bytes.size(),
					str(replay_data.get("tick", "?")),
					replay_data.get("visible_tiles", []).size()
				]
			)
		)
		var game_state := root.get_node("/root/GameState")
		var fog_state := root.get_node("/root/FogState")
		game_state.apply_snapshot(replay_data)
		fog_state.update_from_state()
		# Extra frames for fog uniform propagation
		for i in range(4):
			await process_frame

	# T-1157 (D-255 rewrite): atlas_* golden scenarios navigate the stepped
	# ladder (visual_scenarios.gd's _setup_atlas_golden_shot) — the fixed tick
	# count above is not a settle guarantee for a live step-canvas fetch (a
	# slow server round-trip can still be in flight after `ticks` frames).
	# Poll StepCanvasRequest.is_pending() the same is_pending()-aware way
	# atlas_agent_driver.gd's _settle_after_intent() does, with the same
	# bounded fallback (never an unbounded await), before capturing. Also logs
	# the view-transform snapshot (T-1157 inventory item 3) right before the
	# capture it describes.
	if _scenario.begins_with("atlas_"):
		await _settle_atlas_viewer_if_pending(root)
		_log_atlas_view_transform(root, _scenario)

	# Extra frames for state propagation + viewport texture lag
	await process_frame
	await process_frame

	# Capture
	await _capture("%s/%s.png" % [_output_dir, _scenario])


## T-1157 (D-255 rewrite) — is_pending()-aware settle for an atlas_* golden,
## matching atlas_agent_driver.gd's own _settle_after_intent() bounded-fallback
## discipline exactly (same SETTLE_MAX_FRAMES bound, same "log and move on
## rather than hang the whole run" behavior on timeout — inventory item 4,
## full-run-restart-on-anomaly, is the CALLER's responsibility: this function
## never retries, it just stops waiting and lets the capture proceed, so a
## caller comparing two runs sees a real discrepancy instead of a silent hang).
const ATLAS_SETTLE_MAX_FRAMES: int = 600


func _settle_atlas_viewer_if_pending(tree_root: Node) -> void:
	var viewer: Variant = _get_atlas_regional_viewer(tree_root)
	if viewer == null:
		return
	var request: Variant = viewer.get_request()
	var waited := 0
	while request.is_pending() and waited < ATLAS_SETTLE_MAX_FRAMES:
		await process_frame
		waited += 1
	if request.is_pending():
		print(
			(
				"visual_capture: atlas settle timed out after %d frames — request still pending"
				% ATLAS_SETTLE_MAX_FRAMES
			)
		)


## T-1157 harness-inventory item 3 (view-transform logging): world_center,
## the held rung, the held canvas extent, and the drawing canvas Node2D's own
## on-screen position/scale — logged at every atlas_* capture so a pixel
## mismatch is root-causable (PR #204's own precedent: this exact log shape
## identified an edge-scroll drift bug by its PAN_SPEED_PX_S*frame_time
## fingerprint) instead of a bare "pixels don't match".
##
## PR #212 review (Tyre finding 1): `footprint_px` previously sourced
## canvas_width/canvas_height off get_current_canvas_summary() — those are the
## held canvas's CELL dimensions (gridunits), not its on-screen PIXEL
## footprint, which is exactly the wrong quantity for a log whose whole job is
## catching a fit-scale-multiplier bug (the T-1192 Global integer-fit ratio,
## PR #204's own drift class). The real on-screen footprint is
## StepCanvasTerrainLayer's own `_footprint_px` — private to that node, so
## rather than reach into it (this cluster's own "no private-field reach"
## discipline — get_current_canvas_summary()'s doc makes the same call for
## `_canvas_ref`), this recomputes the identical value from the SAME public,
## pure function the terrain layer itself calls to produce it
## (StepCanvasTransport.canvas_footprint_px(rung, extent) —
## step_canvas_terrain_layer.gd's own rebuild_from_canvas():
## `_footprint_px = StepCanvasTransport.canvas_footprint_px(rung, new_size)`),
## then multiplies by the SAME canvas_scale already logged here (the T-1192
## Global integer-fit multiplier, 1.0 elsewhere) — matching
## _centered_view_offset()'s own `raw_footprint * scale` pattern for the
## identical "true on-screen size" quantity. canvas_cells is kept alongside
## it (relabeled from the old footprint_px name) since the cell count is
## still useful log context, just correctly named now.
func _log_atlas_view_transform(tree_root: Node, scenario_name: String) -> void:
	var viewer: Variant = _get_atlas_regional_viewer(tree_root)
	if viewer == null:
		return
	var summary: Dictionary = viewer.get_current_canvas_summary()
	var canvas_node: Node2D = viewer.get_node_or_null("StepCanvas")
	var canvas_pos: Vector2 = canvas_node.position if canvas_node else Vector2.ZERO
	var canvas_scale: Vector2 = canvas_node.scale if canvas_node else Vector2.ONE
	var rung: String = str(summary.get("rung", ""))
	var held_extent_raw: Variant = summary.get("held_extent", [0, 0])
	var extent_cells := Vector2i(int(held_extent_raw[0]), int(held_extent_raw[1]))
	var StepCanvasTransport := load(
		"res://ui/implant/apps/atlas/step_canvas/step_canvas_transport.gd"
	)
	var raw_footprint_px: Vector2 = StepCanvasTransport.canvas_footprint_px(rung, extent_cells)
	var on_screen_footprint_px: Vector2 = raw_footprint_px * canvas_scale
	print(
		(
			(
				"visual_capture: view-transform[%s] rung=%s world_center=%s held_extent=%s "
				+ "canvas_position=%s canvas_scale=%s footprint_px=%s canvas_cells=%dx%d "
				+ "courses=%d runs=%d longest=%.1fpx drawn=%d settlements=%d "
				+ "planes=%s relief_grad=%.2f elev_grad=%.2f"
			)
			% [
				scenario_name,
				rung,
				str(summary.get("world_center", [])),
				str(held_extent_raw),
				str(canvas_pos),
				str(canvas_scale),
				str(on_screen_footprint_px),
				int(summary.get("canvas_width", 0)),
				int(summary.get("canvas_height", 0)),
				int(summary.get("course_count", 0)),
				int(summary.get("runs_built", 0)),
				float(summary.get("longest_run_px", 0.0)),
				int(summary.get("drawn_course_count", 0)),
				int(summary.get("settlement_count", 0)),
				str(summary.get("plane_variety", {})),
				float(summary.get("relief_gradient", 0.0)),
				float(summary.get("elev_gradient", 0.0)),
			]
		)
	)


## Shared "regional" screen -> StepCanvasViewer accessor for the atlas_*
## golden path — mirrors AtlasAgentInterface's own _get_viewer() null-safety
## (app not instantiated, or "regional" not registered yet), returning null
## rather than erroring so callers can no-op cleanly on a non-atlas or
## not-yet-navigated scenario.
func _get_atlas_regional_viewer(tree_root: Node) -> Variant:
	var registry: Node = tree_root.get_node_or_null("/root/ImplantRegistry")
	if registry == null:
		return null
	var app: Variant = registry.get_app_instance("implant/map")
	if app == null:
		return null
	var regional_screen: Variant = app.get_screen("regional")
	if regional_screen == null:
		return null
	return regional_screen.get_viewer()


func _run_flow(_main_node: Node) -> void:
	var flows: Dictionary = _config.get("flows", {})
	if not flows.has(_flow):
		push_error("visual_capture: unknown flow '%s'" % _flow)
		quit(1)
		return

	var flow_cfg: Dictionary = flows[_flow]
	var steps: Array = flow_cfg.get("steps", [])
	var interval: float = flow_cfg.get("interval", _interval)

	print("visual_capture: flow '%s' — %d steps, %.1fs interval" % [_flow, steps.size(), interval])

	# Create output subdirectory for flow frames
	var flow_dir := "%s/%s" % [_output_dir, _flow]
	DirAccess.make_dir_recursive_absolute(flow_dir)

	var manifest_lines: PackedStringArray = []
	var frame_idx: int = 0

	for step in steps:
		if not step is Dictionary:
			continue
		var action: String = step.get("action", "wait")
		var label: String = step.get("label", action)

		# Apply action
		_scenarios.apply_flow_action(action, root)

		# Wait for interval (timer yields back to main loop — frames keep rendering)
		await create_timer(interval).timeout

		# Extra frames for viewport texture to catch up
		await process_frame
		await process_frame

		# Capture frame
		var frame_name := "%s_%03d.png" % [_flow, frame_idx]
		await _capture("%s/%s" % [flow_dir, frame_name])

		# Build manifest line
		var total_seconds: int = int((frame_idx + 1) * interval)
		var timecode := "%d:%02d" % [total_seconds / 60, total_seconds % 60]
		manifest_lines.append("%03d %s %s" % [frame_idx, timecode, label])

		frame_idx += 1

	# Write manifest sidecar
	var manifest_path := "%s/%s_manifest.txt" % [flow_dir, _flow]
	var f := FileAccess.open(manifest_path, FileAccess.WRITE)
	if f:
		f.store_string("\n".join(manifest_lines) + "\n")
		f.close()
		print("visual_capture: manifest -> %s" % manifest_path)


## T-1157 (D-255 rewrite, supersedes T-1120's zoom/overlay-set matrix): Atlas
## screenshot capture matrix — ONE Godot boot, opens the live Atlas app once
## (same opener as the atlas_gen_open scenario precedent:
## HudGroups.open_app("implant/map")), then loops bodies × rungs from
## tests/atlas_shots.json, capturing a PNG per (body, rung) combo. Rungs
## replace the retired continuous zoom/overlay-set triples per D-255: a
## capture key is now (body, rung), navigated via StepCanvasViewer's real
## jump_to()/is_pending() surface — no set_view()/get_heightmap_texture()
## shim, matching the PR #203 ruling.
##
## Live-mode only (SR_LIVE=1) — every rung's canvas comes from the running
## server over the StepCanvasRequest/Response tagged envelope (D-255(c)), same
## as every other Atlas path. Requires _run()'s live-mode server-connection
## wait to have already completed before this is called.
##
## GOLDEN PROVENANCE (T-1121, carried forward): goldens captured/verified on
## one box are known NOT to port across GPU/font stacks at the current
## tolerance. A golden failing on a different machine is expected drift, not
## a regression, until T-1121 settles the canonical capture box. See the
## _comment_atlas_goldens note in tests/visual.json.
func _run_atlas_matrix() -> void:
	var matrix_cfg := _load_atlas_shots_config()
	if matrix_cfg.is_empty():
		push_error("visual_capture: failed to load tests/atlas_shots.json")
		quit(1)
		return

	var bodies: Array = matrix_cfg.get("bodies", [])
	var shots: Array = matrix_cfg.get("shots", [])
	if bodies.is_empty() or shots.is_empty():
		push_error("visual_capture: tests/atlas_shots.json has no bodies/shots")
		quit(1)
		return

	var body_lookup: Dictionary = {}
	for b: Dictionary in bodies:
		body_lookup[str(b.get("body_id", ""))] = b

	print(
		(
			"visual_capture: atlas_matrix — %d bodies, %d shots, output %s"
			% [bodies.size(), shots.size(), _output_dir]
		)
	)

	# Open the Atlas the same way a player would (precedent: atlas_gen_open
	# scenario, visual_scenarios.gd) — HudGroups is the production opener.
	var hud_groups: Node = root.get_node("/root/HudGroups")
	var registry: Node = root.get_node("/root/ImplantRegistry")
	hud_groups.open_app("implant/map")
	var app: Variant = registry.get_app_instance("implant/map")
	if app == null:
		push_error("visual_capture: atlas app not instantiated")
		quit(1)
		return

	# First body establishes the "regional" screen via nav.push (matches the
	# production entry path — SystemScreen -> nav.push("regional", ...), the
	# same AtlasApp._on_body_selected() tail every real click reaches).
	# Subsequent bodies call RegionalScreen.enter() DIRECTLY instead of
	# nav.push/replace: ImplantApp._on_screen_changed() only calls enter() when
	# the screen id CHANGES (`if _current_screen_id != new_id`), so pushing or
	# replacing "regional" -> "regional" again for body #2 onward would be a
	# silent no-op that leaves the viewer showing body #1 (found via reading
	# implant_app.gd — not previously documented in the recon blueprint).
	var first_body_id: String = str(shots[0].get("body_id", ""))
	var first_body: Dictionary = body_lookup.get(first_body_id, {})
	app.nav.push("regional", {"body": first_body, "system": _system_dict_for(first_body)})
	var viewer: Variant = app._regional_screen._viewer
	if viewer == null:
		push_error("visual_capture: regional screen has no viewer")
		quit(1)
		return

	var current_body_id: String = ""

	for shot: Dictionary in shots:
		var body_id: String = str(shot.get("body_id", ""))
		var body: Dictionary = body_lookup.get(body_id, {})
		if body.is_empty():
			push_warning("visual_capture: shot references unknown body_id '%s'" % body_id)
			continue

		# Only re-enter (reload the Global canvas fresh) when the body
		# actually changes — shots are grouped per-body in atlas_shots.json,
		# so this only fires once per body, not once per shot. enter() always
		# lands on Global (rung 0, D-255(a)); each shot's own rung (below)
		# then navigates from there.
		if body_id != current_body_id:
			current_body_id = body_id
			app._regional_screen.enter({"body": body, "system": _system_dict_for(body)})
			await _settle_atlas_viewer_if_pending(root)

		# Apply overlay set: clear every gen_dw_* toggle, then enable this
		# shot's own set.
		_apply_overlay_set(viewer, shot.get("overlays", []))

		# Navigate to this shot's rung. "Global" needs no jump — enter()/the
		# body-change branch above already landed on it. Every other rung
		# uses jump_to()'s fixed-center revisit seam at world-metre ZERO (the
		# center of every body's own region grid, D-255(a)) — a literal,
		# reproducible point rather than a cursor-anchored derivation.
		var rung: String = str(shot.get("rung", "Global"))
		if rung != "Global":
			viewer.jump_to(Vector2.ZERO, rung)
			await _settle_atlas_viewer_if_pending(root)

		await process_frame
		await process_frame

		var filename: String = str(shot.get("filename", ""))
		if filename.is_empty():
			push_warning("visual_capture: shot for '%s' has no filename, skipping" % body_id)
			continue
		_log_atlas_view_transform(root, filename)
		await _capture("%s/%s" % [_output_dir, filename])

	print("visual_capture: atlas_matrix done — %d shots captured" % shots.size())


## Build the {system_id, proper_name} dict RegionalScreen.enter()/
## StepCanvasViewer.enter() expects, from an atlas_shots.json body entry
## (which already carries system_id/system_proper_name inline — no separate
## system lookup needed).
func _system_dict_for(body: Dictionary) -> Dictionary:
	return {
		"system_id": str(body.get("system_id", "")),
		"proper_name": str(body.get("system_proper_name", "")),
	}


## Clear every toggleable overlay (StepCanvasViewer's OVERLAY_DEFS — the three
## gen_dw_* region-ramp colorizers, D-255 post-stepped vocabulary) then enable
## exactly the requested set.
func _apply_overlay_set(viewer: Variant, overlay_ids: Array) -> void:
	for def: Dictionary in viewer.get_overlay_defs():
		var overlay_id: String = str(def.get("id", ""))
		if str(def.get("group", "")) == "toggle":
			viewer.set_overlay_visible(overlay_id, overlay_ids.has(overlay_id))
	for overlay_id: String in overlay_ids:
		viewer.set_overlay_visible(overlay_id, true)


func _capture(path: String) -> void:
	# Wait for GPU to finish rendering current frame
	await RenderingServer.frame_post_draw

	var image := root.get_viewport().get_texture().get_image()
	if image == null:
		push_error("visual_capture: viewport image is null — GPU rendering may not be available")
		quit(1)
		return

	var err := image.save_png(path)
	if err != OK:
		push_error("visual_capture: failed to save PNG to %s (error %d)" % [path, err])
		quit(1)
		return

	print("visual_capture: captured -> %s (%dx%d)" % [path, image.get_width(), image.get_height()])


## Config entry for the active scenario or flow ({} when the name is unknown —
## the mode runners report that error themselves).
func _entry_config() -> Dictionary:
	var section: Dictionary = {}
	if not _scenario.is_empty():
		section = _config.get("scenarios", {})
		return section.get(_scenario, {})
	if not _flow.is_empty():
		section = _config.get("flows", {})
		return section.get(_flow, {})
	return {}


func _load_config() -> Dictionary:
	# Config is at tests/visual.json relative to repo root.
	# Repo root = parent of Godot project root (client/).
	var project_root := ProjectSettings.globalize_path("res://")
	var repo_root := project_root.rstrip("/").get_base_dir()
	var config_path := repo_root.path_join("tests/visual.json")

	var f := FileAccess.open(config_path, FileAccess.READ)
	if f == null:
		push_error("visual_capture: cannot open %s" % config_path)
		return {}

	var json_text := f.get_as_text()
	f.close()

	var parsed = JSON.parse_string(json_text)
	if parsed == null or not parsed is Dictionary:
		push_error("visual_capture: invalid JSON in %s" % config_path)
		return {}

	return parsed


## T-1120: atlas_shots.json — same load shape as _load_config() (tests/visual.json),
## a sibling file in the same tests/ directory, so the repo_root derivation is
## identical. Kept as a separate function (not folded into _load_config()) since
## the two files have unrelated schemas — merging them would make _config's
## Dictionary shape ambiguous depending on which mode is active.
func _load_atlas_shots_config() -> Dictionary:
	var project_root := ProjectSettings.globalize_path("res://")
	var repo_root := project_root.rstrip("/").get_base_dir()
	var config_path := repo_root.path_join("tests/atlas_shots.json")

	var f := FileAccess.open(config_path, FileAccess.READ)
	if f == null:
		push_error("visual_capture: cannot open %s" % config_path)
		return {}

	var json_text := f.get_as_text()
	f.close()

	var parsed = JSON.parse_string(json_text)
	if parsed == null or not parsed is Dictionary:
		push_error("visual_capture: invalid JSON in %s" % config_path)
		return {}

	return parsed


func _parse_args() -> void:
	var args := OS.get_cmdline_user_args()
	var i := 0
	while i < args.size():
		match args[i]:
			"--scenario":
				i += 1
				if i < args.size():
					_scenario = args[i]
			"--flow":
				i += 1
				if i < args.size():
					_flow = args[i]
			"--output":
				i += 1
				if i < args.size():
					_output_dir = args[i]
			"--interval":
				i += 1
				if i < args.size():
					_interval = float(args[i])
			"--list":
				_list_mode = true
			_:
				push_warning("visual_capture: unknown arg '%s'" % args[i])
		i += 1


func _print_list() -> void:
	var scenarios: Dictionary = _config.get("scenarios", {})
	var flows: Dictionary = _config.get("flows", {})
	print("scenarios:")
	for name in scenarios:
		# Skip "_"-prefixed comment keys and any non-Dictionary value — a bare
		# string here crashed --list once (PR #180: a provenance _comment key
		# placed inside scenarios{}; now top-level, but stay robust).
		if String(name).begins_with("_") or not (scenarios[name] is Dictionary):
			continue
		var desc: String = scenarios[name].get("description", "")
		print("  %s — %s" % [name, desc])
	# T-1157: atlas_matrix isn't a tests/visual.json scenarios{} entry (it reads
	# tests/atlas_shots.json instead — see _run_atlas_matrix()), so it can't be
	# discovered by iterating _config above. Listed by hand so --list stays a
	# complete index of every --scenario value this script accepts.
	print(
		"  atlas_matrix — D-255 stepped Atlas capture matrix, keyed on (body, rung) (tests/atlas_shots.json, live-mode only)"
	)
	print("flows:")
	for name in flows:
		var steps: Array = flows[name].get("steps", [])
		print("  %s — %d steps" % [name, steps.size()])