extends Node
class_name MpAsserts

## The per-step checks. Every one is synchronous and side-effect free: it looks
## at the world as it currently is on THIS peer and returns a verdict.
##
## Most of these are run on both peers for the same step, which is the point —
## the server's authoritative outcome has to be what the client sees too.

var view: MpWorldView
var snapshot: MpSnapshot
var hand: XRToolsFunctionPickup


func setup(p_view: MpWorldView, p_snapshot: MpSnapshot, p_hand: XRToolsFunctionPickup) -> void:
	view = p_view
	snapshot = p_snapshot
	hand = p_hand


## On the server "snapped" means the zone owns the object. On a client the snap
## is server-authoritative and never happens locally, so what must be true there
## is that the replicated object actually sits in the zone.
func snapped(item_name: String, station: String) -> Dictionary:
	var item := view.find(item_name)
	var zone := view.zone_of(station)
	if not item:
		return {"ok": false, "detail": "'%s' does not exist on this peer" % item_name}
	if not zone:
		return {"ok": false, "detail": "station '%s' has no snap zone on this peer" % station}
	var dist := item.global_position.distance_to(zone.global_position)
	var problems: Array[String] = []
	if dist > MpSteps.SNAP_TOLERANCE:
		problems.append("%s is %.3fm from %s's zone (tolerance %.2f)"
			% [item_name, dist, station, MpSteps.SNAP_TOLERANCE])
	if NetworkManager.owns_world():
		if zone.picked_up_object != item:
			problems.append("%s's zone holds %s, not %s" % [station, zone.picked_up_object, item_name])
		elif not item.is_picked_up():
			problems.append("%s's zone claims %s but it has no grab driver (half-snapped)" % [station, item_name])
	if problems.is_empty():
		return {"ok": true, "detail": "%s is snapped into %s; %s" % [item_name, station, view.diag(item, hand)]}
	return {"ok": false, "detail": "%s | %s" % [", ".join(problems), view.diag(item, hand)]}


func dirty(plate_name: String, want_dirty: bool) -> Dictionary:
	var plate := view.find(plate_name)
	if not plate:
		return {"ok": false, "detail": "'%s' does not exist on this peer" % plate_name}
	var pc := plate.get_node_or_null("PlateController")
	if not pc:
		return {"ok": false, "detail": "'%s' has no PlateController" % plate_name}
	if pc.is_dirty != want_dirty:
		return {"ok": false, "detail": "%s.is_dirty is %s, expected %s; %s"
			% [plate_name, pc.is_dirty, want_dirty, view.diag(plate, hand)]}
	return {"ok": true, "detail": "%s.is_dirty == %s as expected" % [plate_name, want_dirty]}


## A consumed object must be gone on EVERY peer, not just the one that consumed it.
func gone(item_name: String) -> Dictionary:
	var item := view.find(item_name)
	if item and is_instance_valid(item):
		return {"ok": false, "detail": "'%s' still exists on this peer at %s (it should have been consumed)"
			% [item_name, item.global_position]}
	return {"ok": true, "detail": "'%s' is gone, as expected" % item_name}


func food_exists(food_id: String) -> Dictionary:
	var item := view.find_by_food_id(food_id)
	if not item:
		return {"ok": false, "detail": "no item with food id '%s' exists on this peer" % food_id}
	return {"ok": true, "detail": "'%s' exists: %s at %s" % [food_id, item.name, item.global_position]}


func plate_contains(plate_name: String, food_id: String) -> Dictionary:
	var plate := view.find(plate_name)
	if not plate:
		return {"ok": false, "detail": "'%s' does not exist on this peer" % plate_name}
	var pc := plate.get_node_or_null("PlateController")
	if not pc:
		return {"ok": false, "detail": "'%s' has no PlateController" % plate_name}
	if not (food_id in pc.contained_ids):
		return {"ok": false, "detail": "%s holds %s, expected it to contain '%s'"
			% [plate_name, str(pc.contained_ids), food_id]}
	return {"ok": true, "detail": "%s contains %s" % [plate_name, str(pc.contained_ids)]}


## Food shown on a plate is a cosmetic child of it, so it has to stay put when
## the plate is picked up and carried. If it drifts, the player sees the burger
## fly off the plate.
func plate_visuals(plate_name: String) -> Dictionary:
	var plate := view.find(plate_name)
	if not plate:
		return {"ok": false, "detail": "'%s' does not exist on this peer" % plate_name}
	var off := snapshot.max_visual_offset(plate)
	if off < 0.0:
		return {"ok": false, "detail": "%s is not showing any food to check" % plate_name}
	if off > MpSnapshot.MAX_VISUAL_OFFSET:
		return {"ok": false, "detail": "%s's food has come off the plate: %.3fm away (limit %.2f). %s"
			% [plate_name, off, MpSnapshot.MAX_VISUAL_OFFSET, snapshot.visual_diag(plate)]}
	return {"ok": true, "detail": "%s's food is still on it (%.3fm from centre). %s"
		% [plate_name, off, snapshot.visual_diag(plate)]}


## A station's progress bar must show the same thing to everyone: visible while
## the station is working, gone once it has finished. Only the world owner runs
## station logic, so a client can only get this right if the display is driven
## from replicated state.
func station_bar(station_name: String, want_visible: bool) -> Dictionary:
	var station := view.find(station_name)
	if not station:
		return {"ok": false, "detail": "'%s' does not exist on this peer" % station_name}
	var bar := station.get_node_or_null("ProgressBar3D") as ProgressBar3D
	if not bar:
		return {"ok": false, "detail": "%s has no ProgressBar3D" % station_name}
	var shown := bar.is_bar_visible()
	var detail := "%s bar visible=%s progress=%.0f%%" % [station_name, shown, bar.get_progress()]
	if "cooking_result" in station:
		detail += " cooking='%s'" % station.cooking_result
	if "is_washing" in station:
		detail += " washing=%s" % station.is_washing
	if shown != want_visible:
		return {"ok": false, "detail": "expected %s's bar to be %s, but %s"
			% [station_name, "visible" if want_visible else "hidden", detail]}
	return {"ok": true, "detail": detail}


## A station that has had its object taken away must not still be holding it.
func zone_empty(station_name: String) -> Dictionary:
	var zone := view.zone_of(station_name)
	if not zone:
		return {"ok": false, "detail": "station '%s' has no snap zone on this peer" % station_name}
	if not NetworkManager.owns_world():
		# Client zones are gated off entirely; they never hold anything.
		return {"ok": true, "detail": "%s: client zones are gated, nothing to check" % station_name}
	if is_instance_valid(zone.picked_up_object):
		return {"ok": false, "detail": "%s's zone still holds %s after it was taken away"
			% [station_name, zone.picked_up_object]}
	return {"ok": true, "detail": "%s's zone is empty" % station_name}