extends Node
## HUD visibility group manager (D-170).
##
## Nodes register themselves into groups. When a group's visibility changes,
## all registered nodes show/hide together. This replaces per-panel manual
## hide/show of individual HUD elements.
##
## Groups:
##   "gameplay"  — stance indicator, minimap, health/time, interaction prompts,
##                 cursor renderer, inventory, news ticker, examine display
##   "implant"   — star map, travel planner, GTTR reader, station profile
##   "modal"     — settings, bug report, loading screen, debug console
##   "debug"     — debug overlay, gauntlet HUD, checklist
##   "always"    — nodes that never hide (reserved for future use)
##
## Usage from any node:
##   HudGroups.register(self, "gameplay")
##   HudGroups.show_group("implant")    # shows implant, hides gameplay
##   HudGroups.show_group("gameplay")   # shows gameplay, hides implant
##   HudGroups.toggle_group("implant")  # toggle between gameplay and implant

## Which groups are mutually exclusive — showing one hides the others.
## Modal and debug are independent (they overlay on top of anything).
const EXCLUSIVE_GROUPS: Array[String] = ["gameplay", "implant"]

var _groups: Dictionary = {}  # group_name -> Array[Control]
var _active_exclusive: String = "gameplay"


func register(node: Control, group: String) -> void:
	if not _groups.has(group):
		_groups[group] = []
	if node not in _groups[group]:
		_groups[group].append(node)
	# Apply current visibility state
	if group in EXCLUSIVE_GROUPS:
		node.visible = (group == _active_exclusive)


func unregister(node: Control, group: String) -> void:
	if _groups.has(group):
		_groups[group].erase(node)


## Show a group. If it's exclusive, hide the other exclusive groups.
func show_group(group: String) -> void:
	if group in EXCLUSIVE_GROUPS:
		_active_exclusive = group
		for g: String in EXCLUSIVE_GROUPS:
			_set_group_visible(g, g == group)
	else:
		_set_group_visible(group, true)


## Hide a group. If exclusive, falls back to "gameplay".
func hide_group(group: String) -> void:
	if group in EXCLUSIVE_GROUPS:
		show_group("gameplay")
	else:
		_set_group_visible(group, false)


## Toggle between gameplay and the specified group.
func toggle_group(group: String) -> void:
	if _active_exclusive == group:
		show_group("gameplay")
	else:
		show_group(group)


## Check if a group is currently active.
func is_group_active(group: String) -> bool:
	if group in EXCLUSIVE_GROUPS:
		return _active_exclusive == group
	# Non-exclusive: check if any member is visible
	if _groups.has(group):
		for node: Control in _groups[group]:
			if is_instance_valid(node) and node.visible:
				return true
	return false


func _set_group_visible(group: String, vis: bool) -> void:
	if not _groups.has(group):
		return
	for node: Control in _groups[group]:
		if is_instance_valid(node):
			node.visible = vis