extends Node
## Central registry for all runtime-tunable parameters.
## Add a new param with one _reg_f() call in _register_all() — the menu picks it up automatically.
## Access: DP.f("key")  •  Persist: DP.save() / DP.load_saved()  •  Reset: DP.reset_all()

signal any_changed(key: String, value: Variant)

const SAVE_PATH := "user://debug_params.cfg"

var _params: Dictionary = {}


func _ready() -> void:
	_register_all()
	load_saved()


func _register_all() -> void:
	# ── Movement ──────────────────────────────────────────────────────────────
	_reg_f("Movement", "walk_speed",         6.0,   1.0,  40.0)
	_reg_f("Movement", "charge_speed",       18.0,  5.0,  60.0)
	_reg_f("Movement", "walk_accel",         14.0,  1.0,  80.0)
	_reg_f("Movement", "charge_accel",       40.0,  5.0, 120.0)
	_reg_f("Movement", "deceleration",       12.0,  1.0,  50.0)
	_reg_f("Movement", "charge_decel",        3.5,  0.5,  20.0)
	_reg_f("Movement", "jump_velocity",       4.5,  1.0,  20.0)
	# ── Turning ───────────────────────────────────────────────────────────────
	_reg_f("Turning",  "walk_turn_fast",      8.0,  0.5,  25.0)
	_reg_f("Turning",  "walk_turn_slow",      3.5,  0.5,  15.0)
	_reg_f("Turning",  "charge_turn",         0.55, 0.05,  3.0, 0.01)
	_reg_f("Turning",  "visual_turn_speed",  12.0,  1.0,  40.0)
	# ── Dust ──────────────────────────────────────────────────────────────────
	_reg_f("Dust",     "dust_lifetime",       0.9,  0.1,   4.0)
	_reg_f("Dust",     "dust_explosiveness",  0.35, 0.0,   1.0)
	_reg_f("Dust",     "dust_spread",        45.0,  5.0,  90.0)
	_reg_f("Dust",     "dust_gravity_y",     -1.5,-15.0,   0.0)
	_reg_f("Dust",     "walk_scale_min",      0.35, 0.05,  3.0)
	_reg_f("Dust",     "walk_scale_max",      0.65, 0.05,  3.0)
	_reg_f("Dust",     "walk_vel_min",        0.8,  0.1,  12.0)
	_reg_f("Dust",     "walk_vel_max",        1.8,  0.1,  12.0)
	_reg_f("Dust",     "charge_scale_min",    1.0,  0.05,  6.0)
	_reg_f("Dust",     "charge_scale_max",    2.2,  0.05,  6.0)
	_reg_f("Dust",     "charge_vel_min",      2.8,  0.1,  20.0)
	_reg_f("Dust",     "charge_vel_max",      5.5,  0.1,  20.0)


func _reg_f(section: String, key: String, default: float,
		min_val: float, max_val: float, step: float = 0.05) -> void:
	_params[key] = {
		"value":   default,
		"default": default,
		"section": section,
		"type":    TYPE_FLOAT,
		"min":     min_val,
		"max":     max_val,
		"step":    step,
	}


## Read a float param. Panics on unknown key — intentional: typos should be loud.
func f(key: String) -> float:
	return _params[key]["value"] as float


func set_value(key: String, value: Variant) -> void:
	if not _params.has(key):
		return
	_params[key]["value"] = value
	any_changed.emit(key, value)


## Returns the full metadata dict — used by DebugMenu to build UI.
func get_all() -> Dictionary:
	return _params


func save() -> void:
	var cfg := ConfigFile.new()
	for key: String in _params:
		var p: Dictionary = _params[key]
		cfg.set_value(p["section"], key, p["value"])
	cfg.save(SAVE_PATH)


func load_saved() -> void:
	var cfg := ConfigFile.new()
	if cfg.load(SAVE_PATH) != OK:
		return
	for section: String in cfg.get_sections():
		for key: String in cfg.get_section_keys(section):
			if _params.has(key):
				_params[key]["value"] = cfg.get_value(section, key)


func reset_all() -> void:
	for key: String in _params:
		_params[key]["value"] = _params[key]["default"]
	any_changed.emit("__all__", null)