class_name MoveValidator
extends RefCounted
## Pure §6 validation: an emitted move is legal iff its canonical key is in the
## turn's available_moves (which NpcContent already computed from live state).
## No state reads here — membership is the whole test. Invalid moves are not an
## error; they are dropped and returned separately so the caller can log them.

const ID_MOVES := ["reveal", "offer_quest", "give_item", "accept_item"]
const BARE_MOVES := ["adjust_disposition", "refuse", "end_conversation", "become_hostile"]


static func _key(move: Dictionary) -> String:
	var name: String = move.get("name", "")
	var args: Array = move.get("args", [])
	if name in ID_MOVES:
		return "%s(%s)" % [name, str(args[0])] if not args.is_empty() else name
	return name  # bare/value moves key on the name alone


static func validate(moves: Array, available_moves: Array) -> Dictionary:
	var valid: Array = []
	var dropped: Array = []
	for move in moves:
		var name: String = move.get("name", "")
		if (name in ID_MOVES or name in BARE_MOVES) and _key(move) in available_moves:
			valid.append(move)
		else:
			dropped.append(move)
	return {"valid": valid, "dropped": dropped}