refactor: update charm sync api

packages/charm-sync/src/utils.luau

@@ -0,0 +1,52 @@
+local Charm = require("../Charm")
+
+type Atom<T> = Charm.Atom<T>
+
+type NestedState = {
+	[string]: NestedState | () -> any,
+}
+
+type FlattenedState = {
+	[string]: () -> any,
+}
+
+local function isAtomOrSignal(value: any): boolean
+	return type(value) ~= "table" or (type(value.get) == "function" and type(value.set) == "function")
+end
+
+--- Flattens a nested map of atoms or signals into a single object with
+--- slash-separated keys. Useful for recursively collecting atoms returned by
+--- modules.
+---
+--- @param states A nested table of atoms or signals.
+--- @return A flattened map of atoms or signals.
+local function flattenState(states: NestedState): FlattenedState
+	local result: FlattenedState = {}
+
+	local function visit(node: NestedState, path: string)
+		for key, value in node do
+			local location = if path == "" then key else path .. "/" .. key
+
+			if isAtomOrSignal(value) then
+				result[location] = value :: () -> any
+			else
+				visit(value :: NestedState, location)
+			end
+		end
+	end
+
+	visit(states, "")
+
+	return result
+end
+
+local function signalToAtom<T>(getter: () -> T, setter: (value: ((T) -> T) | T) -> T): Atom<T>
+	return function(...)
+		return if select("#", ...) == 0 then getter() else setter((...))
+	end
+end
+
+return {
+	flattenState = flattenState,
+	signalToAtom = signalToAtom,
+}