import type { FloatingEvents } from "../types";

/**
 * Minimal typed pub/sub emitter used by `FloatingContext.events`.
 * Ported verbatim from the React source — no framework coupling, just a
 * topic-keyed `Map<string, Set<listener>>`.
 */
export function createEventEmitter(): FloatingEvents {
	// biome-ignore lint/suspicious/noExplicitAny: emitter payloads are type-erased.
	const map = new Map<string, Set<(data: any) => void>>();
	return {
		emit(event, data) {
			map.get(event)?.forEach((listener) => {
				listener(data);
			});
		},
		on(event, listener) {
			if (!map.has(event)) {
				map.set(event, new Set());
			}
			// biome-ignore lint/style/noNonNullAssertion: just set it above.
			map.get(event)!.add(listener);
		},
		off(event, listener) {
			map.get(event)?.delete(listener);
		},
	};
}