import { parseState, serializeState } from './state.js';

export function createRefreshTracker(readSignature, refresh) {
  let previous = null;
  let timer = null;

  function check() {
    const next = String(readSignature() ?? '');
    if (next === previous) return false;
    previous = next;
    refresh();
    return true;
  }

  return {
    check,
    start(interval = 250) {
      if (timer !== null) return;
      check();
      timer = setInterval(check, interval);
    },
    stop() {
      if (timer === null) return;
      clearInterval(timer);
      timer = null;
    },
  };
}

export function createStateController(widget, node) {
  let state = parseState(widget?.value);

  function getState() {
    return state;
  }

  function setState(next) {
    state = next;
    return state;
  }

  function refresh() {
    state = parseState(widget?.value);
    return state;
  }

  function persist() {
    const oldValue = widget.value;
    const value = serializeState(state);
    widget.value = value;
    widget.callback?.(value);
    node?.onWidgetChanged?.(widget.name, value, oldValue, widget);
    node?.graph?.setDirtyCanvas?.(true, true);
    return value;
  }

  return { getState, setState, refresh, persist };
}