/**
 * DOM references and shared application state.
 * Element refs are resolved lazily via getters so modules can be imported before DOM is ready.
 */

/** @returns {HTMLDivElement|null} */
export function getCalendarEl() {
  return document.getElementById("calendar");
}

/** @returns {HTMLElement|null} */
export function getMonthTitleEl() {
  return document.getElementById("monthTitle");
}

/** @returns {HTMLDivElement|null} */
export function getDutyListEl() {
  return document.getElementById("dutyList");
}

/** @returns {HTMLElement|null} */
export function getLoadingEl() {
  return document.getElementById("loading");
}

/** @returns {HTMLElement|null} */
export function getErrorEl() {
  return document.getElementById("error");
}

/** @returns {HTMLElement|null} */
export function getAccessDeniedEl() {
  return document.getElementById("accessDenied");
}

/** @returns {HTMLElement|null} */
export function getHeaderEl() {
  return document.querySelector(".header");
}

/** @returns {HTMLElement|null} */
export function getWeekdaysEl() {
  return document.querySelector(".weekdays");
}

/** @returns {HTMLButtonElement|null} */
export function getPrevBtn() {
  return document.getElementById("prevMonth");
}

/** @returns {HTMLButtonElement|null} */
export function getNextBtn() {
  return document.getElementById("nextMonth");
}

/** @returns {HTMLDivElement|null} */
export function getCurrentDutyViewEl() {
  return document.getElementById("currentDutyView");
}

/** Currently viewed month (mutable). */
export const state = {
  /** @type {Date} */
  current: new Date(),
  /** @type {object[]} */
  lastDutiesForList: [],
  /** @type {ReturnType<typeof setInterval>|null} */
  todayRefreshInterval: null,
  /** @type {'ru'|'en'} */
  lang: "ru",
  /** One-time bind flag for sticky scroll shadow listener. */
  stickyScrollBound: false,
  /** One-time bind flag for calendar (info button) hint document listeners. */
  calendarHintBound: false,
  /** One-time bind flag for duty marker hint document listeners. */
  dutyMarkerHintBound: false,
  /** Whether initData retry after ACCESS_DENIED has been attempted. */
  initDataRetried: false
};