const DEFAULT_PADDING = 64;
const EXTRA_SPACING = 12;

function getMenuPadding(extraSpacing) {
  if (typeof tt === "undefined" || typeof tt.getMenuButtonBoundingClientRect !== "function") {
    return 0;
  }
  try {
    const rect = tt.getMenuButtonBoundingClientRect();
    if (!rect) {
      return 0;
    }
    if (typeof rect.bottom === "number") {
      return rect.bottom + extraSpacing;
    }
    if (typeof rect.top === "number" && typeof rect.height === "number") {
      return rect.top + rect.height + extraSpacing;
    }
  } catch (error) {
    console.warn("safe-area: menu rect unavailable", error);
  }
  return 0;
}

function getStatusBarPadding(extraSpacing) {
  if (typeof tt === "undefined" || typeof tt.getSystemInfoSync !== "function") {
    return 0;
  }
  try {
    const info = tt.getSystemInfoSync();
    return (info && info.statusBarHeight ? info.statusBarHeight : 0) + extraSpacing;
  } catch (error) {
    console.warn("safe-area: system info unavailable", error);
  }
  return 0;
}

function getPageSafeTop(extraSpacing = EXTRA_SPACING, fallback = DEFAULT_PADDING) {
  const menuPadding = getMenuPadding(extraSpacing);
  if (menuPadding) {
    return Math.round(menuPadding);
  }
  const statusPadding = getStatusBarPadding(extraSpacing);
  if (statusPadding) {
    return Math.round(statusPadding);
  }
  return fallback;
}

module.exports = {
  getPageSafeTop
};