// The backend can still report `pending_info` for a short moment after a match
// request is accepted. Without a grace window the user is bounced from
// /finding-match straight back to /questions-list.
//
// This lives in sessionStorage on purpose: it must not survive a WebView
// restart the way the old `match_submitted` localStorage flag did, because a
// sticky flag shadows the real profile status forever.

const STORAGE_KEY = "marriage:match-start-at";
const LEGACY_STORAGE_KEY = "match_submitted";
const GRACE_MS = 60_000;

export function markMatchStarted() {
  if (typeof window === "undefined") {
    return;
  }

  try {
    window.sessionStorage.setItem(STORAGE_KEY, String(Date.now()));
  } catch {
    // Storage can throw in private mode or when the quota is exhausted.
  }
}

export function isWithinMatchStartGrace() {
  if (typeof window === "undefined") {
    return false;
  }

  try {
    const rawValue = window.sessionStorage.getItem(STORAGE_KEY);

    if (!rawValue) {
      return false;
    }

    const startedAt = Number(rawValue);

    if (!Number.isFinite(startedAt) || Date.now() - startedAt > GRACE_MS) {
      window.sessionStorage.removeItem(STORAGE_KEY);
      return false;
    }

    return true;
  } catch {
    return false;
  }
}

export function clearMatchStartGrace() {
  if (typeof window === "undefined") {
    return;
  }

  try {
    window.sessionStorage.removeItem(STORAGE_KEY);
  } catch {
    // Ignore storage failures – the grace window expires on its own anyway.
  }
}

// Older builds wrote a `match_submitted` flag to localStorage and never removed
// it, which pinned affected users to /finding-match permanently. Drop it on boot
// so devices already carrying the flag recover without a manual data clear.
export function clearLegacyMatchSubmittedFlag() {
  if (typeof window === "undefined") {
    return;
  }

  try {
    window.localStorage.removeItem(LEGACY_STORAGE_KEY);
  } catch {
    // Ignore storage failures.
  }
}