/**
 * Statement Store (SSS) allowance preflight — pure storage read, no signing.
 *
 * The People chain stores SSS allowances under a deterministic key:
 *   b":statement_allowance:" ++ raw_32_byte_account_pubkey
 *
 * We can check this via a single `state_getStorage` RPC call — no transaction,
 * no phone dialog. Non-null, non-"0x" result means the allowance is present.
 *
 * The stored value is `(used_bytes: u32, max_bytes: u32)` (e.g. `(2, 512000)`)
 * — there is no expiry block in the value. Expiry is enforced chain-side by
 * *pruning* the key when the allowance lapses, so key-present ⇔ allowance valid
 * (and not expired). Verified empirically against paseo-next-v2 People.
 *
 * IMPORTANT — which account: the allowance belongs to the **statement-signing
 * account** (the session's `localAccount`), NOT the product account. The
 * product account signs on-chain extrinsics (DotNS records); it never writes
 * to the statement store and therefore never holds an SSS allowance (its key
 * is always null). The mobile-signing transport rides the statement store: the
 * terminal publishes Request statements signed by `localAccount`, so that is
 * the account the chain grants the allowance to at login. Use
 * `statementSigningAccount(userSession)` to pick it — checking the product
 * account is a false-negative that blocks every valid session.
 *
 * Reference: substrate/primitives/statement-store/src/lib.rs
 */
/**
 * The account whose SSS allowance gates statement publishing for a session:
 * the session's local (statement-signing) account. This is the account that
 * signs the Request statements relayed to the phone — the one the chain grants
 * `StatementStoreAllowance` to at login. Returns its raw 32-byte public key, or
 * `null` if the session shape lacks a usable local account.
 *
 * Typed structurally (just the field we read) rather than importing the
 * concrete `UserSession` type from `@parity/product-sdk-terminal`, keeping the
 * SDK out of the headless deploy/login hot paths.
 */
declare function statementSigningAccount(userSession: {
    localAccount?: {
        accountId?: Uint8Array;
    };
} | null | undefined): Uint8Array | null;
/**
 * Build the hex-encoded storage key for an SSS allowance check.
 *
 * Format: 0x + hex(":statement_allowance:" + pubkey_32_bytes)
 * No twox/blake2 hashing — the key is the raw concatenation.
 */
declare function sssStorageKey(pubkey: Uint8Array): string;
/**
 * Check whether a Statement Store allowance is present on the People chain.
 *
 * @returns
 *   - `true`  — allowance present (continue)
 *   - `false` — allowance absent / expired (user must re-login)
 *   - `null`  — could not determine (network error or timeout; caller decides whether to block)
 */
declare function checkSSSAllowance(pubkey: Uint8Array, peopleEndpoints: string[], timeoutMs?: number): Promise<boolean | null>;

export { checkSSSAllowance, sssStorageKey, statementSigningAccount };