/**
 * Chain-safe JSON normalization for `account_update` operations.
 *
 * Protocol types (steem/libraries/protocol):
 * - `authority` — weight_threshold (uint32), account_auths / key_auths (fc::flat_map)
 * - `account_update_operation` — account, optional owner/active/posting, memo_key, json_metadata (string)
 *
 * JSON-RPC (`condenser_api.broadcast_transaction` → fc::from_variant):
 * - `authority` is a variant_object, not a bare key_auths array.
 * - `fc::flat_map` serializes as an array of [key, weight] pairs (see fc/container/flat.hpp),
 *   not a JSON object `{ "key": weight }` — object maps cause bad_cast_exception.
 * - `json_metadata` must be a string (protocol `string`), not a parsed JSON object.
 *
 * Binary signing (transaction digest) uses the same logical fields; the serializer packs
 * flat_maps as sorted on-wire maps (see serializeAuthority in serializer/transaction.ts).
 */
/** One entry in an fc::flat_map after JSON (de)serialization: [key, weight]. */
export type AuthorityWeightPair = [string, number];
/**
 * `steem::protocol::authority` as returned by condenser / required for broadcast JSON.
 * account_auths: flat_map<account_name_type, uint16>
 * key_auths: flat_map<public_key_type, uint16> (keys are "STM..." strings in JSON)
 */
export type ChainAuthority = {
    weight_threshold: number;
    /** FC flat_map JSON: `[["account", weight], ...]` */
    account_auths: AuthorityWeightPair[];
    /** FC flat_map JSON: `[["STM...", weight], ...]` */
    key_auths: AuthorityWeightPair[];
};
/**
 * `steem::protocol::account_update_operation` payload for JSON broadcast and signing.
 * Operation tuple form: `["account_update", AccountUpdatePayload]`.
 */
export type AccountUpdatePayload = {
    account: string;
    owner: ChainAuthority;
    active: ChainAuthority;
    posting: ChainAuthority;
    memo_key: string;
    json_metadata: string;
};
export type OperationTuple = [string, Record<string, unknown>];
/**
 * Coerce `json_metadata` to protocol `string` (FC string field).
 * Node rejects object/array variants with bad_cast when broadcasting.
 */
export declare function normalizeChainJsonMetadata(value: unknown): string;
/** Normalize API authority data (get_accounts-style input; accepts pair arrays or object maps). */
export declare function normalizeAuthoritySource(source: unknown): ChainAuthority;
/**
 * Coerce account_update operation payload to protocol JSON shape for signing and broadcast.
 * Emits fc::flat_map fields as pair arrays, not object maps.
 */
export declare function sanitizeAccountUpdatePayload(payload: Record<string, unknown>): AccountUpdatePayload;
/**
 * Normalize an operation tuple before signing or JSON broadcast.
 * Only account_update is rewritten; other operations pass through unchanged.
 */
export declare function normalizeOperationForBroadcast(operation: unknown): unknown;
/** Normalize transaction operations/extensions for JSON broadcast after signing. */
export declare function normalizeTransactionForBroadcast(trx: Record<string, unknown>): Record<string, unknown>;
/**
 * Authority value for binary serialization (fail-fast on array mistaken for object).
 * Mirrors steem wallet_api::update_account which assigns authority structs, not key_auths arrays.
 */
export declare function resolveAuthorityForSerialize(auth: unknown, field: string): Record<string, unknown>;