/**
 * Revert decoding — turn the bytes a failed call came back with into the name
 * the contract actually reverted with.
 *
 * `isUnpredictableGas` says only THAT the call would revert. That was enough
 * while the answer was always the same one: a `transferFrom` failing on a
 * balance that cannot cover the deposit. It is not enough any more, because
 * `requestDepositWithKyc` reverts for a whole family of reasons the ABI
 * declares and the lender can do nothing about — the pool is stopped, the pool
 * is mid-clearing, their KYC lapsed, they are not on the allow list, the
 * allow-list signature's block window closed. Every one of those was reported
 * as "insufficient balance", so a fully funded lender was told to top up a
 * wallet that was never short.
 *
 * The revert data carries the answer. This module extracts it from whatever
 * envelope the provider wrapped it in and matches the 4-byte selector against
 * the custom errors the protocol declares.
 *
 * Pure, like everything else in `domain/`: bytes in, a name out. It never
 * decides what a lender is shown — `DepositFlow` maps the name to a code and
 * the application maps the code to its own words.
 */
/**
 * Which family a recognised revert belongs to, because the two are acted on
 * differently.
 *
 * `erc20` is the case `insufficient-balance` was named for and still means:
 * the token transfer itself failed, so the lender genuinely has to fund or
 * re-approve. `protocol` is everything else the protocol declares — a
 * condition of the pool or the lender's standing, which topping up cannot fix.
 */
export type RevertFamily = 'protocol' | 'erc20';
export interface DecodedRevert {
    /** The custom error's name, exactly as the ABI declares it. */
    name: string;
    family: RevertFamily;
    /** The reason of a `require(..., "…")` revert, when it was one. */
    reason?: string;
}
/**
 * Find the revert data on an error, wherever the provider left it.
 *
 * ethers v5 raises `UNPREDICTABLE_GAS_LIMIT` with the provider's own error
 * attached, and each provider nests the bytes one layer differently:
 * `error.data`, `error.error.data`, `error.data.originalError.data`, or only
 * inside the JSON `body` of a `SERVER_ERROR`. Rather than enumerate the
 * products, walk a fixed set of keys to a fixed depth and take the first value
 * that is shaped like revert data.
 */
export declare function extractRevertData(err: unknown): string | null;
/**
 * Decode a failed call's revert into the error the contract named, or `null`
 * when there is nothing recognisable to name.
 *
 * `null` is the honest answer for an unknown selector, an unrelated `require`
 * string, or an error with no revert data at all — the caller keeps whatever
 * it did before rather than inventing a diagnosis from bytes it cannot read.
 */
export declare function decodeRevert(err: unknown): DecodedRevert | null;