import { type Address } from "@morpho-org/blue-sdk";
import type { ERC20ApprovalAction, Transaction } from "../../../types/index.js";
/** Parameters for {@link encodeErc20Approval}. */
interface EncodeErc20ApprovalParams {
    token: Address;
    spender: Address;
    amount: bigint;
    chainId: number;
}
/**
 * Encodes a deep-frozen ERC-20 approval transaction for a supported SDK spender.
 *
 * Caps `amount` at the per-chain, per-token maximum from `MAX_TOKEN_APPROVALS` (defaults to
 * `maxUint256`). Used by {@link getRequirementsApproval} and {@link getGeneralAdapterRequirementsPermit2}.
 *
 * @param params - Encoding parameters.
 * @param params.token - ERC-20 token address to approve.
 * @param params.spender - Address granted the allowance. Must be GeneralAdapter1, Permit2,
 *   Midnight, MidnightBundles, or VaultExitBundlesV1 for the chain.
 * @param params.amount - Allowance amount before per-token cap.
 * @param params.chainId - The chain the transaction targets (used to resolve supported spenders and the per-token cap).
 * @returns A deep-frozen `Transaction<ERC20ApprovalAction>` with the capped approval amount.
 * @throws {UnsupportedErc20ApprovalSpenderError} when `spender` is not a supported SDK spender for `chainId`.
 * @example
 * ```ts
 * import { encodeErc20Approval } from "@morpho-org/morpho-sdk";
 *
 * const tx = encodeErc20Approval({
 *   token: USDC,
 *   spender: generalAdapter1,
 *   amount: 1_000_000n,
 *   chainId: 1,
 * });
 * // tx satisfies Readonly<Transaction<ERC20ApprovalAction>>
 * ```
 */
export declare const encodeErc20Approval: (params: EncodeErc20ApprovalParams) => Transaction<ERC20ApprovalAction>;
export {};