import { BN } from 'ethereumjs-util';
import BNJs from 'bn.js';
import { EthUnit, EthereumActionContract } from '../models';
/** Converts functionSignature to hexadecimal string */
export declare function functionSignatureToHex(functionSignature: string): string;
/** Finds the method from abi json object array
 * Returns the methodName with inputSignature in a string format (myMethod(uint256,string))
 */
export declare function abiToFunctionSignature(methodName: string, abi: any[]): string;
/** Checks if nullOrEmpty and ethereum spesific hexadecimal and Buffer values that implies empty */
export declare function isNullOrEmptyEthereumValue(obj: any): boolean;
/** Uses web3-utils toWei conversion */
export declare function toWeiBN(amount: BNJs | number): BNJs;
/** convert a decimal string from fromType to Wei units
 *  Returns a string */
export declare function toWeiString(amount: string, fromType: EthUnit): string;
export declare function fromWeiString(wei: string, toType: EthUnit): string;
/** Converts a (string) value from one ETH unit to another - returns a string */
export declare function convertEthUnit(amount: string, fromType: EthUnit, toType: EthUnit): string;
/** Converts wei amount to Gwei
 *  1 Gwei = 1000000000 wei */
export declare function toGweiFromWei(amount: number | BN): number;
/** Generates hexadecimal string for transaction data from EthereumActionContract */
export declare function generateDataFromContractAction(contractAction: EthereumActionContract): import("../models").EthereumTxDataBrand;
/** if value is null or a empty Eth value (e.g. '0x00..') returns null, otherwise return the value passed-in */
export declare function nullifyIfEmptyEthereumValue(value: any): any;