import { BigNumberJson } from "@connext/types";
import { BigNumber, BigNumberish } from "ethers";

export const isBN = BigNumber.isBigNumber;

export const isBNJson = (value: any): boolean => !isBN(value) && !!value._hex;

export const toBN = (n: BigNumberish | BigNumberJson): BigNumber =>
  BigNumber.from(
    (n && typeof (n as BigNumberJson)._hex === "string")
      ? (n as BigNumberJson)._hex
      : typeof n.toString === "function"
        ? n.toString()
        : "0",
  );

export const toBNJson = (n: BigNumberish | BigNumberJson): BigNumberJson => ({
  _hex: toBN(n).toHexString(),
  _isBigNumber: true,
});

export const getBigNumberError = (value: any): string | undefined =>
  isBN(value) ? undefined : `Value "${value}" is not a BigNumber`;

export const getBigNumberishError = (value: any): string | undefined => {
  try {
    toBN(value);
  } catch (e) {
    return `Value "${value}" is not BigNumberish: ${e.message}`;
  }
  return undefined;
};