Typescript zod safeBigInt type

import { z } from "zod";

const maxBigInt = 9223372036854775807n;

// safeBigInt returns a validated zod bigint type.
export function safeBigInt() {
  return z
    .string()
    .max(19)
    .regex(/^\d+$/)
    .transform((value, ctx) => {
      // By now we have a string containing a positive integer.
      try {
        const v = BigInt(value);
        // Check the range here instead of .pipe(z.bigint().max(maxBigInt)).
        // Otherwise ts-rest would attempt to marshal the bigint to JSON (in an error response) which fails.
        if (v > maxBigInt) {
          throw new Error("too big");
        }
        return v;
        // eslint-disable-next-line @typescript-eslint/no-unused-vars
      } catch (err) {
        ctx.addIssue({
          code: "invalid_type",
          expected: typeof 0n,
          received: typeof value,
          message: "Invalid BigInt value",
        });

        return 0n;
      }
    });
}