import { fromHexString, toHexString } from "@chainsafe/ssz";
import bls from "@chainsafe/bls/switchable";
import { createBeaconConfig } from "@lodestar/config";
import { mainnetConfig } from "./constants.js";
import { networksChainConfig } from "@lodestar/config/networks";
import fetch from "node-fetch";

export function concatUint8Array(data: Uint8Array[]) {
  const l = data.reduce((l, d) => l + d.length, 0);
  let result = new Uint8Array(l);
  let offset = 0;
  data.forEach((d) => {
    result.set(d, offset);
    offset += d.length;
  });
  return result;
}

export function getDefaultClientConfig() {
  const chainConfig = createBeaconConfig(
    networksChainConfig.mainnet,
    fromHexString(mainnetConfig.genesis_validator_root)
  );
  return {
    genesis: {
      committee: mainnetConfig.committee_pk,
      slot: parseInt(mainnetConfig.slot),
      time: parseInt(mainnetConfig.genesis_time),
    },
    chainConfig,
    n: 1,
  };
}

export async function handleGETRequest(
  url: string,
  retry: number = 3
): Promise<any> {
  if (retry < 0) {
    throw Error(`GET request failed: ${url}`);
  }
  try {
    const ret = await fetch(url);
    return await ret.json();
  } catch (e) {
    console.error(`failed GET request (${url}): ${e.message}`);
    return handleGETRequest(url, retry - 1);
  }
}