import { VirtualAddress, VirtualAddressComponents } from "@relay-protocol/types"
import { ethers } from "ethers"

import { getCheckSummedAddress } from "./utils"

/**
 * Generates a virtual Ethereum address from token components
 * @param components The token components (family, chainId, address)
 * @returns A checksummed Ethereum address derived from the token ID
 * @remarks This function first generates a token ID using the components,
 * then converts the last 20 bytes of the hash to an Ethereum address.
 * This is equivalent to the Solidity: address(uint160(uint256(addressHash)))
 */

export function generateAddress(
  components: VirtualAddressComponents
): VirtualAddress {
  const { chainId, address, family } = components
  const addressHash = ethers.keccak256(
    ethers.solidityPacked(
      ["string", "uint256", family === "ethereum-vm" ? "address" : "string"],
      [family, chainId, getCheckSummedAddress(family, address)]
    )
  )
  const addressBytes = addressHash.slice(2).slice(-40)
  return ethers.getAddress("0x" + addressBytes) as `0x${string}`
}