import { utils } from 'ethers'

/**
 * Truncates string (in the middle) via given lenght value
 */
export function truncate(value: string, length: number) {
  if (value.length <= length) {
    return value
  }

  const separator = '...'
  const stringLength = length - separator.length
  const frontLength = Math.ceil(stringLength / 2)
  const backLength = Math.floor(stringLength / 2)

  return value.substring(0, frontLength) + separator + value.substring(value.length - backLength)
}

/**
 * Converts hex to utf8 string if it is valid bytes
 */
export function convertHexToUtf8(value: string) {
  if (utils.isHexString(value)) {
    return utils.toUtf8String(value)
  }

  return value
}

/**
 * Gets message from various signing request methods by filtering out
 * a value that is not an address (thus is a message).
 * If it is a hex string, it gets converted to utf8 string
 */
export function getSignParamsMessage(params: string[]) {
  const message = params.filter(p => !utils.isAddress(p))[0]

  return convertHexToUtf8(message)
}

/**
 * Gets data from various signTypedData request methods by filtering out
 * a value that is not an address (thus is data).
 * If data is a string convert it to object
 */
export function getSignTypedDataParamsData(params: string[]) {
  const data = params.filter(p => !utils.isAddress(p))[0]

  if (typeof data === 'string') {
    return JSON.parse(data)
  }

  return data
}