/**
 * change price with customer decimals to bigNum with 18 decimals
 * @param {number} price
 * @param {number} decimals
 * @return {string}
 */
export function parsePrice(price: number, decimals: number) {
  const n = 19 - decimals
  return price + new Array(n).join('0')
}

/**
 * format price with customer decimals to string for display
 * @param {number | string} price
 * @param {number} decimals
 * @param {number} fixed
 * @return {number | string}
 */
export function formatPrice(price: number|string, decimals?: number, fixed = 2) {
  if (!decimals) {
    return price
  }
  let str = price + ''
  const length = str.length
  str = str.padStart(decimals, '0')
  if (decimals >= length) {
    str = '0.' + str
  } else {
    const pos = length - decimals
    str = str.slice(0, pos) + '.' + str.slice(pos)
  }
  str = str.slice(0, str.lastIndexOf('.') + fixed + 1)
  return str
  // return str.replace(/0+$/, '').replace(/\.+$/, '')
}

/**
 * number to hex string
 * @param {number} chainId
 * @return {string}
 */
export function toHexChainId(chainId: number) {
  return '0x' + chainId.toString(16)
}