import { formatUnits, parseUnits } from 'viem'

import { PERCENTAGE_SCALE } from '../constants'

export const roundToDecimals: (arg0: number, arg1: number) => number = (
  num,
  decimals,
) => {
  const multiplier = Math.pow(10, decimals)
  // Include Number.EPSILON to help with floating point precision (i.e. expected 1.325 but got 1.324999999999)
  return Math.round((num + Number.EPSILON) * multiplier) / multiplier
}

export const getBigIntFromPercent = (value: number): bigint => {
  return BigInt(getNumberFromPercent(value))
}

export const getNumberFromPercent = (value: number, scale?: bigint): number => {
  if (!scale) scale = PERCENTAGE_SCALE
  return Math.round(Number(scale) * value) / 100
}

const PERCENTAGE_SCALE_FACTOR = 10 ** 4 // 4 decimal places
export const fromBigIntToPercent = (
  value: bigint | number,
  scale?: bigint,
): number => {
  const numberVal = BigInt(value)
  if (!scale) {
    const rawPercentage = parseFloat(formatUnits(numberVal, 6)) * 100
    return (
      Math.round(rawPercentage * PERCENTAGE_SCALE_FACTOR) /
      PERCENTAGE_SCALE_FACTOR
    )
  }

  const percentage =
    (numberVal * BigInt(100) * BigInt(PERCENTAGE_SCALE_FACTOR)) / scale
  return Number(percentage) / PERCENTAGE_SCALE_FACTOR
}

export const getBigIntTokenValue = (
  value: number,
  decimals: number,
): bigint => {
  return parseUnits(value.toString(), decimals)
}

export const fromBigIntToTokenValue = (
  amount: bigint,
  decimals: number,
): string => {
  return formatUnits(amount, decimals)
}