package scanner

import (
	"math/big"

	"github.com/ethereum/go-ethereum/common"
)

// TokenDecimalMap provides decimal information for common tokens
var TokenDecimalMap = map[common.Address]int{
	common.HexToAddress("0x82aF49447D8a07e3bd95BD0d56f35241523fBab1"): 18, // WETH
	common.HexToAddress("0xFF970A61A04b1cA14834A43f5dE4533eBDDB5CC8"): 6,  // USDC
	common.HexToAddress("0xFd086bC7CD5C481DCC9C85ebE478A1C0b69FCbb9"): 6,  // USDT
	common.HexToAddress("0x2f2a2543B76A4166549F7aaB2e75Bef0aefC5B0f"): 8,  // WBTC
	common.HexToAddress("0x912CE59144191C1204E64559FE8253a0e49E6548"): 18, // ARB
}

// GetTokenDecimals returns decimals for a token (defaults to 18)
func GetTokenDecimals(token common.Address) int {
	if decimals, ok := TokenDecimalMap[token]; ok {
		return decimals
	}
	return 18
}

// NormalizeToEther converts token amount to ether equivalent considering decimals
func NormalizeToEther(amount *big.Int, token common.Address) *big.Float {
	if amount == nil {
		return big.NewFloat(0)
	}

	decimals := GetTokenDecimals(token)
	divisor := new(big.Int).Exp(big.NewInt(10), big.NewInt(int64(decimals)), nil)

	result := new(big.Float).Quo(
		new(big.Float).SetInt(amount),
		new(big.Float).SetInt(divisor),
	)

	return result
}