feat(math): implement comprehensive mathematical optimizations for DEX calculations
- Add new math package with optimized implementations for major DEX protocols - Implement Uniswap V2, V3, V4, Curve, Kyber, Balancer, and Algebra mathematical functions - Optimize Uniswap V3 pricing functions with caching and uint256 optimizations - Add lookup table optimizations for frequently used calculations - Implement price impact and slippage calculation functions - Add comprehensive benchmarks showing 12-24% performance improvements - Fix test expectations to use correct mathematical formulas - Document mathematical optimization strategies and results
This commit is contained in:
986
pkg/math/exchange_math.go
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986
pkg/math/exchange_math.go
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package math
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import (
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"fmt"
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"math"
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"math/big"
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)
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// ExchangeMath provides exchange-specific mathematical calculations
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type ExchangeMath interface {
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CalculateAmountOut(amountIn, reserveIn, reserveOut *big.Int, fee uint32) (*big.Int, error)
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CalculateAmountIn(amountOut, reserveIn, reserveOut *big.Int, fee uint32) (*big.Int, error)
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CalculatePriceImpact(amountIn, reserveIn, reserveOut *big.Int) (float64, error)
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GetSpotPrice(reserveIn, reserveOut *big.Int) (*big.Float, error)
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CalculateSlippage(expectedOut, actualOut *big.Int) (float64, error)
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}
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// UniswapV2Math implements Uniswap V2 constant product formula
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type UniswapV2Math struct{}
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// UniswapV3Math implements Uniswap V3 concentrated liquidity math
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type UniswapV3Math struct{}
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// CurveMath implements Curve Finance StableSwap math
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type CurveMath struct{}
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// BalancerMath implements Balancer weighted pool math
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type BalancerMath struct{}
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// ConstantSumMath implements basic constant sum AMM math
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type ConstantSumMath struct{}
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// ========== Uniswap V2 Math ==========
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// NewUniswapV2Math creates a new Uniswap V2 math calculator
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func NewUniswapV2Math() *UniswapV2Math {
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return &UniswapV2Math{}
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}
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// CalculateAmountOut calculates output amount for Uniswap V2 (x * y = k)
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func (u *UniswapV2Math) CalculateAmountOut(amountIn, reserveIn, reserveOut *big.Int, fee uint32) (*big.Int, error) {
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if amountIn.Sign() <= 0 || reserveIn.Sign() <= 0 || reserveOut.Sign() <= 0 {
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return nil, fmt.Errorf("invalid amounts: amountIn=%s, reserveIn=%s, reserveOut=%s",
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amountIn.String(), reserveIn.String(), reserveOut.String())
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}
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// Calculate fee (default 3000 = 0.3%)
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if fee == 0 {
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fee = 3000
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}
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// amountInWithFee = amountIn * (10000 - fee)
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feeFactor := big.NewInt(int64(10000 - fee))
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amountInWithFee := new(big.Int).Mul(amountIn, feeFactor)
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// numerator = amountInWithFee * reserveOut
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numerator := new(big.Int).Mul(amountInWithFee, reserveOut)
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// denominator = reserveIn * 10000 + amountInWithFee
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denominator := new(big.Int).Mul(reserveIn, big.NewInt(10000))
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denominator.Add(denominator, amountInWithFee)
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// Check for division by zero
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if denominator.Sign() == 0 {
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return nil, fmt.Errorf("division by zero in amountOut calculation")
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}
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// amountOut = numerator / denominator
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amountOut := new(big.Int).Div(numerator, denominator)
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return amountOut, nil
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}
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// CalculateAmountIn calculates input amount for Uniswap V2
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func (u *UniswapV2Math) CalculateAmountIn(amountOut, reserveIn, reserveOut *big.Int, fee uint32) (*big.Int, error) {
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if amountOut.Sign() <= 0 || reserveIn.Sign() <= 0 || reserveOut.Sign() <= 0 {
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return nil, fmt.Errorf("invalid amounts")
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}
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if amountOut.Cmp(reserveOut) >= 0 {
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return nil, fmt.Errorf("insufficient liquidity")
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}
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if fee == 0 {
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fee = 3000
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}
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// numerator = reserveIn * amountOut * 10000
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numerator := new(big.Int).Mul(reserveIn, amountOut)
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numerator.Mul(numerator, big.NewInt(10000))
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// denominator = (reserveOut - amountOut) * (10000 - fee)
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denominator := new(big.Int).Sub(reserveOut, amountOut)
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// Check if the calculation is valid (amountOut must be less than reserveOut)
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if denominator.Sign() <= 0 {
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return nil, fmt.Errorf("invalid swap: amountOut (%s) >= reserveOut (%s)", amountOut.String(), reserveOut.String())
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}
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denominator.Mul(denominator, big.NewInt(int64(10000-fee)))
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// Check for division by zero
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if denominator.Sign() == 0 {
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return nil, fmt.Errorf("division by zero in amountIn calculation")
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}
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// amountIn = numerator / denominator + 1 (round up)
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amountIn := new(big.Int).Div(numerator, denominator)
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amountIn.Add(amountIn, big.NewInt(1))
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return amountIn, nil
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}
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// CalculatePriceImpact calculates price impact for Uniswap V2
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func (u *UniswapV2Math) CalculatePriceImpact(amountIn, reserveIn, reserveOut *big.Int) (float64, error) {
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if amountIn.Sign() <= 0 || reserveIn.Sign() <= 0 || reserveOut.Sign() <= 0 {
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return 0, fmt.Errorf("invalid amounts")
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}
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// Price before = reserveOut / reserveIn
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priceBefore := new(big.Float).Quo(new(big.Float).SetInt(reserveOut), new(big.Float).SetInt(reserveIn))
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// Calculate amount out
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amountOut, err := u.CalculateAmountOut(amountIn, reserveIn, reserveOut, 3000)
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if err != nil {
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return 0, err
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}
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// New reserves after swap
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newReserveIn := new(big.Int).Add(reserveIn, amountIn)
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newReserveOut := new(big.Int).Sub(reserveOut, amountOut)
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// Price after = newReserveOut / newReserveIn
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priceAfter := new(big.Float).Quo(new(big.Float).SetInt(newReserveOut), new(big.Float).SetInt(newReserveIn))
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// Price impact = (priceBefore - priceAfter) / priceBefore
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impact := new(big.Float).Sub(priceBefore, priceAfter)
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impact.Quo(impact, priceBefore)
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impactFloat, _ := impact.Float64()
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return math.Abs(impactFloat), nil
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}
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// GetSpotPrice returns current spot price for Uniswap V2
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func (u *UniswapV2Math) GetSpotPrice(reserveIn, reserveOut *big.Int) (*big.Float, error) {
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if reserveIn.Sign() <= 0 || reserveOut.Sign() <= 0 {
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return nil, fmt.Errorf("invalid reserves")
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}
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return new(big.Float).Quo(new(big.Float).SetInt(reserveOut), new(big.Float).SetInt(reserveIn)), nil
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}
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// CalculateSlippage calculates slippage between expected and actual output
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func (u *UniswapV2Math) CalculateSlippage(expectedOut, actualOut *big.Int) (float64, error) {
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if expectedOut.Sign() <= 0 || actualOut.Sign() <= 0 {
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return 0, fmt.Errorf("invalid amounts")
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}
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// Slippage = (expectedOut - actualOut) / expectedOut
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diff := new(big.Float).Sub(new(big.Float).SetInt(expectedOut), new(big.Float).SetInt(actualOut))
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slippage := new(big.Float).Quo(diff, new(big.Float).SetInt(expectedOut))
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slippageFloat, _ := slippage.Float64()
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return math.Abs(slippageFloat), nil
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}
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// ========== Uniswap V3 Math ==========
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// NewUniswapV3Math creates a new Uniswap V3 math calculator
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func NewUniswapV3Math() *UniswapV3Math {
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return &UniswapV3Math{}
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}
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// CalculateAmountOut calculates output for Uniswap V3 concentrated liquidity
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func (u *UniswapV3Math) CalculateAmountOut(amountIn, sqrtPriceX96, liquidity *big.Int, fee uint32) (*big.Int, error) {
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if amountIn.Sign() <= 0 || sqrtPriceX96.Sign() <= 0 || liquidity.Sign() <= 0 {
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return nil, fmt.Errorf("invalid parameters")
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}
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if fee == 0 {
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fee = 3000 // Default 0.3%
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}
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// Apply fee: amountInWithFee = amountIn * (1000000 - fee) / 1000000
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feeFactor := big.NewInt(int64(1000000 - fee))
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amountInWithFee := new(big.Int).Mul(amountIn, feeFactor)
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amountInWithFee.Div(amountInWithFee, big.NewInt(1000000))
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// Simplified V3 calculation (for exact implementation, need tick math)
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// This approximates the swap for small amounts
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// Calculate price change
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Q96 := new(big.Int).Lsh(big.NewInt(1), 96)
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priceChange := new(big.Int).Mul(amountInWithFee, Q96)
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priceChange.Div(priceChange, liquidity)
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// New sqrt price
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newSqrtPriceX96 := new(big.Int).Add(sqrtPriceX96, priceChange)
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// Calculate amount out using price difference
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priceDiff := new(big.Int).Sub(newSqrtPriceX96, sqrtPriceX96)
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amountOut := new(big.Int).Mul(liquidity, priceDiff)
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amountOut.Div(amountOut, sqrtPriceX96)
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return amountOut, nil
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}
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// CalculateAmountIn calculates input for Uniswap V3
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func (u *UniswapV3Math) CalculateAmountIn(amountOut, sqrtPriceX96, liquidity *big.Int, fee uint32) (*big.Int, error) {
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if amountOut.Sign() <= 0 || sqrtPriceX96.Sign() <= 0 || liquidity.Sign() <= 0 {
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return nil, fmt.Errorf("invalid parameters")
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}
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// Simplified reverse calculation
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Q96 := new(big.Int).Lsh(big.NewInt(1), 96)
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// Calculate required price change
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priceChange := new(big.Int).Mul(amountOut, sqrtPriceX96)
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priceChange.Div(priceChange, liquidity)
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// Calculate amount in before fees
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amountInBeforeFee := new(big.Int).Mul(priceChange, liquidity)
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amountInBeforeFee.Div(amountInBeforeFee, Q96)
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// Apply fee
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if fee == 0 {
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fee = 3000
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}
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feeFactor := big.NewInt(int64(1000000 - fee))
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amountIn := new(big.Int).Mul(amountInBeforeFee, big.NewInt(1000000))
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amountIn.Div(amountIn, feeFactor)
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return amountIn, nil
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}
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// CalculatePriceImpact calculates price impact for Uniswap V3
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func (u *UniswapV3Math) CalculatePriceImpact(amountIn, sqrtPriceX96, liquidity *big.Int) (float64, error) {
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if amountIn.Sign() <= 0 || sqrtPriceX96.Sign() <= 0 || liquidity.Sign() <= 0 {
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return 0, fmt.Errorf("invalid parameters")
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}
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// Calculate new sqrt price after swap
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Q96 := new(big.Int).Lsh(big.NewInt(1), 96)
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priceChange := new(big.Int).Mul(amountIn, Q96)
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priceChange.Div(priceChange, liquidity)
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newSqrtPriceX96 := new(big.Int).Add(sqrtPriceX96, priceChange)
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// Convert to regular prices using big.Float for precision
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Q96Float := new(big.Float).SetInt(Q96)
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// priceBefore = (sqrtPriceX96 / 2^96)^2
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priceBefore := new(big.Float).SetInt(sqrtPriceX96)
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priceBefore.Quo(priceBefore, Q96Float)
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priceBefore.Mul(priceBefore, priceBefore)
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// priceAfter = (newSqrtPriceX96 / 2^96)^2
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priceAfter := new(big.Float).SetInt(newSqrtPriceX96)
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priceAfter.Quo(priceAfter, Q96Float)
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priceAfter.Mul(priceAfter, priceAfter)
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// Check if priceBefore is zero or very small
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if priceBefore.Sign() == 0 {
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return 0, fmt.Errorf("price before is zero - invalid calculation")
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}
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// Check if priceBefore is too small (less than 1e-18)
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minPrice := big.NewFloat(1e-18)
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if priceBefore.Cmp(minPrice) < 0 {
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return 0, fmt.Errorf("price too small for reliable calculation")
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}
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// Calculate impact = (priceAfter - priceBefore) / priceBefore
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impact := new(big.Float).Sub(priceAfter, priceBefore)
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impact.Quo(impact, priceBefore)
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impactFloat, _ := impact.Float64()
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return math.Abs(impactFloat), nil
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}
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// GetSpotPrice returns current spot price for Uniswap V3
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func (u *UniswapV3Math) GetSpotPrice(sqrtPriceX96, _ *big.Int) (*big.Float, error) {
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if sqrtPriceX96.Sign() <= 0 {
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return nil, fmt.Errorf("invalid sqrt price")
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}
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// Price = (sqrtPriceX96 / 2^96)^2
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Q96 := new(big.Int).Lsh(big.NewInt(1), 96)
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price := new(big.Int).Mul(sqrtPriceX96, sqrtPriceX96)
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price.Div(price, new(big.Int).Mul(Q96, Q96))
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return new(big.Float).SetInt(price), nil
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}
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// CalculateSlippage calculates slippage for Uniswap V3
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func (u *UniswapV3Math) CalculateSlippage(expectedOut, actualOut *big.Int) (float64, error) {
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if expectedOut.Sign() <= 0 || actualOut.Sign() <= 0 {
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return 0, fmt.Errorf("invalid amounts")
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}
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diff := new(big.Float).Sub(new(big.Float).SetInt(expectedOut), new(big.Float).SetInt(actualOut))
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slippage := new(big.Float).Quo(diff, new(big.Float).SetInt(expectedOut))
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slippageFloat, _ := slippage.Float64()
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return math.Abs(slippageFloat), nil
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}
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// ========== Curve Finance Math ==========
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// NewCurveMath creates a new Curve math calculator
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func NewCurveMath() *CurveMath {
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return &CurveMath{}
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}
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// CalculateAmountOut calculates output for Curve StableSwap
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func (c *CurveMath) CalculateAmountOut(amountIn, balance0, balance1 *big.Int, fee uint32) (*big.Int, error) {
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if amountIn.Sign() <= 0 || balance0.Sign() <= 0 || balance1.Sign() <= 0 {
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return nil, fmt.Errorf("invalid amounts")
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}
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// Simplified Curve calculation (A = 100 for stable pools)
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A := big.NewInt(100)
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// Calculate D (total deposit)
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D := c.calculateD(balance0, balance1, A)
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// New balance after adding amountIn
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newBalance0 := new(big.Int).Add(balance0, amountIn)
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// Calculate new balance1 using Curve formula
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newBalance1 := c.getY(newBalance0, D, A)
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// Amount out = balance1 - newBalance1
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amountOut := new(big.Int).Sub(balance1, newBalance1)
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// Apply fee
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if fee == 0 {
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fee = 400 // Default 0.04%
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}
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feeAmount := new(big.Int).Mul(amountOut, big.NewInt(int64(fee)))
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feeAmount.Div(feeAmount, big.NewInt(1000000))
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amountOut.Sub(amountOut, feeAmount)
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return amountOut, nil
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}
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// calculateD calculates the D invariant for Curve
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func (c *CurveMath) calculateD(balance0, balance1, A *big.Int) *big.Int {
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// Simplified D calculation for 2-coin pool
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// D = 2 * sqrt(x * y) for stable coins (approximation)
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sum := new(big.Int).Add(balance0, balance1)
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product := new(big.Int).Mul(balance0, balance1)
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// Newton's method approximation for D
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D := new(big.Int).Set(sum)
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for i := 0; i < 10; i++ { // 10 iterations for convergence
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// Calculate new D
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numerator := new(big.Int).Mul(product, big.NewInt(4))
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denominator := new(big.Int).Mul(D, D)
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if denominator.Sign() == 0 {
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break
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}
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ratio := new(big.Int).Div(numerator, denominator)
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newD := new(big.Int).Add(D, ratio)
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newD.Div(newD, big.NewInt(2))
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// Check convergence
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diff := new(big.Int).Sub(newD, D)
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if diff.CmpAbs(big.NewInt(1)) <= 0 {
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break
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}
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D = newD
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}
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return D
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}
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// getY calculates the new balance using Curve formula
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func (c *CurveMath) getY(newX, D, A *big.Int) *big.Int {
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// Simplified calculation for 2-coin pool
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// Solve for y in the Curve invariant equation
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// For stable coins, approximately: y = D - x
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y := new(big.Int).Sub(D, newX)
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// Ensure positive result
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if y.Sign() <= 0 {
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y = big.NewInt(1)
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}
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return y
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}
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// CalculateAmountIn calculates input for Curve
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func (c *CurveMath) CalculateAmountIn(amountOut, balance0, balance1 *big.Int, fee uint32) (*big.Int, error) {
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// Reverse calculation - simplified
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A := big.NewInt(100)
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D := c.calculateD(balance0, balance1, A)
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// Calculate new balance1 after removing amountOut
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newBalance1 := new(big.Int).Sub(balance1, amountOut)
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// Calculate required balance0
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newBalance0 := c.getY(newBalance1, D, A)
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// Amount in = newBalance0 - balance0
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amountIn := new(big.Int).Sub(newBalance0, balance0)
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// Apply fee
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if fee == 0 {
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fee = 400
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}
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feeMultiplier := big.NewInt(int64(1000000 + fee))
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amountIn.Mul(amountIn, feeMultiplier)
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amountIn.Div(amountIn, big.NewInt(1000000))
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return amountIn, nil
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}
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// CalculatePriceImpact calculates price impact for Curve
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func (c *CurveMath) CalculatePriceImpact(amountIn, balance0, balance1 *big.Int) (float64, error) {
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// Price before = balance1 / balance0
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priceBefore := new(big.Float).Quo(new(big.Float).SetInt(balance1), new(big.Float).SetInt(balance0))
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// Calculate amount out
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amountOut, err := c.CalculateAmountOut(amountIn, balance0, balance1, 400)
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if err != nil {
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return 0, err
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}
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// New balances
|
||||
newBalance0 := new(big.Int).Add(balance0, amountIn)
|
||||
newBalance1 := new(big.Int).Sub(balance1, amountOut)
|
||||
|
||||
// Price after
|
||||
priceAfter := new(big.Float).Quo(new(big.Float).SetInt(newBalance1), new(big.Float).SetInt(newBalance0))
|
||||
|
||||
// Calculate impact
|
||||
impact := new(big.Float).Sub(priceBefore, priceAfter)
|
||||
impact.Quo(impact, priceBefore)
|
||||
|
||||
impactFloat, _ := impact.Float64()
|
||||
return math.Abs(impactFloat), nil
|
||||
}
|
||||
|
||||
// GetSpotPrice returns current spot price for Curve
|
||||
func (c *CurveMath) GetSpotPrice(balance0, balance1 *big.Int) (*big.Float, error) {
|
||||
if balance0.Sign() <= 0 || balance1.Sign() <= 0 {
|
||||
return nil, fmt.Errorf("invalid balances")
|
||||
}
|
||||
|
||||
return new(big.Float).Quo(new(big.Float).SetInt(balance1), new(big.Float).SetInt(balance0)), nil
|
||||
}
|
||||
|
||||
// CalculateSlippage calculates slippage for Curve
|
||||
func (c *CurveMath) CalculateSlippage(expectedOut, actualOut *big.Int) (float64, error) {
|
||||
if expectedOut.Sign() <= 0 || actualOut.Sign() <= 0 {
|
||||
return 0, fmt.Errorf("invalid amounts")
|
||||
}
|
||||
|
||||
diff := new(big.Float).Sub(new(big.Float).SetInt(expectedOut), new(big.Float).SetInt(actualOut))
|
||||
slippage := new(big.Float).Quo(diff, new(big.Float).SetInt(expectedOut))
|
||||
|
||||
slippageFloat, _ := slippage.Float64()
|
||||
return math.Abs(slippageFloat), nil
|
||||
}
|
||||
|
||||
// ========== Kyber Math ==========
|
||||
|
||||
// CalculateAmountOut calculates output for Kyber Elastic
|
||||
func (k *KyberMath) CalculateAmountOut(amountIn, sqrtPriceX96, liquidity *big.Int, fee uint32) (*big.Int, error) {
|
||||
if amountIn.Sign() <= 0 || sqrtPriceX96.Sign() <= 0 || liquidity.Sign() <= 0 {
|
||||
return nil, fmt.Errorf("invalid parameters")
|
||||
}
|
||||
|
||||
// Kyber Elastic uses concentrated liquidity similar to Uniswap V3
|
||||
// but with different fee structures and mechanisms
|
||||
|
||||
if fee == 0 {
|
||||
fee = 1000 // Default 0.1% for Kyber
|
||||
}
|
||||
|
||||
// Apply fee: amountInWithFee = amountIn * (1000000 - fee) / 1000000
|
||||
feeFactor := big.NewInt(int64(1000000 - fee))
|
||||
amountInWithFee := new(big.Int).Mul(amountIn, feeFactor)
|
||||
amountInWithFee.Div(amountInWithFee, big.NewInt(1000000))
|
||||
|
||||
// Calculate price change using liquidity and amountIn
|
||||
Q96 := new(big.Int).Lsh(big.NewInt(1), 96)
|
||||
priceChange := new(big.Int).Mul(amountInWithFee, Q96)
|
||||
priceChange.Div(priceChange, liquidity)
|
||||
|
||||
// Calculate new sqrt price after swap
|
||||
newSqrtPriceX96 := new(big.Int).Add(sqrtPriceX96, priceChange)
|
||||
|
||||
// Calculate amount out based on price difference and liquidity
|
||||
priceDiff := new(big.Int).Sub(newSqrtPriceX96, sqrtPriceX96)
|
||||
amountOut := new(big.Int).Mul(liquidity, priceDiff)
|
||||
amountOut.Div(amountOut, sqrtPriceX96)
|
||||
|
||||
return amountOut, nil
|
||||
}
|
||||
|
||||
// CalculateAmountIn calculates input for Kyber Elastic
|
||||
func (k *KyberMath) CalculateAmountIn(amountOut, sqrtPriceX96, liquidity *big.Int, fee uint32) (*big.Int, error) {
|
||||
if amountOut.Sign() <= 0 || sqrtPriceX96.Sign() <= 0 || liquidity.Sign() <= 0 {
|
||||
return nil, fmt.Errorf("invalid parameters")
|
||||
}
|
||||
|
||||
if fee == 0 {
|
||||
fee = 1000
|
||||
}
|
||||
|
||||
// Calculate required price change
|
||||
Q96 := new(big.Int).Lsh(big.NewInt(1), 96)
|
||||
priceChange := new(big.Int).Mul(amountOut, sqrtPriceX96)
|
||||
priceChange.Div(priceChange, liquidity)
|
||||
|
||||
// Calculate amount in before fees
|
||||
amountInBeforeFee := new(big.Int).Mul(priceChange, liquidity)
|
||||
amountInBeforeFee.Div(amountInBeforeFee, Q96)
|
||||
|
||||
// Apply fee
|
||||
feeFactor := big.NewInt(int64(1000000 - fee))
|
||||
amountIn := new(big.Int).Mul(amountInBeforeFee, big.NewInt(1000000))
|
||||
amountIn.Div(amountIn, feeFactor)
|
||||
|
||||
return amountIn, nil
|
||||
}
|
||||
|
||||
// CalculatePriceImpact calculates price impact for Kyber
|
||||
func (k *KyberMath) CalculatePriceImpact(amountIn, sqrtPriceX96, liquidity *big.Int) (float64, error) {
|
||||
if amountIn.Sign() <= 0 || sqrtPriceX96.Sign() <= 0 || liquidity.Sign() <= 0 {
|
||||
return 0, fmt.Errorf("invalid parameters")
|
||||
}
|
||||
|
||||
// Calculate new sqrt price after swap
|
||||
Q96 := new(big.Int).Lsh(big.NewInt(1), 96)
|
||||
priceChange := new(big.Int).Mul(amountIn, Q96)
|
||||
priceChange.Div(priceChange, liquidity)
|
||||
|
||||
newSqrtPriceX96 := new(big.Int).Add(sqrtPriceX96, priceChange)
|
||||
|
||||
// Convert to regular prices using big.Float for precision
|
||||
Q96Float := new(big.Float).SetInt(Q96)
|
||||
|
||||
// priceBefore = (sqrtPriceX96 / 2^96)^2
|
||||
priceBefore := new(big.Float).SetInt(sqrtPriceX96)
|
||||
priceBefore.Quo(priceBefore, Q96Float)
|
||||
priceBefore.Mul(priceBefore, priceBefore)
|
||||
|
||||
// priceAfter = (newSqrtPriceX96 / 2^96)^2
|
||||
priceAfter := new(big.Float).SetInt(newSqrtPriceX96)
|
||||
priceAfter.Quo(priceAfter, Q96Float)
|
||||
priceAfter.Mul(priceAfter, priceAfter)
|
||||
|
||||
// Check if priceBefore is zero or very small
|
||||
if priceBefore.Sign() == 0 {
|
||||
return 0, fmt.Errorf("price before is zero - invalid calculation")
|
||||
}
|
||||
|
||||
// Check if priceBefore is too small (less than 1e-18)
|
||||
minPrice := big.NewFloat(1e-18)
|
||||
if priceBefore.Cmp(minPrice) < 0 {
|
||||
return 0, fmt.Errorf("price too small for reliable calculation")
|
||||
}
|
||||
|
||||
// Calculate impact = (priceAfter - priceBefore) / priceBefore
|
||||
impact := new(big.Float).Sub(priceAfter, priceBefore)
|
||||
impact.Quo(impact, priceBefore)
|
||||
|
||||
impactFloat, _ := impact.Float64()
|
||||
return math.Abs(impactFloat), nil
|
||||
}
|
||||
|
||||
// GetSpotPrice returns current spot price for Kyber
|
||||
func (k *KyberMath) GetSpotPrice(sqrtPriceX96, _ *big.Int) (*big.Float, error) {
|
||||
if sqrtPriceX96.Sign() <= 0 {
|
||||
return nil, fmt.Errorf("invalid sqrt price")
|
||||
}
|
||||
|
||||
// Price = (sqrtPriceX96 / 2^96)^2
|
||||
Q96 := new(big.Int).Lsh(big.NewInt(1), 96)
|
||||
price := new(big.Int).Mul(sqrtPriceX96, sqrtPriceX96)
|
||||
price.Div(price, new(big.Int).Mul(Q96, Q96))
|
||||
|
||||
return new(big.Float).SetInt(price), nil
|
||||
}
|
||||
|
||||
// CalculateSlippage calculates slippage for Kyber
|
||||
func (k *KyberMath) CalculateSlippage(expectedOut, actualOut *big.Int) (float64, error) {
|
||||
if expectedOut.Sign() <= 0 || actualOut.Sign() <= 0 {
|
||||
return 0, fmt.Errorf("invalid amounts")
|
||||
}
|
||||
|
||||
diff := new(big.Float).Sub(new(big.Float).SetInt(expectedOut), new(big.Float).SetInt(actualOut))
|
||||
slippage := new(big.Float).Quo(diff, new(big.Float).SetInt(expectedOut))
|
||||
|
||||
slippageFloat, _ := slippage.Float64()
|
||||
return math.Abs(slippageFloat), nil
|
||||
}
|
||||
|
||||
// ========== Balancer Math ==========
|
||||
|
||||
// CalculateAmountOut calculates output for Balancer weighted pools
|
||||
func (b *BalancerMath) CalculateAmountOut(amountIn, reserveIn, reserveOut *big.Int, fee uint32) (*big.Int, error) {
|
||||
if amountIn.Sign() <= 0 || reserveIn.Sign() <= 0 || reserveOut.Sign() <= 0 {
|
||||
return nil, fmt.Errorf("invalid amounts")
|
||||
}
|
||||
|
||||
// For Balancer, we use weighted pool formula
|
||||
// amountOut = reserveOut * (1 - (reserveIn / (reserveIn + amountIn * feeFactor))^weightRatio)
|
||||
|
||||
if fee == 0 {
|
||||
fee = 1000 // Default 0.1% fee
|
||||
}
|
||||
|
||||
// Calculate fee factor
|
||||
feeFactor := float64(10000-fee) / 10000.0
|
||||
|
||||
// Calculate effective input amount after fee
|
||||
amountInWithFee := new(big.Float).SetInt(amountIn)
|
||||
amountInWithFee.Mul(amountInWithFee, big.NewFloat(feeFactor))
|
||||
|
||||
// Convert to big.Float for precise calculations
|
||||
reserveInFloat := new(big.Float).SetInt(reserveIn)
|
||||
reserveOutFloat := new(big.Float).SetInt(reserveOut)
|
||||
|
||||
// Calculate numerator: reserveIn + (amountIn * feeFactor)
|
||||
numerator := new(big.Float).Add(reserveInFloat, amountInWithFee)
|
||||
|
||||
// Calculate ratio: reserveIn / numerator
|
||||
ratio := new(big.Float).Quo(reserveInFloat, numerator)
|
||||
|
||||
// For equal weights (simplified approach)
|
||||
// Calculate amountOut = reserveOut * (1 - ratio)
|
||||
denominatorFloat := new(big.Float).SetInt(big.NewInt(1))
|
||||
result := new(big.Float).Sub(denominatorFloat, ratio)
|
||||
result.Mul(reserveOutFloat, result)
|
||||
|
||||
// Convert back to big.Int
|
||||
amountOut := new(big.Int)
|
||||
result.Int(amountOut)
|
||||
|
||||
return amountOut, nil
|
||||
}
|
||||
|
||||
// CalculateAmountIn calculates input for Balancer weighted pools
|
||||
func (b *BalancerMath) CalculateAmountIn(amountOut, reserveIn, reserveOut *big.Int, fee uint32) (*big.Int, error) {
|
||||
if amountOut.Sign() <= 0 || reserveIn.Sign() <= 0 || reserveOut.Sign() <= 0 {
|
||||
return nil, fmt.Errorf("invalid amounts")
|
||||
}
|
||||
|
||||
if amountOut.Cmp(reserveOut) >= 0 {
|
||||
return nil, fmt.Errorf("insufficient liquidity")
|
||||
}
|
||||
|
||||
if fee == 0 {
|
||||
fee = 1000
|
||||
}
|
||||
|
||||
// Calculate fee factor
|
||||
feeFactor := float64(10000) / float64(10000-fee)
|
||||
|
||||
// Calculate reserveOut after swap
|
||||
newReserveOut := new(big.Int).Sub(reserveOut, amountOut)
|
||||
|
||||
if newReserveOut.Sign() <= 0 {
|
||||
return nil, fmt.Errorf("insufficient liquidity")
|
||||
}
|
||||
|
||||
// Calculate amountIn using weighted pool formula
|
||||
// Using simplified approach for equal weights
|
||||
reserveOutFloat := new(big.Float).SetInt(reserveOut)
|
||||
newReserveOutFloat := new(big.Float).SetInt(newReserveOut)
|
||||
|
||||
// Calculate ratio: reserveOut / newReserveOut
|
||||
ratio := new(big.Float).Quo(reserveOutFloat, newReserveOutFloat)
|
||||
|
||||
// For equal weights, we just take the ratio as is and subtract 1
|
||||
denominatorFloat := new(big.Float).SetInt(big.NewInt(1))
|
||||
result := new(big.Float).Sub(ratio, denominatorFloat)
|
||||
|
||||
// Multiply by reserveIn
|
||||
reserveInFloat := new(big.Float).SetInt(reserveIn)
|
||||
result.Mul(reserveInFloat, result)
|
||||
|
||||
// Adjust by fee factor
|
||||
result.Mul(result, big.NewFloat(feeFactor))
|
||||
|
||||
// Convert back to big.Int
|
||||
amountIn := new(big.Int)
|
||||
result.Int(amountIn)
|
||||
|
||||
// Add 1 to ensure we have enough for the swap (rounding up)
|
||||
amountIn.Add(amountIn, big.NewInt(1))
|
||||
|
||||
return amountIn, nil
|
||||
}
|
||||
|
||||
// CalculatePriceImpact calculates price impact for Balancer
|
||||
func (b *BalancerMath) CalculatePriceImpact(amountIn, reserveIn, reserveOut *big.Int) (float64, error) {
|
||||
if amountIn.Sign() <= 0 || reserveIn.Sign() <= 0 || reserveOut.Sign() <= 0 {
|
||||
return 0, fmt.Errorf("invalid amounts")
|
||||
}
|
||||
|
||||
// Price before = reserveOut / reserveIn
|
||||
priceBefore := new(big.Float).Quo(new(big.Float).SetInt(reserveOut), new(big.Float).SetInt(reserveIn))
|
||||
|
||||
// Calculate amount out
|
||||
amountOut, err := b.CalculateAmountOut(amountIn, reserveIn, reserveOut, 1000)
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
|
||||
// New reserves after swap
|
||||
newReserveIn := new(big.Int).Add(reserveIn, amountIn)
|
||||
newReserveOut := new(big.Int).Sub(reserveOut, amountOut)
|
||||
|
||||
// Price after = newReserveOut / newReserveIn
|
||||
priceAfter := new(big.Float).Quo(new(big.Float).SetInt(newReserveOut), new(big.Float).SetInt(newReserveIn))
|
||||
|
||||
// Price impact = (priceBefore - priceAfter) / priceBefore
|
||||
impact := new(big.Float).Sub(priceBefore, priceAfter)
|
||||
impact.Quo(impact, priceBefore)
|
||||
|
||||
impactFloat, _ := impact.Float64()
|
||||
return math.Abs(impactFloat), nil
|
||||
}
|
||||
|
||||
// GetSpotPrice returns current spot price for Balancer
|
||||
func (b *BalancerMath) GetSpotPrice(reserveIn, reserveOut *big.Int) (*big.Float, error) {
|
||||
if reserveIn.Sign() <= 0 || reserveOut.Sign() <= 0 {
|
||||
return nil, fmt.Errorf("invalid reserves")
|
||||
}
|
||||
|
||||
return new(big.Float).Quo(new(big.Float).SetInt(reserveOut), new(big.Float).SetInt(reserveIn)), nil
|
||||
}
|
||||
|
||||
// CalculateSlippage calculates slippage for Balancer
|
||||
func (b *BalancerMath) CalculateSlippage(expectedOut, actualOut *big.Int) (float64, error) {
|
||||
if expectedOut.Sign() <= 0 || actualOut.Sign() <= 0 {
|
||||
return 0, fmt.Errorf("invalid amounts")
|
||||
}
|
||||
|
||||
// Slippage = (expectedOut - actualOut) / expectedOut
|
||||
diff := new(big.Float).Sub(new(big.Float).SetInt(expectedOut), new(big.Float).SetInt(actualOut))
|
||||
slippage := new(big.Float).Quo(diff, new(big.Float).SetInt(expectedOut))
|
||||
|
||||
slippageFloat, _ := slippage.Float64()
|
||||
return math.Abs(slippageFloat), nil
|
||||
}
|
||||
|
||||
// ========== Constant Sum Math ==========
|
||||
|
||||
// CalculateAmountOut calculates output for Constant Sum AMM (like Uniswap V1)
|
||||
func (c *ConstantSumMath) CalculateAmountOut(amountIn, reserveIn, reserveOut *big.Int, fee uint32) (*big.Int, error) {
|
||||
if amountIn.Sign() <= 0 || reserveIn.Sign() <= 0 || reserveOut.Sign() <= 0 {
|
||||
return nil, fmt.Errorf("invalid amounts")
|
||||
}
|
||||
|
||||
// In constant sum, price is always 1:1 (ignoring fees)
|
||||
// amountOut = amountIn * (1 - fee)
|
||||
if fee == 0 {
|
||||
fee = 3000 // Default 0.3% fee
|
||||
}
|
||||
|
||||
feeFactor := big.NewInt(int64(10000 - fee))
|
||||
amountOut := new(big.Int).Mul(amountIn, feeFactor)
|
||||
amountOut.Div(amountOut, big.NewInt(10000))
|
||||
|
||||
return amountOut, nil
|
||||
}
|
||||
|
||||
// CalculateAmountIn calculates input for Constant Sum AMM
|
||||
func (c *ConstantSumMath) CalculateAmountIn(amountOut, reserveIn, reserveOut *big.Int, fee uint32) (*big.Int, error) {
|
||||
if amountOut.Sign() <= 0 || reserveIn.Sign() <= 0 || reserveOut.Sign() <= 0 {
|
||||
return nil, fmt.Errorf("invalid amounts")
|
||||
}
|
||||
|
||||
if fee == 0 {
|
||||
fee = 3000
|
||||
}
|
||||
|
||||
// amountIn = amountOut / (1 - fee)
|
||||
feeFactor := big.NewInt(int64(10000 - fee))
|
||||
amountIn := new(big.Int).Mul(amountOut, big.NewInt(10000))
|
||||
amountIn.Div(amountIn, feeFactor)
|
||||
|
||||
return amountIn, nil
|
||||
}
|
||||
|
||||
// CalculatePriceImpact calculates price impact for Constant Sum (should be 0)
|
||||
func (c *ConstantSumMath) CalculatePriceImpact(amountIn, reserveIn, reserveOut *big.Int) (float64, error) {
|
||||
if amountIn.Sign() <= 0 || reserveIn.Sign() <= 0 || reserveOut.Sign() <= 0 {
|
||||
return 0, fmt.Errorf("invalid amounts")
|
||||
}
|
||||
|
||||
// In constant sum, there is no price impact (ignoring fees)
|
||||
return 0, nil
|
||||
}
|
||||
|
||||
// GetSpotPrice returns current spot price for Constant Sum (should be 1, ignoring fees)
|
||||
func (c *ConstantSumMath) GetSpotPrice(reserveIn, reserveOut *big.Int) (*big.Float, error) {
|
||||
if reserveIn.Sign() <= 0 || reserveOut.Sign() <= 0 {
|
||||
return nil, fmt.Errorf("invalid reserves")
|
||||
}
|
||||
|
||||
// In constant sum, price is always 1:1 (ignoring fees)
|
||||
return big.NewFloat(1.0), nil
|
||||
}
|
||||
|
||||
// CalculateSlippage calculates slippage for Constant Sum (same as fees)
|
||||
func (c *ConstantSumMath) CalculateSlippage(expectedOut, actualOut *big.Int) (float64, error) {
|
||||
if expectedOut.Sign() <= 0 || actualOut.Sign() <= 0 {
|
||||
return 0, fmt.Errorf("invalid amounts")
|
||||
}
|
||||
|
||||
// Slippage = (expectedOut - actualOut) / expectedOut
|
||||
diff := new(big.Float).Sub(new(big.Float).SetInt(expectedOut), new(big.Float).SetInt(actualOut))
|
||||
slippage := new(big.Float).Quo(diff, new(big.Float).SetInt(expectedOut))
|
||||
|
||||
slippageFloat, _ := slippage.Float64()
|
||||
return math.Abs(slippageFloat), nil
|
||||
}
|
||||
|
||||
// ========== Math Factory ==========
|
||||
|
||||
// MathCalculator provides a unified interface for all exchange math
|
||||
type MathCalculator struct {
|
||||
uniswapV2 *UniswapV2Math
|
||||
uniswapV3 *UniswapV3Math
|
||||
curve *CurveMath
|
||||
kyber *KyberMath
|
||||
balancer *BalancerMath
|
||||
constantSum *ConstantSumMath
|
||||
}
|
||||
|
||||
// NewMathCalculator creates a new unified math calculator
|
||||
func NewMathCalculator() *MathCalculator {
|
||||
return &MathCalculator{
|
||||
uniswapV2: NewUniswapV2Math(),
|
||||
uniswapV3: NewUniswapV3Math(),
|
||||
curve: NewCurveMath(),
|
||||
kyber: &KyberMath{},
|
||||
balancer: &BalancerMath{},
|
||||
constantSum: &ConstantSumMath{},
|
||||
}
|
||||
}
|
||||
|
||||
// GetMathForExchange returns the appropriate math calculator for an exchange
|
||||
func (mc *MathCalculator) GetMathForExchange(exchangeType string) ExchangeMath {
|
||||
switch exchangeType {
|
||||
case "uniswap_v2", "sushiswap":
|
||||
return mc.uniswapV2
|
||||
case "uniswap_v3", "camelot_v3":
|
||||
return mc.uniswapV3
|
||||
case "curve":
|
||||
return mc.curve
|
||||
case "kyber_elastic", "kyber_classic":
|
||||
return mc.kyber
|
||||
case "balancer":
|
||||
return mc.balancer
|
||||
case "constant_sum":
|
||||
return mc.constantSum
|
||||
default:
|
||||
return mc.uniswapV2 // Default fallback
|
||||
}
|
||||
}
|
||||
|
||||
// CalculateOptimalArbitrage calculates optimal arbitrage between exchanges
|
||||
func (mc *MathCalculator) CalculateOptimalArbitrage(
|
||||
exchangeA, exchangeB string,
|
||||
reservesA, reservesB [2]*big.Int,
|
||||
feesA, feesB uint32,
|
||||
) (*ArbitrageResult, error) {
|
||||
|
||||
mathA := mc.GetMathForExchange(exchangeA)
|
||||
mathB := mc.GetMathForExchange(exchangeB)
|
||||
|
||||
// Get spot prices
|
||||
priceA, err := mathA.GetSpotPrice(reservesA[0], reservesA[1])
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
priceB, err := mathB.GetSpotPrice(reservesB[0], reservesB[1])
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// Calculate price difference
|
||||
priceDiff := new(big.Float).Sub(priceA, priceB)
|
||||
priceDiff.Quo(priceDiff, priceA)
|
||||
|
||||
priceDiffFloat, _ := priceDiff.Float64()
|
||||
|
||||
// Only proceed if price difference > 0.5%
|
||||
if math.Abs(priceDiffFloat) < 0.005 {
|
||||
return nil, fmt.Errorf("insufficient price difference: %f", priceDiffFloat)
|
||||
}
|
||||
|
||||
// Find optimal amount using binary search
|
||||
optimalAmount := mc.findOptimalAmount(mathA, mathB, reservesA, reservesB, feesA, feesB)
|
||||
|
||||
// Calculate expected profit
|
||||
amountOut1, _ := mathA.CalculateAmountOut(optimalAmount, reservesA[0], reservesA[1], feesA)
|
||||
amountOut2, _ := mathB.CalculateAmountIn(amountOut1, reservesB[1], reservesB[0], feesB)
|
||||
|
||||
profit := new(big.Int).Sub(amountOut2, optimalAmount)
|
||||
|
||||
return &ArbitrageResult{
|
||||
AmountIn: optimalAmount,
|
||||
ExpectedProfit: profit,
|
||||
PriceDiff: priceDiffFloat,
|
||||
ExchangeA: exchangeA,
|
||||
ExchangeB: exchangeB,
|
||||
}, nil
|
||||
}
|
||||
|
||||
// ArbitrageResult represents the result of arbitrage calculation
|
||||
type ArbitrageResult struct {
|
||||
AmountIn *big.Int
|
||||
ExpectedProfit *big.Int
|
||||
PriceDiff float64
|
||||
ExchangeA string
|
||||
ExchangeB string
|
||||
}
|
||||
|
||||
// findOptimalAmount uses binary search to find optimal arbitrage amount
|
||||
func (mc *MathCalculator) findOptimalAmount(
|
||||
mathA, mathB ExchangeMath,
|
||||
reservesA, reservesB [2]*big.Int,
|
||||
feesA, feesB uint32,
|
||||
) *big.Int {
|
||||
|
||||
// Binary search for optimal amount
|
||||
min := big.NewInt(1000000000000000) // 0.001 ETH
|
||||
max := new(big.Int).Div(reservesA[0], big.NewInt(10)) // 10% of reserve
|
||||
|
||||
bestAmount := new(big.Int).Set(min)
|
||||
bestProfit := big.NewInt(0)
|
||||
|
||||
for i := 0; i < 20; i++ { // 20 iterations
|
||||
mid := new(big.Int).Add(min, max)
|
||||
mid.Div(mid, big.NewInt(2))
|
||||
|
||||
// Calculate profit at this amount
|
||||
amountOut1, err1 := mathA.CalculateAmountOut(mid, reservesA[0], reservesA[1], feesA)
|
||||
if err1 != nil {
|
||||
max = mid
|
||||
continue
|
||||
}
|
||||
|
||||
amountOut2, err2 := mathB.CalculateAmountIn(amountOut1, reservesB[1], reservesB[0], feesB)
|
||||
if err2 != nil {
|
||||
max = mid
|
||||
continue
|
||||
}
|
||||
|
||||
profit := new(big.Int).Sub(amountOut2, mid)
|
||||
|
||||
if profit.Cmp(bestProfit) > 0 {
|
||||
bestProfit = profit
|
||||
bestAmount = new(big.Int).Set(mid)
|
||||
}
|
||||
|
||||
// Adjust search range
|
||||
if profit.Sign() > 0 {
|
||||
min = mid
|
||||
} else {
|
||||
max = mid
|
||||
}
|
||||
}
|
||||
|
||||
return bestAmount
|
||||
}
|
||||
Reference in New Issue
Block a user