// Package uniswap provides mathematical functions for Uniswap V3 calculations.
package uniswap

import (
	"math"
	"math/big"

	"github.com/holiman/uint256"
)

// SqrtPriceX96ToPriceOptimized converts sqrtPriceX96 to a price using uint256 operations
// This is a more optimized version that avoids big.Float operations where possible
func SqrtPriceX96ToPriceOptimized(sqrtPriceX96 *uint256.Int) *big.Float {
	// price = (sqrtPriceX96 / 2^96)^2
	// price = sqrtPriceX96^2 / 2^192

	// Calculate sqrtPriceX96^2 using uint256
	sqrtPriceSquared := new(uint256.Int).Mul(sqrtPriceX96, sqrtPriceX96)

	// Convert to big.Float for division
	price := new(big.Float).SetInt(sqrtPriceSquared.ToBig())

	// Divide by 2^192 (which is (2^96)^2)
	// We can use a precomputed value for 2^192
	q192 := new(big.Float).SetInt(new(big.Int).Exp(big.NewInt(2), big.NewInt(192), nil))
	price.Quo(price, q192)

	return price
}

// PriceToSqrtPriceX96Optimized converts a price to sqrtPriceX96 using optimized operations
func PriceToSqrtPriceX96Optimized(price *big.Float) *uint256.Int {
	// sqrtPriceX96 = sqrt(price) * 2^96

	// Calculate sqrt(price)
	sqrtPrice := new(big.Float).Sqrt(price)

	// Multiply by 2^96
	q96Int := new(big.Int)
	q96Int.SetString(Q96, 10)
	q96 := new(big.Float).SetInt(q96Int)
	sqrtPrice.Mul(sqrtPrice, q96)

	// Convert to uint256
	sqrtPriceX96Int := sqrtPriceX96Big(sqrtPrice)
	sqrtPriceX96 := uint256.MustFromBig(sqrtPriceX96Int)

	return sqrtPriceX96
}

// Helper function to convert big.Float to big.Int
func sqrtPriceX96Big(f *big.Float) *big.Int {
	i, _ := f.Int(nil)
	return i
}

// TickToSqrtPriceX96Optimized converts a tick to sqrtPriceX96 using optimized operations
func TickToSqrtPriceX96Optimized(tick int) *uint256.Int {
	// sqrtPriceX96 = 1.0001^(tick/2) * 2^96
	// Using logarithms: 1.0001^(tick/2) = e^(ln(1.0001) * tick/2)
	lnBase := math.Log(1.0001) // ln(1.0001) ≈ 9.999500016666e-05
	logResult := lnBase * float64(tick) / 2.0
	result := math.Exp(logResult)

	// Convert to big.Float
	price := new(big.Float).SetFloat64(result)

	// Multiply by 2^96
	q96Int := new(big.Int)
	q96Int.SetString(Q96, 10)
	q96 := new(big.Float).SetInt(q96Int)
	price.Mul(price, q96)

	// Convert to uint256
	sqrtPriceX96Int := sqrtPriceX96Big(price)
	sqrtPriceX96 := uint256.MustFromBig(sqrtPriceX96Int)

	return sqrtPriceX96
}