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

import (
	"math"
	"math/big"
)

// SqrtPriceX96ToPriceAdvanced converts sqrtPriceX96 to a price using advanced caching.
func SqrtPriceX96ToPriceAdvanced(sqrtPriceX96 *big.Int) *big.Float {
	// Initialize global cached constants
	initConstants()

	// price = (sqrtPriceX96 / 2^96)^2
	// price = sqrtPriceX96^2 / 2^192

	// Validate input
	if sqrtPriceX96 == nil || sqrtPriceX96.Sign() <= 0 {
		return new(big.Float).SetFloat64(0.0)
	}

	// Convert to big.Float for precision
	sqrtPrice := new(big.Float).SetInt(sqrtPriceX96)

	// Calculate sqrtPrice^2
	price := new(big.Float).Mul(sqrtPrice, sqrtPrice)

	// Divide by 2^192 using cached constant
	price.Quo(price, GetQ192Float())

	// Validate result is reasonable (not extremely high or low)
	priceFloat, _ := price.Float64()
	if math.IsNaN(priceFloat) || math.IsInf(priceFloat, 0) ||
		priceFloat > 1e20 || priceFloat < 1e-20 { // Extremely high/low prices are likely errors
		return new(big.Float).SetFloat64(1.0) // Default to 1.0 as safe fallback
	}

	return price
}

// PriceToSqrtPriceX96Advanced converts a price to sqrtPriceX96 using advanced caching.
func PriceToSqrtPriceX96Advanced(price *big.Float) *big.Int {
	// Initialize global cached constants
	initConstants()

	// sqrtPriceX96 = sqrt(price) * 2^96

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

	// Multiply by 2^96 using cached constant
	sqrtPrice.Mul(sqrtPrice, GetQ96Float())

	// Validate result
	resultFloat, _ := sqrtPrice.Float64()
	if math.IsNaN(resultFloat) || math.IsInf(resultFloat, 0) {
		return new(big.Int).SetUint64(0) // Return 0 for invalid results
	}

	// Convert to big.Int
	sqrtPriceX96 := new(big.Int)
	sqrtPrice.Int(sqrtPriceX96)

	return sqrtPriceX96
}

// TickToSqrtPriceX96Advanced converts a tick to sqrtPriceX96 using advanced caching.
func TickToSqrtPriceX96Advanced(tick int) *big.Int {
	// Initialize global cached constants
	initConstants()

	// sqrtPriceX96 = 1.0001^(tick/2) * 2^96
	// Using logarithms: 1.0001^(tick/2) = e^(ln(1.0001) * tick/2)
	logResult := GetLnBase() * float64(tick) / 2.0
	result := math.Exp(logResult)

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

	// Multiply by 2^96 using cached constant
	price.Mul(price, GetQ96Float())

	// Validate result
	resultFloat, _ := price.Float64()
	if math.IsNaN(resultFloat) || math.IsInf(resultFloat, 0) {
		return new(big.Int).SetUint64(0) // Return 0 for invalid results
	}

	// Convert to big.Int
	sqrtPriceX96 := new(big.Int)
	price.Int(sqrtPriceX96)

	return sqrtPriceX96
}

// SqrtPriceX96ToTickAdvanced converts sqrtPriceX96 to a tick using advanced caching.
func SqrtPriceX96ToTickAdvanced(sqrtPriceX96 *big.Int) int {
	// Initialize global cached constants
	initConstants()

	// tick = log_1.0001(sqrtPriceX96 / 2^96)^2
	// tick = 2 * ln(sqrtPriceX96 / 2^96) / ln(1.0001)

	if sqrtPriceX96.Cmp(big.NewInt(0)) <= 0 {
		return 0 // Invalid input
	}

	// Convert to big.Float
	sqrtPrice := new(big.Float).SetInt(sqrtPriceX96)
	q96Float := GetQ96Float()

	// Calculate ln(sqrtPriceX96 / 2^96) to avoid potential overflow
	ratio := new(big.Float).Quo(sqrtPrice, q96Float)
	lnRatio, _ := ratio.Float64()

	if lnRatio <= 0 {
		return 0 // Invalid ratio
	}

	lnValue := math.Log(lnRatio)

	// Calculate tick: tick = 2 * lnValue / ln(1.0001)
	tick := int(2.0 * lnValue * GetInvLnBase())

	return tick
}