@alcorexchange/alcor-swap-sdk/build/utils/maxLiquidityForAmounts.js

​​ **npm** ``` npm i @alcorexchange/alcor-swap-sdk ``` **yarn** ``` yarn add @alcorexchange/alcor-swap-sdk ``` ## Usage ### Import:

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.maxLiquidityForAmounts = maxLiquidityForAmounts;
var _internalConstants = require("../internalConstants");
/**
 * Returns an imprecise maximum amount of liquidity received for a given amount of token 0.
 * This function is available to accommodate LiquidityAmounts#getLiquidityForAmountA in the v3 periphery,
 * which could be more precise by at least 32 bits by dividing by Q64 instead of Q64 in the intermediate step,
 * and shifting the subtracted ratio left by 32 bits. This imprecise calculation will likely be replaced in a future
 * v3 router contract.
 * @param sqrtRatioLX64 The price at the lower boundary
 * @param sqrtRatioUX64 The price at the upper boundary
 * @param amountA The token0 amount
 * @returns liquidity for amountA, imprecise
 */
function maxLiquidityForAmountAImprecise(sqrtRatioLX64, sqrtRatioUX64, amountA) {
  if (sqrtRatioLX64 > sqrtRatioUX64) {
    [sqrtRatioLX64, sqrtRatioUX64] = [sqrtRatioUX64, sqrtRatioLX64];
  }
  const intermediate = sqrtRatioLX64 * sqrtRatioUX64 / _internalConstants.Q64;
  return BigInt(amountA) * intermediate / (sqrtRatioUX64 - sqrtRatioLX64);
}

/**
 * Returns a precise maximum amount of liquidity received for a given amount of token 0 by dividing by Q64 instead of Q64 in the intermediate step,
 * and shifting the subtracted ratio left by 32 bits.
 * @param sqrtRatioLX64 The price at the lower boundary
 * @param sqrtRatioUX64 The price at the upper boundary
 * @param amountA The token0 amount
 * @returns liquidity for amountA, precise
 */
function maxLiquidityForAmountAPrecise(sqrtRatioLX64, sqrtRatioUX64, amountA) {
  if (sqrtRatioLX64 > sqrtRatioUX64) {
    [sqrtRatioLX64, sqrtRatioUX64] = [sqrtRatioUX64, sqrtRatioLX64];
  }
  const numerator = BigInt(amountA) * sqrtRatioLX64 * sqrtRatioUX64;
  const denominator = _internalConstants.Q64 * (sqrtRatioUX64 - sqrtRatioLX64);
  return numerator / denominator;
}

/**
 * Computes the maximum amount of liquidity received for a given amount of token1
 * @param sqrtRatioLX64 The price at the lower tick boundary
 * @param sqrtRatioUX64 The price at the upper tick boundary
 * @param amountB The token1 amount
 * @returns liquidity for amountB
 */
function maxLiquidityForAmountB(sqrtRatioLX64, sqrtRatioUX64, amountB) {
  if (sqrtRatioLX64 > sqrtRatioUX64) {
    [sqrtRatioLX64, sqrtRatioUX64] = [sqrtRatioUX64, sqrtRatioLX64];
  }
  return BigInt(amountB) * _internalConstants.Q64 / (sqrtRatioUX64 - sqrtRatioLX64);
}

/**
 * Computes the maximum amount of liquidity received for a given amount of token0, token1,
 * and the prices at the tick boundaries.
 * @param sqrtRatioCurrentX64 the current price
 * @param sqrtRatioLX64 price at lower boundary
 * @param sqrtRatioUX64 price at upper boundary
 * @param amountA token0 amount
 * @param amountB token1 amount
 * @param useFullPrecision if false, liquidity will be maximized according to what the router can calculate,
 * not what core can theoretically support
 */
function maxLiquidityForAmounts(sqrtRatioCurrentX64, sqrtRatioLX64, sqrtRatioUX64, amountA, amountB, useFullPrecision) {
  if (sqrtRatioLX64 > sqrtRatioUX64) {
    [sqrtRatioLX64, sqrtRatioUX64] = [sqrtRatioUX64, sqrtRatioLX64];
  }
  const maxLiquidityForAmountA = useFullPrecision ? maxLiquidityForAmountAPrecise : maxLiquidityForAmountAImprecise;
  if (sqrtRatioCurrentX64 <= sqrtRatioLX64) {
    return maxLiquidityForAmountA(sqrtRatioLX64, sqrtRatioUX64, amountA);
  } else if (sqrtRatioCurrentX64 < sqrtRatioUX64) {
    const liquidityA = maxLiquidityForAmountA(sqrtRatioCurrentX64, sqrtRatioUX64, amountA);
    const liquidityB = maxLiquidityForAmountB(sqrtRatioLX64, sqrtRatioCurrentX64, amountB);
    return liquidityA < liquidityB ? liquidityA : liquidityB;
  } else {
    return maxLiquidityForAmountB(sqrtRatioLX64, sqrtRatioUX64, amountB);
  }
}