calc tick and min order

components/modals/CreateOpenbookMarketModal.tsx

@@ -3,6 +3,8 @@ import { ModalProps } from '../../types/modal'
 import Modal from '../shared/Modal'
 import { OPENBOOK_PROGRAM_ID } from '@blockworks-foundation/mango-v4'
 import useMangoGroup from 'hooks/useMangoGroup'
+import { useMemo } from 'react'
+import { calculateTradingParameters } from 'utils/governance/listingTools'
 
 type CreateOpenbookMarketModalProps = {
   quoteSymbol: string
@@ -17,18 +19,36 @@ const CreateOpenbookMarketModal = ({
 }: ModalProps & CreateOpenbookMarketModalProps) => {
   const { group } = useMangoGroup()
 
-  const baseMint = group?.banksMapByName.get(baseSymbol)?.length
-    ? group.banksMapByName.get(baseSymbol)![0].mint.toBase58()
-    : ''
-  const quoteMint = group?.banksMapByName.get(quoteSymbol)?.length
-    ? group.banksMapByName.get(quoteSymbol)![0].mint.toBase58()
-    : ''
+  const baseBank = group?.banksMapByName.get(baseSymbol)?.length
+    ? group.banksMapByName.get(baseSymbol)![0]
+    : null
+  const quoteBank = group?.banksMapByName.get(quoteSymbol)?.length
+    ? group.banksMapByName.get(quoteSymbol)![0]
+    : null
+
+  const tradingParams = useMemo(() => {
+    if (baseBank && quoteBank) {
+      return calculateTradingParameters(
+        baseBank.uiPrice,
+        quoteBank.uiPrice,
+        baseBank.mintDecimals,
+        quoteBank.mintDecimals
+      )
+    }
+    return {
+      minOrder: 0,
+      priceTick: 0,
+      baseLotSize: 0,
+    }
+  }, [baseBank, quoteBank])
 
   return (
     <Modal isOpen={isOpen} onClose={onClose}>
       <p>OpenBook Program id: {OPENBOOK_PROGRAM_ID[CLUSTER].toBase58()}</p>
-      <p>Base mint: {baseMint}</p>
-      <p>Quote mint: {quoteMint}</p>
+      <p>Base mint: {baseBank?.mint.toBase58()}</p>
+      <p>Quote mint: {quoteBank?.mint.toBase58()}</p>
+      <p>Minimum order size: {tradingParams.minOrder} </p>
+      <p>Minimum price tick size: {tradingParams.priceTick} </p>
     </Modal>
   )
 }

utils/governance/listingTools.ts

@@ -167,7 +167,7 @@ export const getBestMarket = async ({
     ])
 
     const bestMarket = marketsData.sort((a, b) => b.volume24h - a.volume24h)
-
+    console.log(bestMarket)
     return new PublicKey(bestMarket[0].id)
   } catch (e) {
     notify({
@@ -178,25 +178,73 @@ export const getBestMarket = async ({
   }
 }
 
-export const calculateTradingParameters = (
+// definitions:
+// baseLots = 10 ^ baseLotExponent
+// quoteLots = 10 ^ quoteLotExponent
+// minOrderSize = 10^(baseLotExponent - baseDecimals)
+// minOrderValue = basePrice * minOrderSize
+// priceIncrement =  10^(quoteLotExponent + baseDecimals - baseLotExponent - quoteDecimals)
+
+// derive: baseLotExponent <= max[ basePrice * minOrderSize  < 0.5] (start high -> go low until condition is met)
+// baseLotExponent = 20
+// While (baseLotExponent > 0):
+//     minOrderSize =  10^(baseLotExponent - baseDecimals)
+//     minOrderValue =  basePrice * minOrderSize
+//     if minOrderValue < 0.5:
+//         break;
+
+// Derive: quoteLotExponent <= max[ priceIncrement * basePrice / quotePrice < 0.0001 ]
+// quoteLotExponent = 20
+// While (quoteLotExponent > 0):
+//     priceIncrement =  10^(quoteLotExponent + baseDecimals - baseLotExponent - quoteDecimals)
+//         priceIncrementRelative =  priceIncrement * basePrice / quotePrice
+//     if priceIncrementRelative < 0.0002:
+//         break;
+
+export function calculateTradingParameters(
   basePrice: number,
-  quotePrice: number
-) => {
-  // Calculate the actual price (quote price/base price)
-  const actualPrice = quotePrice / basePrice
+  quotePrice: number,
+  baseDecimals: number,
+  quoteDecimals: number
+) {
+  const MAX_MIN_ORDER_VALUE = 0.5
+  const MIN_PRICE_INCREMENT_RELATIVE = 0.0002
 
-  // Minimum order: $1 worth of base, rounded down to the next 10^(-x)
-  const minOrder =
-    Math.floor((1 / basePrice) * Math.pow(10, 4)) / Math.pow(10, 4)
+  let minOrderSize = 0
+  let priceIncrement = 0
+  let baseLotExponent = 20
+  let quoteLotExponent = 20
 
-  // Price tick: e-4 of the current price, rounded down to the next 10^(-y)
-  const priceTick = Math.floor(
-    (actualPrice * Math.pow(10, 4)) / Math.pow(10, 4)
-  )
+  // Calculate minimum order size
+  do {
+    minOrderSize = Math.pow(10, baseLotExponent - baseDecimals)
+    const minOrderValue = basePrice * minOrderSize
+
+    if (minOrderValue < MAX_MIN_ORDER_VALUE) {
+      break
+    }
+
+    baseLotExponent--
+  } while (baseLotExponent > 0)
+
+  // Calculate price increment
+  do {
+    priceIncrement = Math.pow(
+      10,
+      quoteLotExponent + baseDecimals - baseLotExponent - quoteDecimals
+    )
+    const priceIncrementRelative = (priceIncrement * basePrice) / quotePrice
+
+    if (priceIncrementRelative < MIN_PRICE_INCREMENT_RELATIVE) {
+      break
+    }
+
+    quoteLotExponent--
+  } while (quoteLotExponent > 0)
 
   return {
-    minOrder: minOrder,
-    priceTick: priceTick,
+    minOrder: minOrderSize,
+    priceTick: priceIncrement,
   }
 }