From 6385a35f94de71b3dc335d12ee200c251f22c708 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sehyun=20Chung=20=E2=9C=8C=EF=B8=8E?=
 <41171808+sehyunc@users.noreply.github.com>
Date: Wed, 3 Apr 2024 14:28:05 -0700
Subject: [PATCH] trade: throttle price streams for better ui

---
 .../contexts/PriceContext/price-context.tsx   | 40 +++++++++++--------
 1 file changed, 24 insertions(+), 16 deletions(-)

diff --git a/trade.renegade.fi/contexts/PriceContext/price-context.tsx b/trade.renegade.fi/contexts/PriceContext/price-context.tsx
index 6de4b4ba..d4b85167 100644
--- a/trade.renegade.fi/contexts/PriceContext/price-context.tsx
+++ b/trade.renegade.fi/contexts/PriceContext/price-context.tsx
@@ -1,10 +1,10 @@
 import { Exchange, PriceReporterWs, Token } from "@renegade-fi/renegade-js"
 import React, {
   createContext,
-  useCallback,
   useContext,
   useEffect,
-  useState,
+  useRef,
+  useState
 } from "react"
 
 import { env } from "@/env.mjs"
@@ -38,7 +38,7 @@ export const PriceProvider = ({ children }: { children: React.ReactNode }) => {
     null
   )
   const [prices, setPrices] = useState<Record<string, number>>({})
-  const [lastUpdate, setLastUpdate] = useState<Record<string, number>>({})
+  const lastUpdateRef = useRef<Record<string, number>>({});
   const [attempted, setAttempted] = useState<Record<string, boolean>>({})
   useEffect(() => {
     const priceReporter = new PriceReporterWs(
@@ -50,25 +50,35 @@ export const PriceProvider = ({ children }: { children: React.ReactNode }) => {
     }
   }, [])
 
-  const handleSubscribe = useCallback(
+  const handleSubscribe = 
     (exchange: Exchange, base: string, quote: string, decimals: number) => {
       if (!priceReporter || invalid.includes(base)) return
 
       const topic = getTopic(exchange, base, quote)
       if (attempted[topic]) return
 
-      let lastUpdate = 0
-      const now = Date.now()
-      if (now - lastUpdate <= UPDATE_THRESHOLD_MS) {
-        return
-      }
-      lastUpdate = now
-
       priceReporter.subscribeToTokenPair(
         exchange,
         new Token({ ticker: base }),
         new Token({ ticker: quote || "USDT" }),
         (price) => {
+          const now = Date.now();
+          const lastUpdateTime = lastUpdateRef.current[topic] || 0;
+          console.log("Test: ", {
+            now,
+            topic,
+            lastUpdate: lastUpdateRef.current,
+            lastUpdateTime,
+            UPDATE_THRESHOLD_MS,
+          })
+
+          const randomThreshold = Math.random() * (1500 - 500) + 500;
+          if (now - lastUpdateTime < randomThreshold) {
+            console.log("Skipping update for ", topic, " because it was less than ", UPDATE_THRESHOLD_MS, "ms ago")
+            // If less than 1 second has passed since the last update, do not accept the new price.
+            return;
+          }
+
           setPrices((prevPrices) => {
             if (
               prevPrices[topic]?.toFixed(decimals) !==
@@ -78,13 +88,11 @@ export const PriceProvider = ({ children }: { children: React.ReactNode }) => {
             }
             return prevPrices
           })
-          setLastUpdate((prev) => ({ ...prev, [topic]: Date.now() }))
+          lastUpdateRef.current[topic] = now;
         }
       )
       setAttempted((prev) => ({ ...prev, [topic]: true }))
-    },
-    [attempted, priceReporter]
-  )
+    }
 
   const handleGetPrice = (exchange: Exchange, base: string, quote: string) => {
     const topic = getTopic(exchange, base, quote)
@@ -97,7 +105,7 @@ export const PriceProvider = ({ children }: { children: React.ReactNode }) => {
     quote: string
   ) => {
     const topic = getTopic(exchange, base, quote)
-    return lastUpdate[topic]
+    return lastUpdateRef.current[topic]
   }
 
   return (