[Chat] iOS 모바일에서 init 시점에 infinite scroll 로직 실행되는 오류 수정

packages/chat/src/chat/chat.tsx

@@ -1,6 +1,12 @@
 import { IncomingMessage } from 'http'
 
-import React, { useCallback, useEffect, useMemo, useReducer } from 'react'
+import React, {
+  useCallback,
+  useEffect,
+  useMemo,
+  useReducer,
+  useRef,
+} from 'react'
 import { StaticIntersectionObserver as IntersectionObserver } from '@titicaca/intersection-observer'
 import { useUserAgentContext } from '@titicaca/react-contexts'
 import { closeKeyboard } from '@titicaca/triple-web-to-native-interfaces'
@@ -25,7 +31,6 @@ import { useChat } from './chat-context'
 import { useChatMessage } from './use-chat-message'
 import { getChatListHeight, useScrollContext } from './scroll-context'
 
-const MINIMUM_INTERSECTING_TIME = 3000
 export const CHAT_CONTAINER_ID = 'chat-inner-container'
 
 export interface ChatProps {
@@ -90,6 +95,8 @@ export const Chat = ({
     dispatch,
   ] = useReducer(ChatReducer, initialChatState)
 
+  const isScrollReady = useRef(false)
+
   const { os } = useUserAgentContext()
   const isIos = useMemo(() => os.name === 'iOS', [os.name])
   const updateUnread = useCallback(async () => {
@@ -216,10 +223,16 @@ export const Chat = ({
   const handleChangeLastMessageId = async () => {
     await updateUnread()
     scrollToBottom()
+
+    if (!isScrollReady.current) {
+      isScrollReady.current = true
+    }
   }
 
   useEffect(() => {
-    void handleChangeLastMessageId()
+    if (lastMessageId) {
+      void handleChangeLastMessageId()
+    }
   }, [lastMessageId])
 
   useEffect(() => {
@@ -228,17 +241,19 @@ export const Chat = ({
 
   const onChangeScroll = async ({
     isIntersecting,
-    time,
   }: IntersectionObserverEntry) => {
-    const prevScrollY = getChatListHeight()
-    if (isIntersecting && time >= MINIMUM_INTERSECTING_TIME && hasPrevMessage) {
-      const pastMessages = await fetchPastMessages()
+    if (isIntersecting) {
+      const prevScrollY = getChatListHeight()
 
-      await dispatch({
-        action: ChatActions.PAST,
-        messages: pastMessages,
-      })
-      setScrollY(prevScrollY)
+      if (isScrollReady.current && hasPrevMessage) {
+        const pastMessages = await fetchPastMessages()
+
+        await dispatch({
+          action: ChatActions.PAST,
+          messages: pastMessages,
+        })
+        setScrollY(prevScrollY)
+      }
     }
   }