Сделали несколько кастомных хуков

package-lock.json

@@ -8,6 +8,7 @@
       "name": "store-client",
       "version": "0.0.0",
       "dependencies": {
+        "@tanstack/react-query": "^5.100.14",
         "react": "^19.1.0",
         "react-dom": "^19.1.0"
       },
@@ -1304,6 +1305,32 @@
         "win32"
       ]
     },
+    "node_modules/@tanstack/query-core": {
+      "version": "5.100.14",
+      "resolved": "https://registry.npmjs.org/@tanstack/query-core/-/query-core-5.100.14.tgz",
+      "integrity": "sha512-5X41dGpxgeaHISCRW2oYwcSycZeULZzAunaudXT9ov1KOTj9xwt0CH6hbwqP1/z74ZWF7rYFnDpyYH07XFcZew==",
+      "license": "MIT",
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/sponsors/tannerlinsley"
+      }
+    },
+    "node_modules/@tanstack/react-query": {
+      "version": "5.100.14",
+      "resolved": "https://registry.npmjs.org/@tanstack/react-query/-/react-query-5.100.14.tgz",
+      "integrity": "sha512-oOr6aRdSFEwWhzxEkD/9ZcItM3+LjBSkeVmadWKwUssAHTsqd/7bOjWrX4AbvEkoEhgAxzN0Xk6H/aYzXiYBAw==",
+      "license": "MIT",
+      "dependencies": {
+        "@tanstack/query-core": "5.100.14"
+      },
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/sponsors/tannerlinsley"
+      },
+      "peerDependencies": {
+        "react": "^18 || ^19"
+      }
+    },
     "node_modules/@types/babel__core": {
       "version": "7.20.5",
       "resolved": "https://registry.npmjs.org/@types/babel__core/-/babel__core-7.20.5.tgz",

package.json

@@ -4,12 +4,13 @@
   "version": "0.0.0",
   "type": "module",
   "scripts": {
-    "dev": "vite", 
+    "dev": "vite",
     "build": "vite build",
     "lint": "eslint .",
     "preview": "vite preview"
   },
   "dependencies": {
+    "@tanstack/react-query": "^5.100.14",
     "react": "^19.1.0",
     "react-dom": "^19.1.0"
   },

src/App.jsx

@@ -1,67 +1,94 @@
-import React, { useState, useReducer, useRef, memo } from 'react'
+import React, {useState, useEffect, useRef } from 'react'
+//import { useQuery } from '@tanstack/react-query'
 
-function tasksReducer(state, action) {
+function useWindowWidth() {
-    switch(action.type) {
+    const [width,setWidth] = useState(window.innerWidth)
-        case 'ADD_TASK':
+    
-            return [...state, action.payload]
+    useEffect(() => {
-        case 'TOGGLE_TASK':
+        const handleResize = () => setWidth(window.innerWidth);
-            return state.map(task => task.id === action.payload ? {...task, complite: !task.complite} : task)
+        window.addEventListener('resize',handleResize);
-        case 'REMOVE_TASK':
+        return () => window.removeEventListener('resize',handleResize);
-            return state.filter(task => task.id !== action.payload)
+    },[])
-        default:
+    
-            return state
+    return width
-    }
 }
 
-const TaskList = memo(function TaskList({tasks, onToggle, onRemove}) {
+function useLocalStorage(key, initValue) {
-    console.log("Rendred")
+    const [value, setValue] = useState(()=>{
-    return (
+        const stored = localStorage.getItem(key);
-        <ul>
+        return stored !== null ? JSON.parse(stored) : initValue
-        {tasks.map(({id, text, complite}) => (
+    })
-                <li key={id}
-                    style={{textDecoration: complite ? 'line-through' : 'none' }}>
-                    <input type="checkbox" checked={complite} onChange={()=>onToggle(id)} />
-                    {text}
-                    <button onClick={()=> onRemove(id)} style={{marginLeft: 10}}>
-                        Удалить
-                    </button>
-                </li>
-            ))}
-        </ul>
-    )
-})
-
-function App() {
-    const [tasks, dispatch] = useReducer(tasksReducer,[])
-    const [input,setInput] = useState('')
-    const [error,setError] = useState('')
-    const inputRef = useRef(null)
     
-    const addTask = () => {
+    useEffect(() => {
-        if (input.trim() === '') {
+        localStorage.setItem(key, JSON.stringify(value))
-            setError('Пустой текст задачи')
+    },[key, value])
-            return
+    
+    return [value,setValue]
+}
+/*
+function useUserData(userId) {
+    return useQuery(
+        ['user',userId],
+        () => fetch(`/api/user/${userId}`).then(res => res.json()),
+        {refetchOnWindowFocus: false}
+    )
+}*/
+
+function useInput(initValue, validate) {
+    const [value, setValue] = useState(initValue);
+    const [error, setError] = useState(null);
+    
+    const onChange = e => {
+        const newValue = e.target.value
+        setValue(newValue)
+        if (validate) {
+            const validationResult = validate(newValue)
+            setError(validationResult)
         }
-        setError('')
-        dispatch({
-            type: 'ADD_TASK',
-            payload: {id: Date.now(), text: input.trim(), complite: false }
-        })
-        setInput('')
-        inputRef.current.focus()
     }
     
+    return { value, error, onChange }
+}
+
+function useInterval(callback, delay) {
+    const savedCallback = useRef()
+    
+    useEffect(()=>{
+        savedCallback.current = callback
+    },[callback]);
+    
+    useEffect(()=>{
+        if (delay == null) return
+        const id = setInterval(()=>{
+            savedCallback.current()
+        },delay);
+        return () => clearInterval(id);
+    },[delay])
+}
+
+function App() {
+    const width = useWindowWidth();
+    const [theme, setTheme] = useLocalStorage('theme','light');
+    
+    const username = useInput(
+        '',
+        value => value.length < 3 ? 'минимум 3 символа' : null
+    )
+    
 	return (
-		<div style={{padding: 20}}>
+		<>
-			<h1>Список дел</h1>
+			<h1>Hello, React!{width}</h1>
-			<input ref={inputRef} value={input} onChange={e => setInput(e.target.value)} />
+            <button onClick={()=>{
-			<button onClick={addTask}>Добавить</button>
+                setTheme(theme === 'light' ? 'dark' : 'light')
-            {error && <p style={{color: 'red'}}>{error}</p>}
+            }}>
-            
+                Сменить тему
-            <TaskList tasks={tasks} 
+            </button>
-                onToggle={id => dispatch({type: 'TOGGLE_TASK', payload: id})}
+            <p><input type="text" 
-                onRemove={id => dispatch({type: 'REMOVE_TASK', payload: id})} />
+                value={username.value} 
-		</div>
+                onChange={username.onChange} />
+                { username.error ? username.error : '' }
+            </p>
+		</>
 	)
 }