add auth to backend and frontend

frontend/src/App.tsx

@@ -4,7 +4,7 @@ import LatestTemperature from "@/components/latest-temperature"
 import TemperatureHistory from "@/components/temperature-history"
 import TemperaturePlot from "@/components/temperature-plot"
 import RegisterForm from './components/register-form'
-// import { Button } from "@/components/ui/button"
+import { AuthProvider } from './contexts/auth-context'
 
 
 
@@ -12,18 +12,20 @@ import RegisterForm from './components/register-form'
 function App() {
     return (
         <ThemeProvider defaultTheme="dark" storageKey="vite-ui-theme">
-            <main className="min-h-screen bg-background p-6 w-full">
-                <div>
-                    <RegisterForm />
-                </div>
-                <div className="w-full mx-auto space-y-2">
-                    <TemperaturePlot />
-                    <div className="grid grid-cols-4 gap-6">
-                        <LatestTemperature />
-                        <TemperatureHistory />
+            <AuthProvider>
+                <main className="min-h-screen bg-background p-6 w-full">
+                    <div>
+                        <RegisterForm />
                     </div>
-                </div>
-            </main>
+                    <div className="w-full mx-auto space-y-2">
+                        <TemperaturePlot />
+                        <div className="grid grid-cols-4 gap-6">
+                            <LatestTemperature />
+                            <TemperatureHistory />
+                        </div>
+                    </div>
+                </main>
+            </AuthProvider>
         </ThemeProvider>
     )
 }

frontend/src/contexts/auth-context.tsx

@@ -0,0 +1,81 @@
+import {
+    createContext,
+    useState,
+    useEffect,
+} from "react"
+
+import type { ReactNode } from "react"
+
+type User = {
+    id: number
+    email: string
+    create_at: string
+}
+
+type AuthContextType = {
+    user: User | null
+    isAuthenticated: boolean
+    login: (email: string, passwor: string) => Promise<void>
+    logout: () => void
+    isLoading: boolean
+}
+
+export const AuthContext = createContext<AuthContextType | null>(null)
+
+export function AuthProvider({ children }: { children: ReactNode }) {
+    const [user, setUser] = useState<User | null>(null)
+    const [isLoading, setIsLoading] = useState(true)
+
+    useEffect(() => {
+        checkAuth()
+    }, [])
+
+    async function checkAuth() {
+        try {
+            const res = await fetch("/api/me", {
+                credentials: "include",
+            })
+            if (res.ok) {
+                const data = await res.json()
+                setUser(data.user)
+            }
+        }
+        catch {
+            setUser(null)
+        }
+        finally {
+            setIsLoading(false)
+        }
+    }
+
+    async function login(email: string, password: string) {
+        const res = await fetch("/api/login", {
+            method: "POST",
+            credentials: "include",
+            headers: { "Content-Type": "application/json" },
+            body: JSON.stringify({ email, password })
+        })
+
+        if (!res.ok) {
+            const msg = await res.text()
+            throw new Error(msg || "Invalid credentials")
+        }
+
+        const data = await res.json()
+        setUser(data.user)
+    }
+
+    async function logout() {
+        await fetch("api/logout", {
+            method: "POST",
+            credentials: "include",
+        })
+        setUser(null)
+    }
+
+    return (
+        <AuthContext.Provider value={{ user, isAuthenticated: !!user, login, logout, isLoading }}>
+            {children}
+        </AuthContext.Provider>
+    )
+}

frontend/src/hooks/use-auth.tsx

@@ -0,0 +1,8 @@
+import { AuthContext } from "@/contexts/auth-context"
+import { useContext } from "react"
+
+export function useAuth() {
+    const ctx = useContext(AuthContext)
+    if (!ctx) throw new Error("useAuth must be used within AuthProvider")
+    return ctx
+}