diff --git a/.gitignore b/.gitignore
index e364f4b..47a5649 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,7 +2,7 @@
 
 #Vscode
 .vscode
-
+.idea
 # dependencies
 node_modules/
 
diff --git a/app/_layout.tsx b/app/_layout.tsx
index 3d651a3..e4f5bf0 100644
--- a/app/_layout.tsx
+++ b/app/_layout.tsx
@@ -1,27 +1,73 @@
-import { DarkTheme, DefaultTheme, ThemeProvider } from '@react-navigation/native';
-import { Stack } from 'expo-router';
-import { StatusBar } from 'expo-status-bar';
-import 'react-native-reanimated';
-
-import { useColorScheme } from '@/hooks/use-color-scheme';
+import {
+  DarkTheme,
+  DefaultTheme,
+  ThemeProvider,
+} from "@react-navigation/native";
+import { Stack } from "expo-router";
+import { StatusBar } from "expo-status-bar";
+import "react-native-reanimated";
+import { useEffect, useState } from "react";
+import { onAuthStateChanged, User } from "firebase/auth";
+import { auth, db } from "../firebase_config";
+import { useRouter } from "expo-router";
+import { useColorScheme } from "@/hooks/use-color-scheme";
+import { doc, getDoc } from "firebase/firestore";
 
 export const unstable_settings = {
-  anchor: '(tabs)',
+  anchor: "(tabs)",
 };
 
 export default function RootLayout() {
   const colorScheme = useColorScheme();
+  const router = useRouter();
+  const [user, setUser] = useState<User | null>(null);
+  const [userRole, setUserRole] = useState<string | null>(null);
+
+  useEffect(() => {
+    const unsubscribe = onAuthStateChanged(auth, async (currentUser) => {
+      setUser(currentUser);
+      if (!currentUser) {
+        router.replace("/login/login");
+        return;
+      }
+
+      const userDocRef = doc(db, "user", currentUser.uid);
+      const userDoc = await getDoc(userDocRef);
+
+      if (!userDoc.exists()) {
+        router.replace("/login/login");
+        return;
+      }
+
+      const { role } = userDoc.data();
+      setUser(currentUser);
+      setUserRole(role);
+
+      if (role === "chef") {
+        router.replace("/(tabs)");
+      } else if (role === "responsable") {
+        router.replace("/login/login");
+      } else {
+        router.replace("/login/login");
+      }
+    });
+
+    return unsubscribe;
+  }, []);
 
   return (
 
-    <ThemeProvider value={colorScheme === 'dark' ? DarkTheme : DefaultTheme}>
+    <ThemeProvider value={colorScheme === "dark" ? DarkTheme : DefaultTheme}>
       <Stack>
         <Stack.Screen name="(tabs)" options={{ headerShown: false }} />
         <Stack.Screen name="selectChantier" options={{ headerShown: false }}/>
-        <Stack.Screen name="modal" options={{ presentation: 'modal', title: 'Modal' }} />
+        <Stack.Screen
+          name="modal"
+          options={{ presentation: "modal", title: "Modal" }}
+        />
+        <Stack.Screen name="login" options={{ headerShown: false }} />
       </Stack>
       <StatusBar style="auto" />
     </ThemeProvider>
-
   );
 }
diff --git a/app/login/login.tsx b/app/login/login.tsx
new file mode 100644
index 0000000..29efb06
--- /dev/null
+++ b/app/login/login.tsx
@@ -0,0 +1,76 @@
+import React, { useState } from "react";
+import { View, Text, TextInput, Button, StyleSheet } from "react-native";
+import {
+  signInWithEmailAndPassword,
+  createUserWithEmailAndPassword,
+} from "firebase/auth";
+import { doc, setDoc } from "firebase/firestore";
+import { auth, db } from "../../firebase_config";
+import { router } from "expo-router";
+
+const DEFAULT_ROLE = "resp";
+
+const LoginScreen: React.FC = () => {
+  const [email, setEmail] = useState<string>("");
+  const [password, setPassword] = useState<string>("");
+
+  const handleLogin = async () => {
+    try {
+      await signInWithEmailAndPassword(auth, email, password);
+      router.replace("/(tabs)");
+    } catch (error: any) {
+      alert(error.message);
+    }
+  };
+
+  const handleRegister = async () => {
+    try {
+      await createUserWithEmailAndPassword(auth, email, password);
+      router.replace("/(tabs)");
+    } catch (error: any) {
+      alert(error.message);
+    }
+  };
+
+  return (
+    <View style={styles.container}>
+      <Text style={styles.title}>Se connecter / S'incrire</Text>
+      <TextInput
+        style={styles.input}
+        placeholder="Email"
+        value={email}
+        onChangeText={setEmail}
+        autoCapitalize="none"
+      />
+      <TextInput
+        style={styles.input}
+        placeholder="Mot de passe"
+        value={password}
+        onChangeText={setPassword}
+        secureTextEntry
+      />
+      <Button title="Se connecter" onPress={handleLogin} />
+      <View style={{ height: 10 }} />
+      <Button title="S'incrire" onPress={handleRegister} />
+    </View>
+  );
+};
+
+export default LoginScreen;
+
+const styles = StyleSheet.create({
+  container: { flex: 1, justifyContent: "center", padding: 20 },
+  title: {
+    fontSize: 22,
+    fontWeight: "bold",
+    marginBottom: 20,
+    textAlign: "center",
+  },
+  input: {
+    borderWidth: 1,
+    borderColor: "#ccc",
+    borderRadius: 8,
+    padding: 10,
+    marginBottom: 10,
+  },
+});
diff --git a/firebase_config.js b/firebase_config.js
new file mode 100644
index 0000000..9d64c64
--- /dev/null
+++ b/firebase_config.js
@@ -0,0 +1,23 @@
+// Import the functions you need from the SDKs you need
+import { initializeApp } from "firebase/app";
+import { getAuth } from 'firebase/auth';
+import { getFirestore } from "firebase/firestore";
+
+// TODO: Add SDKs for Firebase products that you want to use
+// https://firebase.google.com/docs/web/setup#available-libraries
+
+// Your web app's Firebase configuration
+const firebaseConfig = {
+  apiKey: "AIzaSyCSD4FNL-j6mEudYfnu1NV7k63a8TdHvPU",
+  authDomain: "mmm-projet-ddf1f.firebaseapp.com",
+  projectId: "mmm-projet-ddf1f",
+  storageBucket: "mmm-projet-ddf1f.firebasestorage.app",
+  messagingSenderId: "328867267019",
+  appId: "1:328867267019:web:f21d40680e63fb56f5b64e"
+};
+
+// Initialize Firebase
+const app = initializeApp(firebaseConfig);
+
+export const auth = getAuth(app);
+export const db = getFirestore(app);
\ No newline at end of file