Ignore pubspec.lock

.gitignore

@@ -44,3 +44,5 @@ app.*.map.json
 /android/app/debug
 /android/app/profile
 /android/app/release
+
+pubspec.lock

lib/pages/AuthPage.dart

@@ -0,0 +1,97 @@
+import 'package:diary/RegisterPage.dart';
+import 'package:firebase_auth/firebase_auth.dart';
+import 'package:flutter/material.dart';
+
+class AuthPage extends StatefulWidget {
+  const AuthPage({Key? key}) : super(key: key);
+  @override
+  _AuthPage createState() => _AuthPage();
+}
+
+class _AuthPage extends State<AuthPage> {
+  final TextEditingController _emailController = TextEditingController();
+  final TextEditingController _passwordController = TextEditingController();
+  String _emailError = "";
+  String _passwordError = "";
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      debugShowCheckedModeBanner: false,
+      title: "Dairy",
+      home: Scaffold(
+        appBar: AppBar(
+          title: const Text('Login'),
+        ),
+        body: Center(
+          child: Column(
+            children: [
+              TextField(
+                controller: _emailController,
+                onChanged: (v) {
+                  setState(() {
+                    _emailError = "";
+                  });
+                },
+                keyboardType: TextInputType.emailAddress,
+                decoration: InputDecoration(
+                  labelText: "Email",
+                  errorText: _emailError == "" ? null : _emailError,
+                ),
+              ),
+              TextField(
+                controller: _passwordController,
+                onChanged: (v) {
+                  setState(() {
+                    _passwordError = "";
+                  });
+                },
+                obscureText: true,
+                enableSuggestions: false,
+                autocorrect: false,
+                decoration: InputDecoration(
+                  labelText: "Password",
+                  errorText: _passwordError == "" ? null : _passwordError,
+                ),
+              ),
+              Builder(builder: (context) {
+                return TextButton(
+                    onPressed: () => register(context),
+                    child: Text("Don't have an account? Register"));
+              }),
+              ElevatedButton(onPressed: submit, child: Text("SUBMIT"))
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  void register(BuildContext context) {
+    Navigator.of(context)
+        .push(MaterialPageRoute(builder: (context) => RegisterPage()));
+  }
+
+  void submit() async {
+    String email = _emailController.text;
+    String password = _passwordController.text;
+    try {
+      UserCredential userCredential = await FirebaseAuth.instance
+          .signInWithEmailAndPassword(email: email, password: password);
+    } on FirebaseAuthException catch (e) {
+      if (e.code == 'user-not-found' || e.code == 'invalid-email') {
+        setState(() {
+          _emailError = "Couldn't find such an email, try registering?";
+        });
+      } else if (e.code == 'wrong-password') {
+        setState(() {
+          _passwordError = "Incorrect password.";
+        });
+      } else {
+        setState(() {
+          _emailError = e.code;
+        });
+      }
+    }
+  }
+}

lib/pages/HomePage.dart

@@ -0,0 +1,57 @@
+import 'package:cloud_firestore/cloud_firestore.dart';
+import 'package:firebase_auth/firebase_auth.dart';
+import 'package:flutter/material.dart';
+
+class HomePage extends StatefulWidget {
+  const HomePage({Key? key}) : super(key: key);
+  @override
+  _HomePage createState() => _HomePage();
+}
+
+class _HomePage extends State<HomePage> {
+  CollectionReference usersRef = FirebaseFirestore.instance.collection('users');
+  User firebaseUser = FirebaseAuth.instance.currentUser!;
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      debugShowCheckedModeBanner: false,
+      title: "Dairy",
+      home: Scaffold(
+        appBar: AppBar(
+          title: const Text("Welcome"),
+          actions: <Widget>[
+            PopupMenuButton<String>(onSelected: (s) {
+              if (s == 'Logout') {
+                FirebaseAuth.instance.signOut();
+              }
+            }, itemBuilder: (BuildContext context) {
+              return {"Logout"}.map((String choice) {
+                return PopupMenuItem<String>(
+                  child: Text(choice),
+                  value: choice,
+                );
+              }).toList();
+            })
+          ],
+        ),
+        body: Center(
+          child: FutureBuilder(
+            future: usersRef.doc(firebaseUser.uid).get(),
+            builder: (BuildContext context,
+                AsyncSnapshot<DocumentSnapshot> snapshot) {
+              if (snapshot.connectionState == ConnectionState.done) {
+                Map<String, dynamic> data =
+                    snapshot.data!.data() as Map<String, dynamic>;
+                String name = data['name'];
+                return Text(name);
+              } else {
+                return Text("Loading");
+              }
+            },
+          ),
+        ),
+      ),
+    );
+  }
+}

lib/pages/RegisterPage.dart

@@ -0,0 +1,155 @@
+import 'package:diary/AuthPage.dart';
+import 'package:firebase_auth/firebase_auth.dart';
+import 'package:cloud_firestore/cloud_firestore.dart';
+import 'package:flutter/material.dart';
+
+class RegisterPage extends StatefulWidget {
+  const RegisterPage({Key? key}) : super(key: key);
+  @override
+  _RegisterPage createState() => _RegisterPage();
+}
+
+class _RegisterPage extends State<RegisterPage> {
+  final TextEditingController _nameController = TextEditingController();
+  final TextEditingController _emailController = TextEditingController();
+  final TextEditingController _passwordController = TextEditingController();
+  final TextEditingController _confirmController = TextEditingController();
+  String _nameError = "";
+  String _emailError = "";
+  String _passwordError = "";
+  String _confirmError = "";
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      debugShowCheckedModeBanner: false,
+      title: "Dairy",
+      home: Scaffold(
+        appBar: AppBar(
+          title: const Text('Login'),
+        ),
+        body: Center(
+          child: Column(
+            children: [
+              TextField(
+                controller: _nameController,
+                onChanged: (v) {
+                  setState(() {
+                    _nameError = "";
+                  });
+                },
+                keyboardType: TextInputType.name,
+                decoration: InputDecoration(
+                  labelText: "Name",
+                  errorText: _nameError == "" ? null : _nameError,
+                ),
+              ),
+              TextField(
+                controller: _emailController,
+                onChanged: (v) {
+                  setState(() {
+                    _emailError = "";
+                  });
+                },
+                keyboardType: TextInputType.emailAddress,
+                decoration: InputDecoration(
+                  labelText: "Email",
+                  errorText: _emailError == "" ? null : _emailError,
+                ),
+              ),
+              TextField(
+                controller: _passwordController,
+                onChanged: (v) {
+                  setState(() {
+                    _passwordError = "";
+                  });
+                },
+                obscureText: true,
+                enableSuggestions: false,
+                autocorrect: false,
+                decoration: InputDecoration(
+                  labelText: "Password",
+                  errorText: _passwordError == "" ? null : _passwordError,
+                ),
+              ),
+              TextField(
+                controller: _confirmController,
+                onChanged: (v) {
+                  setState(() {
+                    _confirmError = "";
+                  });
+                },
+                obscureText: true,
+                enableSuggestions: false,
+                autocorrect: false,
+                decoration: InputDecoration(
+                  labelText: "Confirm Password",
+                  errorText: _confirmError == "" ? null : _confirmError,
+                ),
+              ),
+              Builder(
+                builder: (context) {
+                  return TextButton(
+                      onPressed: () => login(context), child: Text("Have an account? Login"));
+                }
+              ),
+              ElevatedButton(onPressed: submit, child: Text("SUBMIT"))
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  void login(BuildContext context) {
+    Navigator.of(context).push(MaterialPageRoute(builder: (context) => AuthPage()));
+  }
+
+  Future<void> submit() async {
+    String name = _nameController.text;
+    String email = _emailController.text;
+    String password = _passwordController.text;
+    String confirm = _confirmController.text;
+    if (name.isEmpty) {
+      setState(() {
+        _nameError = "Name is required.";
+      });
+      return;
+    }
+    if (!RegExp(r"^[a-zA-Z0-9.a-zA-Z0-9.!#$%&'*+-/=?^_`{|}~]+@[a-zA-Z0-9]+\.[a-zA-Z]+").hasMatch(email)) {
+      setState(() {
+        _emailError = "Invalid email.";
+      });
+      return;
+    }
+    if (password != confirm) {
+      setState(() {
+        _confirmError = "Passwords don't match.";
+      });
+      return;
+    }
+    try {
+      UserCredential userCredential = await FirebaseAuth
+          .instance
+          .createUserWithEmailAndPassword(email: email, password: password);
+      User firebaseUser = FirebaseAuth.instance.currentUser!;
+      CollectionReference usersCollection = FirebaseFirestore.instance.collection("users");
+      usersCollection.doc(firebaseUser.uid).set({
+        'name': name
+      });
+    } on FirebaseAuthException catch (e) {
+      if (e.code == "weak-password") {
+        setState(() {
+          _passwordError = "Password too weak.";
+        });
+      } else if (e.code == "email-already-in-use") {
+        setState(() {
+          _emailError = "Email is already in use, try logging in?";
+        });
+      }
+    } catch (e) {
+      print(e);
+    }
+  }
+
+}