added register screen

lib/client.dart

@@ -20,8 +20,8 @@ class ApiClient {
     }
   }
 
-  Map<String, String> headers({bool forGet = false}) {
+  Map<String, String> headers({bool forGet = false, bool forLogin = false}) {
-    if (token == null) {
+    if (token == null && !forLogin) {
       throw Exception('Not logged in');
     }
 
@@ -61,11 +61,11 @@ class ApiClient {
     return _jsonDecode(response);
   }
 
-  Future<Map<String, dynamic>> post(String path, Map<String, dynamic> body) async {
+  Future<Map<String, dynamic>> post(String path, Map<String, dynamic> body, {bool forLogin = false}) async {
     final response = await httpClient.post(
       Uri.parse('$baseUrl$path'),
       body: jsonEncode(body),
-      headers: headers(),
+      headers: headers(forLogin: forLogin),
     );
 
     if (response.statusCode != 200) {
@@ -198,4 +198,17 @@ class ApiClient {
     };
     await patch("/entry/$id", entry);
   }
+
+  Future<void> register(String username, String password) async {
+    try {
+      await post("/user", {
+          "username": username,
+          "password": password,
+        },
+        forLogin: true,
+      );
+    } catch (e) {
+      throw Exception("Failed to register");
+    }
+  }
 }

lib/screens/login.dart

@@ -1,6 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:fooder_web/screens/based.dart';
 import 'package:fooder_web/screens/main.dart';
+import 'package:fooder_web/screens/register.dart';
 
 
 class LoginScreen extends BasedScreen {
@@ -113,10 +114,27 @@ class _LoginScreen extends State<LoginScreen> {
                 controller: passwordController,
                 onFieldSubmitted: (_) => _login()
               ),
-               FilledButton(
+              Padding(
+                padding: const EdgeInsets.symmetric(vertical: 10),
+                child: FilledButton(
                   onPressed: _login,
                   child: const Text('Login'),
-              )
+                ),
+              ),
+              Padding(
+                padding: const EdgeInsets.symmetric(vertical: 10),
+                child: TextButton(
+                  onPressed: () {
+                    Navigator.push(
+                      context,
+                      MaterialPageRoute(
+                        builder: (context) => RegisterScreen(apiClient: widget.apiClient),
+                      ),
+                    );
+                  },
+                  child: const Text('Don\'t have an account? Register here!'),
+                ),
+              ),
             ],
           ),
         ),

lib/screens/register.dart

@@ -0,0 +1,117 @@
+import 'package:flutter/material.dart';
+import 'package:fooder_web/screens/based.dart';
+
+
+class RegisterScreen extends BasedScreen {
+  const RegisterScreen({super.key, required super.apiClient});
+
+  @override
+  State<RegisterScreen> createState() => _RegisterScreen();
+}
+
+
+class _RegisterScreen extends State<RegisterScreen> {
+  final usernameController = TextEditingController();
+  final passwordController = TextEditingController();
+  final passwordConfirmController = TextEditingController();
+
+  @override
+  void dispose() {
+    usernameController.dispose();
+    passwordController.dispose();
+    passwordConfirmController.dispose();
+    super.dispose();
+  }
+
+  void showError(String message)
+  {
+    ScaffoldMessenger.of(context).showSnackBar(
+      SnackBar(
+        content: Text(message, textAlign: TextAlign.center),
+        backgroundColor: Theme.of(context).colorScheme.error,
+      ),
+    );
+  }
+
+  void showText(String text)
+  {
+    ScaffoldMessenger.of(context).showSnackBar(
+      SnackBar(
+        content: Text(text, textAlign: TextAlign.center),
+        backgroundColor: Theme.of(context).colorScheme.primary,
+      ),
+    );
+  }
+
+  void popMeDady() {
+    Navigator.pop(context);
+  }
+
+  // login client when button pressed
+  Future<void> _register() async {
+    if (passwordController.text != passwordConfirmController.text) {
+      showError("Passwords don't match");
+      return;
+    }
+
+    try {
+      await widget.apiClient.register(
+        usernameController.text,
+        passwordController.text,
+      );
+      showText("Created account. You can now log in.");
+      popMeDady();
+    } on Exception catch (e) {
+      showError(e.toString());
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
+        title: const Text("FOODER"),
+      ),
+      body: Center(
+        child: Container(
+          constraints: const BoxConstraints(maxWidth: 600),
+          padding: const EdgeInsets.all(10),
+          child: Column(
+            mainAxisAlignment: MainAxisAlignment.center,
+            children: <Widget>[
+              TextFormField(
+                decoration: const InputDecoration(
+                  labelText: 'Username',
+                ),
+                controller: usernameController,
+              ),
+              TextFormField(
+                obscureText: true,
+                decoration: const InputDecoration(
+                  labelText: 'Password',
+                ),
+                controller: passwordController,
+              ),
+              TextFormField(
+                obscureText: true,
+                decoration: const InputDecoration(
+                  labelText: 'Confirm password',
+                ),
+                controller: passwordConfirmController,
+                onFieldSubmitted: (_) => _register()
+              ),
+              Padding(
+                padding: const EdgeInsets.symmetric(vertical: 10),
+                child: FilledButton(
+                  onPressed: _register,
+                  child: const Text('Register'),
+                )
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}