From 4cb398869dc90a672e46f3eb1f33b7f710df0ac8 Mon Sep 17 00:00:00 2001
From: Gabriel Kaszewski <gabrielkaszewski@gmail.com>
Date: Thu, 25 Dec 2025 23:41:00 +0100
Subject: [PATCH] feat: add system configuration API endpoint and frontend hook
 for dynamic settings

---
 k-notes-frontend/src/hooks/useConfig.ts | 15 +++++++++++++++
 k-notes-frontend/src/pages/login.tsx    | 16 ++++++++++------
 k-notes-frontend/src/pages/register.tsx | 18 ++++++++++++++++--
 notes-api/src/dto.rs                    |  6 ++++++
 notes-api/src/routes/config.rs          | 14 ++++++++++++++
 notes-api/src/routes/mod.rs             |  3 +++
 6 files changed, 64 insertions(+), 8 deletions(-)
 create mode 100644 k-notes-frontend/src/hooks/useConfig.ts
 create mode 100644 notes-api/src/routes/config.rs

diff --git a/k-notes-frontend/src/hooks/useConfig.ts b/k-notes-frontend/src/hooks/useConfig.ts
new file mode 100644
index 0000000..91f9305
--- /dev/null
+++ b/k-notes-frontend/src/hooks/useConfig.ts
@@ -0,0 +1,15 @@
+
+import { useQuery } from "@tanstack/react-query";
+import { api } from "@/lib/api";
+
+export interface ConfigResponse {
+    allow_registration: boolean;
+}
+
+export function useConfig() {
+    return useQuery<ConfigResponse>({
+        queryKey: ["config"],
+        queryFn: () => api.get("/config"),
+        staleTime: Infinity, // Config rarely changes
+    });
+}
diff --git a/k-notes-frontend/src/pages/login.tsx b/k-notes-frontend/src/pages/login.tsx
index 6ae5723..a7bcc13 100644
--- a/k-notes-frontend/src/pages/login.tsx
+++ b/k-notes-frontend/src/pages/login.tsx
@@ -6,6 +6,7 @@ import { zodResolver } from "@hookform/resolvers/zod";
 import { z } from "zod";
 import { Link } from "react-router-dom";
 import { useLogin } from "@/hooks/use-auth";
+import { useConfig } from "@/hooks/useConfig";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
 import { Card, CardContent, CardDescription, CardFooter, CardHeader, CardTitle } from "@/components/ui/card";
@@ -22,6 +23,7 @@ type LoginFormValues = z.infer<typeof loginSchema>;
 
 export default function LoginPage() {
   const { mutate: login, isPending } = useLogin();
+  const { data: config } = useConfig();
 
   const form = useForm<LoginFormValues>({
     resolver: zodResolver(loginSchema),
@@ -95,12 +97,14 @@ export default function LoginPage() {
           </Form>
         </CardContent>
         <CardFooter className="flex justify-center">
-          <p className="text-sm text-gray-500 dark:text-gray-400">
-            Don't have an account?{" "}
-            <Link to="/register" className="font-semibold text-primary hover:underline">
-              Sign up
-            </Link>
-          </p>
+          {config?.allow_registration !== false && (
+            <p className="text-sm text-gray-500 dark:text-gray-400">
+              Don't have an account?{" "}
+              <Link to="/register" className="font-semibold text-primary hover:underline">
+                Sign up
+              </Link>
+            </p>
+          )}
         </CardFooter>
       </Card>
       <SettingsDialog open={settingsOpen} onOpenChange={setSettingsOpen} dataManagementEnabled={false} />
diff --git a/k-notes-frontend/src/pages/register.tsx b/k-notes-frontend/src/pages/register.tsx
index 523c36b..506ad8b 100644
--- a/k-notes-frontend/src/pages/register.tsx
+++ b/k-notes-frontend/src/pages/register.tsx
@@ -1,11 +1,12 @@
-import { useState } from "react";
+import { useState, useEffect } from "react";
 import { useForm } from "react-hook-form";
 import { Settings } from "lucide-react";
 import { SettingsDialog } from "@/components/settings-dialog";
 import { zodResolver } from "@hookform/resolvers/zod";
 import { z } from "zod";
-import { Link } from "react-router-dom";
+import { Link, useNavigate } from "react-router-dom";
 import { useRegister } from "@/hooks/use-auth";
+import { useConfig } from "@/hooks/useConfig";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
 import { Card, CardContent, CardDescription, CardFooter, CardHeader, CardTitle } from "@/components/ui/card";
@@ -26,6 +27,19 @@ type RegisterFormValues = z.infer<typeof registerSchema>;
 
 export default function RegisterPage() {
   const { mutate: register, isPending } = useRegister();
+  const { data: config, isLoading: isConfigLoading } = useConfig();
+  const navigate = useNavigate();
+
+  useEffect(() => {
+    if (!isConfigLoading && config?.allow_registration === false) {
+      toast.error("Registration is currently disabled");
+      navigate("/login");
+    }
+  }, [config, isConfigLoading, navigate]);
+
+  if (isConfigLoading || config?.allow_registration === false) {
+    return null; // Or a loading spinner
+  }
 
   const form = useForm<RegisterFormValues>({
     resolver: zodResolver(registerSchema),
diff --git a/notes-api/src/dto.rs b/notes-api/src/dto.rs
index c47efde..f1fa9e8 100644
--- a/notes-api/src/dto.rs
+++ b/notes-api/src/dto.rs
@@ -166,3 +166,9 @@ impl From<notes_domain::NoteVersion> for NoteVersionResponse {
         }
     }
 }
+
+/// System configuration response
+#[derive(Debug, Serialize)]
+pub struct ConfigResponse {
+    pub allow_registration: bool,
+}
diff --git a/notes-api/src/routes/config.rs b/notes-api/src/routes/config.rs
new file mode 100644
index 0000000..94e14c3
--- /dev/null
+++ b/notes-api/src/routes/config.rs
@@ -0,0 +1,14 @@
+//! Configuration routes
+
+use axum::{Json, extract::State};
+
+use crate::dto::ConfigResponse;
+use crate::error::ApiResult;
+use crate::state::AppState;
+
+/// Get system configuration
+pub async fn get_config(State(state): State<AppState>) -> ApiResult<Json<ConfigResponse>> {
+    Ok(Json(ConfigResponse {
+        allow_registration: state.config.allow_registration,
+    }))
+}
diff --git a/notes-api/src/routes/mod.rs b/notes-api/src/routes/mod.rs
index 770d18f..59134b8 100644
--- a/notes-api/src/routes/mod.rs
+++ b/notes-api/src/routes/mod.rs
@@ -1,6 +1,7 @@
 //! Route definitions and module structure
 
 pub mod auth;
+pub mod config;
 pub mod import_export;
 pub mod notes;
 pub mod tags;
@@ -40,4 +41,6 @@ pub fn api_v1_router() -> Router<AppState> {
             "/tags/{id}",
             delete(tags::delete_tag).patch(tags::rename_tag),
         )
+        // System Config
+        .route("/config", get(config::get_config))
 }