added partial settings updates

backend/src/handlers/config.rs

@@ -2,7 +2,12 @@ use axum::{Json, extract::State, http::HeaderMap, response::IntoResponse};
 use std::{fs, sync::Arc};
 use tracing::error;
 
-use crate::{AppState, auth::check_auth, error::AppError, models::SiteConfig};
+use crate::{
+    AppState,
+    auth::check_auth,
+    error::AppError,
+    models::{SiteConfig, SiteConfigPatch},
+};
 
 pub async fn get_config(State(state): State<Arc<AppState>>) -> impl IntoResponse {
     let config_path = state.data_dir.join("config.json");
@@ -17,12 +22,26 @@ pub async fn get_config(State(state): State<Arc<AppState>>) -> impl IntoResponse
 pub async fn update_config(
     State(state): State<Arc<AppState>>,
     headers: HeaderMap,
-    Json(payload): Json<SiteConfig>,
+    Json(patch): Json<SiteConfigPatch>,
 ) -> Result<Json<SiteConfig>, AppError> {
     check_auth(&headers, &state.admin_token)?;
 
     let config_path = state.data_dir.join("config.json");
-    let config_str = serde_json::to_string_pretty(&payload).map_err(|e| {
+    let mut config: SiteConfig = fs::read_to_string(&config_path)
+        .ok()
+        .and_then(|c| serde_json::from_str(&c).ok())
+        .unwrap_or_default();
+
+    if let Some(v) = patch.title { config.title = v; }
+    if let Some(v) = patch.subtitle { config.subtitle = v; }
+    if let Some(v) = patch.welcome_title { config.welcome_title = v; }
+    if let Some(v) = patch.welcome_subtitle { config.welcome_subtitle = v; }
+    if let Some(v) = patch.footer { config.footer = v; }
+    if let Some(v) = patch.favicon { config.favicon = v; }
+    if let Some(v) = patch.theme { config.theme = v; }
+    if let Some(v) = patch.custom_css { config.custom_css = v; }
+
+    let config_str = serde_json::to_string_pretty(&config).map_err(|e| {
         error!("Serialization error: {}", e);
         AppError::Internal("Serialization error".to_string(), Some(e.to_string()))
     })?;
@@ -32,5 +51,5 @@ pub async fn update_config(
         AppError::Internal("Write error".to_string(), Some(e.to_string()))
     })?;
 
-    Ok(Json(payload))
+    Ok(Json(config))
 }

backend/src/models.rs

@@ -29,6 +29,26 @@ impl Default for SiteConfig {
     }
 }
 
+#[derive(Deserialize, Default)]
+pub struct SiteConfigPatch {
+    #[serde(default)]
+    pub title: Option<String>,
+    #[serde(default)]
+    pub subtitle: Option<String>,
+    #[serde(default)]
+    pub welcome_title: Option<String>,
+    #[serde(default)]
+    pub welcome_subtitle: Option<String>,
+    #[serde(default)]
+    pub footer: Option<String>,
+    #[serde(default)]
+    pub favicon: Option<String>,
+    #[serde(default)]
+    pub theme: Option<String>,
+    #[serde(default)]
+    pub custom_css: Option<String>,
+}
+
 #[derive(Serialize, Deserialize, Clone, Default)]
 pub struct PostMeta {
     pub date: NaiveDate,