Add helper for setting config values efficiently

Cargo.lock

@@ -976,6 +976,7 @@ dependencies = [
  "lexical-sort",
  "libcosmic",
  "log",
+ "paste",
  "rust-embed",
  "serde",
  "systemicons",

Cargo.toml

@@ -10,6 +10,7 @@ env_logger = "0.10"
 lazy_static = "1"
 lexical-sort = "0.3.1"
 log = "0.4"
+paste = "1.0"
 serde = { version = "1", features = ["serde_derive"] }
 tokio = { version = "1" }
 trash = "3.2.0"

src/main.rs

@@ -416,13 +416,40 @@ impl Application for App {
 
     /// Handle application events here.
     fn update(&mut self, message: Self::Message) -> Command<Self::Message> {
+        // Helper for updating config values efficiently
+        macro_rules! config_set {
+            ($name: ident, $value: expr) => {
+                match &self.config_handler {
+                    Some(config_handler) => {
+                        match paste::paste! { self.config.[<set_ $name>](config_handler, $value) } {
+                            Ok(_) => {}
+                            Err(err) => {
+                                log::warn!(
+                                    "failed to save config {:?}: {}",
+                                    stringify!($name),
+                                    err
+                                );
+                            }
+                        }
+                    }
+                    None => {
+                        self.config.$name = $value;
+                        log::warn!(
+                            "failed to save config {:?}: no config handler",
+                            stringify!($name)
+                        );
+                    }
+                }
+            };
+        }
+
         match message {
             Message::Todo => {
                 log::warn!("TODO");
             }
             Message::AppTheme(app_theme) => {
-                self.config.app_theme = app_theme;
+                config_set!(app_theme, app_theme);
-                return self.save_config();
+                return self.update_config();
             }
             Message::Config(config) => {
                 if config != self.config {