feat: theme management (#46)

app/src/app.rs

@@ -7,7 +7,8 @@ use cosmic_panel_config::CosmicPanelConfig;
 use cosmic_settings_page::{self as page, section};
 
 use cosmic::{
-    cosmic_config::config_subscription,
+    cosmic_config::{config_subscription, CosmicConfigEntry},
+    cosmic_theme::util::CssColor,
     iced::{
         self,
         event::wayland::{self, WindowEvent, WindowState},
@@ -28,6 +29,7 @@ use cosmic::{
     },
     Element, ElementExt,
 };
+use tracing::error;
 
 use crate::{
     config::Config,
@@ -45,7 +47,7 @@ use crate::{
     widget::{page_title, parent_page_button, search_header, sub_page_button},
 };
 
-use std::{borrow::Cow, process};
+use std::{borrow::Cow, process, sync::Arc};
 
 #[allow(clippy::struct_excessive_bools)]
 #[allow(clippy::module_name_repetitions)]
@@ -88,6 +90,7 @@ pub enum Message {
     WindowState(WindowState),
     PanelConfig(CosmicPanelConfig),
     DesktopInfo,
+    ThemeChanged(Theme),
 }
 
 impl Application for SettingsApp {
@@ -116,8 +119,8 @@ impl Application for SettingsApp {
             search_selections: Vec::default(),
             show_maximize: true,
             show_minimize: true,
-            theme: Theme::dark(),
             window_width: 0,
+            theme: theme(),
         };
 
         // app.insert_page::<wifi::Page>();
@@ -199,6 +202,23 @@ impl Application for SettingsApp {
                     }
                 },
             ),
+            config_subscription::<u64, cosmic::cosmic_theme::Theme<CssColor>>(
+                0,
+                cosmic::cosmic_theme::NAME.into(),
+                cosmic::cosmic_theme::Theme::<CssColor>::version() as u64,
+            )
+            .map(|(_, res)| {
+                let theme = res.map_or_else(
+                    |(errors, theme)| {
+                        for err in errors {
+                            error!("{:?}", err);
+                        }
+                        theme.into_srgba()
+                    },
+                    cosmic::cosmic_theme::Theme::into_srgba,
+                );
+                Message::ThemeChanged(cosmic::theme::Theme::custom(Arc::new(theme)))
+            }),
         ])
     }
 
@@ -313,6 +333,9 @@ impl Application for SettingsApp {
                     ));
                 }
             }
+            Message::ThemeChanged(theme) => {
+                self.theme = theme;
+            }
         }
         ret
     }
@@ -602,3 +625,22 @@ impl SettingsApp {
             .map(Message::Page)
     }
 }
+
+fn theme() -> Theme {
+    let Ok(helper) = cosmic::cosmic_config::Config::new(
+        cosmic::cosmic_theme::NAME,
+        cosmic::cosmic_theme::Theme::<CssColor>::version() as u64,
+    ) else {
+        return cosmic::theme::Theme::dark();
+    };
+    let t = cosmic::cosmic_theme::Theme::get_entry(&helper).map_or_else(
+        |(errors, theme)| {
+            for err in errors {
+                tracing::error!("{:?}", err);
+            }
+            theme.into_srgba()
+        },
+        cosmic::cosmic_theme::Theme::into_srgba,
+    );
+    cosmic::theme::Theme::custom(Arc::new(t))
+}