perf(settings): coalesce refreshes and cache resize previews

shell/ferese-settings/src/visuals.rs

@@ -1,5 +1,7 @@
 use cosmic::Element;
-use cosmic::iced::{Color, Length};
+use cosmic::iced::Color;
+#[cfg(test)]
+use cosmic::iced::Length;
 use cosmic::widget::icon as svg_icon;
 pub use ferese_theme::Palette;
 pub const PAGE_TITLE_SIZE: f32 = 16.;
@@ -109,6 +111,7 @@ pub fn color(value: &str, fallback: Color) -> Color {
     ferese_theme::parse_color(value).unwrap_or(fallback)
 }
 
+#[cfg(test)]
 fn hex(c: Color) -> String {
     format!(
         "#{:02x}{:02x}{:02x}",
@@ -118,10 +121,6 @@ fn hex(c: Color) -> String {
     )
 }
 
-pub fn native_theme(_snapshot: Option<&Snapshot>) -> cosmic::Theme {
-    Palette::from_resolved(&ferese_theme_client::service::current().presented).native_theme()
-}
-
 pub fn icon(page: Page, tint: Color) -> svg_icon::Icon {
     ferese_theme::icons::outline(page.icon(), tint, 19)
 }
@@ -311,11 +310,20 @@ pub fn preview_resolved<'a>(
     snapshot: &Snapshot,
     theme: &ferese_config::theme::ResolvedTheme,
 ) -> Element<'a, Message> {
+    crate::window_preview::view(snapshot, theme)
+}
+
+#[cfg(test)]
+pub(super) fn legacy_preview_resolved(
+    snapshot: &Snapshot,
+    theme: &ferese_config::theme::ResolvedTheme,
+) -> Element<'static, Message> {
     let mut snapshot = snapshot.clone();
     snapshot.doc = snapshot.doc.with_theme(theme);
     preview(&snapshot, theme)
 }
 
+#[cfg(test)]
 fn preview(
     snapshot: &Snapshot,
     theme: &ferese_config::theme::ResolvedTheme,