Merge pull request #826 from luniiya/feat/theme-favorites

UI: favorite themes and appearance shortcuts

crates/engine/src/prefs.rs

@@ -172,6 +172,8 @@ page!(Appearance {
     dark_theme: String = "dark".into(),
     /// The theme used in light appearance: `light`.
     light_theme: String = "light".into(),
+    /// Theme shortcuts in the appearance context menu.
+    favorite_themes: Vec<String> = Vec::new(),
     /// User interface brightness, -1 (darker) … 1 (lighter).
     brightness: f64 = 0.0,
     /// The size of the whole interface in percent (75–200), on top of the display's own scale.
@@ -564,6 +566,8 @@ impl Prefs {
         a.interval_minutes = a.interval_minutes.clamp(1, 240);
         a.max_versions = a.max_versions.clamp(1, 99);
         let ap = &mut self.appearance;
+        let mut seen = std::collections::BTreeSet::new();
+        ap.favorite_themes.retain(|id| is_choice(THEMES, id) && seen.insert(id.clone()));
         if !is_choice(APPEARANCE_MODES, &ap.appearance_mode) {
             ap.appearance_mode = Appearance::default().appearance_mode;
         }
@@ -620,6 +624,23 @@ impl Prefs {
             let all: Vec<&str> = c.iter().map(|(_, v)| *v).collect();
             return Err(format!("`{key}` expects one of {}", all.join(", ")));
         }
+        let favorites = if key == "appearance.favoriteThemes" {
+            Some(&value)
+        } else if key == "appearance" {
+            value.get("favoriteThemes")
+        } else {
+            None
+        };
+        if let Some(favorites) = favorites {
+            let values = favorites.as_array().ok_or("favorite themes must be a list")?;
+            let mut seen = std::collections::BTreeSet::new();
+            for value in values {
+                let id = value.as_str().ok_or("favorite theme must be a string")?;
+                if !is_choice(THEMES, id) || !seen.insert(id) {
+                    return Err("unknown or duplicate favorite theme".into());
+                }
+            }
+        }
         // Older clients set the single theme (by key, or inside the page object): it still picks
         // a visible theme, fixing the mode to its family.
         let legacy_theme = key == "appearance.theme" || (key == "appearance" && value.get("theme").is_some() && value.get("appearanceMode").is_none());