Add theme loading

crates/storybook2/src/storybook2.rs

@@ -50,14 +50,7 @@ fn main() {
 
     let story_selector = args.story.clone();
 
-    let theme = match args.theme.as_ref().map(|theme| theme.as_str()) {
-        Some("Rosé Pine") => themes::rose_pine(),
-        Some("Rosé Pine Dawn") => themes::rose_pine_dawn(),
-        Some(theme_name) => {
-            panic!("Only 'Rosé Pine' and 'Rosé Pine Dawn' are currently supported.")
-        }
-        None => themes::rose_pine_dawn(),
-    };
+    let theme = themes::load_theme(args.theme);
 
     let asset_source = Arc::new(Assets);
     gpui3::App::production(asset_source).run(move |cx| {

crates/storybook2/src/themes.rs

@@ -1,3 +1,32 @@
 mod rose_pine;
 
 pub use rose_pine::*;
+
+use gpui3::serde_json;
+use serde::Deserialize;
+use ui::Theme;
+
+use crate::assets::Assets;
+
+#[derive(Deserialize)]
+struct LegacyTheme {
+    pub base_theme: serde_json::Value,
+}
+
+pub fn load_theme(override_theme_name: Option<String>) -> Theme {
+    let theme = if let Some(theme) = override_theme_name {
+        let theme_contents = Assets::get(&format!("themes/{theme}.json"))
+            .unwrap_or_else(|| panic!("failed to load theme: {theme}.json"));
+
+        let legacy_theme: LegacyTheme =
+            serde_json::from_str(std::str::from_utf8(&theme_contents.data).unwrap()).unwrap();
+
+        let new_theme: Theme = serde_json::from_value(legacy_theme.base_theme.clone()).unwrap();
+
+        new_theme
+    } else {
+        rose_pine_dawn()
+    };
+
+    theme
+}