Use alternative gitea theme

modules/gitea.nix

@@ -1,4 +1,4 @@
-{config, ...}:
+{pkgs, config, ...}:
 {
     services.gitea = {
         enable = true;
@@ -14,6 +14,34 @@
             actions = {
                 ENABLED = false;
             };
+
+            ui = {
+                DEFAULT_THEME = "catppuccin-maroon-auto";
+                THEMES = "catppuccin-maroon-auto,catppuccin-latte-maroon,catppuccin-mocha-maroon";
+            };
         };
     };
+
+    systemd.tmpfiles.rules =
+    let catpuccinThemeSrc =
+    pkgs.fetchzip {
+        url = "https://github.com/catppuccin/gitea/releases/download/v1.0.2/catppuccin-gitea.tar.gz";
+        sha256 = "sha256-rZHLORwLUfIFcB6K9yhrzr+UwdPNQVSadsw6rg8Q7gs=";
+        stripRoot = false;
+    };
+    themeFiles = [
+        "theme-catppuccin-mocha-maroon.css"
+        "theme-catppuccin-latte-maroon.css"
+        "theme-catppuccin-maroon-auto.css"
+    ];
+    customDir = config.services.gitea.customDir;
+    in
+    [
+        "d ${customDir}/public - gitea gitea -"
+        "d ${customDir}/public/assets - gitea gitea -"
+        "d ${customDir}/public/assets/css - gitea gitea -"
+    ]
+    ++ map (f:
+        "L+ ${customDir}/public/assets/css/${f} - - - - ${catpuccinThemeSrc}/${f}"
+    ) themeFiles;
 }