paths: use unified env var for lib dir

CAELESTIA_BD_PATH -> CAELESTIA_LIB_DIR/beat_detector

flake.nix

@@ -49,8 +49,7 @@
         pkgs.mkShellNoCC {
           inputsFrom = [shell];
           packages = with pkgs; [material-symbols rubik nerd-fonts.caskaydia-cove];
-          CAELESTIA_BD_PATH = "${shell}/bin/beat_detector";
-          CAELESTIA_II_PATH = "${shell}/bin/inhibit_idle";
+          CAELESTIA_LIB_DIR = "${shell}/lib";
         };
     });
 

nix/default.nix

@@ -94,7 +94,7 @@ in
       makeWrapper ${quickshell}/bin/qs $out/bin/caelestia-shell \
       	--prefix PATH : "${lib.makeBinPath runtimeDeps}" \
       	--set FONTCONFIG_FILE "${fontconfig}" \
-      	--set CAELESTIA_BD_PATH $out/lib/beat_detector \
+      	--set CAELESTIA_LIB_DIR $out/lib/beat_detector \
         --set CAELESTIA_XKB_RULES_PATH ${xkeyboard-config}/share/xkeyboard-config-2/rules/base.lst \
       	--add-flags "-p $out/share/caelestia-shell"
     '';

services/BeatDetector.qml

@@ -1,5 +1,6 @@
 pragma Singleton
 
+import qs.utils
 import Quickshell
 import Quickshell.Io
 
@@ -10,7 +11,7 @@ Singleton {
 
     Process {
         running: true
-        command: [Quickshell.env("CAELESTIA_BD_PATH") || "/usr/lib/caelestia/beat_detector", "--no-log", "--no-stats", "--no-visual"]
+        command: [`${Paths.libdir}/beat_detector`, "--no-log", "--no-stats", "--no-visual"]
         stdout: SplitParser {
             onRead: data => {
                 const match = data.match(/BPM: ([0-9]+\.[0-9])/);

utils/Paths.qml

@@ -15,6 +15,7 @@ Singleton {
     readonly property url config: `${StandardPaths.standardLocations(StandardPaths.GenericConfigLocation)[0]}/caelestia`
 
     readonly property url imagecache: `${cache}/imagecache`
+    readonly property string libdir: Quickshell.env("CAELESTIA_LIB_DIR") || "/usr/lib/caelestia"
 
     function stringify(path: url): string {
         let str = path.toString();