quickshell: match mono icons by name, iconPath returns a URI

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

settings/quickshell.nix

@@ -19,6 +19,33 @@ let
   defaultWall = config.fred.theming.defaultWall;
   themeApply = config.fred.theming.apply;
   monoIcons = config.fred.theming.monoIcons;
+
+  # The set of app icons YAMIS actually ships, as a QML singleton.
+  #
+  # AppIcon needs to know whether a given icon came from the monochrome set
+  # (safe to flatten to one colour) or fell through to Papirus (not — see the
+  # component). It cannot tell from the resolved source: Quickshell.iconPath
+  # returns an "image://icon/<name>" provider URI, never a filesystem path,
+  # so there is no store path or theme directory in it to match on. The name
+  # is all we get, so the name is what we test.
+  #
+  # Built here rather than listed at eval time: reading the icon tree during
+  # evaluation would mean IFD, and hosts evaluate this straight from the
+  # Forgejo remote.
+  monoIconNames = pkgs.runCommand "MonoIcons.qml" { } ''
+    {
+      echo "pragma Singleton"
+      echo "import QtQuick"
+      echo "QtObject {"
+      printf '  readonly property var names: ['
+      for f in ${monoIcons}/apps/16/*.svg ${monoIcons}/apps/scalable/*.svg; do
+        [ -e "$f" ] || continue
+        basename "$f" .svg
+      done | sort -u | while read -r n; do printf '"%s",' "$n"; done
+      printf ']\n'
+      echo "}"
+    } > $out
+  '';
 in
 {
   config = lib.mkIf (lib.elem config.networking.hostName [ "FredOS-Gaming" "FredOS-Macbook" ]) {
@@ -386,11 +413,17 @@ in
           channels = mono
         '';
       in {
+        "quickshell/MonoIcons.qml" = {
+          onChange = qsRestart;
+          source = monoIconNames;
+        };
+
         "quickshell/qmldir" = {
           onChange = qsRestart;
           text = ''
             singleton Theme 1.0 Theme.qml
             singleton Commands 1.0 Commands.qml
+            singleton MonoIcons 1.0 MonoIcons.qml
             Bar 1.0 Bar.qml
             Lock 1.0 Lock.qml
             Cheatsheet 1.0 Cheatsheet.qml
@@ -1318,13 +1351,6 @@ in
                 readonly property string wxFetch: "${wxFetchScript}"
                 readonly property string xdgOpen: "${pkgs.xdg-utils}/bin/xdg-open"
                 readonly property string themeApply: "${themeApply}"
-                // Directory name of the monochrome icon theme. AppIcon tests
-                // a resolved icon path against this to decide whether it may
-                // be tinted — see the component for why that is not blanket.
-                // A name, not the store path: lookups resolve through the
-                // /run/current-system/sw symlink farm, whose paths never
-                // contain the store prefix.
-                readonly property string monoIconDir: "/${baseNameOf monoIcons}/"
             }
           '';
         };
@@ -1764,8 +1790,17 @@ in
                     id: _ai
                     property string path: ""
                     property int size: 32
-                    readonly property bool mono:
+                    // iconPath hands back "image://icon/<name>", so the name
-                        _ai.path !== "" && _ai.path.indexOf(Commands.monoIconDir) !== -1
+                    // is the only thing to go on — MonoIcons lists what YAMIS
+                    // ships. Anything else (a real file path, a notification
+                    // carrying its own image) is not ours to recolour.
+                    readonly property bool mono: {
+                        if (_ai.path.indexOf("image://icon/") !== 0) return false;
+                        var n = _ai.path.substring(13);
+                        var q = n.indexOf("?");
+                        if (q !== -1) n = n.substring(0, q);
+                        return MonoIcons.names.indexOf(n) !== -1;
+                    }
 
                     width: size
                     height: size