From e9aeb9ac6063494d028c2254f4b98369d8f06879 Mon Sep 17 00:00:00 2001
From: bbedward <bbedward@gmail.com>
Date: Mon, 30 Mar 2026 15:18:44 -0400
Subject: [PATCH] blur: add probe to check compositor for ext-bg-effect

---
 core/cmd/dms/commands_blur.go       | 40 +++++++++++++++++++++++++++++
 core/cmd/dms/commands_common.go     |  1 +
 core/internal/blur/probe.go         | 35 +++++++++++++++++++++++++
 quickshell/Services/BlurService.qml | 31 +++++++++++++++++++---
 4 files changed, 104 insertions(+), 3 deletions(-)
 create mode 100644 core/cmd/dms/commands_blur.go
 create mode 100644 core/internal/blur/probe.go

diff --git a/core/cmd/dms/commands_blur.go b/core/cmd/dms/commands_blur.go
new file mode 100644
index 00000000..d01eb932
--- /dev/null
+++ b/core/cmd/dms/commands_blur.go
@@ -0,0 +1,40 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/AvengeMedia/DankMaterialShell/core/internal/blur"
+	"github.com/spf13/cobra"
+)
+
+var blurCmd = &cobra.Command{
+	Use:   "blur",
+	Short: "Background blur utilities",
+}
+
+var blurCheckCmd = &cobra.Command{
+	Use:   "check",
+	Short: "Check if the compositor supports background blur (ext-background-effect-v1)",
+	Args:  cobra.NoArgs,
+	Run:   runBlurCheck,
+}
+
+func init() {
+	blurCmd.AddCommand(blurCheckCmd)
+}
+
+func runBlurCheck(cmd *cobra.Command, args []string) {
+	supported, err := blur.ProbeSupport()
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Error: %v\n", err)
+		os.Exit(1)
+	}
+
+	switch supported {
+	case true:
+		fmt.Println("supported")
+	default:
+		fmt.Println("unsupported")
+	}
+}
diff --git a/core/cmd/dms/commands_common.go b/core/cmd/dms/commands_common.go
index cfb087fa..6557860d 100644
--- a/core/cmd/dms/commands_common.go
+++ b/core/cmd/dms/commands_common.go
@@ -525,5 +525,6 @@ func getCommonCommands() []*cobra.Command {
 		configCmd,
 		dlCmd,
 		randrCmd,
+		blurCmd,
 	}
 }
diff --git a/core/internal/blur/probe.go b/core/internal/blur/probe.go
new file mode 100644
index 00000000..e9c24b8c
--- /dev/null
+++ b/core/internal/blur/probe.go
@@ -0,0 +1,35 @@
+package blur
+
+import (
+	wlhelpers "github.com/AvengeMedia/DankMaterialShell/core/internal/wayland/client"
+	client "github.com/AvengeMedia/DankMaterialShell/core/pkg/go-wayland/wayland/client"
+)
+
+const extBackgroundEffectInterface = "ext_background_effect_manager_v1"
+
+func ProbeSupport() (bool, error) {
+	display, err := client.Connect("")
+	if err != nil {
+		return false, err
+	}
+	defer display.Context().Close()
+
+	registry, err := display.GetRegistry()
+	if err != nil {
+		return false, err
+	}
+
+	found := false
+	registry.SetGlobalHandler(func(e client.RegistryGlobalEvent) {
+		switch e.Interface {
+		case extBackgroundEffectInterface:
+			found = true
+		}
+	})
+
+	if err := wlhelpers.Roundtrip(display, display.Context()); err != nil {
+		return false, err
+	}
+
+	return found, nil
+}
diff --git a/quickshell/Services/BlurService.qml b/quickshell/Services/BlurService.qml
index 535d8d6b..40a3aeb8 100644
--- a/quickshell/Services/BlurService.qml
+++ b/quickshell/Services/BlurService.qml
@@ -3,13 +3,16 @@ pragma ComponentBehavior: Bound
 
 import QtQuick
 import Quickshell
+import Quickshell.Io
 import Quickshell.Wayland // ! Import is needed despite what qmlls says
 import qs.Common
 
 Singleton {
     id: root
 
-    property bool available: false
+    property bool quickshellSupported: false
+    property bool compositorSupported: false
+    property bool available: quickshellSupported && compositorSupported
     readonly property bool enabled: available && (SettingsData.blurEnabled ?? false)
 
     readonly property color borderColor: {
@@ -72,6 +75,27 @@ Singleton {
         region.destroy();
     }
 
+    Process {
+        id: blurProbe
+        running: false
+        command: ["dms", "blur", "check"]
+
+        stdout: StdioCollector {
+            onStreamFinished: {
+                root.compositorSupported = text.trim() === "supported";
+                if (root.compositorSupported)
+                    console.info("BlurService: Compositor supports ext-background-effect-v1");
+                else
+                    console.info("BlurService: Compositor does not support ext-background-effect-v1");
+            }
+        }
+
+        onExited: exitCode => {
+            if (exitCode !== 0)
+                console.warn("BlurService: blur probe failed with code:", exitCode);
+        }
+    }
+
     Component.onCompleted: {
         try {
             const test = Qt.createQmlObject(`
@@ -79,8 +103,9 @@ Singleton {
                 Region { radius: 0 }
             `, root, "BlurAvailabilityTest");
             test.destroy();
-            available = true;
-            console.info("BlurService: Initialized with blur support");
+            quickshellSupported = true;
+            console.info("BlurService: Quickshell blur support available");
+            blurProbe.running = true;
         } catch (e) {
             console.info("BlurService: BackgroundEffect not available - blur disabled. Requires a newer version of Quickshell.");
         }