hosts/pi: add snapcast

hosts/pi/snapcast.nix

@@ -0,0 +1,43 @@
+{
+  pkgs,
+  ...
+}:
+
+{
+  # Put all sinks in pipewire group
+  services.pipewire.systemWide = true;
+
+  services.avahi = {
+    enable = true;
+    nssmdns4 = true;
+    publish = {
+      enable = true;
+      domain = true;
+      addresses = true;
+    };
+  };
+
+  services.snapserver = {
+    enable = true;
+    streams = {
+      default = {
+        type = "file";
+        location = "/var/lib/snapserver/test.wav";
+        sampleFormat = "44100:16:2";
+        codec = "flac";
+      };
+    };
+  };
+
+  systemd.services.snapclient = {
+    wantedBy = [ "multi-user.target" ];
+    after = [ "pipewire.service" ];
+    requires = [ "pipewire.service" ];
+    description = "Snapcast client";
+    serviceConfig = {
+      ExecStart = "${pkgs.snapcast}/bin/snapclient -h 127.0.0.1 --player pulse --mixer hardware";
+      DynamicUser = true;
+      SupplementaryGroups = [ "pipewire" ];
+    };
+  };
+}