feat: check for matcha availability

We want to check if matcha will be available both as a binary and as a
daemon, as it needs to be running in the background. If those are not
met, the idle inhibitor cannot be shown.

app.ts

@@ -1,6 +1,6 @@
 import { App } from "astal/gtk4";
 import style from "./style.scss";
-import Bar from "./widget/Bar";
+import Bar from "@/widget/Bar";
 
 App.start({
     css: style,

flake.nix

@@ -31,6 +31,8 @@
       network
       tray
       wireplumber
+      pkgs.brightnessctl
+      matcha.packages.${pkgs.system}.default
     ];
   in {
     packages.${system} = {

src/lib/utils.ts

@@ -0,0 +1,19 @@
+import { execAsync } from "astal";
+
+// https://github.com/andre-brandao/hyprshell/blob/bb26e6a1f9afa924b3bb4acfbf822e8fed37221e/src/lib/utils.ts
+/**
+ * @returns true if all of the `bins` are found
+ */
+export function dependencies(...bins: string[]) {
+    const missing = bins.filter((bin) => {
+        execAsync(`which ${bin}`)
+            .then(() => true)
+            .catch(() => false);
+    });
+
+    if (missing.length > 0) {
+        console.warn(Error(`missing dependencies: ${missing.join(", ")}`));
+    }
+
+    return missing.length === 0;
+}

src/widget/Bar.tsx

@@ -1,11 +1,12 @@
 import { Astal, Gtk, Gdk } from "astal/gtk4";
-import { Variable, GLib, bind, execAsync, exec } from "astal";
+import { Variable, GLib, bind, exec } from "astal";
 import Battery from "gi://AstalBattery";
 import Bluetooth from "gi://AstalBluetooth";
 import Wp from "gi://AstalWp";
 import Network from "gi://AstalNetwork";
 import Hyprland from "gi://AstalHyprland";
-import Brightness from "../service/brightness";
+import Brightness from "@/service/brightness";
+import { dependencies } from "@/lib/utils";
 
 const network = Network.get_default();
 const wifi = bind(network, "wifi");
@@ -102,25 +103,41 @@ function Time({ format = "%H:%M - %A %e." }) {
   );
 }
 
-function IdleInhibitor() {
-  const icon = Variable(getIcon());
+type IdleState = "active" | "inactive" | "unknown";
 
-  function getIcon() {
-    const state = exec("matcha --status");
-    const enabled = state.match(/on/g);
-    return enabled ? "my-caffeine-on-symbolic" : "my-caffeine-off-symbolic";
+function IdleInhibitor() {
+  /*
+   * matcha needs additional checking to ensure the daemon is properly running
+   */
+  function isDaemonRunning() {
+    try {
+      exec("matcha --status");
+      return true;
+    } catch {
+      return false;
     }
+  }
+
+  if (!dependencies("matcha") || !isDaemonRunning()) return <></>;
+
+  const state = Variable<IdleState>("unknown");
 
   function toggle() {
     exec("matcha --toggle");
-    icon.set(getIcon());
+    const response = exec("matcha --status");
+    const enabled = response.match(/on/g);
+    state.set(enabled ? "active" : "inactive");
   }
 
   return (
     <box cssName="IdleInhibitor">
       <button
         onClicked={() => toggle()}
-        iconName={bind(icon).as((iconName) => iconName)}
+        iconName={bind(state).as((s) =>
+          s === "active"
+            ? "my-caffeine-on-symbolic"
+            : "my-caffeine-off-symbolic",
+        )}
       />
     </box>
   );

tsconfig.json

@@ -7,6 +7,10 @@
     "module": "ES2022",
     "moduleResolution": "Bundler",
     "strict": true,
-        "target": "ES2022"
+    "target": "ES2022",
+    "paths": {
+      "@": ["./src"],
+      "@/*": ["./src/*"]
+    }
   }
 }