Implemented a callable function that sets the wallpaper. (#463)

* Implemented a callable function that sets the wallpaper.

* Remove log

globals.d.ts

@@ -8,6 +8,7 @@ declare global {
     var getSystrayItems: () => string;
     var isWindowVisible: (windowName: string) => boolean;
     var clearAllNotifications: () => Promise<void>;
+    var setWallpaper: (filePath: string) => void;
 
     var globalWeatherVar: VariableType<Weather>;
     var options: Options;

globals/wallpaper.ts

@@ -0,0 +1,22 @@
+import GLib from 'gi://GLib?version=2.0';
+import { Notify } from 'lib/utils';
+import options from 'options';
+import Wallpaper from 'services/Wallpaper';
+
+const { EXISTS, IS_REGULAR } = GLib.FileTest;
+const { enable: enableWallpaper, image } = options.wallpaper;
+
+globalThis.setWallpaper = (filePath: string): void => {
+    if (!(GLib.file_test(filePath, EXISTS) && GLib.file_test(filePath, IS_REGULAR))) {
+        Notify({
+            summary: 'Failed to set Wallpaper',
+            body: 'The input file is not a valid wallpaper.',
+        });
+    }
+
+    image.value = filePath;
+
+    if (enableWallpaper.value) {
+        Wallpaper.set(filePath);
+    }
+};

main.ts

@@ -1,6 +1,7 @@
 import 'lib/session';
 import 'scss/style';
 import 'globals/useTheme';
+import 'globals/wallpaper';
 import 'globals/systray';
 import 'globals/dropdown.js';
 import 'globals/utilities';