Wallpaper: added IPC to set a wallpaper

qs -c noctalia-shell ipc call wallpaper set $path $monitor

$monitor can be a monitor name or "all" or "" to assign to all monitors.

Modules/IPC/IPCManager.qml

@@ -138,5 +138,12 @@ Item {
         WallpaperService.setRandomWallpaper()
       }
     }
+
+    function set(path: string, screen: string) {
+      if (screen === "all" || screen === "") {
+        screen = undefined
+      }
+      WallpaperService.changeWallpaper(path, screen)
+    }
   }
 }

Modules/SettingsPanel/Tabs/WallpaperSelectorTab.qml

@@ -210,9 +210,9 @@ ColumnLayout {
           hoverEnabled: true
           onPressed: {
             if (Settings.data.wallpaper.setWallpaperOnAllMonitors) {
-              WallpaperService.changeWallpaper(undefined, wallpaperPath)
+              WallpaperService.changeWallpaper(wallpaperPath, undefined)
             } else if (screen) {
-              WallpaperService.changeWallpaper(screen.name, wallpaperPath)
+              WallpaperService.changeWallpaper(wallpaperPath, screen.name)
             }
           }
         }

Services/WallpaperService.qml

@@ -220,7 +220,7 @@ Singleton {
   }
 
   // -------------------------------------------------------------------
-  function changeWallpaper(screenName, path) {
+  function changeWallpaper(path, screenName) {
     if (screenName !== undefined) {
       _setWallpaper(screenName, path)
     } else {
@@ -305,7 +305,7 @@ Singleton {
         if (wallpaperList.length > 0) {
           var randomIndex = Math.floor(Math.random() * wallpaperList.length)
           var randomPath = wallpaperList[randomIndex]
-          changeWallpaper(screenName, randomPath)
+          changeWallpaper(randomPath, screenName)
         }
       }
     } else {
@@ -315,7 +315,7 @@ Singleton {
       if (wallpaperList.length > 0) {
         var randomIndex = Math.floor(Math.random() * wallpaperList.length)
         var randomPath = wallpaperList[randomIndex]
-        changeWallpaper(undefined, randomPath)
+        changeWallpaper(randomPath, undefined)
       }
     }
   }