Prevent device from sleeping while media is playing

I was testing the entire time on net power, so I forgot that the device
goes to sleep after a while.

qml/harbour-sailfin.qml

@@ -21,7 +21,9 @@ import QtQuick 2.0
 import Sailfish.Silica 1.0
 import QtMultimedia 5.6
 import nl.netsoj.chris.Jellyfin 1.0
+
 import Nemo.Notifications 1.0
+import Nemo.KeepAlive 1.2
 
 import "components"
 import "pages"
@@ -52,11 +54,6 @@ ApplicationWindow {
         }
     }
 
-    MediaPlayer {
-        id: _mediaPlayer
-        autoPlay: true
-    }
-
     initialPage: Component {
         MainPage {
             Connections {
@@ -95,4 +92,19 @@ ApplicationWindow {
             publish();
         }
     }
+
+    MediaPlayer {
+        id: _mediaPlayer
+        autoPlay: true
+    }
+
+    // Keep the sytem alive while playing media
+    KeepAlive {
+        enabled: _mediaPlayer.playbackState == MediaPlayer.PlayingState
+    }
+
+    DisplayBlanking {
+        preventBlanking: _mediaPlayer.playbackState == MediaPlayer.PlayingState && _mediaPlayer.hasVideo
+    }
+
 }