Refactor detect_desktop_environment()

devices/linux/Files/main.py

@@ -27,6 +27,7 @@
 Contributors:
     Steffen Klemer https://github.com/sklemer1
     ikreb7 https://github.com/ikreb7
+    Yiannis Spanos https://github.com/ispanos
 Many thanks for multiple code fixes, feature ideas, styling remarks
 much of the code provided by them in the form of pull requests
 has been incorporated into the final form of this script.
@@ -107,29 +108,30 @@ def detect_desktop_environment() -> str:
     """
     Detect what desktop type is used. This method is prepared for
     possible future use with password encryption on supported distros
-
-    the function below was partially copied from
-    https://ubuntuforums.org/showthread.php?t=1139057
     """
-    desktop_environment = 'generic'
+    if os.environ.get('XDG_CURRENT_DESKTOP'):
+        return os.environ.get('XDG_CURRENT_DESKTOP').lower()
+
+    # Depreciated method for older distributions
     if os.environ.get('KDE_FULL_SESSION') == 'true':
-        desktop_environment = 'kde'
-    elif os.environ.get('GNOME_DESKTOP_SESSION_ID'):
-        desktop_environment = 'gnome'
-    else:
-        try:
-            shell_command = subprocess.Popen(['xprop', '-root',
-                                              '_DT_SAVE_MODE'],
-                                             stdout=subprocess.PIPE,
-                                             stderr=subprocess.PIPE)
-            out, _ = shell_command.communicate()
-            info = out.decode('utf-8').strip()
-        except (OSError, RuntimeError):
-            pass
-        else:
-            if ' = "xfce4"' in info:
-                desktop_environment = 'xfce'
-    return desktop_environment
+        return 'kde'
+
+    if os.environ.get('GNOME_DESKTOP_SESSION_ID'):
+        return 'gnome'
+
+    try:
+        shell_command = subprocess.Popen(['xprop', '-root',
+                                            '_DT_SAVE_MODE'],
+                                            stdout=subprocess.PIPE,
+                                            stderr=subprocess.PIPE)
+        out, _ = shell_command.communicate()
+        info = out.decode('utf-8').strip()
+    except (OSError, RuntimeError):
+        pass
+    if ' = "xfce4"' in info:
+        return 'xfce'
+
+    return 'generic'
 
 
 def get_system() -> List: