Replaced set-lockscreen by the new version of set-wallpaper (modified), and many more but not that significant changes

.local/bin/set-lockscreen

@@ -1,22 +1,50 @@
 #!/bin/sh
 
+# Actually just a modified version of the set-wallpaper script, explaining some potential inconsistencies in variables naming or whatever else.
+
+print_help() {
+    echo "Usage: $0 [input-file]"
+    echo
+    echo "Changes your current lockscreen wallpaper"
+    echo "Please note that this script is made to be used with the Atlas Desktop and will probably not work on most other desktops."
+}
+
+if [ $# -ne 1 ]; then
+    print_help
+    exit 1
+fi
+
 # Check if file exists
-if [ -e $1 ]; then
+if [ -e "$1" ]; then
 
     # Variables declaration
     wallpaper_config=~/.config/hypr/hyprlock.conf
     wallpaper_path=~/.config/hypr/images/lockscreen # Doesn't contain file extension
     file_extension="${1##*.}"
 
+    # In case file has no extension
+    if [ "${file_extension}" == "$1" ]; then
+        echo "Error: please provide a file extension (ex: .jpg, .png...)"
+        exit 1
+    fi
+
     # Remove old wallpaper
     rm $wallpaper_path*
 
     # Copy file
-    cp $1 "${wallpaper_path}.${file_extension}"
+    cp "$1" "${wallpaper_path}.${file_extension}"
+    if [ $? != 0 ]; then
+        echo "Aborted."
+        exit 1
+    fi
     
     # Update config
     sed -i "s/lockscreen\.[^[:space:]]*/lockscreen.$file_extension/g" $wallpaper_config # Replace current extension by new extension
-    
+    if [ $? != 0 ]; then
+        echo "Aborted."
+        exit 1
+    fi
+
     echo "Done"
     exit 0
 else