add format-filename and format-keywords in utils package.

These functions are to help with standardising on the naming formats
when storing files and keywords (for Meilisearch database). The
asciify and slugify functions are not enough. They either leave spaces
in the file names or the file extension gets lost in the standardising
process. Going forward, file names should look like
'this-is-an-example.png' instead of either 'this is an Example.png' or
'this-is-an-example-png'.

src/utils.lisp

@@ -3,7 +3,8 @@
   (:use #:cl
 	#:caveman2
 	#:log4cl
-	#:app-constants)
+	#:app-constants
+	#:storage)
   (:export #:i18n-load
            #:_
            #:parse-iso-date
@@ -19,7 +20,9 @@
 	   #:get-image-dimensions
 	   #:run-bash-command
 	   #:create-thumbnail
-	   #:create-timestamp-id)
+	   #:create-timestamp-id
+	   #:format-filename
+	   #:format-keywords)
   (:documentation "Utilities that do not depend on models."))
 
 (in-package #:utils)
@@ -31,6 +34,19 @@
   "Turns a string of text into a slug."
   (str:downcase (slug:slugify string)))
 
+(defun format-filename (string)
+  "Changes the filename into the system's standard.
+Replaces whitespace with '-' and changes everything to lowecase."
+  (str:replace-all " " "-" (asciify string)))
+
+(defun format-keywords (string)
+  "Formats the keywords used in the `ARCHIVE-ENTRY' class.
+This is mostly just over-prep'ing the keywords assuming the user
+enters them in the incorrect format. Meilisearch exects something like
+'art,welding,green paint,ritherdon'. The comma is the seperator which
+allows each 'keyword' to have (white-)spaces."
+  (str:replace-all ", " "," (asciify string)))
+
 (defun request-params (request)
   (loop :for (key . value) :in request
 	:collect (let ((*package* (find-package :keyword)))
@@ -103,17 +119,19 @@ The `FILEPATH' must be already merged with
 			    :ignore-error-status t
 			    :error-output :string))
 
-(defun create-thumbnail (storage-sub-directory file-name)
+(defun create-thumbnail (storage-sub-directory file-name &optional (overwrite t))
   "Runs a Bash command to convert a file to a thumbnail  in /storage/media dir.
 The file is reduced to 512x512 pixels if bigger than that. A new file
 is then created with a 'thumbnail-' pre-fix. This process relies on
 Image Magick. So, it must be installed on the system for this function
 to operate properly."
   (run-bash-command
-  (format nil "convert ~a -resize 512x512\\> ~a"
-	  (storage:file-exists-p "" storage-sub-directory file-name)
-	  (storage:make-path "" storage-sub-directory
-			     (format nil "thumbnail-~a" file-name)))))
+   (format nil "convert ~a -resize 512x512\\> ~a"
+	   (storage:file-exists-p "" storage-sub-directory file-name)
+	   (if (eq overwrite t)
+	       (storage:file-exists-p "" storage-sub-directory file-name)
+	       (storage:make-path "" storage-sub-directory
+				  (format nil "thumbnail-~a" file-name))))))
 
 (defun create-timestamp-id ()
   "Creates a integer based on time the function is called, in YYYYMMDD format."