Cubing and Emacs: Checking out the competition

| cubing, emacs

There's an upcoming cubing competition. For the 3x3 event, the top 75% of the first round will get to advance to the second round. I wanted to know what our chances were of making it in. There's an unofficial REST API for the World Cube Association (WCA) results so I don't need to download and unpack megabytes of data.

Here's the basic code I used: 

(let* ((comp-id "COMP-ID-GOES-HERE")
       (url (format "https://www.worldcubeassociation.org/competitions/%s/registrations" comp-id))
       (dom (with-temp-buffer (insert (plz 'get url)) (libxml-parse-html-region)))
       (data-dir (expand-file-name "data" (expand-file-name comp-id "~/proj/cubing/")))
       len
       list)
  (unless (file-directory-p data-dir)
    (make-directory data-dir t))
  (setq list (sort
              (seq-keep
               (lambda (o)
                 (let* ((id (replace-regexp-in-string "/persons/" "" (dom-attr o 'href)))
                        (file (expand-file-name (concat id ".json") data-dir))
                        best)
                   (unless (file-exists-p file)
                     (with-temp-file file
                       (insert
                        (plz 'get (format "https://raw.githubusercontent.com/robiningelbrecht/wca-rest-api/master/api/persons/%s.json" id)))))
                   (let-alist (with-temp-buffer
                                (insert-file-contents file)
                                (json-parse-buffer :object-type 'alist))
                     (setq best
                           (alist-get 'best
                                      (seq-find (lambda (o) (string= (alist-get 'eventId o) "333")) .rank.averages)))
                     (when best
                       (list .id .name (format "%.2f" (/ best 100.0)))))))
               (dom-by-tag (dom-by-id dom "competition-data") 'a))
              (lambda (a b)
                (< (string-to-number (elt a 2)) (string-to-number (elt b 2))))))
  (setq len (length list))
  (seq-map-indexed
   (lambda (o i)
     (cons (format "%d" (/ (* 100.0 i) len))
           o))
   list))

It makes a table with percentile, ID, name, and average time for 3x3. Then I can find out where the 75% mark and see if we can make it in. I think I'll be a bit too slow, but the kiddo might be able to make it to the second round. Could be fun.

Posting here in case someone else might find it handy someday!

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