wordle.lisp

(defconstant +words-filename+ "words.txt")

(defun date-to-ms (year month day)
  (* (encode-universal-time 0 0 0 day month year) 1000))

(defvar *base-date* (date-to-ms 2021 6 19))
(defvar *day-in-ms* 86400000)

(defun parse-words-input (pathname)
  (uiop:read-file-lines pathname))

(defun wordle (year month day)
  (let* ((words (parse-words-input +words-filename+))
         (words-length (list-length words))
         (date-diff (floor (- (date-to-ms year month day) *base-date*) *day-in-ms*)))
    (nth (rem date-diff words-length) words)))