(require :uiop)
(load (sb-ext:posix-getenv "ASDF"))
(asdf:load-system 'str)

(defun get-range (range)
  (let ((range (str:split "-" range)))
    (loop for i from (parse-integer (car range)) to (parse-integer (car (cdr range))) collect i)))
(get-range "11-22")

(defun get-ranges (instr)
  (loop for range in
        (str:split "," (string-trim '(#\Newline) instr))
        collect
        (get-range range)))
(get-ranges "1-3,4-5")

(defun match-sequence (seq-len seq remaining)
  (setq rem-len (length remaining))
  (cond
    ((not (integerp (/ rem-len seq-len))) nil)
    ((string= seq remaining) t)
    ((not (string= seq (subseq remaining 0 seq-len))) nil)
    (t (match-sequence seq-len seq (subseq remaining seq-len)))))
(match-sequence 2 "12" "2212")
(match-sequence 2 "12" "121")
(match-sequence 2 "12" "1212")
(match-sequence 2 "12" "12")

(defun validate-product-id (product-id)
  (setq product-id (format nil "~A" product-id))
  (not
    (loop for seq-len from 1 to (floor (/ (length product-id) 2))
      when (match-sequence seq-len (subseq product-id 0 seq-len) (subseq product-id seq-len))
      do (+ 1 2); not sure how to remove this?
      and return t)))
(validate-product-id 1212)
(validate-product-id 121212)
(validate-product-id 123)
(validate-product-id 1234)

(defun sum-all-invalid-ids (text)
  (reduce #'+
    (remove-if #'validate-product-id
      (reduce #'append
        (get-ranges text)))))

(sum-all-invalid-ids (uiop:read-file-string "02example.txt"))
(sum-all-invalid-ids (uiop:read-file-string "02data.txt"))