#|
> (comprehend-directory #p"recordings/*.*")
(((NAMESTRING . "9021-1680324909_855162500-call_4036.m4a")
  (DECODED-TIME (YEA . 2023) (MON . 3) (DAY . 31) (HOU . 23) (MIN . 55)
   (SEC . 9))
  (TGID . 9021) (UNIX-TIME . 1680324909) (LOCATION? . 855162500)
  (UNUSED . CALL) (INDEX . 4036)))

This solves filtering in lisp using association list tools.

Common Lisp has its own wildcard stuff #p"foo/*.*"
|#

(defun do-nothing (s c) "
Placed in tmp *readtable* for #\- and #\_
" (declare (ignore c))
 (read s t nil t))

(defmacro decode-unix-time (time &aux (fields
                             '(sec min hou day month yea))) "
(decode-universal-time (+ time 2208970800))
2208970800 seconds seem to be the difference.  
Off by one hour since I made this in daylight savings time."
 `(multiple-value-bind ,fields
   (decode-universal-time (+ ,time 2208970800))
   (pairlis '(,@fields)
     ,(append '(list) fields))))

(defmacro comprehend-path-name (name) "
(comprehend-namestring name)
name is actually the string from (pathname-name path) "
 `(let ((*readtable* (copy-readtable nil)))
   (set-macro-character #\- #'do-nothing)
   (set-macro-character #\_ #'do-nothing)
   (with-input-from-string (in ,name)
    (loop for no = (handler-case (read in nil nil) (end-of-file (e) nil))
     for field in '(tgid unix-time location? unused index)
     while no collect `(,field . ,no)))))

(defun comprehend-directory (dir &aux (files (directory dir)))
 (loop for file in files
  for namestring = (file-namestring file)
  for path-name = (pathname-name file)
  for alist = (comprehend-path-name path-name)
  for time = (decode-unix-time
              (cdr (assoc 'unix-time alist)))
  collect (append `((namestring . ,namestring)
            (decoded-time . ,time))
         alist)))

(defmacro assoc-filter-dir (dir &rest sexps)
 (let ((x (gensym)) (time (gensym))
       (time-symbols '(sec min month hou day yea)))
 `(mapcan (lambda (,x) (and ,@(loop for sexp in sexps 
       for modified = (list (cadr sexp)
                       `(cdr (assoc ',(first sexp)
                              ,(if (member (first sexp) time-symbols)
                                 `(cdr (assoc 'decoded-time ,x)) x)))
                        (third sexp))
      collect modified) (list ,x)))
   (comprehend-directory ,dir))))