;; evaluate this to remove all IDs that are neither: a target, has attachment(s) nor timestamp (synced with caldav)
;; assume everything is in `~/org', including archived files
;; require `rg', `jq' and `awk'
(let* ((default-directory (expand-file-name "~/org"))
       (ids (-> (shell-command-to-string
                 "rg -a -g '*.org*' --json '^:ID:\s*([A-Za-z00-9\-])+\s*$'  | jq -r '.data.submatches | select(.) | .[].match.text' | awk '{ print $2 }' | sort")
                (string-trim)
                (split-string "\n")))
       (targets (-> (shell-command-to-string
                     (format "rg -a -g '*.org*' --json '\\[id:(%s)]' | jq -r '.data.submatches | select(.) | .[].match.text[4:-1]' | sort" (string-join ids "|")))
                    (string-trim)
                    (split-string "\n")))
       (not-targets (seq-difference ids targets)))
  (save-excursion
    (seq-each #'(lambda (id)
                  (condition-case nil
                      (progn
                        (org-id-goto id)
                        (unless (or (org-entry-get nil "SCHEDULED")
                                    (org-entry-get nil "DEADLINE")
                                    (org-entry-get nil "TIMESTAMP")
                                    (member "ATTACH" (org-get-tags nil t)))
                          ;; (message "DELETE %s" id)
                          (org-delete-property "ID")))
                    (error (message "FALSE POSITIVE %s" id))))
              not-targets)))