Show the same name org-files with different identifier given by parent directory name.

org-uniquify-agenda-files.el

(defun ht-org-get-category-string (str-filename)
  (when (string-match "[^/]*/[^/]*\\.[^/]*$" str-filename)
    (progn
      (let ((str (match-string 0 str-filename)))
        (when (string-match "\\.[^/]*$" str)
          (replace-match "" nil nil str)
          )
        )
      )
    )
  )

(defun test-ht-org-get-category-string-match (test-str ans-str)
  (equal ans-str (ht-org-get-category-string test-str))
  )

(test-ht-org-get-category-string-match "~/workspace/org/index.org" "org/index")

(defun org-get-category (&optional pos force-refresh)
  "Get the category applying to position POS."
  (save-match-data
    (when force-refresh (org-refresh-category-properties))
    (let ((pos (or pos (point))))
      ;; (or (get-text-property pos 'org-category)
      ;;     (progn (org-refresh-category-properties)
      ;;            (get-text-property pos 'org-category))
      (or
       (concat (ht-org-get-category-string (buffer-file-name (current-buffer))) "\t")
       (progn (org-refresh-category-properties)
              (concat (ht-org-get-category-string (buffer-file-name (current-buffer))) "\t")
              )))))