;;; scimax-ob-line-numbers.el --- Description -*- lexical-binding: t; -*-
;;
;; Copyright (C) 2025 Ionut Adrian Ciolan
;;
;; Author: https://github.com/jkitchin/scimax/
;; Maintainer: Ionut Adrian Ciolan <iadrian@ciolan.net>
;; Created: June 29, 2025
;; Modified: June 29, 2025
;; Version: 0.0.1
;; Original code: https://github.com/jkitchin/scimax/blob/master/scimax-ob.el#L301
;; Homepage:
;; Package-Requires: ((emacs "24.3"))
;;
;; This file is not part of GNU Emacs.
;;
;;  Description
;; Add line numbers in org code-blocks
;;; Code:

(require 's)
(require 'org)
(require 'cl-lib)

(defvar scimax-ob-number-line-overlays '()
  "List of overlays for line numbers.")

(make-variable-buffer-local 'scimax-ob-number-line-overlays)

(defun scimax-ob-toggle-line-numbers ()
  "Toggle line numbers in the current Org source block."
  (interactive)
  (if scimax-ob-number-line-overlays
      (scimax-ob-remove-line-numbers)
    (scimax-ob-add-line-numbers)))

(defun scimax-ob-remove-line-numbers ()
  "Remove line numbers from the current Org source block."
  (interactive)
  (mapc #'delete-overlay scimax-ob-number-line-overlays)
  (setq-local scimax-ob-number-line-overlays '())
  (remove-hook 'post-command-hook #'scimax-ob-add-line-numbers t))

(defun scimax-ob-add-line-numbers ()
  "Add line numbers to the current Org source block."
  (interactive)
  (save-excursion
    (let* ((src-block (org-element-context))
           (nlines (- (length (s-split "\n" (org-element-property :value src-block))) 1)))
      (scimax-ob-remove-line-numbers)
      (goto-char (org-element-property :begin src-block))
      (while (not (looking-at "#\\+BEGIN"))
        (forward-line))
      (forward-line)
      (cl-loop for i from 1 to nlines do
               (beginning-of-line)
               (let ((ov (make-overlay (point) (point))))
                 (overlay-put ov 'before-string
                              (propertize (format "%03s " i)
                                          'font-lock-face '(:foreground "fg-main" :background "bg-main")))
                 (push ov scimax-ob-number-line-overlays))
               (forward-line))))
  (add-hook 'post-command-hook #'scimax-ob-add-line-numbers nil 'local))

(provide 'scimax-ob-line-numbers)
;;; scimax-ob-line-numbers.el ends here