From 0aab3875c96167234ef00487119116ef69c9ab21 Mon Sep 17 00:00:00 2001
From: Gerard Vermeulen <gerard.vermeulen@posteo.net>
Date: Thu, 22 Jun 2023 17:34:55 +0200
Subject: [PATCH] Work on introspection for better `org-columns' support

---
 README.org | 85 +++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 81 insertions(+), 4 deletions(-)

diff --git a/README.org b/README.org
index 15ad2de..9d9ada9 100644
--- a/README.org
+++ b/README.org
@@ -2172,7 +2172,8 @@ list detailing and motivating each listing:
                  ol-info
                  org-id
                  org-protocol
-                 org-tempo)))
+                 org-tempo)
+   org-use-property-inheritance t))
 #+end_src
 
 #+caption[Setup =org-babel=]:
@@ -2716,14 +2717,13 @@ Set ~org-html-style-default~ option to add =HTML+CSS+JS= for ~mhtml-mode~:
 *** Org introspection
 :PROPERTIES:
 :CUSTOM_ID: sec:org-introspection
-:header-args:emacs-lisp: :exports code :tangle no
 :END:
 
 #+caption[Find valid entries for =org-babel-load-languages=]:
 #+caption: Find valid entries for =org-babel-load-languages=.
 #+name: lst:valid-org-babel-load-languages-entries
 #+header: :wrap "src emacs-lisp :results silent :tangle no"
-#+begin_src emacs-lisp :exports both :results value pp
+#+begin_src emacs-lisp :exports both :results value pp :tangle no
 (defun all-org-babel-execute-fns ()
   "Find `ob-LANGUAGE' files in Org defining `org-babel-execute:LANGUAGE'.
 
@@ -2803,7 +2803,7 @@ Return a list of items where the filename is the `car' of each item and the
 #+caption: Find active Org Babel languages.
 #+name: lst:org-babel-active-languages
 #+header: :wrap "src emacs-lisp :results silent :tangle no"
-#+begin_src emacs-lisp :exports both :results value pp
+#+begin_src emacs-lisp :exports both :results value pp :tangle no
 (defun org-babel-active-languages ()
   (let ((result '("conf" "text" "toml")))
     (mapatoms
@@ -2851,6 +2851,83 @@ Return a list of items where the filename is the `car' of each item and the
  ("toml"))
 #+end_src
 
+#+caption[Jump to an Org =headline=]:
+#+caption: Jump to an Org =headline=. A ~mapcan~ filter works on the
+#+caption: result of ~cl-loop~ and ~collect~ to return a list containing
+#+caption: the position and text of all matching headlines.
+#+name: lst:jump-org-headline
+#+begin_src emacs-lisp :results silent
+(with-eval-after-load 'org-element
+  (defun jump-org-headline (target)
+    "Jump to the first org-mode headline matching TARGET."
+    (interactive "sTarget: ")
+    (if (derived-mode-p 'org-mode)
+        (when-let
+            ((ok (mapcan
+                  (lambda (x) (when (car x) (cdr x)))
+                  (cl-loop
+                   for (here . text)
+                   in (org-element-map (org-element-parse-buffer) 'headline
+                        (lambda (hl)
+                          (cons (org-element-property :begin hl)
+                                (org-element-property :raw-value hl))))
+                   collect (list (string= target text) here text))))
+             (n (/ (length ok) 2)))
+          (goto-char (car ok))
+          (when (> n 1)
+            (user-error "Found %s headlines `%s'" n target)))
+      (message "Found no `%s' headline (`%s')" target major-mode))))
+#+end_src
+
+#+caption[Sync the "#+COLUMNS:" keyword with a ":COLUMNS:" property]:
+#+caption: Sync the "#+COLUMNS:" keyword with a ":COLUMNS:" property.
+#+name: lst:sync-columns-keyword-with-property
+#+begin_src emacs-lisp :results silent
+(with-eval-after-load 'org
+  (defun get-org-columns-property (target level)
+    "Get headline TARGET \":COLUMNS:\" property at LEVEL."
+    (let (case-fold-search done (here (point)))
+      (goto-char (point-max))
+      (while (re-search-backward org-complex-heading-regexp nil t)
+        (let ((beginning (match-beginning 1))
+              (headline (match-string-no-properties 4)))
+	  (when (and (string= headline target)
+                     (= (org-current-level) level))
+            (goto-char beginning)))
+        (setq done (plist-get (org-element--get-node-properties) ':COLUMNS)))
+      (goto-char here)
+      done))
+
+  (defun get-org-columns-keyword-match ()
+    "Get \"#+COLUMNS:\" keyword match data for replacement."
+    (org-with-wide-buffer
+     (goto-char (point-min))
+     (let ((case-fold-search t) done
+           (regexp "\\(^[ \t]*#\\+COLUMNS: \\)\\(.+\\)$"))
+       (while (and (not done) (re-search-forward regexp nil t 1))
+         (when (eq (org-element-type (org-element-at-point)) 'keyword)
+           (setq done (list (regexp-quote (match-string 2))
+                            (match-beginning 2) (match-end 2)))))
+       done)))
+
+  (defun sync-org-columns-keyword-property (target level)
+    "Sync \"#+COLUMNS:\" keyword with \":COLUMNS:\" property.
+The property is from the drawer of headline matching TARGET and LEVEL."
+    (when-let ((property (get-org-columns-property target level))
+               (match (get-org-columns-keyword-match)))
+      (org-with-wide-buffer
+       (goto-char (point-min))
+       (let ((case-fold-search t) done
+             (regexp "\\(^[ \t]*#\\+COLUMNS: \\)\\(.+\\)$"))
+         (while (and (not done) (re-search-forward regexp nil t 1))
+           (when (eq (org-element-type (org-element-at-point)) 'keyword)
+             (replace-string
+              (nth 0 match) property nil (nth 1 match) (nth 2 match))
+             (setq done t)))))
+      (unless property (message "Can't find \":COLUMNS:\" property"))
+      (unless match (message "Can't find \"#+COLUMNS:\" keyword")))))
+#+end_src
+
 *** [[https://github.com/bdarcus/citar][Citar: citing bibliography]] with [[https://orgmode.org/][Org Mode]]
 :PROPERTIES:
 :CUSTOM_ID: sec:citing-bibliography