;; Use ID for storing links
(setq org-link-to-org-use-id t)

;; trigger a capture on done
(add-hook 'org-after-todo-state-change-hook
	  'my-todo-state-change-hook)

;; DONE on a todo item triggers a capture rule "x"
(defun my-todo-state-change-hook () 
  ""
  (when (member state org-done-keywords)
    (org-capture-setup "x")))

;; org-capture-templates

;; Rule-x does this
;; - creates an entry in conversation.org
;; - saves a link to the parent TODO entry in the new conversation node
;; - exits with a call to my-update-todo-node defun

(setq org-capture-templates
      '(("x" "Create conversation node" entry
	 (file+headline "~/conversation.org" "Conversations")
	 "** Conversation-%(int-to-string (random))\n   TODO Context: %a\n   %?"
	 :prepend t :empty-lines 1
	 :exit (my-update-todo-node))))

;;  my-update-todo-node does this
;; - visits the last captured node (ie, the conversation node)
;; - installs a makeshift capture rule and invokes it
;;
;; makeshift capture rule installs a link to the newly created
;; conversation node in the todo node.

(defun my-update-todo-node ()
  (when (not org-note-abort)
    (let (org-capture-templates)

      (with-current-buffer (marker-buffer org-capture-last-stored-marker)
	(save-excursion
	  (goto-char (marker-position org-capture-last-stored-marker))

	  (setq org-capture-templates
		`(("*" "Makeshift" plain
		   (id ,(my-id-from-id-link (org-capture-get :annotation))) 
		   "   %a %U\n   %?")))
	  (org-capture nil "*"))))))


;; this is a library routine used by makeshift capture rule
(defun my-id-from-id-link (id-link)
  ""
  (let (link type path)

    (when (string-match org-bracket-link-regexp id-link)
      (setq link (match-string-no-properties 1  id-link)))

    (when (and link (string-match org-link-re-with-space3 link))
      (setq type (match-string 1 link) path (match-string 2 link)))

    path))

;; (setq hyperlink "[[id:1766a3bb-d717-4779-ac33-98510ada95aa][Conversations]]")