;;; org-roam-reflinks.el --- The reflinks section -*- lexical-binding: t -*-
;; Copyright © 2020 Jethro Kuan <jethrokuan95@gmail.com>

;; Author: Jethro Kuan <jethrokuan95@gmail.com>
;; URL: https://github.com/org-roam/org-roam
;; Keywords: org-mode, roam, convenience
;; Version: 2.0.0
;; Package-Requires: ((emacs "26.1") (dash "2.13") (f "0.17.2") (s "1.12.0") (org "9.4") (emacsql "3.0.0") (emacsql-sqlite3 "1.0.2") (magit-section "2.90.1"))


;; This file is NOT part of GNU Emacs.

;; This program is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 3, or (at your option)
;; any later version.
;;
;; This program is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.

;;; Commentary:
;;
;; This library provides functionality dealing with nodes.
;;
;;; Code:
;;;; Library Requires
(require 'magit-section)
(require 'org-roam-structs)

(defvar org-roam-mode-sections)
(defvar org-roam-mode-map)

;;; Section
;;;; Definition

;;; Functions
(cl-defmethod org-roam-populate ((reflink org-roam-reflink))
  "Populate REFLINK from database."
  (setf (org-roam-reflink-source-node reflink)
        (org-roam-populate (org-roam-reflink-source-node reflink)))
  reflink)

(defun org-roam-reflinks-get (node)
  "Return the reflinks for NODE."
  (let ((refs (org-roam-db-query [:select [ref] :from refs
                                  :where (= node-id $s1)]
                                 (org-roam-node-id node)))
        links)
    (pcase-dolist (`(,ref) refs)
      (pcase-dolist (`(,source-id ,pos ,properties) (org-roam-db-query
                                                     [:select [source pos properties]
                                                      :from links
                                                      :where (= dest $s1)]
                                                     ref))
        (push (org-roam-populate
               (org-roam-reflink-create
                :source-node (org-roam-node-create :id source-id)
                :ref ref
                :point pos
                :properties properties)) links)))
    links))

(defun org-roam-reflinks-sort (a b)
  "Default sorting function for reflinks A and B.
Sorts by title."
  (string< (org-roam-node-title (org-roam-reflink-source-node a))
           (org-roam-node-title (org-roam-reflink-source-node b))))

;;; Section inserter
(cl-defun org-roam-reflinks-insert-section (&key node _file)
  "Insert reflinks section for NODE."
  (when (org-roam-node-refs node)
    (let* ((reflinks (seq-sort #'org-roam-reflinks-sort (org-roam-reflinks-get node))))
      (magit-insert-section (org-roam-reflinks)
        (magit-insert-heading "Reflinks:")
        (dolist (reflink reflinks)
          (org-roam-node-insert-section
           :source-node (org-roam-reflink-source-node reflink)
           :point (org-roam-reflink-point reflink)
           :properties (org-roam-reflink-properties reflink)))
        (insert ?\n)))))

(provide 'org-roam-reflinks)
;;; org-roam-reflinks.el ends here