(feat): globally restructure and refactor the codebase (#1724)

Detangle the codebase and change how dependencies are resolved to
allow the package to better modularize and load itself without
introducing circular dependencies, especially when autoloads involved.

extensions/org-roam-overlay.el

@@ -0,0 +1,96 @@
+;;; org-roam-overlay.el --- Link overlay for [id:] links to Org-roam nodes -*- coding: utf-8; lexical-binding: t; -*-
+
+;; Copyright © 2020-2021 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") (org "9.4") (org-roam "2.0"))
+
+;; 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 extension provides allows to render [[id:]] links that don't have an
+;; asscoiated descriptor with an overlay that displays the node's current title.
+;;
+;;; Code:
+(require 'org-roam)
+
+(defface org-roam-overlay
+  '((((class color) (background light))
+     :background "grey90" :box (:line-width -1 :color "black"))
+    (((class color) (background dark))
+     :background "grey10" :box (:line-width -1 :color "white")))
+  "Face for the Org-roam overlay."
+  :group 'org-roam-faces)
+
+(defun org-roam-overlay--make (l r &rest props)
+  "Make an overlay from L to R with PROPS."
+  (let ((o (make-overlay l (or r l))))
+    (overlay-put o 'category 'org-roam)
+    (while props (overlay-put o (pop props) (pop props)))
+    o))
+
+(defun org-roam-overlay-make-link-overlay (link)
+  "Create overlay for LINK."
+  (save-excursion
+    (save-match-data
+      (let* ((type (org-element-property :type link))
+             (id (org-element-property :path link))
+             (pos (org-element-property :end link))
+             (desc-p (org-element-property :contents-begin link))
+             node)
+        (when (and (string-equal type "id")
+                   (setq node (org-roam-node-from-id id))
+                   (not desc-p))
+          (org-roam-overlay--make
+           pos pos
+           'after-string (format "%s "
+                                 (propertize (org-roam-node-title node)
+                                             'face 'org-roam-overlay))))))))
+
+(defun org-roam-overlay-enable ()
+  "Enable Org-roam overlays."
+  (org-roam-db-map-links
+   (list #'org-roam-overlay-make-link-overlay)))
+
+(defun org-roam-overlay-disable ()
+  "Disable Org-roam overlays."
+  (remove-overlays nil nil 'category 'org-roam))
+
+(defun org-roam-overlay-redisplay ()
+  "Redisplay Org-roam overlays."
+  (org-roam-overlay-disable)
+  (org-roam-overlay-enable))
+
+(define-minor-mode org-roam-overlay-mode
+  "Overlays for Org-roam ID links.
+Org-roam overlay mode is a minor mode.  When enabled,
+overlay displaying the node's title is displayed."
+  :lighter " org-roam-overlay"
+  (if org-roam-overlay-mode
+      (progn
+        (org-roam-overlay-enable)
+        (add-hook 'after-save-hook #'org-roam-overlay-redisplay nil t))
+    (org-roam-overlay-disable)
+    (remove-hook 'after-save-hook #'org-roam-overlay-redisplay t)))
+
+(provide 'org-roam-overlay)
+;;; org-roam-overlay.el ends here