(bugfix): Use predicate to check for a `org-roam-capture` process (#413)

Instead of using a global variable to check for a existing capture,
leverage the :org-roam plist property of the buffer-local variable
`org-roam-capture-current-plist`.

This prevents a lockout if the capture buffer is killed

org-roam-capture.el

@@ -72,9 +72,6 @@ The `ref' context is used by `org-roam-protocol', where the
 capture process is triggered upon trying to find or create a new
 note with the given `ref'.")
 
-(defvar org-roam-capture--in-process nil
-  "Boolean tracking whether Org-roam captures are in-process.")
-
 (defvar org-roam-capture-additional-template-props nil
   "Additional props to be added to the Org-roam template.")
 
@@ -129,6 +126,13 @@ Details on how to specify for the template is given in `org-roam-capture-templat
     (setq org-capture-plist
           (plist-put org-capture-plist :org-roam p))))
 
+(defun org-roam-capture--in-process-p ()
+  "Return non-nil if a `org-roam-capture' buffer exists."
+  (cl-some (lambda (buffer)
+	     (and (eq (buffer-local-value 'major-mode (current-buffer)) 'org-mode)
+		  (plist-get (buffer-local-value 'org-capture-current-plist (current-buffer)) :org-roam)))
+	   (buffer-list)))
+
 (defun org-roam-capture--fill-template (str &optional info)
   "Expands the template STR, returning the string.
 This is an extension of org-capture's template expansion.
@@ -268,15 +272,10 @@ This function is used solely in Org-roam's capture templates: see
       (let ((prop (pop org-roam-capture-additional-template-props))
             (val (pop org-roam-capture-additional-template-props)))
         (org-roam-capture--put prop val)))
-    (setq org-roam-capture--in-process t)
     (set-buffer (org-capture-target-buffer file-path))
     (widen)
     (goto-char (point-max))))
 
-(defun org-roam-capture--cleanup-h ()
-  "Cleans up after an Org-roam capture process."
-  (setq org-roam-capture--in-process nil))
-
 (defun org-roam-capture--convert-template (template)
   "Convert TEMPLATE from Org-roam syntax to `org-capture-templates' syntax."
   (let* ((copy (copy-tree template))
@@ -306,7 +305,6 @@ GOTO and KEYS argument have the same functionality as
     (when (= (length org-capture-templates) 1)
       (setq keys (caar org-capture-templates)))
     (add-hook 'org-capture-after-finalize-hook #'org-roam-capture--save-file-maybe-h)
-    (add-hook 'org-capture-after-finalize-hook #'org-roam-capture--cleanup-h 10)
     (org-capture goto keys)))
 
 ;;;###autoload
@@ -314,7 +312,7 @@ GOTO and KEYS argument have the same functionality as
   "Launches an `org-capture' process for a new or existing note.
 This uses the templates defined at `org-roam-capture-templates'."
   (interactive)
-  (when org-roam-capture--in-process
+  (when (org-roam-capture--in-process-p)
     (user-error "Nested Org-roam capture processes not supported"))
   (let* ((completions (org-roam--get-title-path-completions))
          (title (org-roam-completion--completing-read "File: " completions))

org-roam.el

@@ -335,16 +335,16 @@ If PREFIX, downcase the title before insertion."
           (when region ;; Remove previously selected text.
             (delete-region (car region) (cdr region)))
           (insert (org-roam--format-link target-file-path link-description)))
-      (if org-roam-capture--in-process
-          (user-error "Nested Org-roam capture processes not supported")
-        (let ((org-roam-capture--info (list (cons 'title title)
-                                            (cons 'slug (org-roam--title-to-slug title))))
-              (org-roam-capture--context 'title))
-          (add-hook 'org-capture-after-finalize-hook #'org-roam-capture--insert-link-h)
-          (setq org-roam-capture-additional-template-props (list :region region
-                                                                 :link-description link-description
-                                                                 :capture-fn 'org-roam-insert))
-          (org-roam--capture))))))
+      (when (org-roam-capture--in-process-p)
+	(user-error "Nested Org-roam capture processes not supported"))
+      (let ((org-roam-capture--info (list (cons 'title title)
+					  (cons 'slug (org-roam--title-to-slug title))))
+	    (org-roam-capture--context 'title))
+	(add-hook 'org-capture-after-finalize-hook #'org-roam-capture--insert-link-h)
+	(setq org-roam-capture-additional-template-props (list :region region
+							       :link-description link-description
+							       :capture-fn 'org-roam-insert))
+	(org-roam--capture)))))
 
 ;;;; org-roam-find-file
 (defun org-roam--get-title-path-completions ()
@@ -371,7 +371,7 @@ INITIAL-PROMPT is the initial title prompt."
          (file-path (cdr (assoc title completions))))
     (if file-path
         (find-file file-path)
-      (if org-roam-capture--in-process
+      (if (org-roam-capture--in-process-p)
           (user-error "Org-roam capture in process")
         (let ((org-roam-capture--info (list (cons 'title title)
                                             (cons 'slug (org-roam--title-to-slug title))))