fix: guard magic shelf nav links and pass route flags to templates

Author: crocodilestick

CONTRIBUTORS

@@ -315,7 +315,7 @@ Copyright (C) 2024-2026 Calibre-Web Automated contributors
 - zhiyue (1 commits)
 # Fork Contributors (crocodilestick/calibre-web-automated)
 
-- crocodilestick (958 commits)
+- crocodilestick (962 commits)
 - jmarmstrong1207 (73 commits)
 - demitrix (30 commits)
 - sirwolfgang (29 commits)

cps/render_template.py

@@ -5,7 +5,7 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
 # See CONTRIBUTORS for full list of authors.
 
-from flask import render_template, g, abort, request, flash
+from flask import render_template, g, abort, request, flash, current_app
 from flask_babel import gettext as _
 from flask_babel import get_locale
 import polib
@@ -224,6 +224,13 @@ def translations_missing_notification() -> None:
 # Returns the template for rendering and includes the instance name
 def render_title_template(*args, **kwargs):
     sidebar, simple = get_sidebar_config(kwargs)
+    try:
+        magic_shelf_routes = {
+            "render": 'web.render_magic_shelf' in current_app.view_functions,
+            "create": 'web.create_magic_shelf' in current_app.view_functions,
+        }
+    except Exception:
+        magic_shelf_routes = {"render": False, "create": False}
     if current_user.role_admin():
         try:
             cwa_update_notification()
@@ -241,8 +248,9 @@ def render_title_template(*args, **kwargs):
         print(f"[translation-notification-service] The following error occurred when checking for missing translations:\n{e}", flush=True)
     try:
         return render_template(instance=config.config_calibre_web_title, sidebar=sidebar, simple=simple,
-                               accept=config.config_upload_formats.split(','),
-                               *args, **kwargs)
+                       accept=config.config_upload_formats.split(','),
+                       magic_shelf_routes=magic_shelf_routes,
+                       *args, **kwargs)
     except PermissionError:
         log.error("No permission to access {} file.".format(args[0]))
         abort(403)

cps/templates/layout.html

@@ -301,12 +301,14 @@ <h3>{{_('Uploading...')}}</h3>
                 <li id="nav_createshelf" class="create-shelf"><a href="{{url_for('shelf.create_shelf')}}">{{_('Create Shelf')}}</a></li>
               {% endif %}
               {% endif %}
-              {% if current_user.is_authenticated %}
+              {% if current_user.is_authenticated and magic_shelf_routes.render %}
                 <li class="nav-head hidden-xs" style="margin-top: 1rem;">{{_('Magic Shelves ✨')}}</li>
                   {% for shelf in g.magic_shelves_access %}
                     <li><a href="{{url_for('web.render_magic_shelf', shelf_id=shelf.id)}}" title="{{shelf.name}} ({{shelf.book_count}})"><span style="font-size: 14px;">{{shelf.icon}}</span> {{shelf.name|shortentitle(40)}}{% if shelf.is_public == 1 %} {{_('(Public)')}}{% endif %} <span style="font-size: 80%; color: #888;">({{shelf.book_count}})</span></a></li>
                   {% endfor %}
-                <li id="nav_createmagicshelf" class="create-shelf"><a href="{{url_for('web.create_magic_shelf')}}" style="display: flex; align-items: center;">{{_('Create Magic Shelf')}}</a></li>
+                {% if magic_shelf_routes.create %}
+                  <li id="nav_createmagicshelf" class="create-shelf"><a href="{{url_for('web.create_magic_shelf')}}" style="display: flex; align-items: center;">{{_('Create Magic Shelf')}}</a></li>
+                {% endif %}
               {% endif %}
               {% if not current_user.is_anonymous %}
                 <li id="nav_about" {% if page == 'stat' %}class="active"{% endif %}><a href="{{url_for('about.stats')}}"><span class="glyphicon glyphicon-info-sign"></span> {{_('About')}}</a></li>