From b0a841c63ae86c50fa309b6396c8dd82f07fcefc Mon Sep 17 00:00:00 2001
From: Frederico Gomes <fredericojfgomes@gmail.com>
Date: Mon, 26 Jan 2026 12:39:19 +0000
Subject: [PATCH] wireguard: Show next available client IP in Add Client form

Display the next available IP address that will be
automatically assigned when adding a new client.

Helps admins know what client IP to provide when configuring client
connections back to this server.

Signed-off-by: Frederico Gomes <fredericojfgomes@gmail.com>
[sunil: Turn the IP address styling into a form element]
[sunil: Update the comment style for consistency]
[sunil: Update the label for clarity]
Signed-off-by: Sunil Mohan Adapa <sunil@medhas.org>
Reviewed-by: Sunil Mohan Adapa <sunil@medhas.org>
---
 .../wireguard/templates/wireguard_add_client.html    | 12 ++++++++++++
 plinth/modules/wireguard/views.py                    | 10 ++++++++++
 2 files changed, 22 insertions(+)

diff --git a/plinth/modules/wireguard/templates/wireguard_add_client.html b/plinth/modules/wireguard/templates/wireguard_add_client.html
index 466f2d011..909066ddd 100644
--- a/plinth/modules/wireguard/templates/wireguard_add_client.html
+++ b/plinth/modules/wireguard/templates/wireguard_add_client.html
@@ -15,6 +15,18 @@
 
     {{ form|bootstrap }}
 
+    {% if next_ip %}
+      <div class="form-group">
+        <label for="id_next_ip" class="control-label">
+          {% trans "IP address that will be assigned to this client" %}
+        </label>
+        <div>
+          <input type="text" id="id_next_ip" class="form-control"
+                 value="{{ next_ip }}" disabled="disabled">
+        </div>
+      </div>
+    {% endif %}
+
     <input type="submit" class="btn btn-primary"
            value="{% trans "Add Client" %}"/>
   </form>
diff --git a/plinth/modules/wireguard/views.py b/plinth/modules/wireguard/views.py
index 48fcc45f8..5de984006 100644
--- a/plinth/modules/wireguard/views.py
+++ b/plinth/modules/wireguard/views.py
@@ -46,6 +46,16 @@ class AddClientView(SuccessMessageMixin, FormView):
         """Return additional context for rendering the template."""
         context = super().get_context_data(**kwargs)
         context['title'] = _('Add Allowed Client')
+
+        # Show next available IP.
+        try:
+            connection = utils._server_connection()
+            setting_name = utils.nm.SETTING_WIREGUARD_SETTING_NAME
+            settings = connection.get_setting_by_name(setting_name)
+            context['next_ip'] = utils._get_next_available_ip_address(settings)
+        except Exception:
+            context['next_ip'] = None
+
         return context
 
     def form_valid(self, form):