From 1b959ac00f91620ea6292b4d98d33f11454a8e56 Mon Sep 17 00:00:00 2001
From: Rob Day <rkd@rkd.me.uk>
Date: Sat, 12 Oct 2019 12:51:21 +0100
Subject: [PATCH] Validate the timezone and display an error if it is invalid

---
 plugins/clock/clock.c | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/plugins/clock/clock.c b/plugins/clock/clock.c
index 64a10735..a152872c 100644
--- a/plugins/clock/clock.c
+++ b/plugins/clock/clock.c
@@ -791,6 +791,42 @@ clock_plugin_validate_entry_text (GtkEditable *entry,
                                           plugin);
 }
 
+static void
+clock_plugin_validate_timezone (GtkEntry *entry, const gchar *format, ClockPlugin *plugin)
+{
+  GtkStyleContext *context;
+  gchar           *filename;
+
+  context = gtk_widget_get_style_context (GTK_WIDGET (entry));
+
+  if (strcmp(format, "") != 0)
+  {
+    filename = g_build_filename (ZONEINFO_DIR, format, NULL);
+
+    if (!g_file_test (filename, G_FILE_TEST_IS_REGULAR))
+      gtk_style_context_add_class (context, "error");
+    else
+      gtk_style_context_remove_class (context, "error");
+  }
+  else
+  {
+    gtk_style_context_remove_class (context, "error");
+  }
+}
+
+
+
+static void
+clock_plugin_validate_entry_tz (GtkEditable *entry,
+                                gpointer user_data)
+{
+  ClockPlugin *plugin = user_data;
+
+  clock_plugin_validate_timezone (GTK_ENTRY (entry),
+                                  gtk_entry_get_text (GTK_ENTRY (entry)),
+                                  plugin);
+}
+
 
 
 static void
@@ -1026,6 +1062,8 @@ clock_plugin_configure_plugin (XfcePanelPlugin *panel_plugin)
 
   object = gtk_builder_get_object (builder, "timezone-name");
   panel_return_if_fail (GTK_IS_ENTRY (object));
+  g_signal_connect (G_OBJECT (object), "changed",
+                    G_CALLBACK (clock_plugin_validate_entry_tz), plugin);
   g_object_bind_property (G_OBJECT (plugin->time), "timezone",
                           G_OBJECT (object), "text",
                           G_BINDING_BIDIRECTIONAL | G_BINDING_SYNC_CREATE);
-- 
2.23.0