Added a new backend API, zoitechat_import_gtk3_theme_archive(const char *archive_path, GError **error), and exposed it in the common header so GTK setup code can call a shared import path instead of inlining extraction logic.

Updated the GTK3 import callback in setup.c to:

    open a file chooser titled Import GTK3 Theme ZIP,

    enforce a ZIP-focused chooser filter (*.zip, *.ZIP),

    call the new backend function,

    show success/failure dialogs through setup_theme_show_message,

    refresh the GTK3 theme list immediately after successful import.

Updated the GTK3 section button label to Import GTK3 Theme ZIP and added/used new translatable strings for the new button text and import messages.

src/common/zoitechat.c

@@ -330,6 +330,75 @@ cleanup:
 	return ok;
 }
 
+gboolean
+zoitechat_import_gtk3_theme_archive (const char *archive_path, GError **error)
+{
+	char *theme_root;
+	char *basename;
+	char *dot;
+	char *dest_dir;
+	char *argv[] = {"unzip", "-o", (char *)archive_path, "-d", NULL, NULL};
+	int status = 0;
+	gboolean ok;
+
+	if (!archive_path)
+	{
+		g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
+		             _("No GTK3 theme archive specified."));
+		return FALSE;
+	}
+
+	theme_root = g_build_filename (g_get_home_dir (), ".themes", NULL);
+	basename = g_path_get_basename (archive_path);
+	if (!basename || basename[0] == '\0')
+	{
+		g_free (theme_root);
+		g_free (basename);
+		g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
+		             _("Failed to determine GTK3 theme name."));
+		return FALSE;
+	}
+
+	dot = strrchr (basename, '.');
+	if (dot)
+		*dot = '\0';
+
+	dest_dir = g_build_filename (theme_root, basename, NULL);
+	if (g_mkdir_with_parents (dest_dir, 0700) != 0)
+	{
+		g_set_error (error, G_FILE_ERROR, g_file_error_from_errno (errno),
+		             _("Failed to create GTK3 theme directory."));
+		g_free (dest_dir);
+		g_free (basename);
+		g_free (theme_root);
+		return FALSE;
+	}
+
+	argv[4] = dest_dir;
+	ok = g_spawn_sync (NULL, argv, NULL, G_SPAWN_SEARCH_PATH, NULL, NULL,
+	                   NULL, NULL, &status, error);
+	if (!ok)
+	{
+		g_free (dest_dir);
+		g_free (basename);
+		g_free (theme_root);
+		return FALSE;
+	}
+
+	if (!g_spawn_check_exit_status (status, error))
+	{
+		g_free (dest_dir);
+		g_free (basename);
+		g_free (theme_root);
+		return FALSE;
+	}
+
+	g_free (dest_dir);
+	g_free (basename);
+	g_free (theme_root);
+	return TRUE;
+}
+
 gboolean
 zoitechat_import_theme (const char *path, GError **error)
 {

src/common/zoitechat.h

@@ -31,6 +31,7 @@
 
 gboolean zoitechat_theme_path_from_arg (const char *arg, char **path_out);
 gboolean zoitechat_import_theme (const char *path, GError **error);
+gboolean zoitechat_import_gtk3_theme_archive (const char *archive_path, GError **error);
 gboolean zoitechat_apply_theme (const char *theme_name, GError **error);
 
 #ifdef USE_OPENSSL

src/fe-gtk/setup.c

@@ -2109,22 +2109,24 @@ setup_theme_gtk3_import_cb (GtkWidget *button, gpointer user_data)
 {
 	setup_theme_ui *ui = user_data;
 	GtkWidget *dialog;
+	GtkFileFilter *filter;
 	gint response;
 	char *archive_path;
-	char *basename;
-	char *dot;
-	char *dest_root;
-	char *dest_dir;
-	char *argv[] = {"unzip", "-o", NULL, "-d", NULL, NULL};
 	GError *error = NULL;
-	int status = 0;
 
-	dialog = gtk_file_chooser_dialog_new (_("Import GTK3 Theme"), GTK_WINDOW (setup_window),
+	dialog = gtk_file_chooser_dialog_new (_("Import GTK3 Theme ZIP"), GTK_WINDOW (setup_window),
 		GTK_FILE_CHOOSER_ACTION_OPEN,
 		_ ("_Cancel"), GTK_RESPONSE_CANCEL,
 		_ ("_Open"), GTK_RESPONSE_ACCEPT,
 		NULL);
 
+	filter = gtk_file_filter_new ();
+	gtk_file_filter_set_name (filter, _("ZIP archives"));
+	gtk_file_filter_add_pattern (filter, "*.zip");
+	gtk_file_filter_add_pattern (filter, "*.ZIP");
+	gtk_file_chooser_add_filter (GTK_FILE_CHOOSER (dialog), filter);
+	gtk_file_chooser_set_filter (GTK_FILE_CHOOSER (dialog), filter);
+
 	response = gtk_dialog_run (GTK_DIALOG (dialog));
 	if (response != GTK_RESPONSE_ACCEPT)
 	{
@@ -2138,38 +2140,23 @@ setup_theme_gtk3_import_cb (GtkWidget *button, gpointer user_data)
 	if (!archive_path)
 		return;
 
-	basename = g_path_get_basename (archive_path);
-	dot = strrchr (basename, '.');
-	if (dot)
-		*dot = '\0';
-
-	dest_root = g_build_filename (g_get_home_dir (), ".themes", NULL);
-	g_mkdir_with_parents (dest_root, 0700);
-	dest_dir = g_build_filename (dest_root, basename, NULL);
-	g_mkdir_with_parents (dest_dir, 0700);
-
-	argv[2] = archive_path;
-	argv[4] = dest_dir;
-	if (!g_spawn_sync (NULL, argv, NULL, G_SPAWN_SEARCH_PATH, NULL, NULL,
-		NULL, NULL, &status, &error)
-		|| !g_spawn_check_exit_status (status, &error))
+	if (!zoitechat_import_gtk3_theme_archive (archive_path, &error))
 	{
 		setup_theme_show_message (GTK_MESSAGE_ERROR,
-			error ? error->message : _("Failed to import GTK3 theme archive."));
+			error ? error->message : _("Failed to import GTK3 theme ZIP archive."));
 		g_clear_error (&error);
 	}
 	else
 	{
-		gtk_label_set_text (GTK_LABEL (ui->gtk3_status_label), _("GTK3 theme imported. Select it and click Apply GTK3 Theme."));
 		setup_theme_populate_gtk3 (ui);
+		gtk_label_set_text (GTK_LABEL (ui->gtk3_status_label), _("GTK3 theme ZIP imported successfully."));
+		setup_theme_show_message (GTK_MESSAGE_INFO, _("GTK3 theme ZIP imported successfully."));
 	}
 
-	g_free (dest_dir);
-	g_free (dest_root);
-	g_free (basename);
 	g_free (archive_path);
 }
 
+
 static void
 setup_theme_gtk3_apply_cb (GtkWidget *button, gpointer user_data)
 {
@@ -2280,7 +2267,7 @@ setup_create_theme_page (void)
 	g_signal_connect (G_OBJECT (ui->gtk3_combo), "changed",
 								G_CALLBACK (setup_theme_gtk3_selection_changed), ui);
 
-	ui->gtk3_import_button = gtk_button_new_with_mnemonic (_("_Import GTK3 Theme"));
+	ui->gtk3_import_button = gtk_button_new_with_mnemonic (_("_Import GTK3 Theme ZIP"));
 	gtk_box_pack_start (GTK_BOX (button_box), ui->gtk3_import_button, FALSE, FALSE, 0);
 	g_signal_connect (G_OBJECT (ui->gtk3_import_button), "clicked",
 								G_CALLBACK (setup_theme_gtk3_import_cb), ui);