[evolution] I#120 - Show security bar above message headers

[Milan Crha <mcrha src gnome org>]

commit 9c55a311325f5905d8b8403b96607e46cf343f21
Author: Milan Crha <mcrha redhat com>
Date:   Mon Oct 22 18:53:28 2018 +0200

    I#120 - Show security bar above message headers
    
    Closes https://gitlab.gnome.org/GNOME/evolution/issues/120

 src/em-format/e-mail-parser.c | 63 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 63 insertions(+)
---
diff --git a/src/em-format/e-mail-parser.c b/src/em-format/e-mail-parser.c
index 793d891dfc..c81bcc2aca 100644
--- a/src/em-format/e-mail-parser.c
+++ b/src/em-format/e-mail-parser.c
@@ -79,6 +79,67 @@ GType e_mail_parser_application_smime_get_type (void);
 
 static gpointer parent_class;
 
+static void
+mail_parser_move_security_before_headers (GQueue *part_queue)
+{
+       GList *link, *last_headers = NULL;
+       GSList *headers_stack = NULL;
+
+       link = g_queue_peek_head_link (part_queue);
+       while (link) {
+               EMailPart *part = link->data;
+               const gchar *id;
+
+               if (!part) {
+                       link = g_list_next (link);
+                       continue;
+               }
+
+               id = e_mail_part_get_id (part);
+               if (!id) {
+                       link = g_list_next (link);
+                       continue;
+               }
+
+               if (g_str_has_suffix (id, ".rfc822")) {
+                       headers_stack = g_slist_prepend (headers_stack, last_headers);
+                       last_headers = NULL;
+               } else if (g_str_has_suffix (id, ".rfc822.end")) {
+                       g_warn_if_fail (headers_stack != NULL);
+
+                       if (headers_stack) {
+                               last_headers = headers_stack->data;
+                               headers_stack = g_slist_remove (headers_stack, last_headers);
+                       } else {
+                               last_headers = NULL;
+                       }
+               }
+
+               if (g_strcmp0 (e_mail_part_get_mime_type (part), "application/vnd.evolution.headers") == 0) {
+                       last_headers = link;
+                       link = g_list_next (link);
+               } else if (g_strcmp0 (e_mail_part_get_mime_type (part), 
"application/vnd.evolution.secure-button") == 0) {
+                       g_warn_if_fail (last_headers != NULL);
+
+                       if (last_headers) {
+                               GList *next = g_list_next (link);
+
+                               g_warn_if_fail (g_queue_remove (part_queue, part));
+                               g_queue_insert_before (part_queue, last_headers, part);
+
+                               link = next;
+                       } else {
+                               link = g_list_next (link);
+                       }
+               } else {
+                       link = g_list_next (link);
+               }
+       }
+
+       g_warn_if_fail (headers_stack == NULL);
+       g_slist_free (headers_stack);
+}
+
 static void
 mail_parser_run (EMailParser *parser,
                  EMailPartList *part_list,
@@ -142,6 +203,8 @@ mail_parser_run (EMailParser *parser,
                        break;
        }
 
+       mail_parser_move_security_before_headers (&mail_part_queue);
+
        while (!g_queue_is_empty (&mail_part_queue)) {
                mail_part = g_queue_pop_head (&mail_part_queue);
                e_mail_part_list_add_part (part_list, mail_part);