[evolution] Remember back up file extension and default to .tar.gz again

[Milan Crha <mcrha src gnome org>]

commit 65e6562ecaa4d1de5f1fa34f99c9ba2d3e3acf08
Author: Milan Crha <mcrha redhat com>
Date:   Thu Sep 14 17:18:55 2017 +0200

    Remember back up file extension and default to .tar.gz again
    
    The default had been .tar.xz, but as claimed in [1], it makes back up
    significantly slower with not much gain on the back up file size. This
    change adds a setting to remember what file type had been used the last
    time and it is reused the next time the back up is invoked.
    
    [1] https://bugzilla.redhat.com/show_bug.cgi?id=1491024

 data/org.gnome.evolution.shell.gschema.xml.in      |    5 ++
 .../backup-restore/evolution-backup-restore.c      |   41 +++++++++++++++++--
 2 files changed, 41 insertions(+), 5 deletions(-)
---
diff --git a/data/org.gnome.evolution.shell.gschema.xml.in b/data/org.gnome.evolution.shell.gschema.xml.in
index c42dc8e..7c27dba 100644
--- a/data/org.gnome.evolution.shell.gschema.xml.in
+++ b/data/org.gnome.evolution.shell.gschema.xml.in
@@ -120,6 +120,11 @@
       <_summary>Enable special WebKit developer features</_summary>
       <_description>Any change of this option requires restart of Evolution.</_description>
     </key>
+    <key name="backup-restore-extension" type="s">
+      <default>''</default>
+      <_summary>The last extension being used when backing up Evolution data.</_summary>
+      <_description>It can be either '.gz' or '.xz' and it influences what extension will be preselected in 
the file chooser.</_description>
+    </key>
     <child name="window" schema="org.gnome.evolution.window"/>
   </schema>
 </schemalist>
diff --git a/src/modules/backup-restore/evolution-backup-restore.c 
b/src/modules/backup-restore/evolution-backup-restore.c
index f3d183d..0e8e614 100644
--- a/src/modules/backup-restore/evolution-backup-restore.c
+++ b/src/modules/backup-restore/evolution-backup-restore.c
@@ -231,8 +231,21 @@ set_local_only (GtkFileChooser *file_chooser,
         *     takes a filename argument, not a URI. */
        gtk_file_chooser_set_local_only (file_chooser, TRUE);
 
-       /* Not NULL when saving file. */
+       /* Not NULL when saving file, contains the suggested file name. */
        if (user_data) {
+               GSList *filters;
+
+               filters = gtk_file_chooser_list_filters (file_chooser);
+
+               if (g_slist_length (filters) > 2) {
+                       if (g_str_has_suffix (user_data, ".xz"))
+                               gtk_file_chooser_set_filter (file_chooser, filters->data);
+                       else
+                               gtk_file_chooser_set_filter (file_chooser, filters->next->data);
+               }
+
+               g_slist_free (filters);
+
                g_signal_connect (file_chooser, "notify::filter",
                        G_CALLBACK (file_chooser_filter_changed_cb), NULL);
        }
@@ -274,22 +287,40 @@ action_settings_backup_cb (GtkAction *action,
        GFileInfo *file_info;
        const gchar *attribute;
        GError *error = NULL;
-       gchar *suggest;
+       gchar *suggest, *tmp;
        gboolean has_xz;
+       GSettings *settings;
+
+       settings = e_util_ref_settings ("org.gnome.evolution.shell");
+       tmp = g_settings_get_string (settings, "backup-restore-extension");
 
        has_xz = is_xz_available ();
-       suggest = suggest_file_name (has_xz ? ".xz" : ".gz");
+       suggest = suggest_file_name ((has_xz && g_strcmp0 (tmp, ".xz") == 0) ? ".xz" : ".gz");
+
+       g_free (tmp);
 
        file = e_shell_run_save_dialog (
                e_shell_window_get_shell (shell_window),
                _("Select name of the Evolution backup file"),
                suggest, has_xz ? "*.tar.xz;*.tar.gz" : "*.tar.gz", (GtkCallback)
-               set_local_only, has_xz ? GINT_TO_POINTER (1) : NULL);
+               set_local_only, has_xz ? suggest : NULL);
 
        g_free (suggest);
 
-       if (file == NULL)
+       if (file == NULL) {
+               g_object_unref (settings);
                return;
+       }
+
+       tmp = g_file_get_path (file);
+
+       if (tmp && g_str_has_suffix (tmp, ".xz"))
+               g_settings_set_string (settings, "backup-restore-extension", ".xz");
+       else if (tmp && g_str_has_suffix (tmp, ".gz"))
+               g_settings_set_string (settings, "backup-restore-extension", ".gz");
+
+       g_object_unref (settings);
+       g_free (tmp);
 
        /* Make sure the parent directory can be written to. */