[gnome-initial-setup/youre-welcome: 3/10] Read GNOME version from the official location

[Matthias Clasen <matthiasc src gnome org>]

commit d5fba0c31bf23d158972e61da06e4c0b88d88e05
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Aug 5 21:12:45 2020 -0400

    Read GNOME version from the official location
    
    Read /usr/share/gnome/gnome-version.xml to find the
    version number.

 .../pages/welcome/gis-welcome-page.c               | 141 +++++++++++++++++++++
 .../pages/welcome/gis-welcome-page.ui              |  10 +-
 meson.build                                        |   1 +
 3 files changed, 147 insertions(+), 5 deletions(-)
---
diff --git a/gnome-initial-setup/pages/welcome/gis-welcome-page.c 
b/gnome-initial-setup/pages/welcome/gis-welcome-page.c
index 540249ef..519b9397 100644
--- a/gnome-initial-setup/pages/welcome/gis-welcome-page.c
+++ b/gnome-initial-setup/pages/welcome/gis-welcome-page.c
@@ -31,6 +31,7 @@
 struct _GisWelcomePagePrivate
 {
   GtkWidget *header;
+  GtkWidget *title;
 };
 typedef struct _GisWelcomePagePrivate GisWelcomePagePrivate;
 
@@ -48,6 +49,144 @@ update_welcome_header (GisWelcomePage *page)
   g_object_unref (pixbuf);
 }
 
+typedef struct
+{
+  char *major;
+  char *minor;
+  char *micro;
+  char *distributor;
+  char *date;
+  char **current;
+} VersionData;
+
+static void
+version_data_free (VersionData *data)
+{
+  g_free (data->major);
+  g_free (data->minor);
+  g_free (data->micro);
+  g_free (data->distributor);
+  g_free (data->date);
+  g_free (data);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (VersionData, version_data_free);
+
+static void
+version_start_element_handler (GMarkupParseContext      *ctx,
+                               const char               *element_name,
+                               const char              **attr_names,
+                               const char              **attr_values,
+                               gpointer                  user_data,
+                               GError                  **error)
+{
+  VersionData *data = user_data;
+  if (g_str_equal (element_name, "platform"))
+    data->current = &data->major;
+  else if (g_str_equal (element_name, "minor"))
+    data->current = &data->minor;
+  else if (g_str_equal (element_name, "micro"))
+    data->current = &data->micro;
+  else if (g_str_equal (element_name, "distributor"))
+    data->current = &data->distributor;
+  else if (g_str_equal (element_name, "date"))
+    data->current = &data->date;
+  else
+    data->current = NULL;
+}
+
+static void
+version_end_element_handler (GMarkupParseContext      *ctx,
+                             const char               *element_name,
+                             gpointer                  user_data,
+                             GError                  **error)
+{
+  VersionData *data = user_data;
+  data->current = NULL;
+}
+
+static void
+version_text_handler (GMarkupParseContext *ctx,
+                      const char          *text,
+                      gsize                text_len,
+                      gpointer             user_data,
+                      GError             **error)
+{
+  VersionData *data = user_data;
+  if (data->current != NULL)
+    {
+      g_autofree char *stripped = NULL;
+
+      stripped = g_strstrip (g_strdup (text));
+      g_free (*data->current);
+      *data->current = g_strdup (stripped);
+    }
+}
+
+static gboolean
+load_gnome_version (char **version,
+                    char **distributor,
+                    char **date)
+{
+  GMarkupParser version_parser = {
+    version_start_element_handler,
+    version_end_element_handler,
+    version_text_handler,
+    NULL,
+    NULL,
+  };
+  g_autoptr(GError) error = NULL;
+  g_autoptr(GMarkupParseContext) ctx = NULL;
+  g_autofree char *contents = NULL;
+  gsize length;
+  g_autoptr(VersionData) data = NULL;
+
+  if (!g_file_get_contents (DATADIR "/gnome/gnome-version.xml",
+                            &contents,
+                            &length,
+                            &error))
+    return FALSE;
+
+  data = g_new0 (VersionData, 1);
+  ctx = g_markup_parse_context_new (&version_parser, 0, data, NULL);
+  if (!g_markup_parse_context_parse (ctx, contents, length, &error))
+    {
+      g_warning ("Invalid version file: '%s'", error->message);
+    }
+  else
+    {
+      if (version != NULL)
+        {
+          if (strcmp (data->micro, "0") == 0)
+            *version = g_strdup_printf ("%s.%s", data->major, data->minor);
+          else
+            *version = g_strdup_printf ("%s.%s.%s", data->major, data->minor, data->micro);
+        }
+
+      if (distributor != NULL)
+        *distributor = g_strdup (data->distributor);
+      if (date != NULL)
+        *date = g_strdup (data->date);
+
+      return TRUE;
+    }
+
+  return FALSE;
+};
+
+static void
+update_welcome_title (GisWelcomePage *page)
+{
+  GisWelcomePagePrivate *priv = gis_welcome_page_get_instance_private (page);
+  g_autofree char *version = NULL;
+  g_autofree char *text = NULL;
+
+  load_gnome_version (&version, NULL, NULL);
+  text = g_strdup_printf (_("Welcome to GNOME %s !"), version);
+
+  gtk_label_set_label (GTK_LABEL (priv->title), text);
+}
+
 static void
 gis_welcome_page_constructed (GObject *object)
 {
@@ -56,6 +195,7 @@ gis_welcome_page_constructed (GObject *object)
   G_OBJECT_CLASS (gis_welcome_page_parent_class)->constructed (object);
 
   update_welcome_header (page);
+  update_welcome_title (page);
 
   gis_page_set_complete (GIS_PAGE (page), TRUE);
   gtk_widget_show (GTK_WIDGET (page));
@@ -80,6 +220,7 @@ gis_welcome_page_class_init (GisWelcomePageClass *klass)
   gtk_widget_class_set_template_from_resource (GTK_WIDGET_CLASS (klass), 
"/org/gnome/initial-setup/gis-welcome-page.ui");
 
   gtk_widget_class_bind_template_child_private (GTK_WIDGET_CLASS (klass), GisWelcomePage, header);
+  gtk_widget_class_bind_template_child_private (GTK_WIDGET_CLASS (klass), GisWelcomePage, title);
   gtk_widget_class_bind_template_callback (GTK_WIDGET_CLASS (klass), start_setup);
 
   page_class->page_id = PAGE_ID;
diff --git a/gnome-initial-setup/pages/welcome/gis-welcome-page.ui 
b/gnome-initial-setup/pages/welcome/gis-welcome-page.ui
index 3a4a6ee8..2df449f3 100644
--- a/gnome-initial-setup/pages/welcome/gis-welcome-page.ui
+++ b/gnome-initial-setup/pages/welcome/gis-welcome-page.ui
@@ -28,12 +28,12 @@
             <property name="valign">center</property>
             <property name="spacing">20</property>
             <child>
-              <object class="GtkLabel">
+              <object class="GtkLabel" id="title">
                  <property name="visible">True</property>
-                 <property name="label" translatable="yes">Welcome to GNOME 3.38!</property>
-                 <attributes>
-                   <attribute name="scale" value="1.6"/>
-                 </attributes>
+                 <property name="label">Welcome to the latest GNOME!</property>
+                 <style>
+                   <class name="title-1"/>
+                 </style>
               </object>
             </child>
             <child>
diff --git a/meson.build b/meson.build
index 506707d4..9838aa2f 100644
--- a/meson.build
+++ b/meson.build
@@ -23,6 +23,7 @@ conf = configuration_data()
 conf.set_quoted('GETTEXT_PACKAGE', meson.project_name())
 conf.set_quoted('GNOMELOCALEDIR', locale_dir)
 conf.set_quoted('PKGDATADIR', pkgdata_dir)
+conf.set_quoted('DATADIR', data_dir)
 conf.set_quoted('PKGSYSCONFDIR', pkgsysconf_dir)
 conf.set('SECRET_API_SUBJECT_TO_CHANGE', true)
 conf.set_quoted('G_LOG_DOMAIN', 'InitialSetup')