[libgweather] location: use a serialization format compatible with dbus

[Giovanni Campagna <gcampagna src gnome org>]

commit a080505177d844aab4e61993a009e1f6ca285318
Author: Giovanni Campagna <gcampagna src gnome org>
Date:   Thu May 15 22:36:16 2014 +0200

    location: use a serialization format compatible with dbus
    
    We cannot send maybe types on dbus, so instead use an array with
    0 or 1 element (like GApplication does).
    Compatibility with existing serialized GVariants is ensured with
    the version field (so settings are preserved), but newly serialized
    locations use the new format, which is now version 2.

 libgweather/gweather-location.c |  119 ++++++++++++++++++++++++++++++---------
 1 files changed, 93 insertions(+), 26 deletions(-)
---
diff --git a/libgweather/gweather-location.c b/libgweather/gweather-location.c
index 6061269..ac9f8c4 100644
--- a/libgweather/gweather-location.c
+++ b/libgweather/gweather-location.c
@@ -1192,13 +1192,15 @@ gweather_location_equal (GWeatherLocation *one,
 
 /* ------------------- serialization ------------------------------- */
 
-#define FORMAT 1
+#define FORMAT 2
 
 static GVariant *
-gweather_location_format_one_serialize (GWeatherLocation *location)
+gweather_location_format_two_serialize (GWeatherLocation *location)
 {
     const char *name;
     gboolean is_city;
+    GVariantBuilder latlon_builder;
+    GVariantBuilder parent_latlon_builder;
 
     name = location->name;
 
@@ -1210,14 +1212,17 @@ gweather_location_format_one_serialize (GWeatherLocation *location)
        is_city = FALSE;
     }
 
-    return g_variant_new ("(ssbm(dd)m(dd))",
+    g_variant_builder_init (&latlon_builder, G_VARIANT_TYPE ("a(dd)"));
+    if (location->latlon_valid)
+       g_variant_builder_add (&latlon_builder, "(dd)", location->latitude, location->longitude);
+
+    g_variant_builder_init (&parent_latlon_builder, G_VARIANT_TYPE ("a(dd)"));
+    if (location->parent && location->parent->latlon_valid)
+       g_variant_builder_add (&parent_latlon_builder, "(dd)", location->parent->latitude, 
location->parent->longitude);
+
+    return g_variant_new ("(ssba(dd)a(dd))",
                          name, location->station_code, is_city,
-                         location->latlon_valid,
-                         location->latitude,
-                         location->longitude,
-                         location->parent && location->parent->latlon_valid,
-                         location->parent ? location->parent->latitude : 0.0,
-                         location->parent ? location->parent->longitude : 0.0);
+                         &latlon_builder, &parent_latlon_builder);
 }
 
 GWeatherLocation *
@@ -1261,25 +1266,20 @@ _gweather_location_new_detached (GWeatherLocation *nearest_station,
 }
 
 static GWeatherLocation *
-gweather_location_format_one_deserialize (GWeatherLocation *world,
-                                         GVariant         *variant)
+gweather_location_common_deserialize (GWeatherLocation *world,
+                                     const char       *name,
+                                     const char       *station_code,
+                                     gboolean          is_city,
+                                     gboolean          latlon_valid,
+                                     gdouble           latitude,
+                                     gdouble           longitude,
+                                     gboolean          parent_latlon_valid,
+                                     gdouble           parent_latitude,
+                                     gdouble           parent_longitude)
 {
-    const char *name;
-    const char *station_code;
-    gboolean is_city, latlon_valid, parent_latlon_valid;
-    gdouble latitude, longitude, parent_latitude, parent_longitude;
     GList *candidates, *l;
     GWeatherLocation *found;
 
-    /* This one instead is a critical, because format is specified in
-       the containing variant */
-    g_return_val_if_fail (g_variant_is_of_type (variant,
-                                               G_VARIANT_TYPE ("(ssbm(dd)m(dd))")), NULL);
-
-    g_variant_get (variant, "(&s&sbm(dd)m(dd))", &name, &station_code, &is_city,
-                  &latlon_valid, &latitude, &longitude,
-                  &parent_latlon_valid, &parent_latitude, &parent_longitude);
-
     /* First find the list of candidate locations */
     candidates = g_hash_table_lookup (world->metar_code_cache, station_code);
 
@@ -1342,6 +1342,71 @@ gweather_location_format_one_deserialize (GWeatherLocation *world,
        return NULL;
 }
 
+static GWeatherLocation *
+gweather_location_format_one_deserialize (GWeatherLocation *world,
+                                         GVariant         *variant)
+{
+    const char *name;
+    const char *station_code;
+    gboolean is_city, latlon_valid, parent_latlon_valid;
+    gdouble latitude, longitude, parent_latitude, parent_longitude;
+
+    /* This one instead is a critical, because format is specified in
+       the containing variant */
+    g_return_val_if_fail (g_variant_is_of_type (variant,
+                                               G_VARIANT_TYPE ("(ssbm(dd)m(dd))")), NULL);
+
+    g_variant_get (variant, "(&s&sbm(dd)m(dd))", &name, &station_code, &is_city,
+                  &latlon_valid, &latitude, &longitude,
+                  &parent_latlon_valid, &parent_latitude, &parent_longitude);
+
+    return gweather_location_common_deserialize(world, name, station_code, is_city,
+                                               latlon_valid, latitude, longitude,
+                                               parent_latlon_valid, parent_latitude, parent_longitude);
+}
+
+static GWeatherLocation *
+gweather_location_format_two_deserialize (GWeatherLocation *world,
+                                         GVariant         *variant)
+{
+    const char *name;
+    const char *station_code;
+    GVariant *latlon_variant;
+    GVariant *parent_latlon_variant;
+    gboolean is_city, latlon_valid, parent_latlon_valid;
+    gdouble latitude, longitude, parent_latitude, parent_longitude;
+
+    /* This one instead is a critical, because format is specified in
+       the containing variant */
+    g_return_val_if_fail (g_variant_is_of_type (variant,
+                                               G_VARIANT_TYPE ("(ssba(dd)a(dd))")), NULL);
+
+    g_variant_get (variant, "(&s&sb a(dd)@a(dd))", &name, &station_code, &is_city,
+                  &latlon_variant, &parent_latlon_variant);
+
+    if (g_variant_n_children (latlon_variant) > 0) {
+       latlon_valid = TRUE;
+       g_variant_get_child (latlon_variant, 0, "(dd)", &latitude, &longitude);
+    } else {
+       latlon_valid = FALSE;
+       latitude = 0;
+       longitude = 0;
+    }
+
+    if (g_variant_n_children (parent_latlon_variant) > 0) {
+       parent_latlon_valid = TRUE;
+       g_variant_get_child (parent_latlon_variant, 0, "(dd)", &parent_latitude, &parent_longitude);
+    } else {
+       parent_latlon_valid = FALSE;
+       parent_latitude = 0;
+       parent_longitude = 0;
+    }
+
+    return gweather_location_common_deserialize(world, name, station_code, is_city,
+                                               latlon_valid, latitude, longitude,
+                                               parent_latlon_valid, parent_latitude, parent_longitude);
+}
+
 /**
  * gweather_location_serialize:
  * @loc: a city, weather station or detached #GWeatherLocation
@@ -1365,7 +1430,7 @@ gweather_location_serialize (GWeatherLocation *loc)
     g_return_val_if_fail (loc->level >= GWEATHER_LOCATION_CITY, NULL);
 
     return g_variant_new ("(uv)", FORMAT,
-                         gweather_location_format_one_serialize (loc));
+                         gweather_location_format_two_serialize (loc));
 }
 
 /**
@@ -1399,8 +1464,10 @@ gweather_location_deserialize (GWeatherLocation *world,
 
     g_variant_get (serialized, "(uv)", &format, &v);
 
-    if (format == FORMAT)
+    if (format == 1)
        loc = gweather_location_format_one_deserialize (world, v);
+    else if (format == 2)
+       loc = gweather_location_format_two_deserialize (world, v);
     else
        loc = NULL;