/**
 * client-x
 *   A really simple D-Bus Client which speaks to server-x
 *
 *   Copyright (c) 2013 Samuel A. Rebelsky.  All rights reserved.
 *
 *   This file is part of the Glimmer Guide to writing D-Bus Clients (GGDBC).
 *
 *   GGDBC is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   GGDBC is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with GGDBC.  If not, see <http://www.gnu.org/licenses/>.
 */


// +---------+---------------------------------------------------------
// | Headers |
// +---------+

#include <stdio.h>      // We use fprintf for error messages during
                        // development.

#include <gio/gio.h>    // For the GDBus functions.


// +---------+---------------------------------------------------------
// | Globals |
// +---------+

/**
 * The name of the service.
 */
static const gchar service[] = "edu.grinnell.glimmer.guide.SampleServerY";

/** 
 * The name of the object.
 */
static const gchar object[] = "/edu/grinnell/glimmer/guide/SampleObjectX";

/**
 * And the name of the interface.
 */
static const gchar interface[] = "edu.grinnell.glimmer.guide.SampleInterfaceX";


// +------+------------------------------------------------------------
// | Main |
// +------+

int
main (int argc, char *argv[])
{
  GError *error = NULL; // Some functions return errors through params
  GDBusProxy *proxy;    // The proxy that we work with
  GVariant *params;     // The parameters to a function call
  GVariant *result;   // The value result from a call

  // Prepare to use GLib
  g_type_init ();

  // Create the proxy
  proxy = g_dbus_proxy_new_for_bus_sync (G_BUS_TYPE_SESSION,
                                         G_DBUS_PROXY_FLAGS_NONE,
                                         NULL,
                                         service,
                                         object,
                                         interface,
                                         NULL,
                                         &error);

  // Check for success
  if ((proxy == NULL) || (error != NULL))
    {
      fprintf (stderr, "Could not connect to %s:%s on %s.\n", 
               service, object, interface);
      if (error != NULL)
        {
          fprintf (stderr, "  %s\n", error->message);
        }
      return 1;
    }

  // Send a message
  params = g_variant_new ("()");
  result = g_dbus_proxy_call_sync (proxy, 
                                   "HelloWorld",
                                   params,
                                   0,
                                   -1,
                                   NULL,
                                   &error);
  
  // Check whether an error occurred.
  if (result == NULL)
    {
      if (error != NULL)
        {
          fprintf (stderr, "Call failed because %s.\n", error->message);
        } // if we got an error
      else
        {
          fprintf (stderr, "Call failed for an unknown reason.\n");
        }
      return 1; // Give up!
    } // if no value was result

  // Okay, we got a value back.  Deal with it.
  else
    {
      gchar *str;
      g_variant_get (result, "(&s)", &str);
      printf ("The function result is %s\n", str);
    } // succcessfully got a result

  // Send a message
  params = g_variant_new ("(d)", 3.0);
  result = g_dbus_proxy_call_sync (proxy, 
                                   "circle",
                                   params,
                                   0,
                                   -1,
                                   NULL,
                                   &error);
  
  // Check whether an error occurred.
  if (result == NULL)
    {
      if (error != NULL)
        {
          fprintf (stderr, "Call failed because %s.\n", error->message);
        } // if we got an error
      else
        {
          fprintf (stderr, "Call failed for an unknown reason.\n");
        }
      return 1; // Give up!
    } // if no value was result

  // Okay, we got a value back.  Deal with it.
  else
    {
      double area, circumference;
      g_variant_get (result, "(dd)", &area, &circumference);
      printf ("Area: %lf, Circumference: %lf\n", area, circumference);
    } // succcessfully got a result

  // Clean up
  g_object_unref (proxy);
  g_variant_unref (params);
  g_variant_unref (result);

  // And we're done
  return 0;
} // main