[rygel] core: Add changed signals emission to MetaConfig

[Jens Georg <jensgeorg src gnome org>]

commit 0396c7846d35bc83a82dd0b74f1a5e0ed5a98bf3
Author: Krzesimir Nowak <krnowak openismus com>
Date:   Tue Sep 18 13:03:55 2012 +0200

    core: Add changed signals emission to MetaConfig
    
    RygelMetaConfig emits signals only when one of its backends emit such
    signals and its value is taken from settings getter. For example, if
    we set interface in command line and RygelUserConfig emits a signal
    about interface change, RygelMetaConfig is going to ignore it, as
    interface value is taken from command line settings.

 src/librygel-core/rygel-meta-config.vala |  132 ++++++++++++++++++++++++++++++
 1 files changed, 132 insertions(+), 0 deletions(-)
---
diff --git a/src/librygel-core/rygel-meta-config.vala b/src/librygel-core/rygel-meta-config.vala
index 1e8a955..2ce4be3 100644
--- a/src/librygel-core/rygel-meta-config.vala
+++ b/src/librygel-core/rygel-meta-config.vala
@@ -2,10 +2,12 @@
  * Copyright (C) 2008,2009 Nokia Corporation.
  * Copyright (C) 2008,2009 Zeeshan Ali (Khattak) <zeeshanak gnome org>.
  * Copyright (C) 2012 Openismus GmbH.
+ * Copyright (C) 2012 Intel Corporation
  *
  * Author: Zeeshan Ali (Khattak) <zeeshanak gnome org>
  *                               <zeeshan ali nokia com>
  *         Jens Georg <jensg openismus com>
+ *         Krzesimir Nowak <krnowak openismus com>
  *
  * This file is part of Rygel.
  *
@@ -39,6 +41,12 @@ public class Rygel.MetaConfig : GLib.Object, Configuration {
 
     private static ArrayList<Configuration> configs;
 
+    private void connect_signals (Configuration config) {
+        config.configuration_changed.connect (this.on_configuration_changed);
+        config.section_changed.connect (this.on_section_changed);
+        config.setting_changed.connect (this.on_setting_changed);
+    }
+
     public static MetaConfig get_default () {
         if (MetaConfig.configs == null) {
             MetaConfig.configs = new ArrayList<Configuration> ();
@@ -46,6 +54,10 @@ public class Rygel.MetaConfig : GLib.Object, Configuration {
 
         if (meta_config == null) {
             meta_config = new MetaConfig ();
+
+            foreach (var config in MetaConfig.configs) {
+                meta_config.connect_signals (config);
+            }
         }
 
         return meta_config;
@@ -56,6 +68,10 @@ public class Rygel.MetaConfig : GLib.Object, Configuration {
             MetaConfig.configs = new ArrayList<Configuration> ();
         }
         configs.add (config);
+
+        if (meta_config != null) {
+            meta_config.connect_signals (config);
+        }
     }
 
     public bool get_upnp_enabled () throws GLib.Error {
@@ -522,4 +538,120 @@ public class Rygel.MetaConfig : GLib.Object, Configuration {
 
         return val;
     }
+
+    private bool configuration_value_available (Configuration config,
+                                                ConfigurationEntry entry) {
+        try {
+            switch (entry) {
+            case ConfigurationEntry.UPNP_ENABLED:
+                config.get_upnp_enabled ();
+                break;
+
+            case ConfigurationEntry.INTERFACE:
+                config.get_interface ();
+                break;
+
+            case ConfigurationEntry.PORT:
+                config.get_port ();
+                break;
+
+            case ConfigurationEntry.TRANSCODING:
+                config.get_transcoding ();
+                break;
+
+            case ConfigurationEntry.ALLOW_UPLOAD:
+                config.get_allow_upload ();
+                break;
+
+            case ConfigurationEntry.ALLOW_DELETION:
+                config.get_allow_deletion ();
+                break;
+
+            case ConfigurationEntry.LOG_LEVELS:
+                config.get_log_levels ();
+                break;
+
+            case ConfigurationEntry.PLUGIN_PATH:
+                config.get_plugin_path ();
+                break;
+
+            case ConfigurationEntry.VIDEO_UPLOAD_FOLDER:
+                config.get_video_upload_folder ();
+                break;
+
+            case ConfigurationEntry.MUSIC_UPLOAD_FOLDER:
+                config.get_music_upload_folder ();
+                break;
+
+            case ConfigurationEntry.PICTURE_UPLOAD_FOLDER:
+                config.get_picture_upload_folder ();
+                break;
+
+            default:
+                assert_not_reached ();
+            }
+        } catch (GLib.Error e) {
+            return false;
+        }
+
+        return true;
+    }
+
+    private void on_configuration_changed (Configuration affected_config,
+                                           ConfigurationEntry entry) {
+        foreach (var config in MetaConfig.configs) {
+            if (config == affected_config) {
+                this.configuration_changed (entry);
+            } else {
+                if (configuration_value_available (config, entry)) {
+                    return;
+                }
+            }
+        }
+    }
+
+    private bool setting_value_available (Configuration config,
+                                          string section,
+                                          SectionEntry entry) {
+        try {
+            switch (entry) {
+            case SectionEntry.TITLE:
+                config.get_title (section);
+                break;
+
+            case SectionEntry.ENABLED:
+                config.get_enabled (section);
+                break;
+
+            default:
+                assert_not_reached ();
+            }
+        } catch (GLib.Error e) {
+            return false;
+        }
+
+        return true;
+    }
+
+    private void on_section_changed (Configuration affected_config,
+                                     string section,
+                                     SectionEntry entry) {
+        foreach (var config in MetaConfig.configs) {
+            if (config == affected_config) {
+                this.section_changed (section, entry);
+            } else {
+                if (setting_value_available (config, section, entry)) {
+                    return;
+                }
+            }
+        }
+    }
+
+    private void on_setting_changed (Configuration affected_config,
+                                     string section,
+                                     string key) {
+        // The section and key here is actually a catch-wrestling.
+        // We emit the setting changed straight away.
+        this.setting_changed (section, key);
+    }
 }