[rygel] media-export: Make item creation more robust

[Zeeshan Ali Khattak <zeeshanak src gnome org>]

commit 735951f2c4d07d3496c7979a7d885b19fee5a05f
Author: Jens Georg <mail jensge org>
Date:   Sat Jul 24 19:53:33 2010 +0300

    media-export: Make item creation more robust
    
     - Use the same list of columns in every query dealing with items
     - Add an enum for the column instead of using the number directly
    
    This will hopefully protect against problems that arised before when
    modifying the query only in one place but using the same function on the
    resulting statement.

 .../rygel-media-export-media-cache.vala            |  124 ++++++++++++--------
 1 files changed, 75 insertions(+), 49 deletions(-)
---
diff --git a/src/plugins/media-export/rygel-media-export-media-cache.vala b/src/plugins/media-export/rygel-media-export-media-cache.vala
index 7c17c17..21b8e26 100644
--- a/src/plugins/media-export/rygel-media-export-media-cache.vala
+++ b/src/plugins/media-export/rygel-media-export-media-cache.vala
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009 Jens Georg <mail jensge org>.
+ * Copyright (C) 2009,2010 Jens Georg <mail jensge org>.
  *
  * Author: Jens Georg <mail jensge org>
  *
@@ -32,11 +32,37 @@ public errordomain Rygel.MediaDBError {
     UNSUPPORTED_SEARCH
 }
 
-public enum Rygel.MediaDBObjectType {
+internal enum Rygel.MediaDBObjectType {
     CONTAINER,
     ITEM
 }
 
+internal enum Rygel.DetailColumn {
+    TYPE,
+    TITLE,
+    SIZE,
+    MIME_TYPE,
+    WIDTH,
+    HEIGHT,
+    CLASS,
+    AUTHOR,
+    ALBUM,
+    DATE,
+    BITRATE,
+    SAMPLE_FREQ,
+    BITS_PER_SAMPLE,
+    CHANNELS,
+    TRACK,
+    COLOR_DEPTH,
+    DURATION,
+    ID,
+    PARENT,
+    TIMESTAMP,
+    URI,
+    DLNA_PROFILE,
+    GENRE
+}
+
 /**
  * Persistent storage of media objects
  *
@@ -131,12 +157,15 @@ public class Rygel.MediaExport.MediaCache : Object {
     "DELETE FROM Object WHERE upnp_id IN " +
         "(SELECT descendant FROM closure WHERE ancestor = ?)";
 
+    private const string ALL_DETAILS_STRING =
+    "o.type_fk, o.title, m.size, m.mime_type, m.width, " +
+    "m.height, m.class, m.author, m.album, m.date, m.bitrate, " +
+    "m.sample_freq, m.bits_per_sample, m.channels, m.track, " +
+    "m.color_depth, m.duration, o.upnp_id, o.parent, o.timestamp, " +
+    "o.uri, m.dlna_profile, m.genre ";
+
     private const string GET_OBJECT_WITH_PATH =
-    "SELECT DISTINCT o.type_fk, o.title, m.size, m.mime_type, m.width, " +
-            "m.height, m.class, m.author, m.album, m.date, m.bitrate, " +
-            "m.sample_freq, m.bits_per_sample, m.channels, m.track, " +
-            "m.color_depth, m.duration, o.parent, o.upnp_id, o.timestamp, " +
-            "o.uri, m.dlna_profile, m.genre " +
+    "SELECT DISTINCT " + ALL_DETAILS_STRING +
     "FROM Object o " +
         "JOIN Closure c ON (o.upnp_id = c.ancestor) " +
         "LEFT OUTER JOIN meta_data m ON (o.upnp_id = m.object_fk) " +
@@ -153,11 +182,7 @@ public class Rygel.MediaExport.MediaCache : Object {
      *   - and after that alphabetically
      */
     private const string GET_CHILDREN_STRING =
-    "SELECT o.type_fk, o.title, m.size, m.mime_type, " +
-            "m.width, m.height, m.class, m.author, m.album, " +
-            "m.date, m.bitrate, m.sample_freq, m.bits_per_sample, " +
-            "m.channels, m.track, m.color_depth, m.duration, " +
-            "o.upnp_id, o.parent, o.timestamp, o.uri, m.dlna_profile, m.genre " +
+    "SELECT " + ALL_DETAILS_STRING +
     "FROM Object o LEFT OUTER JOIN meta_data m " +
         "ON o.upnp_id = m.object_fk " +
     "WHERE o.parent = ? " +
@@ -169,11 +194,7 @@ public class Rygel.MediaExport.MediaCache : Object {
 
     // The uris are joined in to be able to filter by "ref"
     private const string GET_OBJECTS_BY_FILTER_STRING =
-    "SELECT DISTINCT o.type_fk, o.title, m.size, m.mime_type, " +
-            "m.width, m.height, m.class, m.author, m.album, " +
-            "m.date, m.bitrate, m.sample_freq, m.bits_per_sample, " +
-            "m.channels, m.track, m.color_depth, m.duration, " +
-            "o.upnp_id, o.parent, o.timestamp, o.uri, m.dlna_profile, m.genre " +
+    "SELECT DISTINCT " + ALL_DETAILS_STRING +
     "FROM Object o " +
         "JOIN Closure c ON o.upnp_id = c.descendant AND c.ancestor = ? " +
         "LEFT OUTER JOIN meta_data m " +
@@ -249,9 +270,10 @@ public class Rygel.MediaExport.MediaCache : Object {
 
         Database.RowCallback cb = (statement) => {
             var parent_container = parent as MediaContainer;
-            var object = get_object_from_statement (parent_container,
-                                                    statement.column_text (18),
-                                                    statement);
+            var object = get_object_from_statement (
+                                        parent_container,
+                                        statement.column_text (DetailColumn.ID),
+                                        statement);
             object.parent_ref = parent_container;
             parent = object;
 
@@ -332,7 +354,7 @@ public class Rygel.MediaExport.MediaCache : Object {
                                 (int64) offset,
                                 (int64) max_count };
         Database.RowCallback callback = (statement) => {
-            var child_id = statement.column_text (17);
+            var child_id = statement.column_text (DetailColumn.ID);
             children.add (get_object_from_statement (parent,
                                                      child_id,
                                                      statement));
@@ -447,8 +469,8 @@ public class Rygel.MediaExport.MediaCache : Object {
         debug ("Parameters to bind: %u", args.n_values);
 
         Database.RowCallback callback = (statement) => {
-            var child_id = statement.column_text (17);
-            var parent_id = statement.column_text (18);
+            var child_id = statement.column_text (DetailColumn.ID);
+            var parent_id = statement.column_text (DetailColumn.PARENT);
             try {
                 if (parent == null || parent_id != parent.id) {
                     parent = new NullContainer ();
@@ -622,27 +644,29 @@ public class Rygel.MediaExport.MediaCache : Object {
                                                     string          object_id,
                                                     Statement       statement) {
         MediaObject object = null;
-        switch (statement.column_int (0)) {
+        switch (statement.column_int (DetailColumn.TYPE)) {
             case 0:
                 // this is a container
                 object = factory.get_container (this,
                                                 object_id,
-                                                statement.column_text (1),
+                                                statement.column_text (
+                                                    DetailColumn.TITLE),
                                                 0);
 
                 var container = object as MediaContainer;
-                var uri = statement.column_text (20);
+                var uri = statement.column_text (DetailColumn.URI);
                 if (uri != null) {
                     container.set_uri (uri);
                 }
                 break;
             case 1:
                 // this is an item
-                var upnp_class = statement.column_text (6);
+                var upnp_class = statement.column_text (DetailColumn.CLASS);
                 object = factory.get_item (this,
                                            parent,
                                            object_id,
-                                           statement.column_text (1),
+                                           statement.column_text (
+                                               DetailColumn.TITLE),
                                            upnp_class);
                 fill_item (statement, object as MediaItem);
 
@@ -650,7 +674,7 @@ public class Rygel.MediaExport.MediaCache : Object {
                     (object as MediaItem).lookup_album_art ();
                 }
 
-                var uri = statement.column_text (20);
+                var uri = statement.column_text (DetailColumn.URI);
                 if (uri != null) {
                     (object as MediaItem).add_uri (uri, null);
                 }
@@ -660,32 +684,34 @@ public class Rygel.MediaExport.MediaCache : Object {
         }
 
         if (object != null) {
-            object.modified = statement.column_int64 (19);
+            object.modified = statement.column_int64 (DetailColumn.TIMESTAMP);
         }
 
         return object;
     }
 
     private void fill_item (Statement statement, MediaItem item) {
-        item.author = statement.column_text (7);
-        item.album = statement.column_text (8);
-        item.date = statement.column_text (9);
-        item.mime_type = statement.column_text (3);
-        item.duration = (long) statement.column_int64 (16);
-
-        item.size = (long) statement.column_int64 (2);
-        item.bitrate = statement.column_int (10);
-
-        item.sample_freq = statement.column_int (11);
-        item.bits_per_sample = statement.column_int (12);
-        item.n_audio_channels = statement.column_int (13);
-        item.track_number = statement.column_int (14);
-
-        item.width = statement.column_int (4);
-        item.height = statement.column_int (5);
-        item.color_depth = statement.column_int (15);
-        item.dlna_profile = statement.column_text (21);
-        item.genre = statement.column_text (22);
+        item.author = statement.column_text (DetailColumn.AUTHOR);
+        item.album = statement.column_text (DetailColumn.ALBUM);
+        item.date = statement.column_text (DetailColumn.DATE);
+        item.mime_type = statement.column_text (DetailColumn.MIME_TYPE);
+        item.duration = (long) statement.column_int64 (DetailColumn.DURATION);
+
+        item.size = (long) statement.column_int64 (DetailColumn.SIZE);
+        item.bitrate = statement.column_int (DetailColumn.BITRATE);
+
+        item.sample_freq = statement.column_int (DetailColumn.SAMPLE_FREQ);
+        item.bits_per_sample = statement.column_int (
+                                        DetailColumn.BITS_PER_SAMPLE);
+        item.n_audio_channels = statement.column_int (
+                                        DetailColumn.CHANNELS);
+        item.track_number = statement.column_int (DetailColumn.TRACK);
+
+        item.width = statement.column_int (DetailColumn.WIDTH);
+        item.height = statement.column_int (DetailColumn.HEIGHT);
+        item.color_depth = statement.column_int (DetailColumn.COLOR_DEPTH);
+        item.dlna_profile = statement.column_text (DetailColumn.DLNA_PROFILE);
+        item.genre = statement.column_text (DetailColumn.GENRE);
     }
 
     public ArrayList<string> get_child_ids (string container_id)