[rygel] media-export: Implement fallback to slow search

[Zeeshan Ali Khattak <zeeshanak src gnome org>]

commit 7e04310ebda8f1a726e420fa33788abb273287b8
Author: Jens Georg <mail jensge org>
Date:   Fri Jun 25 19:14:40 2010 +0200

    media-export: Implement fallback to slow search

 .../rygel-media-export-db-container.vala           |   16 +++++++++++++-
 .../rygel-media-export-media-cache.vala            |    4 +-
 .../rygel-media-export-query-container.vala        |   23 ++++++++++++++-----
 3 files changed, 34 insertions(+), 9 deletions(-)
---
diff --git a/src/plugins/media-export/rygel-media-export-db-container.vala b/src/plugins/media-export/rygel-media-export-db-container.vala
index 55ae2f5..68bff75 100644
--- a/src/plugins/media-export/rygel-media-export-db-container.vala
+++ b/src/plugins/media-export/rygel-media-export-db-container.vala
@@ -72,17 +72,31 @@ public class Rygel.MediaExport.DBContainer : MediaContainer {
                                         out uint         total_matches,
                                         Cancellable?     cancellable)
                                         throws GLib.Error {
+        Gee.List<MediaObject> children = null;
+
         var max_objects = max_count;
         if (max_objects == 0) {
             max_objects = -1;
         }
 
-        var children = this.media_db.get_objects_by_search_expression (
+        try {
+            children = this.media_db.get_objects_by_search_expression (
                                         expression,
                                         this.id,
                                         offset,
                                         max_objects,
                                         out total_matches);
+        } catch (MediaDBError error) {
+            if (error is MediaDBError.UNSUPPORTED_SEARCH) {
+                children = yield base.search (expression,
+                                              offset,
+                                              max_count,
+                                              out total_matches,
+                                              cancellable);
+            } else {
+                throw error;
+            }
+        }
 
         return children;
     }
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 c649d48..5e10d46 100644
--- a/src/plugins/media-export/rygel-media-export-media-cache.vala
+++ b/src/plugins/media-export/rygel-media-export-media-cache.vala
@@ -29,7 +29,7 @@ public errordomain Rygel.MediaDBError {
     SQLITE_ERROR,
     GENERAL_ERROR,
     INVALID_TYPE,
-    UNSUPPORTED
+    UNSUPPORTED_SEARCH
 }
 
 public enum Rygel.MediaDBObjectType {
@@ -781,7 +781,7 @@ public class Rygel.MediaExport.MediaCache : Object {
             default:
                 var message = "Unsupported column %s".printf (operand);
 
-                throw new MediaDBError.UNSUPPORTED (message);
+                throw new MediaDBError.UNSUPPORTED_SEARCH (message);
         }
 
         return column;
diff --git a/src/plugins/media-export/rygel-media-export-query-container.vala b/src/plugins/media-export/rygel-media-export-query-container.vala
index 02cd3df..e009e82 100644
--- a/src/plugins/media-export/rygel-media-export-query-container.vala
+++ b/src/plugins/media-export/rygel-media-export-query-container.vala
@@ -153,6 +153,8 @@ internal class Rygel.MediaExport.QueryContainer : DBContainer {
                                         out uint         total_matches,
                                         Cancellable?     cancellable)
                                         throws GLib.Error {
+        Gee.List<MediaObject> children = null;
+
         var combined_expression = new LogicalExpression ();
         combined_expression.operand1 = this.expression;
         combined_expression.op = LogicalOperator.AND;
@@ -163,12 +165,21 @@ internal class Rygel.MediaExport.QueryContainer : DBContainer {
             max_objects = -1;
         }
 
-        var children = this.media_db.get_objects_by_search_expression (
-                                        combined_expression,
-                                        "0",
-                                        offset,
-                                        max_objects,
-                                        out total_matches);
+        try {
+            children = this.media_db.get_objects_by_search_expression (
+                                            combined_expression,
+                                            "0",
+                                            offset,
+                                            max_objects,
+                                            out total_matches);
+        } catch (MediaDBError error) {
+            if (error is MediaDBError.UNSUPPORTED_SEARCH) {
+                children = new ArrayList<MediaObject> ();
+                total_matches = 0;
+            } else {
+                throw error;
+            }
+        }
 
         return children;
     }