[gnome-games/wip/aplazas/781334-refactor-game-sources: 2/6] steam: Add SteamUriIterator

[Adrien Plazas <aplazas src gnome org>]

commit 196d78699d53a2b909973f10b4876c6026f762f4
Author: Adrien Plazas <kekun plazas laposte net>
Date:   Sat May 6 11:22:48 2017 +0200

    steam: Add SteamUriIterator
    
    This will be used to iterate through the available Steam game resources.

 plugins/steam/src/Makefile.am             |    1 +
 plugins/steam/src/steam-uri-iterator.vala |   58 +++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+), 0 deletions(-)
---
diff --git a/plugins/steam/src/Makefile.am b/plugins/steam/src/Makefile.am
index 29b1556..172531d 100644
--- a/plugins/steam/src/Makefile.am
+++ b/plugins/steam/src/Makefile.am
@@ -13,6 +13,7 @@ libgames_steam_plugin_la_SOURCES = \
        steam-plugin.vala \
        steam-registry.vala \
        steam-title.vala \
+       steam-uri-iterator.vala \
        $(NULL)
 
 libgames_steam_plugin_la_VALAFLAGS = \
diff --git a/plugins/steam/src/steam-uri-iterator.vala b/plugins/steam/src/steam-uri-iterator.vala
new file mode 100644
index 0000000..c148bfb
--- /dev/null
+++ b/plugins/steam/src/steam-uri-iterator.vala
@@ -0,0 +1,58 @@
+// This file is part of GNOME Games. License: GPL-3.0+.
+
+private class Games.SteamUriIterator : Object, UriIterator {
+       private string[] directories;
+       private int directory_index;
+       private Uri? uri;
+
+       internal SteamUriIterator (string[] directories) {
+               this.directories = directories;
+               directory_index = 0;
+               uri = null;
+       }
+
+       public new Uri? get () {
+               return uri;
+       }
+
+       public bool next () {
+               while (directory_index < directories.length) {
+                       if (try_next_for_directory (directories[directory_index]))
+                               return true;
+
+                       directory_index++;
+               }
+
+               return false;
+       }
+
+       private bool try_next_for_directory (string directory) {
+               try {
+                       if (next_for_directory (directory))
+                               return true;
+               }
+               catch (Error e) {
+                       debug (e.message);
+               }
+
+               uri = null;
+
+               return false;
+       }
+
+       private bool next_for_directory (string directory) throws Error {
+               var file = File.new_for_path (directory);
+
+               var enumerator = file.enumerate_children (FileAttribute.STANDARD_NAME, 0);
+
+               var info = enumerator.next_file ();
+               if (info == null)
+                       return false;
+
+               var filename = Path.build_filename (directory, info.get_name ());
+               var file_uri = Filename.to_uri (filename);
+               uri = new Uri (@"steam+$file_uri");
+
+               return true;
+       }
+}