mod manifest loading

OpenRa.FileFormats/Session.cs

@@ -31,7 +31,32 @@ namespace OpenRa.FileFormats
 		{
 			public string Map = "scm12ea.ini";
 			public string[] Packages = {};	// filename:sha1 pairs.
+			public string[] Mods = { "ra" };	// mod names
 			public int OrderLatency = 3;
 		}
 	}
+
+	public class Manifest
+	{
+		public readonly string[] Packages = { };
+		public readonly string[] LegacyRules = { };
+		public readonly string[] Rules = { };
+		public readonly string[] Sequences = { };
+		public readonly string[] Assemblies = { };
+
+		public Manifest(string[] mods)
+		{
+			var yaml = mods
+				.Select(m => MiniYaml.FromFile("mods/" + m + "/mod.yaml"))
+				.Aggregate(MiniYaml.Merge);
+
+			Packages = YamlList(yaml, "Packages");
+			LegacyRules = YamlList(yaml, "LegacyRules");
+			Rules = YamlList(yaml, "Rules");
+			Sequences = YamlList(yaml, "Sequences");
+			Assemblies = YamlList(yaml, "Assemblies");
+		}
+
+		static string[] YamlList(Dictionary<string, MiniYaml> ys, string key) { return ys[key].Nodes.Keys.ToArray(); }
+	}
 }