Half of having choices of music and a player of it (not finished)

OpenRA.Game/GameRules/MusicInfo.cs

@@ -0,0 +1,50 @@
+
+using System;
+
+using System.Collections.Generic;
+using OpenRA.FileFormats;
+
+namespace OpenRA.GameRules
+{
+	public class MusicInfo
+	{
+		public readonly Lazy<Dictionary<string, MusicPool>> Pools;
+		public readonly string[] Music = { };
+
+		public MusicInfo( MiniYaml y )
+		{
+			FieldLoader.Load(this, y);
+
+			Pools = Lazy.New(() =>
+				new Dictionary<string, MusicPool>
+				{
+					{ "Music", new MusicPool(Music) },
+				});
+		}
+	}
+	
+	public class MusicPool
+	{
+		readonly string[] clips;
+		readonly List<string> liveclips = new List<string>();
+
+		public MusicPool(params string[] clips)
+		{
+			this.clips = clips;
+		}
+
+		public string GetNext()
+		{
+			if (liveclips.Count == 0)
+				liveclips.AddRange(clips);
+
+			if (liveclips.Count == 0)
+				return null;		/* avoid crashing if there's no clips at all */
+
+			var i = Game.CosmeticRandom.Next(liveclips.Count);
+			var s = liveclips[i];
+			liveclips.RemoveAt(i);
+			return s;
+		}
+	}
+}

OpenRA.Game/GameRules/Rules.cs

@@ -33,6 +33,7 @@ namespace OpenRA
 		public static Dictionary<string, ActorInfo> Info;
 		public static Dictionary<string, WeaponInfo> Weapons;
 		public static Dictionary<string, VoiceInfo> Voices;
+		public static Dictionary<string, MusicInfo> Music;
 		public static Dictionary<TerrainType, TerrainCost> TerrainTypes;
 
 		public static void LoadRules(Manifest m)
@@ -44,6 +45,7 @@ namespace OpenRA
 			Info = LoadYamlRules(m.Rules, (k, y) => new ActorInfo(k.Key.ToLowerInvariant(), k.Value, y));
 			Weapons = LoadYamlRules(m.Weapons, (k, _) => new WeaponInfo(k.Key.ToLowerInvariant(), k.Value));
 			Voices = LoadYamlRules(m.Voices, (k, _) => new VoiceInfo(k.Value));
+			Music = LoadYamlRules(m.Music, (k, _) => new MusicInfo(k.Value));
 			TerrainTypes = LoadYamlRules(m.Terrain, (k, _) => new TerrainCost(k.Value))
 				.ToDictionary(kv => (TerrainType)Enum.Parse(typeof(TerrainType), kv.Key, true), kv => kv.Value);