Per-player unit production. Also, fixed an interesting bug in Sequence.

OpenRa.Game/Player.cs

@@ -1,3 +1,5 @@
+using System;
+using System.Collections.Generic;
 
 namespace OpenRa.Game
 {
@@ -19,5 +21,87 @@ namespace OpenRa.Game
 		{
 			return 0.5f;		/* todo: work this out the same way as RA */
 		}
+
+		public void GiveCash( int num )
+		{
+			// TODO: increase cash
+		}
+
+		public bool TakeCash( int num )
+		{
+			// TODO: decrease cash.
+			// returns: if enough cash was available, true
+			return true;
+		}
+
+		public void Tick()
+		{
+			foreach( var p in production )
+			{
+				if( p.Value != null )
+					p.Value.Tick( this );
+			}
+		}
+
+		// Key: Production category. Categories are: building, infantry, vehicle, boat, plane (and one per super, if they're done in here)
+		readonly Dictionary<string, ProductionItem> production = new Dictionary<string, ProductionItem>();
+
+		public void ProductionInit( string category )
+		{
+			production.Add( category, null );
+		}
+
+		public ProductionItem Producing( string category )
+		{
+			return production[ category ];
+		}
+
+		public void CancelProduction( string category )
+		{
+			var item = production[ category ];
+			if( item == null ) return;
+			GiveCash( item.TotalCost - item.RemainingCost ); // refund what's been paid so far.
+			production[ category ] = null;
+		}
+
+		public void BeginProduction( string group, ProductionItem item )
+		{
+			if( production[ group ] != null ) return;
+			production[ group ] = item;
+		}
+	}
+
+	class ProductionItem
+	{
+		public readonly string Item;
+
+		public readonly int TotalTime;
+		public readonly int TotalCost;
+		public int RemainingTime { get; private set; }
+		public int RemainingCost { get; private set; }
+
+		public bool Paused = false, Done = false;
+
+		public ProductionItem( string item, int time, int cost )
+		{
+			Item = item;
+			RemainingTime = TotalTime = time;
+			RemainingCost = TotalCost = cost;
+		}
+
+		public void Tick( Player player )
+		{
+			if( Paused || Done ) return;
+
+			var costThisFrame = RemainingCost / RemainingTime;
+			if( costThisFrame == 0 && !player.TakeCash( costThisFrame ) ) return;
+
+			RemainingCost -= costThisFrame;
+			RemainingTime -= 1;
+			if( RemainingTime > 0 ) return;
+
+			// item finished; do whatever needs done.
+			Done = true;
+		}
 	}
 }