Validate tower doesn't block barrack path (closes #60)

Assets/Scripts/Logic/Data/GameTeam.cs

@@ -17,10 +17,15 @@ public class GameTeam {
 
 	public Castle Castle { get; }
 
+	public IEnumerable<Tower> Towers => Overview.World.GetTileObjectsOfType<Tower>()
+		.Where(t => t.OwnerColor == TeamColor);
+
+	public IEnumerable<Unit> Units => Overview.World.Units
+		.Where(t => t.Owner == this);
+
 	public int Money { get; private set; } = 500; //TODO don't use a hardcoded value
 
-	public int PresentTowerCount => Overview.World.GetTileObjectsOfType<Tower>()
-		.Count(tower => tower.OwnerColor == TeamColor);
+	public int PresentTowerCount => Towers.Count();
 
 	public int MoneySpent { get; private set; }
 

Assets/Scripts/Logic/Handler/ManageTowerHandler.cs

@@ -28,11 +28,14 @@ public class ManageTowerHandler : BaseHandler {
 
 		ICollection<TilePosition> blockedTiles = new List<TilePosition>();
 		blockedTiles.Add(command.Position);
-		foreach (Unit unit in world.Units) {
-			TilePosition from = unit.TilePosition;
-			TilePosition to = overview.GetEnemyTeam(unit.Owner).Castle.Position;
-			if (!world.Navigation.IsPositionReachable(from, to, blockedTiles)) {
-				return BuildTowerCommand.CommandResult.LeavesNoPathForUnit;
+
+		foreach (GameTeam team in overview.Teams) {
+			TilePosition to = overview.GetEnemyTeam(team).Castle.Position;
+			foreach (TilePosition from in team.Barracks.Select(b => b.Position)
+				.Concat(team.Units.Select(u => u.TilePosition))) {
+				if (!world.Navigation.IsPositionReachable(from, to, blockedTiles)) {
+					return BuildTowerCommand.CommandResult.LeavesNoPathForUnit;
+				}
 			}
 		}