Fix SpecialItem.getRandomItem

src/de/steamwar/misslewars/items/SpecialItem.java

@@ -40,7 +40,8 @@ import java.util.Random;
 public abstract class SpecialItem {
 
 	private static final Random random = new Random();
-	private static boolean lastItemWasSupportItem = false;
+	private static long missileCount = 0;
+	private static long supportCount = 0;
 
 	private static List<SpecialItem> supportItems = new ArrayList<>();
 	private static List<SpecialItem> missileItems = new ArrayList<>();
@@ -110,11 +111,21 @@ public abstract class SpecialItem {
 	}
 
 	public static ItemStack getRandomItem() {
-		if (!lastItemWasSupportItem && random.nextDouble() > Config.MissileChance) {
-			lastItemWasSupportItem = true;
-			return supportItems.get(random.nextInt(supportItems.size())).getItem();
+		double missile = missileCount * Config.MissileChance;
+		double support = supportCount;
+		double missileChance;
+		if (missile == 0 && support == 0) {
+			missileChance = 0.5;
+		} else {
+			missileChance = support / (support + missile);
+		}
+		
+		if (random.nextDouble() > missileChance) {
+			supportCount++;
+			return supportItems.get(random.nextInt(supportItems.size())).getItem();
+		} else {
+			missileCount++;
+			return missileItems.get(random.nextInt(missileItems.size())).getItem();
 		}
-		lastItemWasSupportItem = false;
-		return missileItems.get(random.nextInt(missileItems.size())).getItem();
 	}
 }