Allows running tests using a seeded RNG.

Running the same game twice now works! There may be issues I haven't found with certain AI behaviors around mechanics I didn't use in my tests.


(cherry picked from commit 194b47c1ad61c8f1efb6bce8af2bb10d1fa8f6c3)

forge-ai/src/main/java/forge/ai/ComputerUtil.java

@@ -2216,7 +2216,10 @@ public class ComputerUtil {
                     }
                 return ComputerUtilCard.getBestAI(list);
             } else {
-                return Iterables.getFirst(votes.keySet(), null);
+        	// TODO: This is just picking randomly amongst already picked things. It should probably pick the worst instead.
+        	List<Object> a = Arrays.asList(votes.keySet().toArray());
+        	Collections.shuffle(a, MyRandom.getRandom());
+                return a.get(0);
             }
         case "Protection":
             if (votes.isEmpty()) {

forge-ai/src/main/java/forge/ai/ComputerUtilMana.java

@@ -134,7 +134,8 @@ public class ComputerUtilMana {
         Collections.sort(orderedCards, new Comparator<Card>() {
             @Override
             public int compare(final Card card1, final Card card2) {
-                return Integer.compare(manaCardMap.get(card1), manaCardMap.get(card2));
+        	int result = Integer.compare(manaCardMap.get(card1), manaCardMap.get(card2));
+                return result != 0 ? result : Float.compare(card1.getTimestamp(), card2.getTimestamp()); 
             }
         });
 
@@ -308,7 +309,7 @@ public class ComputerUtilMana {
         }
 
         // select which abilities may be used for each shard
-        Multimap<ManaCostShard, SpellAbility> sourcesForShards = ComputerUtilMana.groupAndOrderToPayShards(ai, manaAbilityMap, cost);
+        ListMultimap<ManaCostShard, SpellAbility> sourcesForShards = ComputerUtilMana.groupAndOrderToPayShards(ai, manaAbilityMap, cost);
 
         sortManaAbilities(sourcesForShards);
 
@@ -858,7 +859,6 @@ public class ComputerUtilMana {
         }
 
         AiController aic = ((PlayerControllerAi)ai.getController()).getAi();
-        int chanceToReserve = aic.getIntProperty(AiProps.RESERVE_MANA_FOR_MAIN2_CHANCE);
 
         PhaseType curPhase = ai.getGame().getPhaseHandler().getPhase();
 
@@ -877,7 +877,8 @@ public class ComputerUtilMana {
         // obey mana reservations for Main 2; otherwise, obey mana reservations depending on the "chance to reserve"
         // AI profile variable.
         if (sa.getSVar("LowPriorityAI").equals("")) {
-            if (chanceToReserve == 0 || MyRandom.getRandom().nextInt(100) >= chanceToReserve) {
+            float chanceToReserve = aic.getFloatProperty(AiProps.RESERVE_MANA_FOR_MAIN2_CHANCE);
+            if (MyRandom.getRandom().nextDouble() >= chanceToReserve) {
                 return false;
             }
         }
@@ -1005,7 +1006,7 @@ public class ComputerUtilMana {
      * @return a boolean.
      */
     private static String payMultipleMana(ManaCostBeingPaid testCost, String mana, final Player p) {
-        List<String> unused = new ArrayList<>(4);
+        List<String> unused = new ArrayList<String>(4);
         for (String manaPart : TextUtil.split(mana, ' ')) {
             if (StringUtils.isNumeric(manaPart)) {
                 for (int i = Integer.parseInt(manaPart); i > 0; i--) {

forge-core/src/main/java/forge/util/MyRandom.java

@@ -34,22 +34,27 @@ public class MyRandom {
     private static Random random = new SecureRandom();
 
     /**
-     * <p>
+     * Changes into a non-CSPRNG, which can be seeded for use in tests/repeatable experiments.
-     * percentTrue.<br>
-     * If percent is like 30, then 30% of the time it will be true.
-     * </p>
-     * 
-     * @param percent
-     *            a int.
-     * @return a boolean.
      */
-    public static boolean percentTrue(final int percent) {
+    public static void setSeed(int seed) {
-        return percent > MyRandom.getRandom().nextInt(100);
+	System.out.println("Setting the RNG seed to: " + seed);
+	random = new Random(seed);
+    }
+    
+    /**
+     * Returns True with Percent probability.
+     * 
+     * TODO: My guess is no one is passing in a number scaled to 100. This API should probably be cut.
+     */
+    public static boolean percentTrue(final long percent) {
+        return percent > MyRandom.getRandom().nextDouble() * 100;
     }
 
     /**
      * Gets the random.
      * 
+     * TODO: Make this private, and instead add a robust set of APIs here.
+     * 
      * @return the random
      */
     public static Random getRandom() {
@@ -60,7 +65,7 @@ public class MyRandom {
         int[] groups = new int[numGroups];
         
         for (int i = 0; i < value; i++) {
-            groups[random.nextInt(numGroups)]++;
+            groups[MyRandom.getRandom().nextInt(numGroups)]++;
         }
 
         return groups;

forge-gui-desktop/src/main/java/forge/view/SimulateMatch.java

@@ -22,6 +22,7 @@ import forge.game.player.RegisteredPlayer;
 import forge.model.FModel;
 import forge.player.GamePlayerUtil;
 import forge.util.Lang;
+import forge.util.MyRandom;
 
 public class SimulateMatch {
     public static void simulate(String[] args) {
@@ -55,6 +56,7 @@ public class SimulateMatch {
             }
             else {
                 System.err.println("Illegal parameter usage");
+                argumentHelp();
                 return;
             }
         }
@@ -78,6 +80,10 @@ public class SimulateMatch {
             type = GameType.valueOf(WordUtils.capitalize(params.get("f").get(0)));
         }
 
+        if (params.containsKey("s")) {
+            MyRandom.setSeed(Integer.parseInt(params.get("s").get(0)));
+        }
+        
         GameRules rules = new GameRules(type);
         rules.setAppliedVariants(EnumSet.of(type));
 
@@ -145,7 +151,7 @@ public class SimulateMatch {
     }
 
     private static void argumentHelp() {
-        System.out.println("Syntax: forge.exe sim -d <deck1[.dck]> ... <deckX[.dck]> -D [D] -n [N] -m [M] -t [T] -p [P] -f [F] -q");
+        System.out.println("Syntax: forge.exe sim -d <deck1[.dck]> ... <deckX[.dck]> -D [D] -n [N] -m [M] -t [T] -p [P] -f [F] -s [S] -q");
         System.out.println("\tsim - stands for simulation mode");
         System.out.println("\tdeck1 (or deck2,...,X) - constructed deck name or filename (has to be quoted when contains multiple words)");
         System.out.println("\tdeck is treated as file if it ends with a dot followed by three numbers or letters");
@@ -155,6 +161,7 @@ public class SimulateMatch {
         System.out.println("\tT - Type of tournament to run with all provided decks (Bracket, RoundRobin, Swiss)");
         System.out.println("\tP - Amount of players per match (used only with Tournaments, defaults to 2)");
         System.out.println("\tF - format of games, defaults to constructed");
+        System.out.println("\ts - Set the RNG seed. Use if you want to play the same game twice.");
         System.out.println("\tq - Quiet flag. Output just the game result, not the entire game log.");
     }
 
@@ -167,7 +174,6 @@ public class SimulateMatch {
         final Game g1 = mc.createGame();
         // will run match in the same thread
 
-        long startTime = System.currentTimeMillis();
         try {
             TimeLimitedCodeBlock.runWithTimeout(new Runnable() {
                 @Override

forge-gui-desktop/src/test/java/forge/ai/simulation/SimulationTestCase.java

@@ -29,12 +29,14 @@ import forge.item.IPaperCard;
 import forge.model.FModel;
 import forge.properties.ForgePreferences;
 import forge.properties.ForgePreferences.FPref;
+import forge.util.MyRandom;
 import junit.framework.TestCase;
 
 public class SimulationTestCase extends TestCase {
     private static boolean initialized = false;
 
     protected Game initAndCreateGame() {
+	MyRandom.setSeed(0); // Initialize the random seed to create predictable tests.
         List<RegisteredPlayer> players = Lists.newArrayList();
         Deck d1 = new Deck();
         players.add(new RegisteredPlayer(d1).setPlayer(new LobbyPlayerAi("p2", null)));