Move random methods to random util class, fix footer

src/main/java/wtf/beatrice/hidekobot/util/RandomUtil.java

@@ -1,9 +1,19 @@
 package wtf.beatrice.hidekobot.util;
 
+import org.random.util.RandomOrgRandom;
 import wtf.beatrice.hidekobot.Cache;
+import wtf.beatrice.hidekobot.datasources.ConfigurationEntry;
+
+import java.security.SecureRandom;
+import java.util.Random;
 
 public class RandomUtil
 {
+
+    // the Random instance that we should always use when looking for an RNG based thing.
+    // the seed is updated periodically, if the random.org integration is enabled.
+    private static Random randomInstance = new SecureRandom();
+
     /**
      * Returns a random integer picked in a range.
      *
@@ -26,9 +36,43 @@ public class RandomUtil
         int difference = (max - min) + 1;
 
         // find a number between 0 and our range (eg. 5 -> 8 = 0 -> 3)
-        int randomTemp = Cache.getRandom().nextInt(difference);
+        int randomTemp = getRandom().nextInt(difference);
 
         // add the minimum value, so we are sure to be in the original range (0->5, 1->6, 2->7, 3->8)
         return randomTemp + min;
     }
+
+
+    public static Random getRandom() {
+        return randomInstance;
+    }
+
+    public static void initRandomOrg()
+    {
+        /* we use the random.org instance to generate 160 random bytes.
+        then, we're feeding those 160 bytes as a seed for a SecureRandom.
+
+        this is preferred to calling the RandomOrgRandom directly every time,
+        because it has to query the api and (1) takes a long time, especially with big
+        dice rolls, and (2) you'd run in the limits extremely quickly if the bot
+        was run publicly for everyone to use.
+         */
+        String apiKey = Cache.getRandomOrgApiKey();
+
+        RandomOrgRandom randomOrg = new RandomOrgRandom(apiKey);
+        byte[] randomBytes = new byte[160];
+        randomOrg.nextBytes(randomBytes);
+
+        randomInstance = new SecureRandom(randomBytes);
+    }
+
+
+    public static boolean isRandomOrgKeyValid()
+    {
+        String apiKey = Cache.getRandomOrgApiKey();
+
+        return apiKey != null &&
+                !apiKey.isEmpty() &&
+                !apiKey.equals(ConfigurationEntry.RANDOM_ORG_API_KEY.getDefaultValue());
+    }
 }