the whole game

src/util/WeighedRandom.h

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+#ifndef UTIL__WeighedRandom_H__
+#define UTIL__WeighedRandom_H__
+
+//package util;
+
+#include "Random.h"
+
+class WeighedRandom
+{
+public:
+    class WeighedRandomItem {
+	public:
+        int randomWeight;
+
+		WeighedRandomItem()
+		:	randomWeight(-128)
+		{}
+
+        WeighedRandomItem(int randomWeight)
+		:	randomWeight(randomWeight)
+		{}
+        
+        bool isValid() {
+            return randomWeight >= 0;
+        }
+    };
+
+	template <typename T>
+    static int getTotalWeight(const T& items) {
+        int totalWeight = 0;
+
+        for (typename T::const_iterator it = items.begin(); it != items.end(); ++it)
+            totalWeight += it->randomWeight;
+
+        return totalWeight;
+    }
+
+    template <typename T>
+    static const WeighedRandomItem* getRandomItem(Random* random, const T& items, int totalWeight) {
+        int selection = random->nextInt(totalWeight);
+        for (typename T::const_iterator it = items.begin(); it != items.end(); ++it) {
+            selection -= it->randomWeight;
+            if (selection < 0) {
+                return &(*it);
+            }
+        }
+        return NULL;
+    }
+    template<typename T>
+    static const WeighedRandomItem* getRandomItem(Random* random, const T& items) {
+        return getRandomItem(random, items, getTotalWeight(items));
+    }
+
+	template <typename T>
+    static int getRandomItemIndex(Random* random, const T& items, int totalWeight) {
+        int selection = random->nextInt(totalWeight);
+        for (unsigned int i = 0; i < items.size(); ++i) {
+			selection -= items[i].randomWeight;
+            if (selection < 0) {
+                return i;
+            }
+        }
+        return -1;
+    }
+    template<typename T>
+    static int getRandomItemIndex(Random* random, const T& items) {
+        return getRandomItemIndex(random, items, getTotalWeight(items));
+    }
+
+//     static int getTotalWeight(WeighedRandomItem items) {
+//         int totalWeight = 0;
+//
+//         for (unsigned int i = 0; i < items.size(); ++i) {
+//             WeighedRandomItem& item = items[i];
+//             totalWeight += item.randomWeight;
+//         }
+//         return totalWeight;
+//     }
+
+//     static WeighedRandomItem getRandomItem(Random* random, WeighedRandomItem[] items, int totalWeight) {
+//
+//         if (totalWeight <= 0) {
+//             throw /*new*/ IllegalArgumentException();
+//         }
+//
+//         int selection = random->nextInt(totalWeight);
+//         for (unsigned int i = 0; i < items.size(); ++i) {
+//             WeighedRandomItem& item = items[i];
+//         //for (WeighedRandomItem item : items) {
+//             selection -= item.randomWeight;
+//             if (selection < 0) {
+//                 return item;
+//             }
+//         }
+//         return NULL;
+//     }
+
+//     static WeighedRandomItem getRandomItem(Random* random, WeighedRandomItem[] items) {
+//         return getRandomItem(random, items, getTotalWeight(items));
+//     }
+};
+
+#endif /*UTIL__WeighedRandom_H__*/