Resolve "As a QR-scanning connoisseur , I want to unlock stickers after scanning a QR code to feel a sense of reward."

Closes #73 (closed)

src/main/java/team5/smartTowns/rewards/RewardsController.java

+package team5.smartTowns.rewards;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.servlet.ModelAndView;
+import team5.smartTowns.users.User;
+import team5.smartTowns.users.UserRepository;
+
+import java.util.List;
+import java.util.Map;
+
+@Controller
+public class RewardsController {
+
+    @Autowired
+    RewardsRepository rewardsRepository;
+
+    @Autowired
+    UserRepository userRepository;
+
+    @GetMapping("/packInfo/{userID}/{packID}")
+    public ModelAndView getPackInfo(@PathVariable int userID, @PathVariable int packID) {
+        ModelAndView mav = new ModelAndView("users/userFrags :: stickersBox");
+        List<Sticker> allStickers = rewardsRepository.getAllStickersFromPack(packID);
+        Map<Long, Boolean> userStickers = userRepository.getStickers(userID);
+
+        for (Long stickerID : userStickers.keySet()) { //Finds and updates visibility of stickers based on what the user has
+            allStickers.stream()
+                    .filter(sticker -> sticker.getId()==stickerID)
+                    .findFirst().ifPresent(sticker -> sticker.setVisibility(userStickers.get(stickerID)));
+        }
+
+        mav.addObject("stickers", allStickers);
+
+        return mav;
+    }
+
+
+}