Endpoint to add lost money was added

src/main/java/ntnu/idatt2016/v233/SmartMat/controller/group/WasteController.java

@@ -92,4 +92,15 @@ public class WasteController {
         return wasteService.getLastMonth(groupId).map(ResponseEntity::ok).orElseGet(()->ResponseEntity.notFound().build());
     }
 
+    /**
+     * Retrieves the amount of money lost due to expired products in a specific group.
+     * The amount is calculated based on the total cost of the expired products.
+     *
+     * @param groupId the ID of the group to retrieve the lost money from
+     * @return a ResponseEntity with the lost money as a Double if found, or a ResponseEntity with status 404 if the group is not found
+     */
+    @GetMapping("/statistic/lostMoney/{groupId}")
+    public ResponseEntity<Double> getLostMoney(@PathVariable("groupId") long groupId){
+        return wasteService.getLostMoney(groupId).map(ResponseEntity::ok).orElseGet(()->ResponseEntity.notFound().build());
+    }
 }

src/main/java/ntnu/idatt2016/v233/SmartMat/service/group/WasteService.java

@@ -89,4 +89,15 @@ public class WasteService {
         Optional<Group> group = groupRepository.findByGroupId(groupId);
         return group.map(value -> StatisticUtil.getNumberOfWasteByLastMonth(wasteRepository.findByGroupId(value).get()));
     }
+
+    /**
+     * Retrieves the lost money in the last month for the group with the given ID.
+     *
+     * @param groupId the ID of the group to retrieve the lost money for
+     * @return an {@code Optional} containing the lost money if the group exists, or empty if it doesn't exist or there are no wastes in the last month
+     */
+    public Optional<Double> getLostMoney(long groupId) {
+        Optional<Group> group = groupRepository.findByGroupId(groupId);
+        return group.map(value -> StatisticUtil.getLostMoneyInLastMonth(wasteRepository.findByGroupId(value).get()));
+    }
 }

src/main/java/ntnu/idatt2016/v233/SmartMat/util/StatisticUtil.java

@@ -3,7 +3,9 @@ package ntnu.idatt2016.v233.SmartMat.util;
 import ntnu.idatt2016.v233.SmartMat.entity.Waste;
 
 import java.sql.Date;
+import java.sql.Timestamp;
 import java.time.LocalDate;
+import java.time.LocalDateTime;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -117,4 +119,37 @@ public class StatisticUtil {
         return sum;
     }
 
+    /**
+     * Calculates the total amount of money lost due to expired or discarded items in the last 30 days,
+     * based on the list of wastes passed as a parameter.
+     *
+     * @param wastes the list of wastes to be analyzed
+     * @return the total amount of money lost due to expired or discarded items in the last 30 days
+     */
+    public static double getLostMoneyInLastMonth(List<Waste> wastes){
+        List<Waste> wasteList = new ArrayList<>();
+        LocalDateTime time = LocalDateTime.now().minusDays(30);
+        for(Waste waste: wastes){
+            if(waste.getTimestamp().after(Timestamp.valueOf(time))){
+                wasteList.add(waste);
+            }
+        }
+        return lostMoney(wasteList);
+    }
+
+    /**
+     * Calculates the total amount of money lost due to expired or discarded items,
+     * based on the list of wastes passed as a parameter.
+     *
+     * @param wastes the list of wastes to be analyzed
+     * @return the total amount of money lost due to expired or discarded items
+     */
+    private static double lostMoney(List<Waste> wastes){
+        double sum = 0.0;
+        for(Waste waste: wastes){
+            sum += waste.getAmount()*waste.getBuyPrice();
+        }
+        return sum;
+    }
+
 }
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