compliting loadProducts() and processFile() functions.

src/main/java/ReportGenerator.java

@@ -1,4 +1,8 @@
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
 import java.util.List;
+import java.util.Scanner;
 
 public class ReportGenerator {
 
@@ -8,7 +12,7 @@ public class ReportGenerator {
     private double totalFinalCost;
     private int totalQuantity;
     private double totalDiscountValue;
-    private int totalInvalidLines;
+    private int InvalidLines;
 
     public ReportGenerator(String ordersFilePath, List<Product> productList) {
         this.ordersFilePath = ordersFilePath;
@@ -17,44 +21,63 @@ public class ReportGenerator {
 
     public void processFile()
     {
-        // TODO:
-        // 1. Open the order details CSV file
-        // 2. Read the file line by line
-        // 3. Split each line using comma delimiter
-        //      (each line is guaranteed to contain exactly two commas)
-        // 4. Each line contains exactly 3 values in the format:
-        //      [productId],[quantity],[discountPercent]
-        // 5. Attempt to convert values:
-        //      - productId -> int
-        //      - quantity -> int
-        //      - discountPercent -> int
-        //    NOTE:
-        //      - quantity and discountPercent may contain invalid characters
-        //        (e.g., letters instead of numbers).
-        //      - If parsing any value fails (NumberFormatException),
-        //        the entire line must be considered invalid.
-        //      - Use try-catch blocks and exception handling to safely
-        //        handle parsing and validation errors without stopping
-        //        the processing of the remaining lines.
-        // 6. Validate parsed values:
-        //      - productId must be greater than 0
-        //      - quantity must be greater than 0
-        //      - discountPercent must be between 0 and 99 inclusive
-        // 7. Look for a Product in productList that matches productId
-        // 8. If no Product with that ID exists in the catalog,
-        //      the entire line is considered invalid
-        // 9. If all values are valid and the product exists, calculate:
-        //      subtotal = quantity * product price
-        //      discountValue = subtotal * discountPercent / 100
-        //      finalCost = subtotal - discountValue
-        // 10. Update report totals:
-        //      - totalQuantity += quantity
-        //      - totalFinalCost += finalCost
-        //      - totalDiscountValue += discountValue
-        // 11. If any parsing error, validation failure, or missing product occurs:
-        //      - increment totalInvalidLines
-        //      - skip the line and continue processing the next line
-        // 12. Close all file resources
+        //opening and doing the math
+        try {
+            File source = new File(ordersFilePath);
+            Scanner scanner = new Scanner(source);
+            //
+            while (scanner.hasNextLine()) {
+                int productId;
+                int count;
+                int discountPercentage;
+                String line = scanner.nextLine();
+                String[] parts  = line.split(",");
+                try {
+                    productId = Integer.parseInt(parts[0].trim());
+                    if (productId < 1 || productId > productList.size()) {
+                        InvalidLines++;
+                        continue;
+                    }
+
+                } catch (NumberFormatException e) {
+                    InvalidLines++;
+                    continue;
+                }
+                try {
+                    count = Integer.parseInt(parts[1].trim());
+                    if(count < 1) {
+                        InvalidLines++;
+                        continue;
+                    }
+                } catch (NumberFormatException e) {
+                    InvalidLines++;
+                    continue;
+                }
+                try {
+                    discountPercentage = Integer.parseInt(parts[2].trim());
+                    if (discountPercentage < 0 || discountPercentage > 99) {
+                        InvalidLines++;
+                        continue;
+                    }
+                } catch (NumberFormatException e) {
+                    InvalidLines++;
+                    continue;
+                }
+
+                //computing the results
+                double cost = count * productList.get(productId - 1).getPrice();
+                double discount = count * productList.get(productId - 1).getPrice() * discountPercentage / 100;
+                totalFinalCost += cost - discount;
+                totalDiscountValue += discount;
+                totalQuantity += count;
+
+            }
+            scanner.close();
+        } catch (FileNotFoundException e) {
+            System.out.println("File not found.");
+        } catch (IOException e) {
+            System.out.println(e.getMessage());
+        }
     }
 
     public void saveReport()