Implement Generate Invoice

<UserStory> PAY001: Generate Invoice </UserStory>

<Changes>
    1. Added Utility.h to project configuration for supporting invoice generation utilities.
    2. Updated Invoice model to use string-based keys for parts mapping instead of integer keys.
    3. Implemented PaymentManagementService::generateInvoice to aggregate labour cost, parts cost, and apply discounts.
    4. Integrated invoice creation with Factory to instantiate Invoice objects and persist them into datastore.
    5. Enhanced Enums with PaymentMode::NOTSET to handle default invoice state.
</Changes>

<Test>

 Acceptance Criteria:
 1. Invoice auto-generates for each service booking once jobs are completed.
 2. Invoice shows a clear breakdown of charges including labour cost, parts cost, discount, and total amount.

 Precondition:
  1. Service booking exists with at least one service and required inventory items.
  2. Datastore is available for storing invoices.
  3. Payment mode and status enums are properly configured.

 Steps:
  1. Complete all jobs in a service booking.
    - Verify that PaymentManagementService::generateInvoice is triggered.
  2. Check datastore for newly created invoice.
    - Verify that invoice contains booking ID, labour cost, parts cost, discount, and total amount.
  3. Inspect invoice details.
    - Verify that breakdown of charges is accurate and discount is applied correctly.
  4. Confirm invoice status.
    - Verify that invoice is created with PaymentMode::NOTSET and PaymentStatus::PENDING.
</Test>

<Review>
Sreeja Reghukumar, please review
</Review>

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem.vcxproj

@@ -176,6 +176,7 @@
     <ClInclude Include="utilities\Map.h" />
     <ClInclude Include="utilities\OutputHelper.h" />
     <ClInclude Include="utilities\Timestamp.h" />
+    <ClInclude Include="utilities\Utility.h" />
     <ClInclude Include="utilities\Validator.h" />
     <ClInclude Include="utilities\Vector.h" />
     <ClInclude Include="views\AdminMenu.h" />

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem.vcxproj.filters

@@ -233,5 +233,8 @@
     <ClInclude Include="models\ComboPackage.h">
       <Filter>Header Files\Models</Filter>
     </ClInclude>
+    <ClInclude Include="utilities\Utility.h">
+      <Filter>Header Files\Utilities</Filter>
+    </ClInclude>
   </ItemGroup>
 </Project>

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/models/Invoice.cpp

@@ -16,7 +16,8 @@ Invoice::Invoice(
     const std::string& bookingId,
     ServiceBooking* booking,
     const util::Timestamp& invoiceDate, 
-    double laborCost, const util::Map<int,
+    double laborCost, 
+    const util::Map<std::string,
     InventoryItem*>& parts,
     double partsCost,
     double discountPercentage, 
@@ -63,7 +64,7 @@ double Invoice::getLaborCost() const
     return m_laborCost;
 }
 
-const util::Map<int, InventoryItem*>& Invoice::getParts() const
+const util::Map<std::string, InventoryItem*>& Invoice::getParts() const
 {
     return m_parts;
 }
@@ -123,7 +124,7 @@ void Invoice::setLaborCost(double laborCost)
     m_laborCost = laborCost;
 }
 
-void Invoice::setParts(const util::Map<int, InventoryItem*>& parts)
+void Invoice::setParts(const util::Map<std::string, InventoryItem*>& parts)
 {
     m_parts = parts;
 }

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/models/Invoice.h

@@ -16,7 +16,7 @@ private:
     ServiceBooking* m_booking;
     util::Timestamp m_invoiceDate;
     double m_laborCost;
-    util::Map<int, InventoryItem*> m_parts;
+    util::Map<std::string, InventoryItem*> m_parts;
     double m_partsCost;
     double m_discountPercentage;
     double m_totalAmount;
@@ -30,8 +30,8 @@ public:
         const std::string& bookingId,
         ServiceBooking* booking,
         const util::Timestamp& invoiceDate, 
-        double laborCost, const util::Map<int,
+        double laborCost, 
-        InventoryItem*>& parts,
+        const util::Map<std::string,InventoryItem*>& parts,
         double partsCost,
         double discountPercentage, 
         double totalAmount, 
@@ -44,7 +44,7 @@ public:
     ServiceBooking* getBooking() const;
     const util::Timestamp& getInvoiceDate() const;
     double getLaborCost() const;
-    const util::Map<int, InventoryItem*>& getParts() const;
+    const util::Map<std::string, InventoryItem*>& getParts() const;
     double getPartsCost() const;
     double getDiscountPercentage() const;
     double getTotalAmount() const;
@@ -56,7 +56,7 @@ public:
     void setBooking(ServiceBooking* booking);
     void setInvoiceDate(const util::Timestamp& invoiceDate);
     void setLaborCost(double laborCost);
-    void setParts(const util::Map<int, InventoryItem*>& parts);
+    void setParts(const util::Map<std::string, InventoryItem*>& parts);
     void setPartsCost(double partsCost);
     void setDiscountPercentage(double discountPercentage);
     void setTotalAmount(double totalAmount);

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/models/JobCard.cpp

@@ -7,7 +7,7 @@ JobCard::JobCard()
     m_booking(nullptr),
     m_service(nullptr),
     m_technician(nullptr),
-    m_status(ServiceJobStatus()) {}
+    m_status(util::ServiceJobStatus()) {}
 
 JobCard::JobCard(const std::string& bookingId,
     ServiceBooking* booking,
@@ -16,7 +16,7 @@ JobCard::JobCard(const std::string& bookingId,
     const std::string& technicianId,
     User* technician,
     const util::Timestamp& assignedDate,
-    ServiceJobStatus status,
+    util::ServiceJobStatus status,
     const util::Timestamp& completionDate
 )
     : m_id("JC" + std::to_string(++m_uid)),
@@ -70,7 +70,7 @@ const util::Timestamp& JobCard::getAssignedDate() const
     return m_assignedDate;
 }
 
-ServiceJobStatus JobCard::getStatus() const
+util::ServiceJobStatus JobCard::getStatus() const
 {
     return m_status;
 }
@@ -120,7 +120,7 @@ void JobCard::setAssignedDate(const util::Timestamp& assignedDate)
     m_assignedDate = assignedDate;
 }
 
-void JobCard::setStatus(ServiceJobStatus status)
+void JobCard::setStatus(util::ServiceJobStatus status)
 {
     m_status = status;
 }

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/models/JobCard.h

@@ -1,12 +1,12 @@
 #pragma once
 #include <string>
+#include "Enums.h"
 #include "Timestamp.h"
 
 class ServiceBooking;
 class Service;
 class User;
 
-enum class ServiceJobStatus : int;
 
 class JobCard
 {
@@ -20,7 +20,7 @@ private:
     std::string m_technicianId;
     User* m_technician;
     util::Timestamp m_assignedDate;
-    ServiceJobStatus m_status;
+    util::ServiceJobStatus m_status;
     util::Timestamp m_completionDate;
 
 public:
@@ -32,7 +32,7 @@ public:
         const std::string& technicianId, 
         User* technician, 
         const util::Timestamp& assignedDate, 
-        ServiceJobStatus status,
+        util::ServiceJobStatus status,
         const util::Timestamp& completionDate
     );
     const std::string& getId() const;
@@ -43,7 +43,7 @@ public:
     const std::string& getTechnicianId() const;
     User* getTechnician() const;
     const util::Timestamp& getAssignedDate() const;
-    ServiceJobStatus getStatus() const;
+    util::ServiceJobStatus getStatus() const;
     const util::Timestamp& getCompletionDate() const;
     void setId(const std::string& id);
     void setBookingId(const std::string& bookingId);
@@ -53,6 +53,6 @@ public:
     void setTechnicianId(const std::string& technicianId);
     void setTechnician(User* technician);
     void setAssignedDate(const util::Timestamp& assignedDate);
-    void setStatus(ServiceJobStatus status);
+    void setStatus(util::ServiceJobStatus status);
     void setCompletionDate(const util::Timestamp& completionDate);
 };

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/services/PaymentManagementService.cpp

@@ -1 +1,57 @@
 #include "PaymentManagementService.h"
+#include "ServiceBooking.h"
+#include "Service.h"
+#include "InventoryItem.h"
+#include "Utility.h"
+#include "Factory.h"
+#include "Timestamp.h"
+#include "Invoice.h"
+#include "JobCard.h"
+#include "Enums.h"
+
+static void createInventoryItemsMap(util::Map<std::string, InventoryItem*>& completeInventoryItemMapOfBooking, const Service* currentService)
+{
+	auto& currentRequiredInventoryItems = currentService->getRequiredInventoryItems();
+	for (int iterator = 0; iterator < currentRequiredInventoryItems.getSize(); iterator++)
+	{
+		auto& currentRequiredInventoryItem = currentRequiredInventoryItems.getValueAt(iterator);
+		completeInventoryItemMapOfBooking.insert(currentRequiredInventoryItem->getId(), currentRequiredInventoryItem);
+	}
+}
+
+void PaymentManagementService::generateInvoice(ServiceBooking* booking)
+{
+	if (!booking)
+	{
+		throw std::runtime_error("Invoice generation failed: booking is null.");
+	}
+	double totalLabourCost = 0, totalPartsCost = 0, totalServiceCost = 0;
+	double discountPercentage = booking->getDiscountPercentage();
+	std::string bookingID = booking->getId();
+	util::Map<std::string, Service*> servicesInTheBookedService = booking->getServices();
+	util::Map<std::string, InventoryItem*> completeInventoryItemMapOfBooking;
+	util::Map<std::string, JobCard*> currentJobCards = m_dataStore.getJobCards();
+	for (int iterator = 0; iterator < currentJobCards.getSize(); iterator++)
+	{
+		JobCard* currentJobCard = currentJobCards.getValueAt(iterator);
+		if (currentJobCard->getBookingId() == bookingID && currentJobCard->getStatus() != util::ServiceJobStatus::COMPLETED)
+		{
+			throw std::runtime_error("Invoice generation failed: not all job cards are completed for booking '" + bookingID + "'.");
+		}
+	}
+	for (int iterator = 0; iterator < servicesInTheBookedService.getSize(); iterator++)
+	{
+		Service* currentService = servicesInTheBookedService.getValueAt(iterator);
+		if (currentService)
+		{
+			createInventoryItemsMap(completeInventoryItemMapOfBooking, currentService);
+			totalLabourCost += currentService->getLaborCost();
+			totalPartsCost += calculatePartsCost(currentService);
+		}
+	}
+	totalServiceCost = totalLabourCost + totalPartsCost;
+	totalServiceCost -= (totalServiceCost * (discountPercentage / 100));
+	Invoice* invoice = Factory::getObject<Invoice>(bookingID, booking, util::Timestamp(), totalLabourCost, completeInventoryItemMapOfBooking, totalPartsCost, discountPercentage, totalServiceCost, util::Timestamp(), util::PaymentMode::NOTSET, util::PaymentStatus::PENDING);
+	util::Map<std::string, Invoice*>& currentInvoices = m_dataStore.getInvoices();
+	currentInvoices.insert(invoice->getId(), invoice);
+}

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/utilities/Enums.h

@@ -13,7 +13,8 @@ namespace util
 	enum class PaymentMode
 	{
 		ONLINE,
-		OFFLINE
+		OFFLINE,
+        NOTSET
 	};
 
 	enum class PaymentStatus
@@ -73,6 +74,8 @@ namespace util
             return "ONLINE";
         case PaymentMode::OFFLINE:
             return "OFFLINE";
+        case PaymentMode::NOTSET:
+            return "NOTSET";
         }
         throw std::invalid_argument("Invalid PaymentMode");
     }

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/utilities/Utility.h

@@ -0,0 +1,15 @@
+#pragma once
+#include "Service.h"
+#include "InventoryItem.h"
+
+inline double calculatePartsCost(const Service* service)
+{
+    double cost = 0;
+    auto& requiredInventoryItems = service->getRequiredInventoryItems();
+    int requiredInventoryItemsSize = requiredInventoryItems.getSize();
+    for (int index = 0; index < requiredInventoryItemsSize; index++)
+    {
+        cost += requiredInventoryItems.getValueAt(index)->getPrice();
+    }
+    return cost;
+}