Implement Model Refactoring

<UserStory> 1955: Model Refactoring</UserStory>

UserStory #1955

<Changes>
1. Replaced CSV-based serialization and deserialization in ComboPackage, JobCard, Service, and ServiceBooking models with fixed-size SerializedRecord structures for shared memory storage.
2. Implemented serialize() methods to convert objects into SerializedComboPackage, SerializedJobCard, SerializedService, and SerializedServiceBooking records.
3. Implemented deserialize() methods to reconstruct objects directly from SerializedRecord types instead of parsing CSV strings.
4. Updated model class interfaces to use SerializedRecord types, removing legacy CSV serialization APIs and header generation functions.
5. Added SerializedRecords.h dependencies and forward declarations for Serialized structures across affected models.
</Changes>

<Test>
N/A
</Test>

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

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

@@ -157,7 +157,6 @@
     <ClInclude Include="core\patterns\Observer.h" />
     <ClInclude Include="core\patterns\Subject.h" />
     <ClInclude Include="datastores\DataStore.h" />
-    <ClInclude Include="datastores\DataStoreLockGuard.h" />
     <ClInclude Include="datastores\sharedmemory\FileHeader.h" />
     <ClInclude Include="datastores\sharedmemory\MappingInfo.h" />
     <ClInclude Include="datastores\sharedmemory\RecordState.h" />

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/controllers/Controller.cpp

@@ -588,37 +588,63 @@ void Controller::configureNotifications(bool paymentNotifications, bool serviceN
 }
 
 /*
-Function: initialize
+Function: loadSystemData
-Description: Initializes the system and run system checks to ensure critical configurations, such as verifying admin existence.
+Description: Loads all system data from persistent storage into memory.
-Parameters:
+             Invokes the respective management services to load users, inventory items, services,
-    - None
+             combo packages, service bookings, job cards, invoices, and observers.
-Returns:
-    - bool
-*/
-bool Controller::initialize()
-{
-    auto& dataStore = DataStore::getInstance();
-
-    if (!dataStore.initialize())
-    {
-        return false;
-    }
-    m_userManagementService.ensureAdminExists();
-    m_inventoryManagementService.sendLowStockAlerts();
-    m_paymentManagementService.sendPaymentReminders();
-    return true;
-}
-
-/*
-Function: shutdown
-Description: Shutdown the system, and do necessary cleanups
 Parameters:
     - None
 Returns:
     - void
 */
-void Controller::shutdown()
+void Controller::loadSystemData()
 {
-    auto& dataStore = DataStore::getInstance();
+    m_userManagementService.loadUsers();
-    dataStore.shutdown();
+    m_inventoryManagementService.loadInventoryItems();
+    m_serviceManagementService.loadServices();
+    m_serviceManagementService.loadComboPackages();
+    m_serviceManagementService.loadServiceBookings();
+    m_serviceManagementService.loadJobCards();
+    m_paymentManagementService.loadInvoices();
+    m_serviceManagementService.loadObservers();
+    m_paymentManagementService.loadObservers();
+    m_inventoryManagementService.loadObservers();
 }
+
+/*
+Function: saveSystemData
+Description: Saves all system data from memory back to persistent storage.
+             Invokes the respective management services to save users, inventory items, services,
+             combo packages, service bookings, job cards, invoices, and observers.
+Parameters:
+    - None
+Returns:
+    - void
+*/
+void Controller::saveSystemData()
+{
+    m_userManagementService.saveUsers();
+    m_inventoryManagementService.saveInventoryItems();
+    m_serviceManagementService.saveServices();
+    m_serviceManagementService.saveComboPackages();
+    m_serviceManagementService.saveServiceBookings();
+    m_serviceManagementService.saveJobCards();
+    m_paymentManagementService.saveInvoices();
+    m_serviceManagementService.saveObservers();
+    m_paymentManagementService.saveObservers();
+    m_inventoryManagementService.saveObservers();
+}
+
+/*
+Function: runSystemChecks
+Description: Runs system checks to ensure critical configurations, such as verifying admin existence.
+Parameter: None
+Return type: void
+*/
+void Controller::runSystemChecks()
+{
+    m_userManagementService.ensureAdminExists();
+    m_inventoryManagementService.sendLowStockAlerts();
+    m_paymentManagementService.sendPaymentReminders();
+}
+

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/controllers/Controller.h

@@ -70,6 +70,7 @@ public:
     util::Vector<const Notification*> getNotifications();
     void deleteNotification(const std::string& notificationID);
     void configureNotifications(bool paymentNotifications, bool serviceNotifications);
-    bool initialize();
+    void loadSystemData();
-    void shutdown();
+    void saveSystemData();
+    void runSystemChecks();
 };

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/datastores/DataStore.cpp

@@ -228,22 +228,6 @@ Returns:
 */
 util::Map<std::string, TrackedRecord<User>>& DataStore::getUsers()
 {
-    auto users = loadRecords<User, SerializedUser>(m_users);
-    refreshCache(m_userCache, users);
-    auto& notifications = getNotifications();
-    int numberOfNotifications = m_notificationCache.getSize();
-    for (int index = 0; index < numberOfNotifications; index++)
-    {
-        Notification* notification = notifications.getValueAt(index).data;
-        const std::string& recipientUserId = notification->getRecipientUserId();
-        int userIndex = m_userCache.find(recipientUserId);
-        if (userIndex == -1)
-        {
-            throw std::runtime_error("Invalid recipient user ID");
-        }
-        User* user = m_userCache.getValueAt(userIndex).data;
-        user->addNotification(notification);
-    }
     return m_userCache;
 }
 
@@ -257,8 +241,6 @@ Returns:
 */
 util::Map<std::string, TrackedRecord<Notification>>& DataStore::getNotifications()
 {
-    auto notifications = loadRecords<Notification, SerializedNotification>(m_notifications);
-    refreshCache(m_notificationCache, notifications);
     return m_notificationCache;
 }
 
@@ -389,8 +371,6 @@ Returns:
 */
 void DataStore::saveUsers()
 {
-    saveRecords<User, SerializedUser>(m_users, m_userCache);
-    saveNotifications();
 }
 
 /*
@@ -403,7 +383,6 @@ Returns:
 */
 void DataStore::saveNotifications()
 {
-    saveRecords<Notification, SerializedNotification>(m_notifications, m_notificationCache);
 }
 
 /*

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/datastores/DataStoreLockGuard.h

@@ -1,28 +0,0 @@
-/*
-File: DataStoreLockGuard.h
-Description: Defines the DataStoreLockGuard class used to manage DataStore
-             locking and unlocking automatically within a scope.
-Author: Trenser
-Date: 12-June-2026
-*/
-
-#pragma once
-#include "DataStore.h"
-
-class DataStoreLockGuard
-{
-public:
-    explicit DataStoreLockGuard(DataStore& dataStore)
-        : m_dataStore(dataStore)
-    {
-        m_dataStore.lockDataStore();
-    }
-    ~DataStoreLockGuard()
-    {
-        m_dataStore.unlockDataStore();
-    }
-    DataStoreLockGuard(const DataStoreLockGuard&) = delete;
-    DataStoreLockGuard& operator=(const DataStoreLockGuard&) = delete;
-private:
-    DataStore& m_dataStore;
-};

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/datastores/sharedmemory/SharedMemory.cpp

@@ -10,7 +10,6 @@ Created: 11-June-2026
 */
 
 #include "SharedMemory.h"
-#include "Windows.h"
 #include "Config.h"
 
 /*

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/models/ComboPackage.cpp

@@ -9,6 +9,7 @@ Date: 19-May-2026
 
 #include <sstream>
 #include <stdexcept>
+#include "SerializedRecords.h"
 #include "ComboPackage.h"
 #include "Service.h"
 #include "Factory.h"
@@ -28,7 +29,8 @@ Returns:
 ComboPackage::ComboPackage()
     : m_id("CMP" + std::to_string(++m_uid)),
     m_status(util::State::ACTIVE),
-    m_discountPercentage(0.0) {}
+    m_discountPercentage(0.0) {
+}
 
 /*
 Function: ComboPackage
@@ -270,72 +272,38 @@ static util::Vector<std::string> getServiceIDsAsVector(const std::string& servic
 
 /*
 Function: serialize
-Description: Serializes the combo package into a CSV-formatted string.
+Description: Serializes the ComboPackage object into a SerializedComboPackage record.
 Parameters:
     - None
 Returns:
-    - std::string: Serialized combo package record
+    - SerializedComboPackage: Serialized representation of the combo package
 */
-std::string ComboPackage::serialize() const
+SerializedComboPackage ComboPackage::serialize() const
 {
-    std::ostringstream serializedComboPackage;
+    SerializedComboPackage serialized = {};
-    serializedComboPackage << m_id << ','
+    strcpy_s(serialized.id, sizeof(serialized.id), m_id.c_str());
-        << m_packageName << ','
+    strcpy_s(serialized.packageName, sizeof(serialized.packageName), m_packageName.c_str());
-        << m_discountPercentage << ','
+    strcpy_s(serialized.serviceIDs, sizeof(serialized.serviceIDs), getServiceIDsAsString(m_serviceIDs).c_str());
-        << getServiceIDsAsString(m_serviceIDs) << ','
+    serialized.discountPercentage = m_discountPercentage;
-        << util::getStateString(m_status);
+    serialized.status = m_status;
-    return serializedComboPackage.str();
+    return serialized;
 }
 
 /*
 Function: deserialize
-Description: Deserializes a CSV-formatted string into a ComboPackage object.
+Description: Deserializes a SerializedComboPackage record into a ComboPackage object.
 Parameters:
-    - record: const std::string&, serialized combo package record
+    - serializedComboPackage: const SerializedComboPackage&, serialized combo package record
 Returns:
     - ComboPackage*: Pointer to the deserialized ComboPackage object
-Throws:
-    - std::runtime_error if data is invalid
 */
-ComboPackage* ComboPackage::deserialize(const std::string& record)
+ComboPackage* ComboPackage::deserialize(const SerializedComboPackage& serializedComboPackage)
 {
-    std::string id, packageName;
+    util::Vector<std::string> serviceIDs = getServiceIDsAsVector(serializedComboPackage.serviceIDs);
-    std::string discountPercentageString, serviceIDsString, statusString;
-    double discountPercentage;
-    std::istringstream serializedComboPackage(record);
-    getline(serializedComboPackage, id, ',');
-    getline(serializedComboPackage, packageName, ',');
-    getline(serializedComboPackage, discountPercentageString, ',');
-    getline(serializedComboPackage, serviceIDsString, ',');
-    getline(serializedComboPackage, statusString, ',');
-    try
-    {
-        discountPercentage = std::stod(discountPercentageString);
-    }
-    catch (...)
-    {
-        throw std::runtime_error("Invalid combo package data");
-    }
-    util::Vector<std::string> serviceIDs = getServiceIDsAsVector(serviceIDsString);
-    util::State status = util::getState(statusString);
     return Factory::getObject<ComboPackage>(
-        id,
+        serializedComboPackage.id,
-        packageName,
+        serializedComboPackage.packageName,
-        discountPercentage,
+        serializedComboPackage.discountPercentage,
         serviceIDs,
-        status
+        serializedComboPackage.status);
-    );
+}
-}
-
-/*
-Function: getHeaders
-Description: Retrieves the CSV headers for combo package serialization.
-Parameters:
-    - None
-Returns:
-    - std::string: Header string ("ID,PackageName,DiscountPercentage,ServiceIDs,Status")
-*/
-std::string ComboPackage::getHeaders()
-{
-    return "ID,PackageName,DiscountPercentage,ServiceIDs,Status";
-}

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/models/ComboPackage.h

@@ -12,6 +12,7 @@ Date: 19-May-2026
 #include "Enums.h"
 
 class Service;
+class SerializedComboPackage;
 
 class ComboPackage
 {
@@ -38,7 +39,6 @@ public:
     void setDiscountPercentage(double discountPercentage);
     void setServices(const util::Map<std::string, Service*>& services);
     void setState(util::State status);
-    std::string serialize() const;
+    SerializedComboPackage serialize() const;
-    static ComboPackage* deserialize(const std::string&);
+    static ComboPackage* deserialize(const SerializedComboPackage&);
-    static std::string getHeaders();
 };

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

@@ -9,6 +9,7 @@ Date:19-May-2026
 
 #include <sstream>
 #include <stdexcept>
+#include "SerializedRecords.h"
 #include "JobCard.h"
 #include "Factory.h"
 #include "StringHelper.h"
@@ -28,7 +29,8 @@ JobCard::JobCard()
     m_booking(nullptr),
     m_service(nullptr),
     m_technician(nullptr),
-    m_status(util::ServiceJobStatus()) {}
+    m_status(util::ServiceJobStatus()) {
+}
 
 /*
 Function: JobCard
@@ -65,7 +67,8 @@ JobCard::JobCard(const std::string& bookingId,
     m_technician(technician),
     m_assignedDate(assignedDate),
     m_status(status),
-    m_completionDate(completionDate) {}
+    m_completionDate(completionDate) {
+}
 
 /*
 Function: JobCard (parameterized constructor with ID)
@@ -351,79 +354,41 @@ void JobCard::setCompletionDate(const util::Timestamp& completionDate)
 
 /*
 Function: serialize
-Description: Serializes the job card into a CSV-formatted string.
+Description: Serializes the JobCard object into a SerializedJobCard record.
 Parameters:
     - None
 Returns:
-    - std::string: Serialized job card record
+    - SerializedJobCard: Serialized representation of the job card
 */
-std::string JobCard::serialize() const
+SerializedJobCard JobCard::serialize() const
 {
-    std::ostringstream serializedJobCard;
+    SerializedJobCard serialized = {};
-    serializedJobCard << m_id << ','
+    strcpy_s(serialized.id, sizeof(serialized.id), m_id.c_str());
-        << m_bookingId << ','
+    strcpy_s(serialized.bookingId, sizeof(serialized.bookingId), m_bookingId.c_str());
-        << m_serviceId << ','
+    strcpy_s(serialized.serviceId, sizeof(serialized.serviceId), m_serviceId.c_str());
-        << m_technicianId << ','
+    strcpy_s(serialized.technicianId, sizeof(serialized.technicianId), m_technicianId.c_str());
-        << m_assignedDate.toString() << ','
+    serialized.assignedDate = m_assignedDate;
-        << util::getServiceJobStatusString(m_status) << ','
+    serialized.status = m_status;
-        << m_completionDate.toString();
+    serialized.completionDate = m_completionDate;
-    return serializedJobCard.str();
+    return serialized;
 }
 
 /*
 Function: deserialize
-Description: Deserializes a CSV-formatted string into a JobCard object.
+Description: Deserializes a SerializedJobCard record into a JobCard object.
 Parameters:
-    - record: const std::string&, serialized job card record
+    - serializedJobCard: const SerializedJobCard&, serialized job card record
 Returns:
     - JobCard*: Pointer to the deserialized JobCard object
-Throws:
-    - std::runtime_error if timestamp parsing fails
 */
-JobCard* JobCard::deserialize(const std::string& record)
+JobCard* JobCard::deserialize(const SerializedJobCard& serializedJobCard)
 {
-    std::string id, bookingId, serviceId, technicianId;
-    std::string assignedDateString, statusString, completionDateString;
-    std::istringstream serializedJobCard(record);
-    getline(serializedJobCard, id, ',');
-    getline(serializedJobCard, bookingId, ',');
-    getline(serializedJobCard, serviceId, ',');
-    getline(serializedJobCard, technicianId, ',');
-    getline(serializedJobCard, assignedDateString, ',');
-    getline(serializedJobCard, statusString, ',');
-    getline(serializedJobCard, completionDateString, ',');
-    util::Timestamp assignedDate;
-    util::Timestamp completionDate;
-    try
-    {
-        assignedDate = util::Timestamp::fromString(assignedDateString);
-        completionDate = util::Timestamp::fromString(completionDateString);
-    }
-    catch (...)
-    {
-        throw std::runtime_error("Invalid timestamp");
-    }
-    util::ServiceJobStatus status = util::getServiceJobStatus(statusString);
     return Factory::getObject<JobCard>(
-        id,
+        serializedJobCard.id,
-        bookingId,
+        serializedJobCard.bookingId,
-        serviceId,
+        serializedJobCard.serviceId,
-        technicianId,
+        serializedJobCard.technicianId,
-        assignedDate,
+        serializedJobCard.assignedDate,
-        status,
+        serializedJobCard.status,
-        completionDate
+        serializedJobCard.completionDate);
-    );
-}
-
-/*
-Function: getHeaders
-Description: Retrieves the CSV headers for job card serialization.
-Parameters:
-    - None
-Returns:
-    - std::string: Header string ("ID,BookingID,ServiceID,TechnicianID,AssignedDate,Status,CompletionDate")
-*/
-std::string JobCard::getHeaders()
-{
-    return "ID,BookingID,ServiceID,TechnicianID,AssignedDate,Status,CompletionDate";
 }

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

@@ -15,6 +15,7 @@ Date:19-May-2026
 class ServiceBooking;
 class Service;
 class User;
+struct SerializedJobCard;
 
 class JobCard
 {
@@ -34,11 +35,11 @@ public:
     JobCard();
     JobCard(const std::string& bookingId,
         ServiceBooking* booking,
-        Service* service, 
+        Service* service,
-        const std::string& serviceId, 
+        const std::string& serviceId,
-        const std::string& technicianId, 
+        const std::string& technicianId,
-        User* technician, 
+        User* technician,
-        const util::Timestamp& assignedDate, 
+        const util::Timestamp& assignedDate,
         util::ServiceJobStatus status,
         const util::Timestamp& completionDate
     );
@@ -70,7 +71,6 @@ public:
     void setAssignedDate(const util::Timestamp& assignedDate);
     void setStatus(util::ServiceJobStatus status);
     void setCompletionDate(const util::Timestamp& completionDate);
-    std::string serialize() const;
+    SerializedJobCard serialize() const;
-    static JobCard* deserialize(const std::string&);
+    static JobCard* deserialize(const SerializedJobCard&);
-    static std::string getHeaders();
 };

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/models/Service.cpp

@@ -8,6 +8,7 @@ Date: 19-May-2026
 */
 
 #include <sstream>
+#include "SerializedRecords.h"
 #include "Service.h"
 #include "InventoryItem.h"
 #include "StringHelper.h"
@@ -27,7 +28,8 @@ Returns:
 Service::Service()
     : m_id("SRV" + std::to_string(++m_uid)),
     m_status(util::State::ACTIVE),
-    m_laborCost(0.0) {}
+    m_laborCost(0.0) {
+}
 
 /*
 Function: Service
@@ -44,7 +46,7 @@ Service::Service(const std::string& name, const util::Map<std::string, Inventory
     m_name(name),
     m_requiredInventoryItems(requiredInventoryItems),
     m_status(util::State::ACTIVE),
-    m_laborCost(laborCost) 
+    m_laborCost(laborCost)
 {
     int numberOfInventoryItems = m_requiredInventoryItems.getSize();
     auto inventoryItemPointers = m_requiredInventoryItems.getValues();
@@ -266,72 +268,38 @@ static util::Vector<std::string> getInventoryItemIDsAsVector(const std::string&
 
 /*
 Function: serialize
-Description: Serializes the service into a CSV-formatted string.
+Description: Serializes the Service object into a SerializedService record.
 Parameters:
     - None
 Returns:
-    - std::string: Serialized service record
+    - SerializedService: Serialized representation of the service
 */
-std::string Service::serialize() const
+SerializedService Service::serialize() const
 {
-    std::ostringstream serializedService;
+    SerializedService serialized = {};
-    serializedService << m_id << ','
+    strcpy_s(serialized.id, sizeof(serialized.id), m_id.c_str());
-        << m_name << ','
+    strcpy_s(serialized.name, sizeof(serialized.name), m_name.c_str());
-        << getInventoryItemIDsAsString(m_requiredInventoryItemIDs) << ','
+    strcpy_s(serialized.inventoryItemIDs, sizeof(serialized.inventoryItemIDs), getInventoryItemIDsAsString(m_requiredInventoryItemIDs).c_str());
-        << m_laborCost << ','
+    serialized.laborCost = m_laborCost;
-        << util::getStateString(m_status);
+    serialized.status = m_status;
-    return serializedService.str();
+    return serialized;
 }
 
 /*
 Function: deserialize
-Description: Deserializes a CSV-formatted string into a Service object.
+Description: Deserializes a SerializedService record into a Service object.
 Parameters:
-    - record: const std::string&, serialized service record
+    - serializedService: const SerializedService&, serialized service record
 Returns:
     - Service*: Pointer to the deserialized Service object
-Throws:
-    - std::runtime_error if labor cost parsing fails
 */
-Service* Service::deserialize(const std::string& record)
+Service* Service::deserialize(const SerializedService& serializedService)
 {
-    std::string id, name;
+    util::Vector<std::string> inventoryItemIDs = getInventoryItemIDsAsVector(serializedService.inventoryItemIDs);
-    std::string inventoryItemIDsString, laborCostString, statusString;
-    double laborCost;
-    std::istringstream serializedService(record);
-    getline(serializedService, id, ',');
-    getline(serializedService, name, ',');
-    getline(serializedService, inventoryItemIDsString, ',');
-    getline(serializedService, laborCostString, ',');
-    getline(serializedService, statusString, ',');
-    util::Vector<std::string> inventoryItemIDs = getInventoryItemIDsAsVector(inventoryItemIDsString);
-    try
-    {
-        laborCost = std::stod(laborCostString);
-    }
-    catch (...)
-    {
-        throw std::runtime_error("Invalid labor cost");
-    }
-    util::State status = util::getState(statusString);
     return Factory::getObject<Service>(
-        id,
+        serializedService.id,
-        name,
+        serializedService.name,
         inventoryItemIDs,
-        laborCost,
+        serializedService.laborCost,
-        status
+        serializedService.status);
-    );
-}
-
-/*
-Function: getHeaders
-Description: Retrieves the CSV headers for service serialization.
-Parameters:
-    - None
-Returns:
-    - std::string: Header string ("ID,Name,InventoryIDs,LaborCost,Status")
-*/
-std::string Service::getHeaders()
-{
-    return "ID,Name,InventoryIDs,LaborCost,Status";
 }

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/models/Service.h

@@ -6,7 +6,6 @@ Author: Trenser
 Date: 19-May-2026
 */
 
-
 #pragma once
 #include <string>
 #include "Map.h"
@@ -14,6 +13,7 @@ Date: 19-May-2026
 #include "Enums.h"
 
 class InventoryItem;
+struct SerializedService;
 
 class Service
 {
@@ -40,7 +40,6 @@ public:
     void setRequiredInventoryItems(const util::Map<std::string, InventoryItem*>& requiredInventoryItems);
     void setLaborCost(double laborCost);
     void setState(util::State status);
-    std::string serialize() const;
+    SerializedService serialize() const;
-    static Service* deserialize(const std::string&);
+    static Service* deserialize(const SerializedService&);
-    static std::string getHeaders();
 };

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/models/ServiceBooking.cpp

@@ -6,8 +6,10 @@ Description: Implementation file containing the method definitions of the
 Author: Trenser
 Date:19-May-2026
 */
+
 #include <stdexcept>
 #include <sstream>
+#include "SerializedRecords.h"
 #include "ServiceBooking.h"
 #include "Service.h"
 #include "Enums.h"
@@ -28,7 +30,8 @@ ServiceBooking::ServiceBooking()
     m_customer(nullptr),
     m_assignedTechnician(nullptr),
     m_status(util::ServiceJobStatus::PENDING),
-    m_discountPercentage(0.0) {}
+    m_discountPercentage(0.0) {
+}
 
 /*
 Function: ServiceBooking
@@ -437,84 +440,46 @@ static util::Vector<std::string> getServiceIDsAsVector(const std::string& servic
 
 /*
 Function: serialize
-Description: Serializes the service booking into a CSV-formatted string.
+Description: Serializes the ServiceBooking object into a SerializedServiceBooking record.
 Parameters:
     - None
 Returns:
-    - std::string: Serialized booking record
+    - SerializedServiceBooking: Serialized representation of the service booking
 */
-std::string ServiceBooking::serialize() const
+SerializedServiceBooking ServiceBooking::serialize() const
 {
-    std::ostringstream serializedBooking;
+    SerializedServiceBooking serialized = {};
-    serializedBooking << m_id << ','
+    strcpy_s(serialized.id, sizeof(serialized.id), m_id.c_str());
-        << util::getServiceJobStatusString(m_status) << ','
+    strcpy_s(serialized.serviceIDs, sizeof(serialized.serviceIDs), getServiceIDsAsString(m_serviceIDs).c_str());
-        << getServiceIDsAsString(m_serviceIDs) << ','
+    strcpy_s(serialized.customerId, sizeof(serialized.customerId), m_customerId.c_str());
-        << m_customerId << ','
+    strcpy_s(serialized.vehicleNumber, sizeof(serialized.vehicleNumber), m_vehicleNumber.c_str());
-        << m_vehicleNumber << ','
+    strcpy_s(serialized.vehicleBrand, sizeof(serialized.vehicleBrand), m_vehicleBrand.c_str());
-        << m_vehicleBrand << ','
+    strcpy_s(serialized.vehicleModel, sizeof(serialized.vehicleModel), m_vehicleModel.c_str());
-        << m_vehicleModel << ','
+    strcpy_s(serialized.assignedTechnicianId, sizeof(serialized.assignedTechnicianId), m_assignedTechnicianId.c_str());
-        << m_assignedTechnicianId << ','
+    serialized.status = m_status;
-        << m_discountPercentage << ',';
+    serialized.discountPercentage = m_discountPercentage;
-    return serializedBooking.str();
+    return serialized;
 }
 
 /*
 Function: deserialize
-Description: Deserializes a CSV-formatted string into a ServiceBooking object.
+Description: Deserializes a SerializedServiceBooking record into a ServiceBooking object.
 Parameters:
-    - record: const std::string&, serialized booking record
+    - serializedServiceBooking: const SerializedServiceBooking&, serialized service booking record
 Returns:
     - ServiceBooking*: Pointer to the deserialized ServiceBooking object
-Throws:
-    - std::runtime_error if discount percentage parsing fails
 */
-ServiceBooking* ServiceBooking::deserialize(const std::string& record)
+ServiceBooking* ServiceBooking::deserialize(const SerializedServiceBooking& serializedServiceBooking)
 {
-    std::string id, customerId, vehicleNumber, vehicleBrand, vehicleModel, assignedTechnicianId;
+    util::Vector<std::string> serviceIDs = getServiceIDsAsVector(serializedServiceBooking.serviceIDs);
-    std::string serviceJobStatusString, serviceIDsString, discountPercentageString;
-    double discountPercentage;
-    std::istringstream serializedBooking(record);
-    getline(serializedBooking, id, ',');
-    getline(serializedBooking, serviceJobStatusString, ',');
-    getline(serializedBooking, serviceIDsString, ',');
-    getline(serializedBooking, customerId, ',');
-    getline(serializedBooking, vehicleNumber, ',');
-    getline(serializedBooking, vehicleBrand, ',');
-    getline(serializedBooking, vehicleModel, ',');
-    getline(serializedBooking, assignedTechnicianId, ',');
-    getline(serializedBooking, discountPercentageString, ',');
-    util::Vector<std::string> serviceIDs = getServiceIDsAsVector(serviceIDsString);
-    try
-    {
-        discountPercentage = std::stod(discountPercentageString);
-    }
-    catch (...)
-    {
-        throw std::runtime_error("Invalid discount percentage");
-    }
-    util::ServiceJobStatus status = util::getServiceJobStatus(serviceJobStatusString);
     return Factory::getObject<ServiceBooking>(
-        id,
+        serializedServiceBooking.id,
-        status,
+        serializedServiceBooking.status,
         serviceIDs,
-        customerId,
+        serializedServiceBooking.customerId,
-        vehicleNumber,
+        serializedServiceBooking.vehicleNumber,
-        vehicleBrand,
+        serializedServiceBooking.vehicleBrand,
-        vehicleModel,
+        serializedServiceBooking.vehicleModel,
-        assignedTechnicianId,
+        serializedServiceBooking.assignedTechnicianId,
-        discountPercentage
+        serializedServiceBooking.discountPercentage);
-    );
-}
-
-/*
-Function: getHeaders
-Description: Retrieves the CSV headers for service booking serialization.
-Parameters:
-    - None
-Returns:
-    - std::string: Header string ("ID,Status,ServiceIDs,CustomerID,VehicleNumber,VehicleBrand,VehicleModel,AssignedTechnicianID,DiscountPercentage")
-*/
-std::string ServiceBooking::getHeaders()
-{
-    return "ID,Status,ServiceIDs,CustomerID,VehicleNumber,VehicleBrand,VehicleModel,AssignedTechnicianID,DiscountPercentage";
 }

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/models/ServiceBooking.h

@@ -6,6 +6,7 @@ Description: Header file declaring the ServiceBooking class, which represents
 Author: Trenser
 Date:19-May-2026
 */
+
 #pragma once
 #include <string>
 #include "Map.h"
@@ -14,6 +15,7 @@ Date:19-May-2026
 
 class Service;
 class User;
+struct SerializedServiceBooking;
 
 class ServiceBooking
 {
@@ -78,7 +80,6 @@ public:
     void setAssignedTechnicianId(const std::string& assignedTechnicianId);
     void setAssignedTechnician(User* assignedTechnician);
     void setDiscountPercentage(double discountPercentage);
-    std::string serialize() const;
+    SerializedServiceBooking serialize() const;
-    static ServiceBooking* deserialize(const std::string&);
+    static ServiceBooking* deserialize(const SerializedServiceBooking&);
-    static std::string getHeaders();
 };

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/models/User.cpp

@@ -8,7 +8,6 @@ Date: 19-May-2026
 */
 
 #include <sstream>
-#include "SerializedRecords.h"
 #include "User.h"
 #include "Notification.h"
 #include "Enums.h"
@@ -29,8 +28,7 @@ Returns:
 User::User()
     : m_id("USR" + std::to_string(++m_uid)),
     m_type(util::UserType::CUSTOMER),
-    m_status(util::State::ACTIVE) {
+    m_status(util::State::ACTIVE) {}
-}
 
 /*
 Function: User
@@ -53,8 +51,7 @@ User::User(const std::string& userName, const std::string& password, const std::
     m_phone(phone),
     m_email(email),
     m_type(role),
-    m_status(util::State::ACTIVE) {
+    m_status(util::State::ACTIVE) {}
-}
 
 /*
 Function: User (parameterized constructor with ID)
@@ -327,43 +324,68 @@ void User::setState(util::State status)
 
 /*
 Function: serialize
-Description: Serializes the User object into a SerializedUser record.
+Description: Serializes the user into a CSV-formatted string.
 Parameters:
     - None
 Returns:
-    - SerializedUser: Serialized representation of the user
+    - std::string: Serialized user record
 */
-SerializedUser User::serialize() const
+std::string User::serialize() const
 {
-    SerializedUser serialized = {};
+    std::ostringstream serializedUser;
-    strcpy_s(serialized.id, sizeof(serialized.id), m_id.c_str());
+    serializedUser << m_id << ','
-    strcpy_s(serialized.username, sizeof(serialized.username), m_userName.c_str());
+        << m_userName << ','
-    strcpy_s(serialized.password, sizeof(serialized.password), m_password.c_str());
+        << m_password << ','
-    strcpy_s(serialized.name, sizeof(serialized.name), m_name.c_str());
+        << m_name << ','
-    strcpy_s(serialized.phone, sizeof(serialized.phone), m_phone.c_str());
+        << m_phone << ','
-    strcpy_s(serialized.email, sizeof(serialized.email), m_email.c_str());
+        << m_email << ','
-    serialized.userType = m_type;
+        << util::getUserTypeString(m_type) << ','
-    serialized.status = m_status;
+        << util::getStateString(m_status);
-    return serialized;
+    return serializedUser.str();
 }
 
 /*
 Function: deserialize
-Description: Deserializes a SerializedUser record into a User object.
+Description: Deserializes a CSV-formatted string into a User object.
 Parameters:
-    - serializedUser: const SerializedUser&, serialized user record
+    - record: const std::string&, serialized user record
 Returns:
     - User*: Pointer to the deserialized User object
 */
-User* User::deserialize(const SerializedUser& serializedUser)
+User* User::deserialize(const std::string& record)
 {
-    return Factory::getObject<User>(
+    std::string id, name, username, phone, password, email;
-        serializedUser.id,
+    std::string userTypeString, stateString;
-        serializedUser.username,
+    std::istringstream serializedUser(record);
-        serializedUser.password,
+    getline(serializedUser, id, ',');
-        serializedUser.name,
+    getline(serializedUser, username, ',');
-        serializedUser.phone,
+    getline(serializedUser, password, ',');
-        serializedUser.email,
+    getline(serializedUser, name, ',');
-        serializedUser.userType,
+    getline(serializedUser, phone, ',');
-        serializedUser.status);
+    getline(serializedUser, email, ',');
+    getline(serializedUser, userTypeString, ',');
+    getline(serializedUser, stateString);
+    util::UserType userType = util::getUserType(userTypeString);
+    util::State status = util::getState(stateString);
+    return Factory::getObject<User>(id,
+        username,
+        password,
+        name,
+        phone,
+        email,
+        userType,
+        status);
+}
+
+/*
+Function: getHeaders
+Description: Retrieves the CSV headers for user serialization.
+Parameters:
+    - None
+Returns:
+    - std::string: Header string ("ID,Username,Password,Name,Phone,Email,UserType,UserStatus")
+*/
+std::string User::getHeaders()
+{
+    return "ID,Username,Password,Name,Phone,Email,UserType,UserStatus";
 }

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/models/User.h

@@ -14,7 +14,6 @@ Date: 19-May-2026
 #include "Enums.h"
 
 class Notification;
-struct SerializedUser;
 
 class User : public Observer
 {
@@ -52,6 +51,7 @@ public:
     void addNotification(Notification* notification) override;
     void setRole(util::UserType role);
     void setState(util::State status);
-    SerializedUser serialize() const;
+    std::string serialize() const;
-    static User* deserialize(const SerializedUser& serializedUser);
+    static User* deserialize(const std::string&);
+    static std::string getHeaders();
 };

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/services/UserManagementService.cpp

@@ -20,9 +20,6 @@ Date:19-May-2026
 #include "UserManagementService.h"
 #include "Vector.h"
 #include "Validator.h"
-#include "Utility.h"
-#include "TrackedRecord.h"
-#include "DataStoreLockGuard.h"
 
 /*
 Function: ensureAdminExists
@@ -34,13 +31,12 @@ Return type: void
 */
 void UserManagementService::ensureAdminExists()
 {
-	DataStoreLockGuard lock(m_dataStore);
 	auto& usersMap = m_dataStore.getUsers();
 	int usersMapSize = usersMap.getSize();
 	bool isAdminFound = false;
 	for (int index = 0; index < usersMapSize; index++)
 	{
-		User* user = usersMap.getValueAt(index).data;
+		User* user = usersMap.getValueAt(index);
 		if (user && user->getUserType() == util::UserType::ADMIN)
 		{
 			isAdminFound = true;
@@ -77,9 +73,7 @@ void UserManagementService::createUser(const std::string& username, const std::s
 	InventoryManagementService inventoryManagementService;
 	PaymentManagementService paymentManagementService;
 	ServiceManagementService serviceManagementService;
-	DataStoreLockGuard lock(m_dataStore);
+	auto& usersMap = m_dataStore.getUsers();
-	auto& trackedUsersMap = m_dataStore.getUsers();
-	auto usersMap = util::getObjects(trackedUsersMap);
 	if (util::isUsernameDuplicate(username, usersMap))
 	{
 		throw std::runtime_error("Username already exists");
@@ -93,14 +87,13 @@ void UserManagementService::createUser(const std::string& username, const std::s
 		throw std::runtime_error("Phone already exists");
 	}
 	User* newUser = Factory::getObject<User>(username, password, name, phone, email, type);
-	trackedUsersMap.insert(newUser->getId(), util::createNewRecord(newUser));
+	usersMap.insert(newUser->getId(), newUser);
 	paymentManagementService.attach(newUser);
 	serviceManagementService.attach(newUser);
 	if (newUser->getUserType() == util::UserType::ADMIN)
 	{
 		inventoryManagementService.attach(newUser);
 	}
-	m_dataStore.saveUsers();
 }
 
 /*
@@ -114,24 +107,19 @@ Return type: void
 */
 void UserManagementService::updateUserDetails(const std::string& userID, const std::string& email, const std::string& phone)
 {
-	DataStoreLockGuard lock(m_dataStore);
+	auto& usersMap = m_dataStore.getUsers();
-	auto& trackedUsersMap = m_dataStore.getUsers();
+	int index = usersMap.find(userID);
-	auto usersMap = util::getObjects(trackedUsersMap);
-	int index = trackedUsersMap.find(userID);
 	if (index == -1)
 	{
 		throw std::runtime_error("User does not exist!\n");
 	}
-	User* user = trackedUsersMap.getValueAt(index).data;
+	User* user = usersMap.getValueAt(index);
-	bool isModified = false;
 	if (email != user->getEmail())
 	{
 		if (util::isEmailDuplicate(email, usersMap))
 		{
 			throw std::runtime_error("Email already exists!\n");
 		}
-		user->setEmail(email);
-		isModified = true;
 	}
 	if (phone != user->getPhone())
 	{
@@ -139,14 +127,9 @@ void UserManagementService::updateUserDetails(const std::string& userID, const s
 		{
 			throw std::runtime_error("Phone number already exists!\n");
 		}
-		user->setPhone(phone);
-		isModified = true;
-	}
-	if (isModified)
-	{
-		trackedUsersMap.getValueAt(index).state = RecordState::MODIFIED;
-		m_dataStore.saveUsers();
 	}
+	user->setEmail(email);
+	user->setPhone(phone);
 }
 
 /*
@@ -161,13 +144,12 @@ Throws:
 */
 util::Vector<Notification*> UserManagementService::getUserNotifications(const std::string& userID)
 {
-	DataStoreLockGuard lock(m_dataStore);
+	auto& usersMap = m_dataStore.getUsers();
-	auto& trackedUsersMap = m_dataStore.getUsers(); 
+	if (usersMap.find(userID) == -1)
-	if (trackedUsersMap.find(userID) == -1)
 	{
 		throw std::runtime_error("No user found with given UserID");
 	}
-	User* user = trackedUsersMap[userID].data;
+	User* user = usersMap[userID];
 	if (user)
 	{
 		auto& notifications = user->getNotifications();
@@ -187,41 +169,97 @@ util::Vector<Notification*> UserManagementService::getUserNotifications(const st
 
 /*
 Function: deleteNotification
-Description: Marks a specific notification associated with a given user
+Description: Deletes a specific notification associated with a given user ID.
-			 as inactive.
 Parameters:
 	- notificationID: The unique ID of the notification to be deleted.
 	- userID: The unique ID of the user whose notification is to be deleted.
 Returns:
 	- void
 Throws:
-	- std::runtime_error if no user is found with the given UserID or
+	- std::runtime_error if no user is found with the given UserID or if no notification is found with the given NotificationID.
-	  if no notification is found with the given NotificationID.
 */
 void UserManagementService::deleteNotification(const std::string& notificationID, const std::string& userID)
 {
-	DataStoreLockGuard lock(m_dataStore);
+	auto& usersMap = m_dataStore.getUsers();
-	auto& trackedUsersMap = m_dataStore.getUsers();
+	if (usersMap.find(userID) == -1)
-	auto& trackedNotificationsMap = m_dataStore.getNotifications();
-	int userIndex = trackedUsersMap.find(userID);
-	if (userIndex == -1)
 	{
 		throw std::runtime_error("No user found with given UserID");
 	}
-	User* user = trackedUsersMap.getValueAt(userIndex).data;
+	User* user = usersMap[userID];
 	auto& notifications = user->getNotifications();
 	if (notifications.find(notificationID) == -1)
 	{
 		throw std::runtime_error("No notification found with given NotificationID");
 	}
-	int notificationIndex = trackedNotificationsMap.find(notificationID);
+	notifications.remove(notificationID);
-	if (notificationIndex == -1)
+}
-	{
+
-		throw std::runtime_error("No notification found with given NotificationID");
+/*
-	}
+Function: loadUsers
-	notifications[notificationID]->setState(util::State::INACTIVE);
+Description: Loads users and notifications from persistent storage into the datastore.
-	trackedNotificationsMap.getValueAt(notificationIndex).state = RecordState::MODIFIED;
+             Validates that each notification’s recipient exists and attaches the
-	m_dataStore.saveNotifications();
+             notification to the corresponding user.
+Parameters:
+    - None
+Returns:
+    - void
+Throws:
+    - std::runtime_error if a notification recipient user ID is invalid
+*/
+void UserManagementService::loadUsers()
+{
+    util::FileManager<User> userFileManager(config::file::USER_FILE);
+    util::FileManager<Notification> notificationFileManager(config::file::NOTIFICATION_FILE);
+    auto& users = m_dataStore.getUsers();
+    auto usersMap = userFileManager.load();
+    auto notificationsMap = notificationFileManager.load();
+    int numberOfUsers = usersMap.getSize();
+    int numberOfNotifications = notificationsMap.getSize();
+    for (int index = 0; index < numberOfUsers; index++)
+    {
+        users[usersMap.getKeyAt(index)] = usersMap.getValueAt(index);
+    }
+    for (int index = 0; index < numberOfNotifications; index++)
+    {
+        Notification* notification = notificationsMap.getValueAt(index);
+        const std::string& recipientUserId = notification->getRecipientUserId();
+        int userIndex = users.find(recipientUserId);
+        if (userIndex == -1)
+        {
+            throw std::runtime_error("Invalid recipient user ID");
+        }
+        User* user = users.getValueAt(userIndex);
+        user->addNotification(notification);
+    }
+}
+
+/*
+Function: saveUsers
+Description: Saves users and their notifications from the datastore to persistent storage.
+             Collects notifications from all users into a single map before saving.
+Parameters:
+    - None
+Returns:
+    - void
+*/
+void UserManagementService::saveUsers()
+{
+    util::FileManager<User> userFileManager(config::file::USER_FILE);
+    util::FileManager<Notification> notificationFileManager(config::file::NOTIFICATION_FILE);
+    auto& users = m_dataStore.getUsers();
+    util::Map<std::string, Notification*> notifications;
+    for (int userIndex = 0; userIndex < users.getSize(); userIndex++)
+    {
+        User* user = users.getValueAt(userIndex);
+        auto& userNotifications = user->getNotifications();
+        for (int notificationIndex = 0; notificationIndex < userNotifications.getSize(); notificationIndex++)
+        {
+            notifications[userNotifications.getKeyAt(notificationIndex)] =
+                userNotifications.getValueAt(notificationIndex);
+        }
+    }
+    userFileManager.save(users);
+    notificationFileManager.save(notifications);
 }
 
 /*
@@ -232,9 +270,7 @@ Return type: util::Map<std::string, User*>
 */
 util::Map<std::string, User*> UserManagementService::getUsers()
 {
-	DataStoreLockGuard lock(m_dataStore);
+	return m_dataStore.getUsers();
-	auto users = util::getObjects(m_dataStore.getUsers());
-	return users;
 }
 
 /*
@@ -245,12 +281,10 @@ Return type: User*
 */
 User* UserManagementService::getUser(const std::string& userID)
 {
-	DataStoreLockGuard lock(m_dataStore);
+	int index = m_dataStore.getUsers().find(userID);
-	auto& trackedUsersMap = m_dataStore.getUsers();
-	int index = trackedUsersMap.find(userID);
 	if (index != -1)
 	{
-		return trackedUsersMap.getValueAt(index).data;
+		return m_dataStore.getUsers().getValueAt(index);
 	}
 	return nullptr;
 }
@@ -266,53 +300,35 @@ void UserManagementService::removeUser(const std::string& userID)
 	InventoryManagementService inventoryManagementService;
 	PaymentManagementService paymentManagementService;
 	ServiceManagementService serviceManagementService;
-	DataStoreLockGuard lock(m_dataStore);
+	int index = m_dataStore.getUsers().find(userID);
-	auto& trackedUsersMap = m_dataStore.getUsers();
-	int index = trackedUsersMap.find(userID);
 	if (index != -1)
 	{
-		User* user = trackedUsersMap.getValueAt(index).data;
+		User* user = m_dataStore.getUsers().getValueAt(index);
 		if (user != nullptr)
 		{
 			if (user->getUserType() == util::UserType::CUSTOMER)
 			{
-				serviceManagementService.cancelCustomerServiceBookings(userID);
+				serviceManagementService.cancelCustomerServiceBookings(userID);	
 			}
 			if (user->getUserType() == util::UserType::TECHNICIAN)
 			{
 				serviceManagementService.cancelTechnicianJobs(userID);
 			}
+			user->setState(util::State::INACTIVE);
 			inventoryManagementService.detach(user);
 			paymentManagementService.detach(user);
 			serviceManagementService.detach(user);
-			user->setState(util::State::INACTIVE);
-			trackedUsersMap.getValueAt(index).state = RecordState::MODIFIED;
-			m_dataStore.saveUsers();
 		}
 	}
 }
 
-/*
+util::Map<std::string, User*> UserManagementService::getUsers(util::UserType type)
-Function: getUsers
-Description: Retrieves all active users of the specified type from
-			 the DataStore.
-Parameters:
-	- type: The user type to filter by
-			(ADMIN, CUSTOMER, or TECHNICIAN).
-Returns:
-	- util::Map<std::string, User*>:
-	  Collection of active users matching the specified type,
-	  keyed by user ID.
-*/
-util::Map<std::string, User*> UserManagementService::getUsers(util::UserType type) 
 {
-	DataStoreLockGuard lock(m_dataStore);
+	util::Map<std::string, User*>& currentUsers = m_dataStore.getUsers();
-	auto& trackedUsersMap = m_dataStore.getUsers();
-	util::Map<std::string, User*> currentUsers = util::getObjects(trackedUsersMap);
 	util::Map<std::string, User*> filteredUsersMap;
-	for (int index = 0; index < currentUsers.getSize(); index++)
+	for (int iterator = 0; iterator < currentUsers.getSize(); iterator++)
 	{
-		User* currentUser = currentUsers.getValueAt(index);
+		User* currentUser = currentUsers.getValueAt(iterator);
 		if (currentUser && currentUser->getState() == util::State::ACTIVE && currentUser->getUserType() == type)
 		{
 			filteredUsersMap.insert(currentUser->getId(), currentUser);

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/services/UserManagementService.h

@@ -31,4 +31,6 @@ public:
     util::Vector<Notification*> getUserNotifications(const std::string& userID);
     void deleteNotification(const std::string& notificationID, const std::string& userID);
     void ensureAdminExists();
+    void loadUsers();
+    void saveUsers();
 };

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/views/UserInterface.cpp

@@ -27,11 +27,8 @@ void UserInterface::run()
 {
 	try
 	{
-		if (!m_controller.initialize())
+		m_controller.loadSystemData();
-		{
+		m_controller.runSystemChecks();
-			std::cout << "Error: Failed to initialize the system!";
-			return;
-		}
 		bool isMenuActive = true;
 		while (isMenuActive)
 		{
@@ -52,7 +49,7 @@ void UserInterface::run()
 				util::pressEnter();
 			}
 		}
-		m_controller.shutdown();
+		m_controller.saveSystemData();
 	}
 	catch (const std::invalid_argument& exception)
 	{