Implement serialization/deserialization and persistent storage across services

- Add serialize/deserialize support for core models
- Add file-based load/save functions in management services
- Introduce FileManager, Config, Utility and helper utilities
- Persist observer IDs for notification services
- Resolve object relationships during load (services, bookings, invoices, job cards)
- Add controller-level loadSystemData/saveSystemData
- Load data at app startup and save on shutdown

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

@@ -1,4 +1,9 @@
+#include <sstream>
+#include <stdexcept>
 #include "JobCard.h"
+#include "Factory.h"
+#include "StringHelper.h"
+#include "Enums.h"
 
 int JobCard::m_uid = 0;
 
@@ -7,7 +12,7 @@ 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 +21,7 @@ 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)),
@@ -30,6 +35,32 @@ JobCard::JobCard(const std::string& bookingId,
     m_status(status),
     m_completionDate(completionDate) {}
 
+JobCard::JobCard(const std::string& id,
+    const std::string& bookingId,
+    const std::string& serviceId,
+    const std::string& technicianId,
+    const util::Timestamp& assignedDate,
+    util::ServiceJobStatus status,
+    const util::Timestamp& completionDate
+)
+    : m_id(id),
+    m_bookingId(bookingId),
+    m_booking(nullptr),
+    m_service(nullptr),
+    m_serviceId(serviceId),
+    m_technicianId(technicianId),
+    m_technician(nullptr),
+    m_assignedDate(assignedDate),
+    m_status(status),
+    m_completionDate(completionDate)
+{
+    int idNumber = util::extractNumber(m_id);
+    if (idNumber > m_uid)
+    {
+        m_uid = idNumber;
+    }
+}
+
 const std::string& JobCard::getId() const
 {
     return m_id;
@@ -70,7 +101,7 @@ const util::Timestamp& JobCard::getAssignedDate() const
     return m_assignedDate;
 }
 
-ServiceJobStatus JobCard::getStatus() const
+util::ServiceJobStatus JobCard::getStatus() const
 {
     return m_status;
 }
@@ -120,7 +151,7 @@ void JobCard::setAssignedDate(const util::Timestamp& assignedDate)
     m_assignedDate = assignedDate;
 }
 
-void JobCard::setStatus(ServiceJobStatus status)
+void JobCard::setStatus(util::ServiceJobStatus status)
 {
     m_status = status;
 }
@@ -128,4 +159,57 @@ void JobCard::setStatus(ServiceJobStatus status)
 void JobCard::setCompletionDate(const util::Timestamp& completionDate)
 {
     m_completionDate = completionDate;
+}
+
+std::string JobCard::serialize() const
+{
+    std::ostringstream serializedJobCard;
+    serializedJobCard << m_id << ','
+        << m_bookingId << ','
+        << m_serviceId << ','
+        << m_technicianId << ','
+        << m_assignedDate.toString() << ','
+        << util::getServiceJobStatusString(m_status) << ','
+        << m_completionDate.toString();
+    return serializedJobCard.str();
+}
+
+JobCard* JobCard::deserialize(const std::string& record)
+{
+    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,
+        bookingId,
+        serviceId,
+        technicianId,
+        assignedDate,
+        status,
+        completionDate
+    );
+}
+
+std::string JobCard::getHeaders()
+{
+    return "ID,BookingID,ServiceID,TechnicianID,AssignedDate,Status,CompletionDate";
 }