Add documentation headers across system modules

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

@@ -5,6 +5,15 @@
 #include "Utility.h"
 #include "Config.h"
 
+/*
+Function: getObserverIDs
+Description: Retrieves the IDs of all observers currently attached to the
+             PaymentManagementService.
+Parameters:
+    - None
+Returns:
+    - util::Vector<std::string>: Vector of observer user IDs
+*/
 util::Vector<std::string> PaymentManagementService::getObserverIDs()
 {
 	util::Vector<std::string> observerIDs;
@@ -20,6 +29,19 @@ util::Vector<std::string> PaymentManagementService::getObserverIDs()
 	return observerIDs;
 }
 
+/*
+Function: loadInvoices
+Description: Loads invoices from persistent storage into the datastore.
+             Validates associated service bookings and inventory parts before
+             attaching them to each invoice. Throws exceptions if invalid IDs
+             are encountered.
+Parameters:
+    - None
+Returns:
+    - void
+Throws:
+    - std::runtime_error if a booking ID or part ID is invalid
+*/
 void PaymentManagementService::loadInvoices()
 {
     util::FileManager<Invoice> invoiceFileManager(config::file::INVOICE_FILE);
@@ -53,6 +75,16 @@ void PaymentManagementService::loadInvoices()
         invoices[invoice->getId()] = invoice;
     }
 }
+
+/*
+Function: saveInvoices
+Description: Saves invoices from the datastore to persistent storage.
+             Uses FileManager to serialize invoices into the configured file.
+Parameters:
+    - None
+Returns:
+    - void
+*/
 void PaymentManagementService::saveInvoices()
 {
     util::FileManager<Invoice> invoiceFileManager(config::file::INVOICE_FILE);
@@ -60,12 +92,32 @@ void PaymentManagementService::saveInvoices()
     invoiceFileManager.save(invoices);
 }
 
+/*
+Function: loadObservers
+Description: Loads observer IDs from persistent storage and attaches corresponding
+             users as observers to the PaymentManagementService.
+Parameters:
+    - None
+Returns:
+    - void
+Throws:
+    - std::runtime_error if an observer ID is invalid (not found in datastore)
+*/
 void PaymentManagementService::loadObservers()
 {
     util::loadObservers(config::file::PAYMENTMANAGEMENTOBSERVERS, this, m_dataStore);
 }
 
+/*
+Function: saveObservers
+Description: Saves the current observer IDs of the PaymentManagementService
+             to persistent storage for future retrieval.
+Parameters:
+    - None
+Returns:
+    - void
+*/
 void PaymentManagementService::saveObservers()
 {
     util::saveObservers(config::file::PAYMENTMANAGEMENTOBSERVERS, this);
-}
+}