added paging

Signed-off-by: Matt Bruce <mbrucedogs@gmail.com>

EmployeeDirectory/ViewControllers/EmployeesViewController.swift

@@ -31,6 +31,9 @@ class EmployeesViewController: UIViewController {
     /// Will show specific state of the viewModel
     private var footerView: TableFooterView?
     
+    // Prevents multiple calls during rapid scrolling
+    private var isFetchingNextPage: Bool = false
+
     // MARK: - Public Methods
 
     public override func viewDidLoad() {
@@ -49,6 +52,7 @@ class EmployeesViewController: UIViewController {
         // Configure TableView
         tableView.register(EmployeeTableViewCell.self, forCellReuseIdentifier: EmployeeTableViewCell.identifier)
         tableView.dataSource = self
+        tableView.delegate = self
         view.addSubview(tableView)
         tableView.frame = view.bounds
 
@@ -98,26 +102,55 @@ class EmployeesViewController: UIViewController {
     
     /// Show state in specific use-cases for the EmployeesViewModel
     private func updateFooter() {
-        var message: String? {
-            guard !viewModel.isLoading else { return nil }
-            return viewModel.errorMessage ?? (viewModel.employees.isEmpty ? "No employees found, please try to refresh." : nil)
+        var footerMessage: String?
+        
+        // Check for error messages or empty state first
+        if let message = viewModel.errorMessage ?? (viewModel.employees.isEmpty && !viewModel.isLoading ? "No employees found, please try to refresh." : nil) {
+            footerMessage = message
+            
+        }        
+        // Show loading footer if there are more pages to load
+        else if (viewModel.isLoading || isFetchingNextPage) && viewModel.hasMorePages {
+            footerMessage = "Loading more employees..."
         }
         
-        if let message, !viewModel.isLoading {
+        if let footerMessage {
             // Lazy initialize footerView if needed
             if footerView == nil {
-                footerView = TableFooterView(message: message)
-            } else { // Update the message
-                footerView?.update(message: message)
+                footerView = TableFooterView(message: footerMessage)
+            } else {
+                footerView?.update(message: footerMessage)
             }
             footerView?.frame = CGRect(x: 0, y: 0, width: tableView.frame.width, height: 150)
             tableView.tableFooterView = footerView
+
         } else {
             tableView.tableFooterView = nil
         }
     }
 }
 
+// MARK: - UITableViewDelegate
+extension EmployeesViewController: UITableViewDelegate {
+    func scrollViewDidScroll(_ scrollView: UIScrollView) {
+        let offsetY = scrollView.contentOffset.y
+        let contentHeight = scrollView.contentSize.height
+        let scrollViewHeight = scrollView.frame.size.height
+
+        if offsetY > contentHeight - scrollViewHeight - 100 && !isFetchingNextPage {
+            isFetchingNextPage = true
+            updateFooter()
+            viewModel.loadNextPage()
+
+            // Reset the flag after a short delay to allow new fetches
+            DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) { [weak self] in
+                self?.isFetchingNextPage = false
+            }
+        }
+    }
+}
+
+
 // Mark: - Objective-C Methods
 extension EmployeesViewController {
     

EmployeeDirectory/ViewModels/EmployeesViewModel.swift

@@ -16,36 +16,57 @@ public class EmployeesViewModel: ObservableObject {
     @Published public private(set) var employees: [Employee] = []
     @Published public private(set) var errorMessage: String? = nil
     @Published public private(set) var isLoading: Bool = false
-    
+    @Published public private(set) var hasMorePages: Bool = true
+
+    private var currentPage = 1
+    private let perPage = 10
+    private var totalEmployees = 0
+
     public init() {}
-    
-    public func fetchEmployees() {
-        // resetting values out the values before fetching new data
-        errorMessage = nil
+
+    /// Fetch employees for the given page
+    public func fetchEmployees(page: Int = 1) {
+        // Prevent duplicate calls
+        guard !isLoading else { return }
         isLoading = true
 
         Task {
             do {
-                // Fetch employees using the async method
-                let wrapper = try await EmployeeService.shared.getEmployees(serviceMode)
+                // Fetch employees using the paginated API
+                let wrapper = try await MockEmployeeService.shared.getEmployees(.empty ,page: page, perPage: perPage)
                 
                 // Update published properties
-                employees = wrapper.employees
+                if page == 1 {
+                    employees = wrapper.employees // Replace list for the first page
+                } else {
+                    employees.append(contentsOf: wrapper.employees) // Append for subsequent pages
+                }
+                
+                totalEmployees = wrapper.total
+                currentPage = page
+                hasMorePages = employees.count < totalEmployees
                 isLoading = false
 
             } catch {
                 // Handle errors
-                employees = []
                 isLoading = false
-                errorMessage = "An unexpected error occurred, please try to refresh"
+                errorMessage = "An unexpected error occurred, please try to refresh."
             }
         }
-
     }
-    
+
+    /// Load the next page of employees
+    public func loadNextPage() {
+        guard hasMorePages else { return }
+        fetchEmployees(page: currentPage + 1)
+    }
+
+    /// Change the service mode (e.g., production, malformed, empty)
     public func changeMode(to mode: EmployeeServiceMode) {
         serviceMode = mode
-        fetchEmployees()
+        currentPage = 1
+        employees = []
+        hasMorePages = true
+        fetchEmployees(page: 1)
     }
 }
-