COVIDSafe code from version 1.1

CovidSafe/ContactViewController.swift

@@ -0,0 +1,84 @@
+import UIKit
+import CoreData
+
+final class ContactViewController: UIViewController {
+    @IBOutlet var contactTableView: UITableView!;
+    var sortedContacts:[(contactId: String, count: Int)] = []
+    var fetchedResultsController: NSFetchedResultsController<Encounter>?;
+    
+    override func viewWillAppear(_ animated: Bool) {
+        super.viewWillAppear(animated)
+        fetchContacts()
+    }
+    
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        contactTableView.dataSource = self
+        contactTableView.register(UITableViewCell.self,
+                                  forCellReuseIdentifier: "ContactCell")
+    }
+    
+    func fetchContacts() {
+        guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else {
+            return
+        }
+        let managedContext = appDelegate.persistentContainer.viewContext
+        let fetchRequest = Encounter.fetchRequestForRecords()
+        let sortByContactId = NSSortDescriptor(key: "msg", ascending: false)
+        fetchRequest.sortDescriptors = [sortByContactId]
+        fetchedResultsController = NSFetchedResultsController<Encounter>(fetchRequest: fetchRequest, managedObjectContext: managedContext, sectionNameKeyPath: nil, cacheName: nil)
+        fetchedResultsController?.delegate = self
+        
+        do {
+            try fetchedResultsController?.performFetch()
+            updateSortedContacts()
+        } catch let error as NSError {
+            print("Could not perform fetch. \(error), \(error.userInfo)")
+        }
+        
+    }
+    
+    func updateSortedContacts() {
+        guard let encounters = fetchedResultsController?.fetchedObjects else {
+            return
+        }
+        var contactCounts: [String: Int] = [:]
+        for encounter in encounters {
+            if encounter.msg != nil {
+                if contactCounts[encounter.msg!] == nil {
+                    contactCounts[encounter.msg!] = 0
+                }
+                contactCounts[encounter.msg!]! += 1
+            }
+        }
+        var contactTuples = contactCounts.map { ($0.key, $0.value) }
+        contactTuples.sort {
+            $0.1 > $1.1
+        }
+        sortedContacts = contactTuples
+    }
+}
+
+extension ContactViewController: UITableViewDataSource {
+    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
+        return self.sortedContacts.count
+    }
+    
+    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
+        let cell = tableView.dequeueReusableCell(withIdentifier: "ContactCell", for: indexPath)
+        let contact = self.sortedContacts[indexPath.row]
+        cell.textLabel?.text = "\(contact.contactId) [\(contact.count) encounters]"
+        cell.textLabel?.numberOfLines = 0
+        return cell
+    }
+}
+
+
+extension ContactViewController  : NSFetchedResultsControllerDelegate{
+    func controller(_ controller: NSFetchedResultsController<NSFetchRequestResult>, didChange anObject: Any, at indexPath: IndexPath?, for type: NSFetchedResultsChangeType, newIndexPath: IndexPath?) {
+        
+        updateSortedContacts()
+        
+        contactTableView.reloadData()
+    }
+}