SyncbaseTodosApp/SyncbaseTodos/InviteViewController.swift - release.swift - Git at Google

 // Copyright 2016 The Vanadium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.

 import Contacts
 import ContactsUI
 import Syncbase
 import UIKit

 enum Category: Int {
   case NearbyContacts
   case Nearby
   case Contacts
   static let allRawValues = [NearbyContacts.rawValue, Nearby.rawValue, Contacts.rawValue]
 }

 class InviteViewController: UITableViewController {
   // Represents the search bar.
   var searchController: UISearchController!
   // All known people -- this is the model that the tableview loads from.
   var people: [[Contact]] = [[], [], []]
   // Allows us to look up address book contacts we might discover via BLE/mDNS.
   var contactsByLowercaseEmail: [String: Contact] = [:]
   var contactsByLowercaseEmailMu = NSLock()
   // True if the search controller's text matches any existing contacts.
   var searchResultsFound = false
   // All matching people for a given search -- this is the model the tableview loads from.
   var searchResults: [[Contact]] = [[], [], []]
   // True if contacts were able to be loaded from the iOS Address Book.
   var didLoadContacts = false
   // The TodoList we are inviting users to.
   var todoList: TodoList!

   // Regex used to know when a search represents an email address.
   let emailRegEx = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,}"
   // The cell that displays people's names or emails.
   let personCellId = "personCellId"
   // The cell that represents sending an invite directly to an email address.
   let sendEmailCell = "sendEmailCellId"
   // The names of each section of the table view.
   var sectionNames: [Category: String] = [
       .NearbyContacts: "Nearby Contacts",
       .Nearby: "Nearby",
       .Contacts: "Contacts",
   ]
   // Set to true if the user clicked on a name to invite while the seearch controller was active.
   // The invite logic first waits for the search controller to turn inactive before the view
   // controller is dismissed. This variable keeps track for the didDismissSearchController callback
   // to know if it should dismiss the VC or not.
   var shouldDismiss = false

   override func viewDidLoad() {
     super.viewDidLoad()
     guard todoList.collection != nil else {
       print("Missing collection from todo list \(todoList)")
       // Pop view since we can't invite a user. This must be done outside of the viewDidLoad.
       dispatch_async(dispatch_get_main_queue()) {
         self.dismissViewControllerAnimated(true) { }
       }
       return
     }
     initSearchController()
     loadContacts() {
       do {
         try Syncbase.startScanForUsersInNeighborhood(
           ScanNeighborhoodForUsersHandler(onFound: self.onFound, onLost: self.onLost))
       } catch {
         print("Unable to scan for other users: \(error)")
       }
     }
   }

   override func viewWillDisappear(animated: Bool) {
     Syncbase.stopAllScansForUsersInNeighborhood()
   }

   func initSearchController() {
     // Cannot be done in IB yet.
     searchController = UISearchController(searchResultsController: nil)
     searchController.delegate = self
     searchController.searchResultsUpdater = self
     searchController.dimsBackgroundDuringPresentation = false
     searchController.searchBar.sizeToFit()
     tableView.tableHeaderView = searchController.searchBar
     definesPresentationContext = true
   }

   // MARK: Address Book contacts

   func loadContacts(doneCallback: Void -> Void) {
     CNContactStore().requestAccessForEntityType(.Contacts) { (granted, error) in
       guard granted && error == nil else {
         print("Contants not able to load: granted=\(granted) error=\(error)")
         dispatch_async(dispatch_get_main_queue()) {
           self.disableContacts()
           doneCallback()
         }
         return
       }
       let request = CNContactFetchRequest(keysToFetch: Contact.keysToFetch)
       var results: [Contact] = []
       do {
         self.contactsByLowercaseEmailMu.lock()
         defer { self.contactsByLowercaseEmailMu.unlock() }
         // This is a bit slow loading everything at once. In a real app you want to take a more
         // advanced strategy, perhaps updating the UI in batches or some other methodology.
         try CNContactStore().enumerateContactsWithFetchRequest(request) { (cncontact, stop) in
           let contact = Contact(contact: cncontact)
           results.append(contact)
           if let emails = contact.emails {
             for email in emails {
               // The email was lowercased in the Contact class's init.
               self.contactsByLowercaseEmail[email] = contact
             }
           }
         }
         dispatch_async(dispatch_get_main_queue()) {
           self.didLoadContacts = true
           self.people[Category.Contacts.rawValue] = results
           self.tableView.reloadData()
           doneCallback()
         }
       } catch {
         print("Unable to fetch contacts: \(error)")
         dispatch_async(dispatch_get_main_queue()) {
           self.disableContacts()
           doneCallback()
         }
       }
     }
   }

   /// disableContacts is used when the user has not granted authorization to contacts or some other
   /// error has occured loading contacts. Must be called from main.
   func disableContacts() {
     didLoadContacts = false
     sectionNames[.Contacts] = nil
     sectionNames[.NearbyContacts] = nil
     people = [people[Category.Nearby.rawValue]]
     searchResults = [searchResults[Category.Nearby.rawValue]]
     tableView.reloadData()
   }

   // MARK: Tableview delegates

   override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
     if searchController.active && !searchResultsFound {
       // We only have one section in the case of the send email cell.
       return 1
     }
     return sectionNames.count
   }

   override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
     if searchController.active {
       if searchResultsFound {
         return searchResults[section].count
       } else {
         // We only have one row in the case of the send email cell.
         return 1
       }
     }
     return people[section].count
   }

   override func tableView(tableView: UITableView, willDisplayHeaderView view: UIView, forSection section: Int) {
     view.tintColor = UIColor.whiteColor()
   }

   override func tableView(tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
     if searchController.active && !searchResultsFound {
       // Don't show a section title if we're just showing send an email cell.
       return nil
     }
     return sectionNames[Category(rawValue: section)!]
   }

   override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
     // In the case where we have are searching and have found no results, offer the send email cell.
     if searchController.active && !searchResultsFound {
       // This cell is a prototype inside the Main.storyboard. Cannot fail.
       let cell = tableView.dequeueReusableCellWithIdentifier(sendEmailCell, forIndexPath: indexPath) as! SendEmailCell
       cell.emailLabel.text = searchController.searchBar.text
       return cell
     }

     // This cell is a prototype inside the Main.storyboard. Cannot fail.
     let cell = self.tableView.dequeueReusableCellWithIdentifier(personCellId, forIndexPath: indexPath) as! PersonCell
     if searchController.active {
       // Show search results.
       cell.contact = searchResults[indexPath.section][indexPath.row]
     } else {
       // Not searching, show entire list.
       cell.contact = people[indexPath.section][indexPath.row]
     }
     cell.updateView()
     return cell
   }

   override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
     if searchController.active && !searchResultsFound {
       return SendEmailCell.height
     }
     return PersonCell.height
   }

   // MARK: Inviting

   override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
     // No-op if can't create a person from index path.
     if let contact = contactAtIndexPath(indexPath) {
       do {
         try inviteContact(contact)
       } catch {
         print("Unable to invite \(contact): \(error)")
         let ac = UIAlertController(
           title: "Oops!",
           message: "Unable to send invite. Try again.",
           preferredStyle: .Alert)
         ac.addAction(UIAlertAction(title: "OK", style: .Default, handler: nil))
         presentViewController(ac, animated: true, completion: nil)
         return
       }
       // Dismiss the view.
       if searchController.active {
         // The search bar needs to close before we pop, so handle in didDismissSearch callback.
         shouldDismiss = true
         searchController.active = false
       } else {
         navigationController?.popViewControllerAnimated(true)
       }
     }
   }

   func contactAtIndexPath(indexPath: NSIndexPath) -> Contact? {
     // Determine if we entered an email or not. If email, validate email and construct a Person obj.
     var personToInvite: Contact?
     if let text = searchController.searchBar.text where searchController.active && !searchResultsFound {
       let validEmail = NSPredicate(format: "SELF MATCHES %@", emailRegEx).evaluateWithObject(text)
       if validEmail {
         // Create new person with this email.
         personToInvite = Contact(emails: [text])
       } else {
         // Invalid email, show alert.
         let alert = UIAlertController(title: "Invalid email",
           message: "Please enter a valid email",
           preferredStyle: .Alert)
         alert.addAction(UIAlertAction(title: "Ok", style: .Default, handler: nil))
         navigationController?.presentViewController(alert, animated: true, completion: nil)
       }
     } else if people.indices.contains(indexPath.section) &&
     people[indexPath.section].indices.contains(indexPath.row) {
       // We're inviting an existing Person.
       personToInvite = people[indexPath.section][indexPath.row]
     }
     return personToInvite
   }

   // This is called after selecting a contact if the search controller is active.
   func didDismissSearchController(searchController: UISearchController) {
     // If we were searching when we selected a person, we need to wait for its dismiss animation
     // to finish before popping the view.
     if shouldDismiss {
       navigationController?.popViewControllerAnimated(true)
     }
   }

   // inviteContact is the function responsible for actually inviting a user to the collection's
   // syncgroup.
   func inviteContact(contact: Contact) throws {
     if let user = contact.user {
       // Admin allows them to invite people to the syncgroup as well.
       try todoList.collection!.syncgroup().inviteUser(user, level: .READ_WRITE_ADMIN)
     } else if let emails = contact.emails {
       for email in emails {
         try todoList.collection!.syncgroup().inviteUser(User(alias: email), level: .READ_WRITE_ADMIN)
       }
     }
   }

   // MARK: Discovery

   func onFound(user: User) {
     dispatch_async(dispatch_get_global_queue(QOS_CLASS_BACKGROUND, 0)) {
       // Determine if they're an existing contact.
       self.contactsByLowercaseEmailMu.lock()
       defer { self.contactsByLowercaseEmailMu.unlock() }
       var contact = Contact(user: user)
       var section = Category.Nearby.rawValue
       if let existingContact = self.contactsByLowercaseEmail[user.alias.lowercaseString] {
         contact = existingContact
         contact.user = user
         section = Category.NearbyContacts.rawValue
       }
       // If we were never able to load contacts, then they should be disabled and we only have 1
       // section.
       if !self.didLoadContacts {
         section = 0
       }
       dispatch_async(dispatch_get_main_queue()) {
         self.people[section].append(contact)
         self.people[section].sortInPlace { (lhs, rhs) -> Bool in
           return lhs.description.compare(rhs.description) == NSComparisonResult.OrderedAscending
         }
         self.tableView.reloadSections(NSIndexSet(index: section), withRowAnimation: .Automatic)
       }
     }
   }

   func onLost(user: User) {
     for section in nearbySections {
       if let idx = people[section].indexOf({ $0.user == user }) {
         people[section].removeAtIndex(idx)
         tableView.reloadSections(NSIndexSet(index: section), withRowAnimation: .Automatic)
         break
       }
     }
   }

   var nearbySections: [Int] {
     if didLoadContacts {
       return [Category.NearbyContacts.rawValue, Category.Nearby.rawValue]
     }
     return [0]
   }
 }

 // MARK: Search

 // Filters people to match the text user searched for.
 extension InviteViewController: UISearchControllerDelegate, UISearchResultsUpdating {
   func updateSearchResultsForSearchController(searchController: UISearchController) {
     if let searchText = searchController.searchBar.text where searchText.characters.count > 0 {
       for section in nearbySections {
         searchResults[section] = people[section].filter { contact -> Bool in
           return contact.description.rangeOfString(searchText,
             options: .CaseInsensitiveSearch,
             range: contact.description.startIndex ..< contact.description.endIndex,
             locale: nil) != nil
         }
       }
       if didLoadContacts {
         searchResults[Category.Contacts.rawValue] = []
         if let contacts = try? CNContactStore().unifiedContactsMatchingPredicate(
           CNContact.predicateForContactsMatchingName(searchText),
           keysToFetch: Contact.keysToFetch) {
             searchResults[Category.Contacts.rawValue] = contacts.map { Contact(contact: $0) }
         }
       }
     } else {
       for i in 0 ..< searchResults.count {
         searchResults[i] = []
       }
     }
     searchResultsFound = false
     for section in searchResults {
       if !section.isEmpty {
         searchResultsFound = true
         break
       }
     }
     tableView.reloadData()
   }
 }

 // MARK: Tableview Cells

 // Displays a person with name and their profile photo.
 class PersonCell: UITableViewCell {
   static let height: CGFloat = 44
   @IBOutlet weak var nameLabel: UILabel!
   var contact: Contact?

   func updateView() {
     nameLabel.text = contact?.description
   }
 }

 // Display a cell that shows the email the invite will be sent to.
 class SendEmailCell: UITableViewCell {
   static let height: CGFloat = 74
   @IBOutlet weak var emailLabel: UILabel!
 }
	// Copyright 2016 The Vanadium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style
	// license that can be found in the LICENSE file.

	import Contacts
	import ContactsUI
	import Syncbase
	import UIKit

	enum Category: Int {
	case NearbyContacts
	case Nearby
	case Contacts
	static let allRawValues = [NearbyContacts.rawValue, Nearby.rawValue, Contacts.rawValue]
	}

	class InviteViewController: UITableViewController {
	// Represents the search bar.
	var searchController: UISearchController!
	// All known people -- this is the model that the tableview loads from.
	var people: [[Contact]] = [[], [], []]
	// Allows us to look up address book contacts we might discover via BLE/mDNS.
	var contactsByLowercaseEmail: [String: Contact] = [:]
	var contactsByLowercaseEmailMu = NSLock()
	// True if the search controller's text matches any existing contacts.
	var searchResultsFound = false
	// All matching people for a given search -- this is the model the tableview loads from.
	var searchResults: [[Contact]] = [[], [], []]
	// True if contacts were able to be loaded from the iOS Address Book.
	var didLoadContacts = false
	// The TodoList we are inviting users to.
	var todoList: TodoList!

	// Regex used to know when a search represents an email address.
	let emailRegEx = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,}"
	// The cell that displays people's names or emails.
	let personCellId = "personCellId"
	// The cell that represents sending an invite directly to an email address.
	let sendEmailCell = "sendEmailCellId"
	// The names of each section of the table view.
	var sectionNames: [Category: String] = [
	.NearbyContacts: "Nearby Contacts",
	.Nearby: "Nearby",
	.Contacts: "Contacts",
	]
	// Set to true if the user clicked on a name to invite while the seearch controller was active.
	// The invite logic first waits for the search controller to turn inactive before the view
	// controller is dismissed. This variable keeps track for the didDismissSearchController callback
	// to know if it should dismiss the VC or not.
	var shouldDismiss = false

	override func viewDidLoad() {
	super.viewDidLoad()
	guard todoList.collection != nil else {
	print("Missing collection from todo list \(todoList)")
	// Pop view since we can't invite a user. This must be done outside of the viewDidLoad.
	dispatch_async(dispatch_get_main_queue()) {
	self.dismissViewControllerAnimated(true) { }
	}
	return
	}
	initSearchController()
	loadContacts() {
	do {
	try Syncbase.startScanForUsersInNeighborhood(
	ScanNeighborhoodForUsersHandler(onFound: self.onFound, onLost: self.onLost))
	} catch {
	print("Unable to scan for other users: \(error)")
	}
	}
	}

	override func viewWillDisappear(animated: Bool) {
	Syncbase.stopAllScansForUsersInNeighborhood()
	}

	func initSearchController() {
	// Cannot be done in IB yet.
	searchController = UISearchController(searchResultsController: nil)
	searchController.delegate = self
	searchController.searchResultsUpdater = self
	searchController.dimsBackgroundDuringPresentation = false
	searchController.searchBar.sizeToFit()
	tableView.tableHeaderView = searchController.searchBar
	definesPresentationContext = true
	}

	// MARK: Address Book contacts

	func loadContacts(doneCallback: Void -> Void) {
	CNContactStore().requestAccessForEntityType(.Contacts) { (granted, error) in
	guard granted && error == nil else {
	print("Contants not able to load: granted=\(granted) error=\(error)")
	dispatch_async(dispatch_get_main_queue()) {
	self.disableContacts()
	doneCallback()
	}
	return
	}
	let request = CNContactFetchRequest(keysToFetch: Contact.keysToFetch)
	var results: [Contact] = []
	do {
	self.contactsByLowercaseEmailMu.lock()
	defer { self.contactsByLowercaseEmailMu.unlock() }
	// This is a bit slow loading everything at once. In a real app you want to take a more
	// advanced strategy, perhaps updating the UI in batches or some other methodology.
	try CNContactStore().enumerateContactsWithFetchRequest(request) { (cncontact, stop) in
	let contact = Contact(contact: cncontact)
	results.append(contact)
	if let emails = contact.emails {
	for email in emails {
	// The email was lowercased in the Contact class's init.
	self.contactsByLowercaseEmail[email] = contact
	}
	}
	}
	dispatch_async(dispatch_get_main_queue()) {
	self.didLoadContacts = true
	self.people[Category.Contacts.rawValue] = results
	self.tableView.reloadData()
	doneCallback()
	}
	} catch {
	print("Unable to fetch contacts: \(error)")
	dispatch_async(dispatch_get_main_queue()) {
	self.disableContacts()
	doneCallback()
	}
	}
	}
	}

	/// disableContacts is used when the user has not granted authorization to contacts or some other
	/// error has occured loading contacts. Must be called from main.
	func disableContacts() {
	didLoadContacts = false
	sectionNames[.Contacts] = nil
	sectionNames[.NearbyContacts] = nil
	people = [people[Category.Nearby.rawValue]]
	searchResults = [searchResults[Category.Nearby.rawValue]]
	tableView.reloadData()
	}

	// MARK: Tableview delegates

	override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
	if searchController.active && !searchResultsFound {
	// We only have one section in the case of the send email cell.
	return 1
	}
	return sectionNames.count
	}

	override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
	if searchController.active {
	if searchResultsFound {
	return searchResults[section].count
	} else {
	// We only have one row in the case of the send email cell.
	return 1
	}
	}
	return people[section].count
	}

	override func tableView(tableView: UITableView, willDisplayHeaderView view: UIView, forSection section: Int) {
	view.tintColor = UIColor.whiteColor()
	}

	override func tableView(tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
	if searchController.active && !searchResultsFound {
	// Don't show a section title if we're just showing send an email cell.
	return nil
	}
	return sectionNames[Category(rawValue: section)!]
	}

	override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
	// In the case where we have are searching and have found no results, offer the send email cell.
	if searchController.active && !searchResultsFound {
	// This cell is a prototype inside the Main.storyboard. Cannot fail.
	let cell = tableView.dequeueReusableCellWithIdentifier(sendEmailCell, forIndexPath: indexPath) as! SendEmailCell
	cell.emailLabel.text = searchController.searchBar.text
	return cell
	}

	// This cell is a prototype inside the Main.storyboard. Cannot fail.
	let cell = self.tableView.dequeueReusableCellWithIdentifier(personCellId, forIndexPath: indexPath) as! PersonCell
	if searchController.active {
	// Show search results.
	cell.contact = searchResults[indexPath.section][indexPath.row]
	} else {
	// Not searching, show entire list.
	cell.contact = people[indexPath.section][indexPath.row]
	}
	cell.updateView()
	return cell
	}

	override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
	if searchController.active && !searchResultsFound {
	return SendEmailCell.height
	}
	return PersonCell.height
	}

	// MARK: Inviting

	override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
	// No-op if can't create a person from index path.
	if let contact = contactAtIndexPath(indexPath) {
	do {
	try inviteContact(contact)
	} catch {
	print("Unable to invite \(contact): \(error)")
	let ac = UIAlertController(
	title: "Oops!",
	message: "Unable to send invite. Try again.",
	preferredStyle: .Alert)
	ac.addAction(UIAlertAction(title: "OK", style: .Default, handler: nil))
	presentViewController(ac, animated: true, completion: nil)
	return
	}
	// Dismiss the view.
	if searchController.active {
	// The search bar needs to close before we pop, so handle in didDismissSearch callback.
	shouldDismiss = true
	searchController.active = false
	} else {
	navigationController?.popViewControllerAnimated(true)
	}
	}
	}

	func contactAtIndexPath(indexPath: NSIndexPath) -> Contact? {
	// Determine if we entered an email or not. If email, validate email and construct a Person obj.
	var personToInvite: Contact?
	if let text = searchController.searchBar.text where searchController.active && !searchResultsFound {
	let validEmail = NSPredicate(format: "SELF MATCHES %@", emailRegEx).evaluateWithObject(text)
	if validEmail {
	// Create new person with this email.
	personToInvite = Contact(emails: [text])
	} else {
	// Invalid email, show alert.
	let alert = UIAlertController(title: "Invalid email",
	message: "Please enter a valid email",
	preferredStyle: .Alert)
	alert.addAction(UIAlertAction(title: "Ok", style: .Default, handler: nil))
	navigationController?.presentViewController(alert, animated: true, completion: nil)
	}
	} else if people.indices.contains(indexPath.section) &&
	people[indexPath.section].indices.contains(indexPath.row) {
	// We're inviting an existing Person.
	personToInvite = people[indexPath.section][indexPath.row]
	}
	return personToInvite
	}

	// This is called after selecting a contact if the search controller is active.
	func didDismissSearchController(searchController: UISearchController) {
	// If we were searching when we selected a person, we need to wait for its dismiss animation
	// to finish before popping the view.
	if shouldDismiss {
	navigationController?.popViewControllerAnimated(true)
	}
	}

	// inviteContact is the function responsible for actually inviting a user to the collection's
	// syncgroup.
	func inviteContact(contact: Contact) throws {
	if let user = contact.user {
	// Admin allows them to invite people to the syncgroup as well.
	try todoList.collection!.syncgroup().inviteUser(user, level: .READ_WRITE_ADMIN)
	} else if let emails = contact.emails {
	for email in emails {
	try todoList.collection!.syncgroup().inviteUser(User(alias: email), level: .READ_WRITE_ADMIN)
	}
	}
	}

	// MARK: Discovery

	func onFound(user: User) {
	dispatch_async(dispatch_get_global_queue(QOS_CLASS_BACKGROUND, 0)) {
	// Determine if they're an existing contact.
	self.contactsByLowercaseEmailMu.lock()
	defer { self.contactsByLowercaseEmailMu.unlock() }
	var contact = Contact(user: user)
	var section = Category.Nearby.rawValue
	if let existingContact = self.contactsByLowercaseEmail[user.alias.lowercaseString] {
	contact = existingContact
	contact.user = user
	section = Category.NearbyContacts.rawValue
	}
	// If we were never able to load contacts, then they should be disabled and we only have 1
	// section.
	if !self.didLoadContacts {
	section = 0
	}
	dispatch_async(dispatch_get_main_queue()) {
	self.people[section].append(contact)
	self.people[section].sortInPlace { (lhs, rhs) -> Bool in
	return lhs.description.compare(rhs.description) == NSComparisonResult.OrderedAscending
	}
	self.tableView.reloadSections(NSIndexSet(index: section), withRowAnimation: .Automatic)
	}
	}
	}

	func onLost(user: User) {
	for section in nearbySections {
	if let idx = people[section].indexOf({ $0.user == user }) {
	people[section].removeAtIndex(idx)
	tableView.reloadSections(NSIndexSet(index: section), withRowAnimation: .Automatic)
	break
	}
	}
	}

	var nearbySections: [Int] {
	if didLoadContacts {
	return [Category.NearbyContacts.rawValue, Category.Nearby.rawValue]
	}
	return [0]
	}
	}

	// MARK: Search

	// Filters people to match the text user searched for.
	extension InviteViewController: UISearchControllerDelegate, UISearchResultsUpdating {
	func updateSearchResultsForSearchController(searchController: UISearchController) {
	if let searchText = searchController.searchBar.text where searchText.characters.count > 0 {
	for section in nearbySections {
	searchResults[section] = people[section].filter { contact -> Bool in
	return contact.description.rangeOfString(searchText,
	options: .CaseInsensitiveSearch,
	range: contact.description.startIndex ..< contact.description.endIndex,
	locale: nil) != nil
	}
	}
	if didLoadContacts {
	searchResults[Category.Contacts.rawValue] = []
	if let contacts = try? CNContactStore().unifiedContactsMatchingPredicate(
	CNContact.predicateForContactsMatchingName(searchText),
	keysToFetch: Contact.keysToFetch) {
	searchResults[Category.Contacts.rawValue] = contacts.map { Contact(contact: $0) }
	}
	}
	} else {
	for i in 0 ..< searchResults.count {
	searchResults[i] = []
	}
	}
	searchResultsFound = false
	for section in searchResults {
	if !section.isEmpty {
	searchResultsFound = true
	break
	}
	}
	tableView.reloadData()
	}
	}

	// MARK: Tableview Cells

	// Displays a person with name and their profile photo.
	class PersonCell: UITableViewCell {
	static let height: CGFloat = 44
	@IBOutlet weak var nameLabel: UILabel!
	var contact: Contact?

	func updateView() {
	nameLabel.text = contact?.description
	}
	}

	// Display a cell that shows the email the invite will be sent to.
	class SendEmailCell: UITableViewCell {
	static let height: CGFloat = 74
	@IBOutlet weak var emailLabel: UILabel!
	}