//: Playground - noun: a place where people can play

import UIKit

var str = "Hello, playground"

let searchController = UISearchController(searchResultsController: nil)


//in viewdidload
searchController.searchBar.tintColor = .white
searchController.searchBar.barTintColor = .white
searchController.searchResultsUpdater = self
searchController.searchBar.keyboardAppearance = .dark
searchController.definesPresentationContext = false
searchController.dimsBackgroundDuringPresentation = false
UIBarButtonItem.appearance(whenContainedInInstancesOf: [UISearchBar.self] ).tintColor = UIColor.white
if #available(iOS 11.0, *) {
    self.navigationItem.searchController = searchController
} else {
    //            self.navigationItem.titleView = searchController.searchBar
    // Fallback on earlier versions
}



extension ViewController: UISearchResultsUpdating {
    func updateSearchResults(for searchController: UISearchController) {
        let oldFilteredNames = self.filteredGuests

        if (searchController.searchBar.text?.isEmpty)! {
            self.filteredGuests = guests
        } else {
            self.filteredGuests = guests.filter({ (user) -> Bool in
                return (user.name ?? "").lowercased().contains(searchController.searchBar.text!.lowercased()) || (user.surname ?? "").lowercased().contains(searchController.searchBar.text!.lowercased())
            })
        }

        self.collectionView.performBatchUpdates({
            for (oldIndex, oldUser) in oldFilteredNames.enumerated() {
                if self.filteredGuests.contains(oldUser) == false {
                    let indexPath = IndexPath(item: oldIndex, section: 0)
                    self.collectionView.deleteItems(at: [indexPath])
                }
            }

            for (index, name) in self.filteredGuests.enumerated() {
                if oldFilteredNames.contains(name) == false {
                    let indexPath = IndexPath(item: index, section: 0)
                    self.collectionView.insertItems(at: [indexPath])
                }
            }
        }, completion: nil)
    }
}