/*

    Copyright (C) 2016 Apple Inc. All Rights Reserved.

    See LICENSE.txt for this sample’s licensing information

    Abstract:

    A view controller that lists all generic password keychain items who's service and access group match those specified in `KeychainConfiguration`.

*/

import UIKit

class AccountsViewController: UITableViewController {

    let cellReuseIdentifier = "Cell"

    var passwordItems = [KeychainPasswordItem]()

    // MARK: UIViewController

    override func viewDidLoad() {

        super.viewDidLoad()

        // Localize the title using app-specific localizations.

        navigationItem.title = NSLocalizedString("AccountsViewControllerTitle", comment: "")

    }

    override func viewWillAppear(_ animated: Bool) {

        super.viewWillAppear(animated)

        /*

            Make sure the table view is up-to-date by first reloading the

            password items from the keychain and then reloading the table view.

        */

        do {

            passwordItems = try KeychainPasswordItem.passwordItems(forService: KeychainConfiguration.serviceName, accessGroup: KeychainConfiguration.accessGroup)

        }

        catch {

            fatalError("Error fetching password items - \(error)")

        }

        tableView.reloadData()

    }

    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {

        super.prepare(for: segue, sender: sender)

        if let navigationController = segue.destination as? UINavigationController,

                let accountViewController = navigationController.childViewControllers.first as? AccountDetailsViewController,

                let indexPath = tableView.indexPathForSelectedRow {

            /*

                Set the account name on the `AccountDetailsViewController` that

                is about to be displayed to the account name of the selected cell.

            */

            let passwordItem = passwordItems[indexPath.row]

            accountViewController.accountName = passwordItem.account

        }

    }

    // MARK: Unwind segues

    @IBAction func unwindToAccountsView(_ segue: UIStoryboardSegue) {

    }

    // MARK: UITableViewDataSource

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {

        return passwordItems.count

    }

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

        let cell = tableView.dequeueReusableCell(withIdentifier: cellReuseIdentifier, for: indexPath)

        let passwordItem = passwordItems[indexPath.row]

        cell.textLabel?.text = passwordItem.account

        return cell

    }

    // MARK: UITableViewDataDelegate

    override func tableView(_ tableView: UITableView, editActionsForRowAt indexPath: IndexPath) -> [UITableViewRowAction]? {

        let deleteAction = UITableViewRowAction(style: .default, title: "Delete") { action, indexPath in

            // Try to delete the item from the keychain.

            let passwordItem = self.passwordItems[indexPath.row]

            do {

                try passwordItem.deleteItem()

            }

            catch {

                fatalError("Error deleting keychain item - \(error)")

            }

            // Delete the item from the `passwordItems` array.

            self.passwordItems.remove(at: indexPath.row)

            // Delete the item from the table view

            self.tableView.deleteRows(at: [indexPath], with: .automatic)

        }

        return [deleteAction]

    }

}