/*

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

    See LICENSE.txt for this sample’s licensing information

    Abstract:

    A view controller that lists recent payments made with our app.

*/

import UIKit

import PaymentsFramework

class PaymentHistoryViewController: UITableViewController {

    private let paymentProvider = PaymentProvider()

    private var payments = [Payment]() {

        didSet {

            // If a new array of `Payment`s has been set, reload the table view.

            guard oldValue != payments && isViewLoaded else { return }

            tableView.reloadData()

        }

    }

    /// Used to format payment amounts in table view cells.

    private var amountFormatter: NumberFormatter = {

        let formatter = NumberFormatter()

        formatter.numberStyle = .currency

        return formatter

    }()

    /// Used to format payment dates in table view cells.

    private var dateFormatter: DateFormatter = {

        let formatter = DateFormatter()

        formatter.dateStyle = .short

        formatter.timeStyle = .short

        return formatter

    }()

    // MARK: UIViewController

    override func viewWillAppear(_ animated: Bool) {

        super.viewWillAppear(animated)

        payments = paymentProvider.loadPaymentHistory().reversed()

    }

    // MARK: UITableViewDataSource

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

        return payments.count

    }

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

        guard let cell = tableView.dequeueReusableCell(withIdentifier: PaymentTableViewCell.reuseIdentifier, for: indexPath) as? PaymentTableViewCell else { fatalError("Unable to dequeue a PaymentTableViewCell") }

        let payment = payments[indexPath.row]

        // Configure the cell with the payment details.

        cell.contactLabel.text = payment.contact.formattedName

        if let date = payment.date {

            cell.dateLabel.text = dateFormatter.string(from: date)

        }

        else {

            cell.dateLabel.text = "-"

        }

        amountFormatter.currencyCode = payment.currencyCode

        cell.amountLabel.text = amountFormatter.string(from: payment.amount)

        return cell

    }

}

/// Used by `PaymentHistoryViewController` to show details of a `Payment`.

class PaymentTableViewCell: UITableViewCell {

    static let reuseIdentifier = "PaymentTableViewCell"

    @IBOutlet weak var contactLabel: UILabel!

    @IBOutlet weak var dateLabel: UILabel!

    @IBOutlet weak var amountLabel: UILabel!

}