/*

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

 See LICENSE.txt for this sample’s licensing information

 Abstract:

 The delegate that handles creating a new chat (including taking a photo from the camera).

 */

import UIKit

class NewChatDelegate: NSObject, UIImagePickerControllerDelegate, UINavigationControllerDelegate {

    static func isCameraAvailable() -> Bool {

        return UIImagePickerController.isSourceTypeAvailable(.camera)

    }

    private weak var presentingViewController: UIViewController?

    private let recipient: Friend?

    private let completion: (UIImage?) -> Void

    init(presentingViewController: UIViewController, recipient: Friend?, completion: @escaping (UIImage?) -> Void) {

        self.presentingViewController = presentingViewController

        self.recipient = recipient

        self.completion = completion

    }

    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {

        picker.dismiss(animated: true) {

            let chatImage = info[UIImagePickerControllerEditedImage] as? UIImage ?? info[UIImagePickerControllerOriginalImage] as? UIImage

            // Since AppChat isn't a real chat app yet, we'll just present an alert to simulate the rest.

            let alert = UIAlertController(title: self.alertTitle(for: self.recipient), message: self.alertMessage(for: self.recipient), preferredStyle: .alert)

            let okAction = UIAlertAction(title: NSLocalizedString("OK", comment: "OK string"), style: .default) { (_) -> Void in

                self.completion(chatImage)

            }

            alert.addAction(okAction)

            self.presentingViewController?.present(alert, animated: true)

        }

    }

    func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {

        picker.dismiss(animated: true) { 

            self.completion(nil)

        }

    }

    private func alertTitle(for recipient: Friend?) -> String {

        if let friend = recipient {

            let format = NSLocalizedString("Chat Sent to %@", comment: "Format string for a chat sent to a friend")

            return String(format: format, friend.name)

        }

        else {

            return NSLocalizedString("Choose a Friend", comment: "Choose a friend as the chat recipient")

        }

    }

    private func alertMessage(for recipient: Friend?) -> String {

        if let friend = recipient {

            let format = NSLocalizedString("This is where we'd send the chat to your friend %@. But AppChat isn't a real chat app yet, so use your imagination!", comment: "Message when sending a new chat with a recipient, the friend name is substituted for the format specifier")

            return String(format: format, friend.name)

        }

        else {

            return NSLocalizedString("This is where you'd choose a friend, and then we'd send the chat to them. But AppChat isn't a real chat app yet, so use your imagination!", comment: "Message when sending a new chat without a recipient")

        }

    }

}