/*

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

    See LICENSE.txt for this sample’s licensing information

    Abstract:

    An extension on `BaseScene` to manage the recording of a level's gameplay with `ReplayKit`. This extension is only included in the iOS version of the project.

*/

import ReplayKit

extension BaseScene: RPPreviewViewControllerDelegate, RPScreenRecorderDelegate {

    // MARK: Computed Properties

    var screenRecordingToggleEnabled: Bool {

        return UserDefaults.standard.bool(forKey: screenRecorderEnabledKey)

    }

    // MARK: Start/Stop Screen Recording

    func startScreenRecording() {

        // Do nothing if screen recording hasn't been enabled.

        guard screenRecordingToggleEnabled else { return }

        let sharedRecorder = RPScreenRecorder.shared()

        // Register as the recorder's delegate to handle errors.

        sharedRecorder.delegate = self

        sharedRecorder.startRecording() { error in

            if let error = error {

                self.showScreenRecordingAlert(message: error.localizedDescription)

            }

        }

    }

    func stopScreenRecording(withHandler handler:@escaping (() -> Void)) {

        let sharedRecorder = RPScreenRecorder.shared()

        sharedRecorder.stopRecording { previewViewController, error in

            if let error = error {

                // If an error has occurred, display an alert to the user.

                self.showScreenRecordingAlert(message: error.localizedDescription)

                return

            }

            if let previewViewController = previewViewController {

                // Set delegate to handle view controller dismissal.

                previewViewController.previewControllerDelegate = self

                /*

                    Keep a reference to the `previewViewController` to

                    present when the user presses on preview button.

                */

                self.previewViewController = previewViewController

            }

            handler()

        }

    }

    func showScreenRecordingAlert(message: String) {

        // Pause the scene and un-pause after the alert returns.

        isPaused = true

        // Show an alert notifying the user that there was an issue with starting or stopping the recorder.

        let alertController = UIAlertController(title: "ReplayKit Error", message: message, preferredStyle: .alert)

        let alertAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.`default`) { _ in

            self.isPaused = false

        }

        alertController.addAction(alertAction)

        /*

            `ReplayKit` event handlers may be called on a background queue. Ensure

            this alert is presented on the main queue.

        */

        DispatchQueue.main.async() {

            self.view?.window?.rootViewController?.present(alertController, animated: true, completion: nil)

        }

    }

    func discardRecording() {

        // When we no longer need the `previewViewController`, tell `ReplayKit` to discard the recording and nil out our reference

        RPScreenRecorder.shared().discardRecording {

            self.previewViewController = nil

        }

    }

    // MARK: RPScreenRecorderDelegate

    func screenRecorder(_ screenRecorder: RPScreenRecorder, didStopRecordingWithError error: Error, previewViewController: RPPreviewViewController?) {

        // Display the error the user to alert them that the recording failed.

        showScreenRecordingAlert(message: error.localizedDescription)

        /// Hold onto a reference of the `previewViewController` if not nil.

        if previewViewController != nil {

            self.previewViewController = previewViewController

        }

    }

    // MARK: RPPreviewViewControllerDelegate

    func previewControllerDidFinish(previewController: RPPreviewViewController) {

        previewViewController?.dismiss(animated: true, completion: nil)

    }

}