/*

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

    See LICENSE.txt for this sample’s licensing information

    Abstract:

    The base class for a `LevelScene`'s Pause, Fail, and Success states. Handles the task of loading and displaying a full-screen overlay from a scene file when the state is entered.

*/

import SpriteKit

import GameplayKit

class LevelSceneOverlayState: GKState {

    // MARK: Properties

    unowned let levelScene: LevelScene

    /// The `SceneOverlay` to display when the state is entered.

    var overlay: SceneOverlay!

    /// Overridden by subclasses to provide the name of the .sks file to load to show as an overlay.

    var overlaySceneFileName: String { fatalError("Unimplemented overlaySceneName") }

    // MARK: Initializers

    init(levelScene: LevelScene) {

        self.levelScene = levelScene

        super.init()

        overlay = SceneOverlay(overlaySceneFileName: overlaySceneFileName, zPosition: WorldLayer.top.rawValue)

        /*

            Set the level preview image to the image for this state's level if this state

            has a "view recorded content" button, with a child node called "levelPreview".

        */

        if let viewRecordedContentButton = button(withIdentifier: .viewRecordedContent), let levelPreviewNode = viewRecordedContentButton.childNode(withName: "levelPreview") as? SKSpriteNode {

            levelPreviewNode.texture = SKTexture(imageNamed: levelScene.levelConfiguration.fileName)

        }

    }

    // MARK: GKState Life Cycle

    override func didEnter(from previousState: GKState?) {

        super.didEnter(from: previousState)

        #if os(iOS)

        // Show the appropriate state for the recording buttons.

        button(withIdentifier: .screenRecorderToggle)?.isSelected = levelScene.screenRecordingToggleEnabled

        if self is LevelSceneSuccessState || self is LevelSceneFailState {

            if let viewRecordedContentButton = button(withIdentifier: .viewRecordedContent) {

                viewRecordedContentButton.isHidden = true

                // Stop screen recording and update view recorded content button when complete.

                levelScene.stopScreenRecording() {

                    // Only show the view button if the recording is enabled and there's a valid `previewViewController` to present.

                    let recordingEnabledAndPreviewAvailable = self.levelScene.screenRecordingToggleEnabled && self.levelScene.previewViewController != nil

                    viewRecordedContentButton.isHidden = !recordingEnabledAndPreviewAvailable

                }

            }

        }

        #else

        // Hide replay buttons on OSX and tvOS.

        button(withIdentifier: .screenRecorderToggle)?.isHidden = true

        button(withIdentifier: .viewRecordedContent)?.isHidden = true

        #endif

        // Provide the levelScene with a reference to the overlay node.

        levelScene.overlay = overlay

    }

    override func willExit(to nextState: GKState) {

        super.willExit(to: nextState)

        levelScene.overlay = nil

        #if os(iOS)

        if self is LevelSceneSuccessState || self is LevelSceneFailState {

            // After leaving this state, we should discard the recording.

            levelScene.discardRecording()

        }

        #endif

    }

    // MARK: Convenience

    func button(withIdentifier identifier: ButtonIdentifier) -> ButtonNode? {

        return overlay.contentNode.childNode(withName: "//\(identifier.rawValue)") as? ButtonNode

    }

}