/*

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

    See LICENSE.txt for this sample’s licensing information

    Abstract:

    A state used to represent the `PlayerBot` when ready for control input from the player.

*/

import SpriteKit

import GameplayKit

class PlayerBotPlayerControlledState: GKState {

    // MARK: Properties

    unowned var entity: PlayerBot

    /// The `AnimationComponent` associated with the `entity`.

    var animationComponent: AnimationComponent {

        guard let animationComponent = entity.component(ofType: AnimationComponent.self) else { fatalError("A PlayerBotPlayerControlledState's entity must have an AnimationComponent.") }

        return animationComponent

    }

    /// The `MovementComponent` associated with the `entity`.

    var movementComponent: MovementComponent {

        guard let movementComponent = entity.component(ofType: MovementComponent.self) else { fatalError("A PlayerBotPlayerControlledState's entity must have a MovementComponent.") }

        return movementComponent

    }

    /// The `InputComponent` associated with the `entity`.

    var inputComponent: InputComponent {

        guard let inputComponent = entity.component(ofType: InputComponent.self) else { fatalError("A PlayerBotPlayerControlledState's entity must have an InputComponent.") }

        return inputComponent

    }

    // MARK: Initializers

    required init(entity: PlayerBot) {

        self.entity = entity

    }

    // MARK: GKState Life Cycle

    override func didEnter(from previousState: GKState?) {

        super.didEnter(from: previousState)

        // Turn on controller input for the `PlayerBot` when entering the player-controlled state.

        inputComponent.isEnabled = true

    }

    override func update(deltaTime seconds: TimeInterval) {

        super.update(deltaTime: seconds)

        /*

            Assume an animation of "idle" that can then be overwritten by the movement

            component in response to user input.

        */

        animationComponent.requestedAnimationState = .idle

    }

    override func isValidNextState(_ stateClass: AnyClass) -> Bool {

        switch stateClass {

            case is PlayerBotHitState.Type, is PlayerBotRechargingState.Type:

                return true

            default:

                return false

        }

    }

    override func willExit(to nextState: GKState) {

        super.willExit(to: nextState)

        // Turn off controller input for the `PlayerBot` when leaving the player-controlled state.

        entity.component(ofType: InputComponent.self)?.isEnabled = false

        // `movementComponent` is a computed property. Declare a local version so we don't compute it multiple times.

        let movementComponent = self.movementComponent

        // Cancel any planned movement or rotation when leaving the player-controlled state.

        movementComponent.nextTranslation = nil

        movementComponent.nextRotation = nil

    }

}