/*

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

    See LICENSE.txt for this sample’s licensing information

    Abstract:

    A state used to represent the `TaskBot` when being zapped by a `PlayerBot` attack.

*/

import SpriteKit

import GameplayKit

class TaskBotZappedState: GKState {

    // MARK: Properties

    unowned var entity: TaskBot

    /// The amount of time the `TaskBot` has been in its "zapped" state.

    var elapsedTime: TimeInterval = 0.0

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

    var animationComponent: AnimationComponent {

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

        return animationComponent

    }

    // MARK: Initializers

    required init(entity: TaskBot) {

        self.entity = entity

    }

    // MARK: GKState Life Cycle

    override func didEnter(from previousState: GKState?) {

        super.didEnter(from: previousState)

        // Reset the elapsed time.

        elapsedTime = 0.0

        // Check if the `TaskBot` has a movement component. (`GroundBot`s do, `FlyingBot`s do not.)

        if let movementComponent = entity.component(ofType: MovementComponent.self) {

            // Clear any pending movement.

            movementComponent.nextTranslation = nil

            movementComponent.nextRotation = nil

        }

        // Request the "zapped" animation for this `TaskBot`.

        animationComponent.requestedAnimationState = .zapped

    }

    override func update(deltaTime seconds: TimeInterval) {

        super.update(deltaTime: seconds)

        elapsedTime += seconds

        /*

            If the `TaskBot` has become "good" or has been in the current state long enough,

            re-enter `TaskBotAgentControlledState`.

        */

        if entity.isGood || elapsedTime >= GameplayConfiguration.TaskBot.zappedStateDuration {

            stateMachine?.enter(TaskBotAgentControlledState.self)

        }

    }

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

        switch stateClass {

            case is TaskBotZappedState.Type:

                /*

                    Reset the elapsed time the `taskBot` has been in `TaskBotZappedState`. This ensures

                    there is a delay from when a `taskBot` stops being zapped to when it becomes

                    agent controlled.

                */

                elapsedTime = 0.0

                return false

            case is TaskBotAgentControlledState.Type, is FlyingBotBlastState.Type:

                return true

            default:

                return false

        }

    }

}