/*

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

    See LICENSE.txt for this sample’s licensing information

    Abstract:

    A state used to represent the player when immobilized by `TaskBot` attacks.

*/

import SpriteKit

import GameplayKit

class PlayerBotRechargingState: GKState {

    // MARK: Properties

    unowned var entity: PlayerBot

    /// The amount of time the `PlayerBot` has been in the "recharging" 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 PlayerBotRechargingState's entity must have an AnimationComponent.") }

        return animationComponent

    }

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

    var chargeComponent: ChargeComponent {

        guard let chargeComponent = entity.component(ofType: ChargeComponent.self) else { fatalError("A PlayerBotRechargingState's entity must have a ChargeComponent.") }

        return chargeComponent

    }

    // MARK: Initializers

    required init(entity: PlayerBot) {

        self.entity = entity

    }

    // MARK: GKState life cycle

    override func didEnter(from previousState: GKState?) {

        super.didEnter(from: previousState)

        // Reset the recharge duration when entering this state.

        elapsedTime = 0.0

        // Request the "inactive" animation for the `PlayerBot`.

        animationComponent.requestedAnimationState = .inactive

    }

    override func update(deltaTime seconds: TimeInterval) {

        super.update(deltaTime: seconds)

        // Update the elapsed recharge duration.

        elapsedTime += seconds

        /**

            There is a delay from when the `PlayerBot` enters this state to when it begins to recharge.

            Do nothing if the `PlayerBot` hasn't been in this state long enough.

        */

        if elapsedTime < GameplayConfiguration.PlayerBot.rechargeDelayWhenInactive { return }

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

        let chargeComponent = self.chargeComponent

        // Add charge to the `PlayerBot`.

        let amountToRecharge = GameplayConfiguration.PlayerBot.rechargeAmountPerSecond * seconds

        chargeComponent.addCharge(chargeToAdd: amountToRecharge)

        // If the `PlayerBot` is fully charged it can become player controlled again.

        if chargeComponent.isFullyCharged {

            entity.isPoweredDown = false

            stateMachine?.enter(PlayerBotPlayerControlledState.self)

        }

    }

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

        return stateClass is PlayerBotPlayerControlledState.Type

    }

}