//
//  AccountServiceResources.swift
//  Wallet
//
//  Created by Igor on 05.03.2021.
//  Copyright © 2021 AM. All rights reserved.
//

import Foundation
import WalletFoundation
import WalletKit

private let freeKey = CommonKey("Account.Service.Resources.free")
private let paidKey = CommonKey("Account.Service.Resources.paid")
private let isEnabledKey = CommonKey("Account.Service.Resources.isEnabled")

extension Notification.Name {
    static let didUpdateAccountQuota = Self("Account.Service.Resources.didUpdateAccountQuota")
}

extension Account.Service {
    final class CommonResources {
        
        private var service: Resources.Service.Quota?

        private(set) var free: Int {
            get { Settings.shared[freeKey] }
            set { Settings.shared[freeKey] = newValue }
        }
        
        private(set) var paid: Int {
            get { Settings.shared[paidKey] }
            set { Settings.shared[paidKey] = newValue }
        }
        
        var count: Int { self.free + self.paid }

        var isEmpty: Bool { !self.service.isExist && self.free == 0 && self.paid == 0 }

        var isEnabled: Bool {
            get { Settings.shared[isEnabledKey] }
            set {
                Settings.shared[isEnabledKey] = newValue
                Notification.post(name: .didUpdateAccountQuota)
            }
        }

        init() {
            if !Settings.shared.contains(isEnabledKey) {
                self.isEnabled = true
            }
        }
        
        func update(free: Int, paid: Int) {
            self.free = free
            self.paid = paid
            Notification.post(name: .didUpdateAccountQuota)
            
        }

        func fetch(using account: WalletKit.Wallet?, clear: Bool = false, force: Bool = false) {
            if clear {
                self.paid = 0
                self.free = 0
                self.service = nil
                Notification.post(name: .didUpdateAccountQuota)
            }
            
            guard let account, !account.name.isEmpty else { return }
            
            self.perform(using: account)
            if force {
                delayed(4) { self.perform(using: account) }
                delayed(8) { self.perform(using: account) }
                delayed(16) { self.perform(using: account) }
            }
        }

        private func perform(using account: WalletKit.Wallet) {
            
            if let service = self.service {
                if service.account != account.name {
                    self.service = .init(account: account.name)
                }
            } else {
                self.service = .init(account: account.name)
            }
            
            self.service >>- { service in
                service.fetch { [weak self] _ in
                    if let free = service.free,
                       let paid = service.paid {
                        self?.update(free: free, paid: paid)
                    }
                }
            }
            
        }
    }
}