extension BoxOfficeEntity {
    struct BoxOfficeResult: Decodable {
        let boxOfficeType, showRange: String
        let dailyBoxOfficeList: [DailyBoxOffice]

        enum CodingKeys: String, CodingKey {
            case boxOfficeType = "boxofficeType"
            case showRange, dailyBoxOfficeList
        }
    }
}

func decode<T: Decodable>(_ data: Data?) throws -> T {
    guard let data = data,
          let decodedData = try? decoder.decode(T.self, from: data) else {
        throw DecodingError.decodingFailure
    }
    return decodedData
}

private let collectionView: UICollectionView = {
    let configuration = UICollectionLayoutListConfiguration(appearance: .plain)
    let layout = UICollectionViewCompositionalLayout.list(using: configuration)
...
}
    
private var dataSource: UICollectionViewDiffableDataSource<NetworkNamespace, BoxOfficeEntity.BoxOfficeResult.DailyBoxOffice>?
...
    

private let calendarView: UICalendarView = {
        var calendarView = UICalendarView()
        calendarView.translatesAutoresizingMaskIntoConstraints = false
        calendarView.backgroundColor = .systemBackground
        
        let endDate = Calendar.current.date(byAdding: .day, value: -1, to: Date()) ?? Date()
        let calendarViewDateRange = DateInterval(start: Date(timeIntervalSince1970: 0), end: endDate)
        calendarView.availableDateRange = calendarViewDateRange
        
        return calendarView
    }()

private let indicatorView: UIActivityIndicatorView = {
    let indicatorView = UIActivityIndicatorView()
    indicatorView.style = .large
    indicatorView.translatesAutoresizingMaskIntoConstraints = false

    return indicatorView
}()

private var isLoading: Bool = true {
    willSet(newValue) {
        if newValue == true {
            indicatorView.isHidden = false
            indicatorView.startAnimating()
        } else {
            indicatorView.isHidden = true
            indicatorView.stopAnimating()
        }
    }
}

collectionView.refreshControl = refreshControl
    refreshControl.addTarget(self, action: #selector(refresh), for: .valueChanged)

let modeChangeButton = UIBarButtonItem(title: "화면 모드 변경", style: .plain, target: self, action: #selector(hitChangeModeButton))
let flexibleSpace = UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: self, action: nil)
...
self.toolbarItems = [flexibleSpace, modeChangeButton, flexibleSpace]

@objc func hitChangeModeButton() {
    let mode: String = isListMode == true ? "아이콘" : "리스트"
    let alert = UIAlertController(title: "화면 모드 변경", message: nil, preferredStyle: .actionSheet)
    let modeChangeAction = UIAlertAction(title: mode, style: .default) { _ in
        self.isListMode.toggle()
    }
    let cancelAction = UIAlertAction(title: "취소", style: .cancel)
        
    alert.addAction(modeChangeAction)
    alert.addAction(cancelAction)
    present(alert, animated: true)
}

attributedString.addAttribute(.foregroundColor, value: UIColor.systemRed, range: (fixedIntensity as NSString).range(of: "▲"))

private let audienceLabel: UILabel = {
    let label = UILabel()
    label.font = .preferredFont(forTextStyle: .body)
    label.translatesAutoresizingMaskIntoConstraints = false
    label.adjustsFontForContentSizeCategory = true
    label.adjustsFontSizeToFitWidth = true

    return label
}()