用于配色方案的Swift扩展和枚举

import UIKit

extension UIColor {
    static let primary = UIColor(red: 0.2, green: 0.4, blue: 0.6, alpha: 1.0)
    static let secondary = UIColor(red: 0.8, green: 0.6, blue: 0.4, alpha: 1.0)
    static let accent = UIColor(red: 0.6, green: 0.2, blue: 0.4, alpha: 1.0)
}

enum ColorScheme {
    case light
    case dark
    
    var backgroundColor: UIColor {
        switch self {
        case .light:
            return .white
        case .dark:
            return .black
        }
    }
    
    var textColor: UIColor {
        switch self {
        case .light:
            return .black
        case .dark:
            return .white
        }
    }
    
    var primaryColor: UIColor {
        switch self {
        case .light:
            return .primary
        case .dark:
            return .secondary
        }
    }
    
    var secondaryColor: UIColor {
        switch self {
        case .light:
            return .secondary
        case .dark:
            return .primary
        }
    }
}

let currentColorScheme = ColorScheme.light
let backgroundColor = currentColorScheme.backgroundColor
let textColor = currentColorScheme.textColor
let primaryColor = currentColorScheme.primaryColor
let secondaryColor = currentColorScheme.secondaryColor