SwiftUI Color Extension - contrasting for text on background

ColorExtension.swift

extension Color {
    static var forExampleMyDarkRed: Color {
        return Color(hue: 1.0, saturation: 1.0, brightness: 0.6, opacity: 0.8)
    }

    init(hex: String) {
        let scanner = Scanner(string: hex)
        _ = scanner.scanString("#") // Skip the '#' prefix if present

        var rgb: UInt64 = 0
        scanner.scanHexInt64(&rgb)

        let r = Double((rgb & 0xFF0000) >> 16) / 255.0
        let g = Double((rgb & 0x00FF00) >> 8) / 255.0
        let b = Double(rgb & 0x0000FF) / 255.0

        self.init(red: r, green: g, blue: b, opacity: 1.0)
    }

    func toHex2() -> String {

        return self.description

    }

    func isLight() -> Bool {
        let components = self.cgColor?.components
        let h = (components?[0] ?? 0) * 299
        let v = (components?[1] ?? 0) * 587
        let b = components?[2] ?? 0
        let brightness = (h + v + (b) * 114) / 1000
        return brightness > 0.5
    }

    func contrastingColor() -> Color {
        return self.isLight() ? .black : .white
    }

    static let customPurple = Color(red: 128/255, green: 0/255, blue: 128/255)
    static let customTeal = Color(red: 0/255, green: 128/255, blue: 128/255)

    static var tone0: Color { Color(hex: "000000") }
    static var tone10: Color { Color(hex: "1A1A1A") }
    static var tone20: Color { Color(hex: "333333") }
    static var tone30: Color { Color(hex: "4D4D4D") }
    static var tone40: Color { Color(hex: "676767") }
    static var tone50: Color { Color(hex: "808080") }
    static var tone60: Color { Color(hex: "999999") }
    static var tone70: Color { Color(hex: "B3B3B3") }
    static var tone80: Color { Color(hex: "CCCCCC") }
    static var tone90: Color { Color(hex: "E6E6E6") }
    static var tone95: Color { Color(hex: "F2F2F2") }
    static var tone99: Color { Color(hex: "FAFAFA") }
    static var tone100: Color { Color(hex: "FFFFFF") }
}

Palette.swift

import SwiftUI

struct TonalPalette: Identifiable {
    let id = UUID()
    let name: String
    let colors: [TonalColor]
}

// make this conform to hashable
final class TonalColor: Hashable {
    var id: UUID
    var tonalColor: Color

    init(id: UUID = UUID() ,tonalColor: Color) {
        self.id = id
        self.tonalColor = tonalColor
    }

    static func == (lhs: TonalColor, rhs: TonalColor) -> Bool {
        lhs.id == rhs.id
    }

    func hash(into hasher: inout Hasher) {
        hasher.combine(id)
    }
}

// MARK: - ViewModel

class PaletteChoices: ObservableObject {
    static let shared = PaletteChoices()

    @Published var palettes: [TonalPalette] = []

    private init() {
        loadPalettes()
    }

    private func loadPalettes() {
        palettes = [
            TonalPalette(name: "Purple", colors: [
                TonalColor(tonalColor: Color.tone0),
                TonalColor(tonalColor: Color.tone10),
                TonalColor(tonalColor: Color.tone20),
                TonalColor(tonalColor: Color.tone30),
                TonalColor(tonalColor: Color.tone40),
                TonalColor(tonalColor: .yellow.opacity(0.5)),
                TonalColor(tonalColor: Color.tone50),
                TonalColor(tonalColor: Color.tone60),
                TonalColor(tonalColor: Color.tone70.opacity(0.9)),
                TonalColor(tonalColor: Color.tone80),
                TonalColor(tonalColor: .purple.opacity(0.5)),
                TonalColor(tonalColor: Color.tone95),
                TonalColor(tonalColor: Color.tone99),
                TonalColor(tonalColor: Color.tone100),
            ]),
            TonalPalette(name: "Teal", colors: [
                TonalColor(tonalColor: .teal.opacity(0.1)),
                TonalColor(tonalColor: Color.tone10),
                TonalColor(tonalColor: .teal.opacity(0.2)),
                TonalColor(tonalColor: .teal.opacity(0.3)),
                TonalColor(tonalColor: .teal.opacity(0.4)),
                TonalColor(tonalColor: .teal.opacity(0.5)),
                TonalColor(tonalColor: .teal.opacity(0.6)),
                TonalColor(tonalColor: .teal.opacity(0.7)),
                TonalColor(tonalColor: .teal.opacity(0.8)),
                TonalColor(tonalColor: .teal.opacity(0.9)),
                TonalColor(tonalColor: .teal)
            ]),
            // Add more palettes here...
        ]
    }
}

#Preview("Palette") {
    VStack() {
        HStack(alignment: .center) {
            ContentView()
                .frame(width: 320, height: 280)
        }
    }
}

struct ContentView: View {
    @StateObject private var paletteChoices = PaletteChoices.shared

    var body: some View {
        List {
            ForEach(paletteChoices.palettes) { palette in
                Section(header: Text(palette.name)
                    .foregroundColor(Color.accentColor)
                    .font(.title2)) {
                        ForEach(palette.colors, id: \.self) { color in
                            Text("\(color.tonalColor.toHex2())")
                                .font(.caption)
                                .containerShape(Rectangle())
                                .frame(width: 90, height: 30)
                                .background(color.tonalColor)
                                .foregroundColor(color.tonalColor.contrastingColor())
                        }
                }
            }
        }
    }
}