UI Prototyping with Coding Agents in Xcode

import SwiftUI

// MARK: - Sample Data (keep in its own file for reuse across prototypes)
struct BookClubSampleData {
    static let currentBook = "The Remains of the Day"
    static let members = ["Alice", "Ben", "Clara", "Dan", "Eva"]
    static let nextMeeting = "Thursday, 7 PM · Blue Bottle Coffee"
    static let readingProgress: Double = 0.62
}

// MARK: - Shared Sub-views
struct ProgressRacetrack: View {
    var progress: Double
    var body: some View {
        GeometryReader { geo in
            ZStack(alignment: .leading) {
                Capsule().fill(Color.secondary.opacity(0.2))
                Capsule()
                    .fill(Color.accentColor)
                    .frame(width: geo.size.width * progress)
            }
        }
        .frame(height: 10)
    }
}

// MARK: - Variation 1: Cozy
struct BookClubCozyView: View {
    var body: some View {
        NavigationStack {
            VStack(alignment: .leading, spacing: 20) {
                Text(BookClubSampleData.currentBook)
                    .font(.system(.title2, design: .serif, weight: .bold))
                Text(BookClubSampleData.nextMeeting)
                    .font(.subheadline)
                    .foregroundStyle(.secondary)
                ProgressRacetrack(progress: BookClubSampleData.readingProgress)
                Spacer()
            }
            .padding()
            .navigationTitle("Cozy Club")
        }
    }
}

// MARK: - Variation 2: Editorial
struct BookClubEditorialView: View {
    var body: some View {
        NavigationStack {
            List {
                Section("Now Reading") {
                    HStack {
                        RoundedRectangle(cornerRadius: 6)
                            .fill(Color.brown.opacity(0.3))
                            .frame(width: 50, height: 70)
                        VStack(alignment: .leading) {
                            Text(BookClubSampleData.currentBook)
                                .font(.headline)
                            Text("\(Int(BookClubSampleData.readingProgress * 100))% complete")
                                .font(.caption)
                                .foregroundStyle(.secondary)
                        }
                    }
                }
                Section("Standings") {
                    ForEach(Array(BookClubSampleData.members.enumerated()), id: \.offset) { i, name in
                        Label("\(i + 1). \(name)", systemImage: i == 0 ? "trophy.fill" : "person")
                    }
                }
            }
            .navigationTitle("Editorial")
        }
    }
}

// MARK: - Previews (each gets its own canvas tab — mirrors agent output)
#Preview("Cozy") {
    BookClubCozyView()
}

#Preview("Editorial") {
    BookClubEditorialView()
}

#Preview("Empty State") {
    NavigationStack {
        ContentUnavailableView(
            "No Club Yet",
            systemImage: "books.vertical",
            description: Text("Create or join a book club to get started.")
        )
        .navigationTitle("Book Club")
    }
}