import SwiftUI

struct ContentView: View {
    @EnvironmentObject private var app: AppModel

    var body: some View {
        VStack(spacing: 0) {
            NavigationSplitView {
                List(AppModel.Section.allCases, selection: $app.section) { item in
                    Label(item.rawValue, systemImage: item.icon).tag(item)
                }
                .listStyle(.sidebar)
                .navigationTitle("Tonuino Manager")
                .safeAreaInset(edge: .bottom) {
                    HStack(spacing: 8) {
                        Circle().fill(app.library.rootURL == nil ? Color.secondary : Color.green).frame(width: 8, height: 8)
                        Text(app.library.activeProfile.map { "Lokal · \($0.name)" } ?? (app.library.rootURL?.lastPathComponent ?? "Keine Bibliothek ausgewählt"))
                            .lineLimit(1).foregroundStyle(.secondary)
                    }
                    .font(.caption).padding()
                }
            } detail: {
                switch app.section {
                case .library: LibraryView()
                case .cards: CardsView()
                case .tonuino: TonuinoSettingsView()
                case .settings: SettingsView()
                }
            }
            .frame(maxWidth: .infinity, maxHeight: .infinity)

            HStack {
                Spacer(minLength: 0)
                Text(app.status)
                    .font(.caption)
                    .foregroundStyle(.secondary)
                    .lineLimit(1)
                    .truncationMode(.tail)
                    .frame(maxWidth: 520, alignment: .trailing)
            }
            .padding(.horizontal, 14)
            .padding(.vertical, 6)
            .frame(maxWidth: .infinity)
            .background(.regularMaterial)
            .overlay(alignment: .top) {
                Rectangle().fill(.primary.opacity(0.08)).frame(height: 1)
            }
        }
        .alert("Fehler", isPresented: $app.showError) {
            Button("OK", role: .cancel) { }
        } message: { Text(app.errorMessage ?? "Unbekannter Fehler") }
    }
}