import SwiftUI

struct MainTabView: View {
    @State private var selectedTab: AppTab = .home
    @StateObject private var notificationVM = NotificationsViewModel()

    var body: some View {
        TabView(selection: $selectedTab) {
            Group {
                TrainingPlanView()
                    .tag(AppTab.home)
                    .tabItem {
                        Label(AppTab.home.title, systemImage: AppTab.home.icon)
                    }

                ChallengesView()
                    .tag(AppTab.challenges)
                    .tabItem {
                        Label(AppTab.challenges.title, systemImage: AppTab.challenges.icon)
                    }

                ClubsView()
                    .tag(AppTab.clubs)
                    .tabItem {
                        Label(AppTab.clubs.title, systemImage: AppTab.clubs.icon)
                    }

                NotificationsView(viewModel: notificationVM)
                    .tag(AppTab.notifications)
                    .tabItem {
                        Label(AppTab.notifications.title, systemImage: AppTab.notifications.icon)
                    }
                    .badge(notificationVM.badgeCount)

                SettingsView()
                    .tag(AppTab.profile)
                    .tabItem {
                        Label(AppTab.profile.title, systemImage: AppTab.profile.icon)
                    }
            }
        }
        .onAppear {
            Task {
                await notificationVM.fetchUnreadCount()
            }
        }
        .onChange(of: selectedTab) { _, newTab in
            if newTab == .notifications {
                Task {
                    await notificationVM.fetchNotifications()
                    await notificationVM.fetchUnreadCount()
                }
            }
        }
    }
}

enum AppTab: String, CaseIterable {
    case home
    case challenges
    case clubs
    case notifications
    case profile

    var title: String {
        switch self {
        case .home: return "Home"
        case .challenges: return "Challenges"
        case .clubs: return "Clubs"
        case .notifications: return "Notifications"
        case .profile: return "Profile"
        }
    }

    var icon: String {
        switch self {
        case .home: return "house.fill"
        case .challenges: return "flag.fill"
        case .clubs: return "person.3.fill"
        case .notifications: return "bell.fill"
        case .profile: return "person.circle"
        }
    }
}

#Preview {
    MainTabView()
}