import SwiftUI

struct ClubsView: View {
    @StateObject private var viewModel = ClubViewModel()
    @State private var showingCreateSheet = false
    @State private var selectedTab: ClubTab = .discover

    enum ClubTab: String, CaseIterable {
        case discover, myClubs
    }

    var body: some View {
        NavigationView {
            Group {
                if viewModel.isLoading && viewModel.clubs.isEmpty {
                    loadingView
                } else if currentClubs.isEmpty {
                    emptyStateView
                } else {
                    clubListView
                }
            }
            .navigationTitle("Clubs")
            .navigationBarTitleDisplayMode(.inline)
            .toolbar {
                ToolbarItem(placement: .navigationBarTrailing) {
                    Button {
                        showingCreateSheet = true
                    } label: {
                        Image(systemName: "plus")
                    }
                }
            }
            .sheet(isPresented: $showingCreateSheet) {
                CreateClubSheet()
            }
        }
        .onAppear {
            Task {
                await viewModel.fetchClubs()
            }
        }
    }

    private var currentClubs: [Club] {
        switch selectedTab {
        case .discover: return viewModel.publicClubs
        case .myClubs: return viewModel.userClubs
        }
    }

    private var clubListView: some View {
        List {
            Picker("Clubs", selection: $selectedTab) {
                ForEach(ClubTab.allCases, id: \.self) { tab in
                    Text(tab.rawValue.capitalized).tag(tab)
                }
            }
            .pickerStyle(.segmented)
            .padding(.top, 8)

            Section(currentSectionTitle) {
                ForEach(currentClubs) { club in
                    NavigationLink(destination: ClubDetailView(club: club)) {
                        ClubRowView(club: club)
                    }
                }
            }
        }
        .listStyle(.insetGrouped)
        .refreshable {
            await viewModel.fetchClubs()
        }
    }

    private var currentSectionTitle: String {
        switch selectedTab {
        case .discover: return "Discover Clubs"
        case .myClubs: return "My Clubs"
        }
    }

    private var loadingView: some View {
        VStack(spacing: 16) {
            ProgressView()
            Text("Loading Clubs...")
                .font(.subheadline)
                .foregroundColor(.secondary)
        }
        .padding(.vertical, 60)
    }

    private var emptyStateView: some View {
        VStack(spacing: 16) {
            Image(systemName: "person.3.fill")
                .font(.system(size: 64))
                .foregroundColor(.secondary)
            Text("No \(selectedTab.rawValue) Clubs")
                .font(.title2)
                .fontWeight(.semibold)
            Text(selectedTab == .discover
                 ? "Find running and fitness clubs in your area."
                 : "Join or create a club to get started.")
                .font(.subheadline)
                .foregroundColor(.secondary)
                .multilineTextAlignment(.center)
                .padding(.horizontal, 32)
        }
        .padding(.vertical, 60)
    }
}

struct CreateClubSheet: View {
    @Environment(\.dismiss) var dismiss
    @State private var name = ""
    @State private var description = ""
    @State private var clubType: ClubType = .running
    @State private var privacy: ClubPrivacy = .publicPrivacy
    @State private var location = ""
    @State private var maxMembers = ""
    @State private var rules = ""

    var body: some View {
        NavigationView {
            Form {
                Section("Club Details") {
                    TextField("Club Name", text: $name)
                    TextField("Description", text: $description)
                    TextField("Location", text: $location)
                }

                Section("Type & Privacy") {
                    Picker("Club Type", selection: $clubType) {
                        ForEach(ClubType.allCases, id: \.self) { type in
                            Text(type.displayName).tag(type)
                        }
                    }
                    Picker("Privacy", selection: $privacy) {
                        ForEach(ClubPrivacy.allCases, id: \.self) { priv in
                            Text(priv.displayName).tag(priv)
                        }
                    }
                }

                Section("Optional") {
                    TextField("Max Members", text: $maxMembers)
                        .keyboardType(.numberPad)
                    TextField("Rules", text: $rules)
                }
            }
            .navigationTitle("Create Club")
            .navigationBarTitleDisplayMode(.inline)
            .toolbar {
                ToolbarItem(placement: .navigationBarLeading) {
                    Button("Cancel") { dismiss() }
                }
                ToolbarItem(placement: .navigationBarTrailing) {
                    Button("Create") {
                        let request = CreateClubRequest(
                            name: name,
                            description: description,
                            clubType: clubType,
                            privacy: privacy,
                            location: location,
                            latitude: nil,
                            longitude: nil,
                            maxMembers: Int(maxMembers),
                            rules: rules.isEmpty ? nil : rules
                        )
                        dismiss()
                    }
                    .disabled(name.isEmpty || location.isEmpty)
                }
            }
        }
    }
}

struct ClubRowView: View {
    let club: Club

    var body: some View {
        HStack(spacing: 12) {
            Image(systemName: club.clubType.icon)
                .font(.system(size: 24))
                .foregroundColor(club.clubType.color)
                .frame(width: 44, height: 44)
                .background(club.clubType.color.opacity(0.15))
                .cornerRadius(10)

            VStack(alignment: .leading, spacing: 4) {
                Text(club.name)
                    .font(.headline)
                Text("\(club.location) \u2022 \(club.privacy.displayName)")
                    .font(.subheadline)
                    .foregroundColor(.secondary)
                HStack(spacing: 8) {
                    Text("\(club.memberCount) members")
                        .font(.caption)
                        .foregroundColor(.secondary)
                    if let spots = club.availableSpots, spots > 0 {
                        Text("\(spots) spots left")
                            .font(.caption2)
                            .foregroundColor(.green)
                    }
                }
            }

            Spacer()

            switch club.membershipStatus {
            case .active:
                Image(systemName: "checkmark.circle.fill")
                    .foregroundColor(.green)
            case .pending:
                Image(systemName: "clock.fill")
                    .foregroundColor(.orange)
            case .invited:
                Image(systemName: "mail.fill")
                    .foregroundColor(.blue)
            case .left:
                Image(systemName: "circle")
                    .foregroundColor(.secondary)
            }
        }
        .padding(.vertical, 4)
    }
}

#Preview {
    ClubsView()
}