import SwiftUI

struct EditHabitView: View {
    @Binding var isPresented: Bool
    @EnvironmentObject var authManager: AuthManager
    let habit: Habit
    let onSaved: () async -> Void

    @State private var name: String
    @State private var selectedIcon: String
    @State private var selectedColor: String
    @State private var frequency: HabitFrequency
    @State private var selectedWeekdays: Set<Int>
    @State private var intervalDays: String
    @State private var isLoading = false
    @State private var showArchiveConfirm = false

    let weekdayNames = ["Вс","Пн","Вт","Ср","Чт","Пт","Сб"]
    let icons = ["🔥", "💪", "🏃", "📚", "💧", "🧘", "🎯", "⭐️", "🌟", "✅",
                 "🏋️", "🚴", "🍎", "😴", "🧠", "🎨", "🎵", "💊", "🌿", "💰",
                 "✍️", "🧹", "🏊", "🚶", "🎮", "📝", "🌅", "🥗", "🧃", "🫁"]
    let colors = ["#0D9488", "#7c3aed", "#ff4757", "#ffa502", "#6366f1",
                  "#ec4899", "#14b8a6", "#f59e0b", "#10b981", "#3b82f6"]
    let frequencies: [(HabitFrequency, String, String)] = [
        (.daily, "Каждый день", "calendar"),
        (.weekly, "По дням недели", "calendar.badge.clock"),
        (.interval, "Каждые N дней", "repeat"),
        (.monthly, "Каждый месяц", "calendar.badge.plus")
    ]

    init(isPresented: Binding<Bool>, habit: Habit, onSaved: @escaping () async -> Void) {
        self._isPresented = isPresented
        self.habit = habit
        self.onSaved = onSaved
        self._name = State(initialValue: habit.name)
        self._selectedIcon = State(initialValue: habit.icon ?? "🔥")
        self._selectedColor = State(initialValue: habit.color ?? "#0D9488")
        self._frequency = State(initialValue: habit.frequency)
        self._selectedWeekdays = State(initialValue: Set(habit.targetDays ?? [1,2,3,4,5]))
        self._intervalDays = State(initialValue: String(habit.targetCount ?? 2))
    }

    var body: some View {
        ZStack {
            Color(hex: "0a0a1a").ignoresSafeArea()
            VStack(spacing: 0) {
                RoundedRectangle(cornerRadius: 3)
                    .fill(Color.white.opacity(0.2)).frame(width: 40, height: 4).padding(.top, 12)
                HStack {
                    Button("Отмена") { isPresented = false }.foregroundColor(Color(hex: "8888aa"))
                    Spacer()
                    Text("Редактировать привычку").font(.headline).foregroundColor(.white)
                    Spacer()
                    Button(action: save) {
                        if isLoading { ProgressView().tint(Color(hex: "0D9488")).scaleEffect(0.8) }
                        else { Text("Сохранить").foregroundColor(name.isEmpty ? Color(hex: "8888aa") : Color(hex: "0D9488")).fontWeight(.semibold) }
                    }.disabled(name.isEmpty || isLoading)
                }
                .padding(.horizontal, 20).padding(.vertical, 16)
                Divider().background(Color.white.opacity(0.1))
                ScrollView {
                    VStack(spacing: 20) {
                        // Preview
                        HStack(spacing: 16) {
                            ZStack {
                                Circle()
                                    .fill(Color(hex: String(selectedColor.dropFirst())).opacity(0.25))
                                    .frame(width: 56, height: 56)
                                Text(selectedIcon).font(.title2)
                            }
                            VStack(alignment: .leading, spacing: 4) {
                                Text(name.isEmpty ? "Название привычки" : name)
                                    .font(.callout.bold())
                                    .foregroundColor(name.isEmpty ? Color(hex: "8888aa") : .white)
                                Text(frequencies.first { $0.0 == frequency }?.1 ?? "")
                                    .font(.caption).foregroundColor(Color(hex: "8888aa"))
                            }
                            Spacer()
                        }
                        .padding(16)
                        .background(RoundedRectangle(cornerRadius: 16).fill(Color.white.opacity(0.05)))

                        // Name
                        VStack(alignment: .leading, spacing: 8) {
                            Label("Название", systemImage: "pencil").font(.caption).foregroundColor(Color(hex: "8888aa"))
                            TextField("Например: Читать 30 минут", text: $name)
                                .foregroundColor(.white).padding(14)
                                .background(RoundedRectangle(cornerRadius: 12).fill(Color.white.opacity(0.07)))
                        }

                        // Frequency
                        VStack(alignment: .leading, spacing: 8) {
                            Label("Периодичность", systemImage: "calendar").font(.caption).foregroundColor(Color(hex: "8888aa"))
                            VStack(spacing: 6) {
                                ForEach(frequencies, id: \.0) { f in
                                    Button(action: { frequency = f.0 }) {
                                        HStack {
                                            Image(systemName: f.2).foregroundColor(frequency == f.0 ? Color(hex: "0D9488") : Color(hex: "8888aa"))
                                            Text(f.1).foregroundColor(frequency == f.0 ? .white : Color(hex: "8888aa"))
                                            Spacer()
                                            if frequency == f.0 { Image(systemName: "checkmark").foregroundColor(Color(hex: "0D9488")) }
                                        }
                                        .padding(14)
                                        .background(RoundedRectangle(cornerRadius: 12).fill(frequency == f.0 ? Color(hex: "0D9488").opacity(0.15) : Color.white.opacity(0.05)))
                                    }
                                }
                            }
                            if frequency == .weekly {
                                HStack(spacing: 8) {
                                    ForEach(0..<7) { i in
                                        Button(action: {
                                            if selectedWeekdays.contains(i) { if selectedWeekdays.count > 1 { selectedWeekdays.remove(i) } }
                                            else { selectedWeekdays.insert(i) }
                                        }) {
                                            Text(weekdayNames[i])
                                                .font(.caption.bold())
                                                .foregroundColor(selectedWeekdays.contains(i) ? .black : .white)
                                                .frame(width: 32, height: 32)
                                                .background(Circle().fill(selectedWeekdays.contains(i) ? Color(hex: "0D9488") : Color.white.opacity(0.08)))
                                        }
                                    }
                                }
                            }
                            if frequency == .interval {
                                HStack {
                                    Text("Каждые").foregroundColor(Color(hex: "8888aa")).font(.callout)
                                    TextField("2", text: $intervalDays).keyboardType(.numberPad)
                                        .foregroundColor(.white)
                                        .frame(width: 50)
                                        .padding(10)
                                        .background(RoundedRectangle(cornerRadius: 8).fill(Color.white.opacity(0.07)))
                                    Text("дней").foregroundColor(Color(hex: "8888aa")).font(.callout)
                                }
                            }
                        }

                        // Icon picker
                        VStack(alignment: .leading, spacing: 8) {
                            Label("Иконка", systemImage: "face.smiling").font(.caption).foregroundColor(Color(hex: "8888aa"))
                            LazyVGrid(columns: Array(repeating: GridItem(.flexible()), count: 6), spacing: 8) {
                                ForEach(icons, id: \.self) { icon in
                                    Button(action: { selectedIcon = icon }) {
                                        Text(icon).font(.title3)
                                            .frame(width: 40, height: 40)
                                            .background(Circle().fill(selectedIcon == icon ? Color(hex: "0D9488").opacity(0.25) : Color.white.opacity(0.05)))
                                            .overlay(Circle().stroke(selectedIcon == icon ? Color(hex: "0D9488") : Color.clear, lineWidth: 2))
                                    }
                                }
                            }
                        }

                        // Color picker
                        VStack(alignment: .leading, spacing: 8) {
                            Label("Цвет", systemImage: "paintpalette").font(.caption).foregroundColor(Color(hex: "8888aa"))
                            HStack(spacing: 10) {
                                ForEach(colors, id: \.self) { color in
                                    Button(action: { selectedColor = color }) {
                                        Circle()
                                            .fill(Color(hex: String(color.dropFirst())))
                                            .frame(width: 32, height: 32)
                                            .overlay(Circle().stroke(.white, lineWidth: selectedColor == color ? 2 : 0))
                                            .scaleEffect(selectedColor == color ? 1.15 : 1.0)
                                            .animation(.easeInOut(duration: 0.15), value: selectedColor)
                                    }
                                }
                            }
                        }

                        // Archive / Restore button
                        Button(action: { showArchiveConfirm = true }) {
                            HStack {
                                Image(systemName: habit.isArchived == true ? "arrow.uturn.backward" : "archivebox")
                                Text(habit.isArchived == true ? "Восстановить" : "Архивировать")
                            }
                            .foregroundColor(habit.isArchived == true ? Color(hex: "0D9488") : Color(hex: "ff4757"))
                            .frame(maxWidth: .infinity)
                            .padding(14)
                            .background(RoundedRectangle(cornerRadius: 12).fill(Color.white.opacity(0.05)))
                        }
                    }.padding(20)
                }
            }
        }
        .confirmationDialog(
            habit.isArchived == true ? "Восстановить привычку?" : "Архивировать привычку?",
            isPresented: $showArchiveConfirm,
            titleVisibility: .visible
        ) {
            Button(habit.isArchived == true ? "Восстановить" : "Архивировать",
                   role: habit.isArchived == true ? .none : .destructive) {
                Task { await toggleArchive() }
            }
            Button("Отмена", role: .cancel) {}
        }
    }

    func save() {
        isLoading = true
        Task {
            var body: [String: Any] = [
                "name": name,
                "frequency": frequency.rawValue,
                "icon": selectedIcon,
                "color": selectedColor,
                "target_count": 1
            ]
            if frequency == .weekly {
                body["target_days"] = Array(selectedWeekdays).sorted()
            }
            if frequency == .interval {
                body["target_count"] = Int(intervalDays) ?? 2
            }
            if let reqBody = try? JSONSerialization.data(withJSONObject: body) {
                try? await APIService.shared.updateHabit(token: authManager.token, id: habit.id, body: reqBody)
            }
            await onSaved()
            await MainActor.run { isPresented = false }
        }
    }

    func toggleArchive() async {
        let params: [String: Any] = ["is_archived": !(habit.isArchived == true)]
        if let body = try? JSONSerialization.data(withJSONObject: params) {
            try? await APIService.shared.updateHabit(token: authManager.token, id: habit.id, body: body)
        }
        await onSaved()
        await MainActor.run { isPresented = false }
    }
}