//
//  SettingsView.swift
//  SportsTime
//

import SwiftUI

struct SettingsView: View {
    @Environment(\.colorScheme) private var colorScheme
    @State private var viewModel = SettingsViewModel()
    @State private var showResetConfirmation = false
    @State private var showPaywall = false
    @State private var showOnboardingPaywall = false

    var body: some View {
        List {
            // Subscription
            subscriptionSection

            // Appearance Mode (Light/Dark/System)
            appearanceSection

            // Theme Selection
            themeSection

            // UI Design Style
            designStyleSection

            // Sports Preferences
            sportsSection

            // Travel Preferences
            travelSection

            // About
            aboutSection

            // Reset
            resetSection

            #if DEBUG
            // Debug
            debugSection
            #endif
        }
        .scrollContentBackground(.hidden)
        .themedBackground()
        .alert("Reset Settings", isPresented: $showResetConfirmation) {
            Button("Cancel", role: .cancel) { }
            Button("Reset", role: .destructive) {
                viewModel.resetToDefaults()
            }
        } message: {
            Text("This will reset all settings to their default values.")
        }
        .sheet(isPresented: $showOnboardingPaywall) {
            OnboardingPaywallView(isPresented: $showOnboardingPaywall)
        }
    }

    // MARK: - Appearance Section

    private var appearanceSection: some View {
        Section {
            ForEach(AppearanceMode.allCases) { mode in
                Button {
                    withAnimation(.easeInOut(duration: 0.2)) {
                        AppearanceManager.shared.currentMode = mode
                    }
                } label: {
                    HStack(spacing: 12) {
                        // Icon
                        ZStack {
                            Circle()
                                .fill(Theme.warmOrange.opacity(0.15))
                                .frame(width: 32, height: 32)

                            Image(systemName: mode.iconName)
                                .font(.system(size: 16))
                                .foregroundStyle(Theme.warmOrange)
                        }

                        VStack(alignment: .leading, spacing: 2) {
                            Text(mode.displayName)
                                .font(.body)
                                .foregroundStyle(.primary)
                            Text(mode.description)
                                .font(.caption)
                                .foregroundStyle(.secondary)
                        }

                        Spacer()

                        if AppearanceManager.shared.currentMode == mode {
                            Image(systemName: "checkmark.circle.fill")
                                .foregroundStyle(Theme.warmOrange)
                                .font(.title3)
                        }
                    }
                    .contentShape(Rectangle())
                }
                .buttonStyle(.plain)
            }
        } header: {
            Text("Appearance")
        } footer: {
            Text("Choose light, dark, or follow your device settings.")
        }
        .listRowBackground(Theme.cardBackground(colorScheme))
    }

    // MARK: - Theme Section

    private var themeSection: some View {
        Section {
            ForEach(AppTheme.allCases) { theme in
                Button {
                    withAnimation(.easeInOut(duration: 0.2)) {
                        viewModel.selectedTheme = theme
                    }
                } label: {
                    HStack(spacing: 12) {
                        // Color preview circles
                        HStack(spacing: -6) {
                            ForEach(Array(theme.previewColors.enumerated()), id: \.offset) { _, color in
                                Circle()
                                    .fill(color)
                                    .frame(width: 24, height: 24)
                                    .overlay(
                                        Circle()
                                            .stroke(Color.primary.opacity(0.1), lineWidth: 1)
                                    )
                            }
                        }

                        VStack(alignment: .leading, spacing: 2) {
                            Text(theme.displayName)
                                .font(.body)
                                .foregroundStyle(.primary)
                            Text(theme.description)
                                .font(.caption)
                                .foregroundStyle(.secondary)
                        }

                        Spacer()

                        if viewModel.selectedTheme == theme {
                            Image(systemName: "checkmark.circle.fill")
                                .foregroundStyle(Theme.warmOrange)
                                .font(.title3)
                        }
                    }
                    .contentShape(Rectangle())
                }
                .buttonStyle(.plain)
            }
        } header: {
            Text("Theme")
        } footer: {
            Text("Choose a color scheme for the app.")
        }
        .listRowBackground(Theme.cardBackground(colorScheme))
    }

    // MARK: - Design Style Section

    private var designStyleSection: some View {
        Section {
            ForEach(UIDesignStyle.allCases) { style in
                Button {
                    withAnimation(.easeInOut(duration: 0.2)) {
                        DesignStyleManager.shared.setStyle(style)
                    }
                } label: {
                    HStack(spacing: 12) {
                        // Icon with accent color
                        ZStack {
                            Circle()
                                .fill(style.accentColor.opacity(0.15))
                                .frame(width: 36, height: 36)

                            Image(systemName: style.iconName)
                                .font(.system(size: 16))
                                .foregroundStyle(style.accentColor)
                        }

                        VStack(alignment: .leading, spacing: 2) {
                            Text(style.rawValue)
                                .font(.body)
                                .foregroundStyle(.primary)
                            Text(style.description)
                                .font(.caption)
                                .foregroundStyle(.secondary)
                                .lineLimit(1)
                        }

                        Spacer()

                        if DesignStyleManager.shared.currentStyle == style {
                            Image(systemName: "checkmark.circle.fill")
                                .foregroundStyle(style.accentColor)
                                .font(.title3)
                        }
                    }
                    .contentShape(Rectangle())
                }
                .buttonStyle(.plain)
            }
        } header: {
            Text("Home Screen Style")
        } footer: {
            Text("Choose a visual aesthetic for the home screen.")
        }
        .listRowBackground(Theme.cardBackground(colorScheme))
    }

    // MARK: - Sports Section

    private var sportsSection: some View {
        Section {
            ForEach(Sport.supported) { sport in
                Toggle(isOn: Binding(
                    get: { viewModel.selectedSports.contains(sport) },
                    set: { _ in viewModel.toggleSport(sport) }
                )) {
                    Label {
                        Text(sport.displayName)
                    } icon: {
                        Image(systemName: sport.iconName)
                            .foregroundStyle(sportColor(for: sport))
                    }
                }
            }
        } header: {
            Text("Favorite Sports")
        } footer: {
            Text("Selected sports will be shown by default in schedules and trip planning.")
        }
        .listRowBackground(Theme.cardBackground(colorScheme))
    }

    // MARK: - Travel Section

    private var travelSection: some View {
        Section {
            VStack(alignment: .leading, spacing: 8) {
                HStack {
                    Text("Max Driving Per Day")
                    Spacer()
                    Text("\(viewModel.maxDrivingHoursPerDay) hours")
                        .foregroundStyle(.secondary)
                }
                Slider(
                    value: Binding(
                        get: { Double(viewModel.maxDrivingHoursPerDay) },
                        set: { viewModel.maxDrivingHoursPerDay = Int($0) }
                    ),
                    in: 2...12,
                    step: 1
                )
            }

        } header: {
            Text("Travel Preferences")
        } footer: {
            Text("Trips will be optimized to keep daily driving within this limit.")
        }
        .listRowBackground(Theme.cardBackground(colorScheme))
    }

    // MARK: - About Section

    private var aboutSection: some View {
        Section {
            HStack {
                Text("Version")
                Spacer()
                Text("\(viewModel.appVersion) (\(viewModel.buildNumber))")
                    .foregroundStyle(.secondary)
            }

            Link(destination: URL(string: "https://88oakapps.com/privacy")!) {
                Label("Privacy Policy", systemImage: "hand.raised")
            }

            Link(destination: URL(string: "https://88oakapps.com/terms")!) {
                Label("Terms of Service", systemImage: "doc.text")
            }

            Link(destination: URL(string: "mailto:support@88oakapps.com")!) {
                Label("Contact Support", systemImage: "envelope")
            }
        } header: {
            Text("About")
        }
        .listRowBackground(Theme.cardBackground(colorScheme))
    }

    // MARK: - Reset Section

    private var resetSection: some View {
        Section {
            Button(role: .destructive) {
                showResetConfirmation = true
            } label: {
                Label("Reset to Defaults", systemImage: "arrow.counterclockwise")
            }
        }
        .listRowBackground(Theme.cardBackground(colorScheme))
    }

    // MARK: - Debug Section

    #if DEBUG
    private var debugSection: some View {
        Section {
            Toggle(isOn: Binding(
                get: { StoreManager.shared.debugProOverride },
                set: { StoreManager.shared.debugProOverride = $0 }
            )) {
                Label("Override Pro Status", systemImage: "star.fill")
            }

            Button {
                showOnboardingPaywall = true
            } label: {
                Label("Show Onboarding Flow", systemImage: "play.circle")
            }

            Button {
                UserDefaults.standard.removeObject(forKey: "hasSeenOnboardingPaywall")
            } label: {
                Label("Reset Onboarding Flag", systemImage: "arrow.counterclockwise")
            }
        } header: {
            Text("Debug")
        } footer: {
            Text("These options are only visible in debug builds.")
        }
        .listRowBackground(Theme.cardBackground(colorScheme))
    }
    #endif

    // MARK: - Subscription Section

    private var subscriptionSection: some View {
        Section {
            if StoreManager.shared.isPro {
                // Pro user - show manage option
                HStack {
                    Label {
                        VStack(alignment: .leading, spacing: 4) {
                            Text("SportsTime Pro")
                                .foregroundStyle(Theme.textPrimary(colorScheme))
                            Text("Active subscription")
                                .font(.caption)
                                .foregroundStyle(.green)
                        }
                    } icon: {
                        Image(systemName: "star.fill")
                            .foregroundStyle(Theme.warmOrange)
                    }

                    Spacer()

                    Image(systemName: "checkmark.circle.fill")
                        .foregroundStyle(.green)
                }

                Button {
                    if let url = URL(string: "https://apps.apple.com/account/subscriptions") {
                        UIApplication.shared.open(url)
                    }
                } label: {
                    Label("Manage Subscription", systemImage: "gear")
                }
            } else {
                // Free user - show upgrade option
                Button {
                    showPaywall = true
                } label: {
                    HStack {
                        Label {
                            VStack(alignment: .leading, spacing: 4) {
                                Text("Upgrade to Pro")
                                    .foregroundStyle(Theme.textPrimary(colorScheme))
                                Text("Unlimited trips, PDF export, progress tracking")
                                    .font(.caption)
                                    .foregroundStyle(Theme.textSecondary(colorScheme))
                            }
                        } icon: {
                            Image(systemName: "star.fill")
                                .foregroundStyle(Theme.warmOrange)
                        }

                        Spacer()

                        Image(systemName: "chevron.right")
                            .foregroundStyle(Theme.textMuted(colorScheme))
                    }
                }
                .buttonStyle(.plain)

                Button {
                    Task {
                        await StoreManager.shared.restorePurchases()
                    }
                } label: {
                    Label("Restore Purchases", systemImage: "arrow.clockwise")
                }
            }
        } header: {
            Text("Subscription")
        }
        .listRowBackground(Theme.cardBackground(colorScheme))
        .sheet(isPresented: $showPaywall) {
            PaywallView()
        }
    }

    // MARK: - Helpers

    private func sportColor(for sport: Sport) -> Color {
        sport.themeColor
    }
}

#Preview {
    NavigationStack {
        SettingsView()
    }
}