// SettingsView.swift
// Jarvis — settings hub: Notifications, Connectivity, and server info.

import SwiftUI
import SwiftData

struct SettingsView: View {
    @EnvironmentObject var settings: ServerSettings
    @Environment(\.dismiss) private var dismiss
    @Environment(\.modelContext) private var modelContext
    @AppStorage("appearanceMode") private var appearanceMode: AppearanceMode = .dark
    @Query private var cachedStories: [CachedStory]
    @Query private var cachedArticles: [CachedArticle]
    @State private var showClearConfirm = false

    var body: some View {
        NavigationStack {
            ZStack {
                Palette.background.ignoresSafeArea()
                ScrollView {
                    VStack(alignment: .leading, spacing: 26) {
                        header

                        group("APPEARANCE") {
                            appearancePicker
                        }

                        group("GENERAL") {
                            NavigationLink { NotificationsView() } label: {
                                row(icon: "bell.badge", title: "Notifications",
                                    subtitle: "Briefings & breaking alerts")
                            }
                            divider
                            NavigationLink { ConnectivityView() } label: {
                                row(icon: "globe", title: "Connectivity",
                                    subtitle: "Server address & Tailscale remote")
                            }
                        }

                        group("PLATFORM") {
                            row(icon: "server.rack", title: settings.host ?? "Not configured",
                                subtitle: "Connected server", chevron: false)
                        }

                        group("STORAGE") {
                            Button { showClearConfirm = true } label: {
                                row(icon: "trash", title: "Clear offline cache",
                                    subtitle: "\(cachedStories.count) stories · \(cachedArticles.count) articles · keeps saved",
                                    chevron: false, tint: Color(hex: "C25555"))
                            }
                        }
                    }
                    .padding(.horizontal, 20)
                    .padding(.vertical, 12)
                }
            }
            .navigationBarHidden(true)
        }
        .presentationDragIndicator(.visible)
        .confirmationDialog("Clear offline cache?", isPresented: $showClearConfirm, titleVisibility: .visible) {
            Button("Clear cache", role: .destructive) { CacheMaintenance.clear(modelContext) }
            Button("Cancel", role: .cancel) {}
        } message: {
            Text("Removes cached stories, articles, and read/seen history. Your saved stories are kept.")
        }
    }

    private var appearancePicker: some View {
        HStack(spacing: 14) {
            Image(systemName: "circle.lefthalf.filled")
                .font(.system(size: 18))
                .foregroundStyle(Palette.secondaryText)
                .frame(width: 26)
            Text("Theme")
                .font(.system(size: 16, weight: .heavy))
                .foregroundStyle(Palette.primaryText)
            Spacer()
            HStack(spacing: 0) {
                ForEach(AppearanceMode.allCases, id: \.self) { mode in
                    Button {
                        appearanceMode = mode
                    } label: {
                        Text(mode.label)
                            .font(.system(size: 12, weight: .bold))
                            .foregroundStyle(appearanceMode == mode ? .black : Palette.secondaryText)
                            .padding(.horizontal, 12)
                            .frame(height: 30)
                            .background(appearanceMode == mode ? Palette.orange : Color.clear)
                            .clipShape(Capsule())
                    }
                    .buttonStyle(.plain)
                }
            }
            .background(Palette.surface2)
            .clipShape(Capsule())
            .overlay(Capsule().stroke(Palette.surface2, lineWidth: 0.5))
        }
        .padding(.horizontal, 14).padding(.vertical, 14)
        .contentShape(Rectangle())
    }

    private var header: some View {
        HStack {
            Text("Settings").font(.system(size: 22, weight: .heavy)).foregroundStyle(Palette.primaryText)
            Spacer()
            Button { dismiss() } label: {
                Image(systemName: "xmark").font(.system(size: 15, weight: .bold))
                    .foregroundStyle(Palette.secondaryText).frame(width: 44, height: 44)
            }
        }
        .padding(.top, 8)
    }

    private func group<C: View>(_ label: String, @ViewBuilder _ content: () -> C) -> some View {
        VStack(alignment: .leading, spacing: 10) {
            Text(label).font(.system(size: 11, weight: .bold, design: .monospaced))
                .kerning(0.8).foregroundStyle(Palette.tertiaryText)
            VStack(spacing: 0) { content() }
                .background(Palette.surface)
                .clipShape(RoundedRectangle(cornerRadius: 14))
        }
    }

    private func row(icon: String, title: String, subtitle: String,
                     chevron: Bool = true, tint: Color? = nil) -> some View {
        let resolvedTint = tint ?? Palette.primaryText
        return HStack(spacing: 14) {
            Image(systemName: icon).font(.system(size: 18))
                .foregroundStyle(tint == nil ? Palette.secondaryText : resolvedTint).frame(width: 26)
            VStack(alignment: .leading, spacing: 2) {
                Text(title).font(.system(size: 16, weight: .heavy)).foregroundStyle(resolvedTint).lineLimit(1)
                Text(subtitle).font(.system(size: 12)).foregroundStyle(Palette.secondaryText).lineLimit(1)
            }
            Spacer()
            if chevron {
                Image(systemName: "chevron.right").font(.system(size: 13, weight: .bold))
                    .foregroundStyle(Palette.tertiaryText)
            }
        }
        .padding(.horizontal, 14).padding(.vertical, 14).frame(minHeight: 44)
        .contentShape(Rectangle())
    }

    private var divider: some View {
        Rectangle().fill(Palette.surface2).frame(height: 1).padding(.leading, 54)
    }
}