// NotificationsView.swift
// Jarvis — notification preferences: breaking alerts + morning/evening briefings
// with weather.

import SwiftUI

struct NotificationsView: View {
    @EnvironmentObject var manager: NotificationManager
    @StateObject private var settings = NotificationSettings.shared
    @Environment(\.dismiss) private var dismiss

    private var authorized: Bool {
        manager.authStatus == .authorized || manager.authStatus == .provisional
    }

    var body: some View {
        ZStack {
            Color.black.ignoresSafeArea()
            ScrollView {
                VStack(alignment: .leading, spacing: 24) {
                    header
                    if !authorized { permissionCard }
                    alertsSection
                    briefingSection(title: "MORNING BRIEFING", icon: "sunrise",
                                    on: $settings.morningEnabled,
                                    hour: $settings.morningHour, minute: $settings.morningMinute)
                    briefingSection(title: "EVENING BRIEFING", icon: "sunset",
                                    on: $settings.eveningEnabled,
                                    hour: $settings.eveningHour, minute: $settings.eveningMinute)
                    weatherSection
                    testButton
                }
                .padding(.horizontal, 20).padding(.vertical, 12)
            }
        }
        .navigationBarBackButtonHidden(false)
        .task { await manager.refreshAuthStatus() }
        .onChange(of: settings.morningEnabled) { _, _ in apply() }
        .onChange(of: settings.eveningEnabled) { _, _ in apply() }
        .onChange(of: settings.breakingEnabled) { _, _ in apply() }
        .onChange(of: settings.weatherEnabled) { _, _ in apply() }
    }

    private func apply() { Task { await manager.applySettings() } }

    // MARK: - Header

    private var header: some View {
        Text("Notifications").font(.system(size: 22, weight: .heavy)).foregroundStyle(.white)
            .padding(.top, 4)
    }

    private var permissionCard: some View {
        VStack(alignment: .leading, spacing: 12) {
            Text("Jarvis needs permission to send briefings and breaking alerts.")
                .font(.system(size: 14)).foregroundStyle(Color(hex: "BBBBBB"))
                .fixedSize(horizontal: false, vertical: true)
            Button {
                Task { await manager.requestAuthorization() }
            } label: {
                Text("Enable notifications")
                    .font(.system(size: 15, weight: .bold)).foregroundStyle(.black)
                    .frame(maxWidth: .infinity).frame(height: 48)
                    .background(Palette.orange).clipShape(RoundedRectangle(cornerRadius: 12))
            }
        }
        .padding(16).background(Palette.surface).clipShape(RoundedRectangle(cornerRadius: 14))
    }

    // MARK: - Alerts

    private var alertsSection: some View {
        section("ALERTS") {
            toggleRow(icon: "bolt.fill", title: "Breaking & new stories",
                      subtitle: "Notify when a high-signal story breaks",
                      isOn: $settings.breakingEnabled)
            if settings.breakingEnabled {
                divider
                HStack(spacing: 14) {
                    Image(systemName: "dial.medium").font(.system(size: 18))
                        .foregroundStyle(Color(hex: "999999")).frame(width: 26)
                    Text("Only above signal").font(.system(size: 15, weight: .bold)).foregroundStyle(.white)
                    Spacer()
                    Stepper(value: $settings.breakingMinSignal, in: 0...100, step: 5) {}
                        .labelsHidden().fixedSize()
                    Text("\(settings.breakingMinSignal)")
                        .font(.system(size: 15, weight: .bold, design: .monospaced))
                        .foregroundStyle(Palette.orange).frame(width: 34, alignment: .trailing)
                }
                .padding(.horizontal, 14).padding(.vertical, 12)
            }
        }
    }

    // MARK: - Briefings

    private func briefingSection(title: String, icon: String, on: Binding<Bool>,
                                 hour: Binding<Int>, minute: Binding<Int>) -> some View {
        section(title) {
            toggleRow(icon: icon, title: "Daily briefing",
                      subtitle: "Weather + top stories to watch", isOn: on)
            if on.wrappedValue {
                divider
                HStack(spacing: 14) {
                    Image(systemName: "clock").font(.system(size: 18))
                        .foregroundStyle(Color(hex: "999999")).frame(width: 26)
                    Text("Time").font(.system(size: 15, weight: .bold)).foregroundStyle(.white)
                    Spacer()
                    DatePicker("", selection: timeBinding(hour: hour, minute: minute),
                               displayedComponents: .hourAndMinute)
                        .labelsHidden()
                        .onChange(of: hour.wrappedValue) { _, _ in apply() }
                        .onChange(of: minute.wrappedValue) { _, _ in apply() }
                }
                .padding(.horizontal, 14).padding(.vertical, 10)
            }
        }
    }

    private func timeBinding(hour: Binding<Int>, minute: Binding<Int>) -> Binding<Date> {
        Binding(
            get: {
                Calendar.current.date(from: DateComponents(hour: hour.wrappedValue,
                                                           minute: minute.wrappedValue)) ?? Date()
            },
            set: { newDate in
                let c = Calendar.current.dateComponents([.hour, .minute], from: newDate)
                hour.wrappedValue = c.hour ?? hour.wrappedValue
                minute.wrappedValue = c.minute ?? minute.wrappedValue
            }
        )
    }

    // MARK: - Weather

    private var weatherSection: some View {
        section("WEATHER") {
            toggleRow(icon: "cloud.sun", title: "Include weather",
                      subtitle: "Today's outlook and rain in your briefing",
                      isOn: $settings.weatherEnabled)
            if settings.weatherEnabled {
                divider
                HStack(spacing: 14) {
                    Image(systemName: "mappin.and.ellipse").font(.system(size: 18))
                        .foregroundStyle(Color(hex: "999999")).frame(width: 26)
                    VStack(alignment: .leading, spacing: 3) {
                        Text("Location").font(.system(size: 12)).foregroundStyle(Color(hex: "888888"))
                        TextField("", text: $settings.locationName,
                                  prompt: Text("Kampala").foregroundColor(Color(hex: "444444")))
                            .font(.system(size: 16, weight: .regular))
                            .foregroundStyle(.white)
                            .autocorrectionDisabled()
                            .onSubmit { resolveLocation() }
                        if let place = settings.resolvedPlace {
                            Text(place).font(.system(size: 11, design: .monospaced))
                                .foregroundStyle(Color(hex: "33C25E"))
                        }
                    }
                    Spacer()
                    Button { resolveLocation() } label: {
                        Text("Set").font(.system(size: 13, weight: .bold)).foregroundStyle(.black)
                            .padding(.horizontal, 12).frame(height: 32)
                            .background(Palette.orange).clipShape(Capsule())
                    }
                }
                .padding(.horizontal, 14).padding(.vertical, 12)
            }
        }
    }

    private func resolveLocation() {
        Task {
            settings.latitude = nil; settings.longitude = nil; settings.resolvedPlace = nil
            await manager.applySettings()   // triggers geocode + reschedule
        }
    }

    // MARK: - Test

    private var testButton: some View {
        Button { Task { await manager.sendTestBriefing() } } label: {
            Text("Send a test briefing")
                .font(.system(size: 15, weight: .bold)).foregroundStyle(.white)
                .frame(maxWidth: .infinity).frame(height: 50)
                .background(Palette.surface2).clipShape(RoundedRectangle(cornerRadius: 14))
        }
        .disabled(!authorized)
        .opacity(authorized ? 1 : 0.5)
    }

    // MARK: - Building blocks

    private func section<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(Color(hex: "555555"))
            VStack(spacing: 0) { content() }
                .background(Palette.surface).clipShape(RoundedRectangle(cornerRadius: 14))
        }
    }

    private func toggleRow(icon: String, title: String, subtitle: String, isOn: Binding<Bool>) -> some View {
        HStack(spacing: 14) {
            Image(systemName: icon).font(.system(size: 18)).foregroundStyle(Color(hex: "999999")).frame(width: 26)
            Toggle(isOn: isOn) {
                VStack(alignment: .leading, spacing: 3) {
                    Text(title).font(.system(size: 16, weight: .heavy)).foregroundStyle(.white)
                    Text(subtitle).font(.system(size: 12)).foregroundStyle(Color(hex: "888888"))
                        .fixedSize(horizontal: false, vertical: true)
                }
            }
            .tint(Palette.orange)
        }
        .padding(.horizontal, 14).padding(.vertical, 14)
    }

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