// Views/Dashboard/NotificationsView.swift
import SwiftUI
import SwiftData
import MessageUI

// MARK: - Notifications Inbox
// Shows the most recent notifications fetched during polling.
// Notifications are already marked read on the server by pollNotifications().

struct NotificationsView: View {

    @EnvironmentObject private var sync: SyncManager

    var body: some View {
        Group {
            if sync.recentNotifications.isEmpty {
                if !sync.isOnline {
                    ContentUnavailableView(
                        "Offline",
                        systemImage: "wifi.slash",
                        description: Text("Notifications are delivered when you go online.")
                    )
                } else {
                    ContentUnavailableView(
                        "No Notifications",
                        systemImage: "bell.slash",
                        description: Text("You\'re all caught up.")
                    )
                }
            } else {
                List(sync.recentNotifications) { notif in
                    VStack(alignment: .leading, spacing: 6) {
                        HStack(alignment: .top) {
                            Image(systemName: iconName(for: notif.eventType))
                                .foregroundStyle(iconColor(for: notif.eventType))
                                .frame(width: 24)
                            VStack(alignment: .leading, spacing: 2) {
                                Text(notif.title)
                                    .font(.callout.bold())
                                    .lineLimit(2)
                                Text(notif.body)
                                    .font(.caption)
                                    .foregroundStyle(.secondary)
                                    .lineLimit(3)
                            }
                        }
                        if let date = SyncManager.isoFormatter.date(from: notif.createdAt) {
                            Text(date.formatted(.relative(presentation: .named)))
                                .font(.caption2)
                                .foregroundStyle(.tertiary)
                        }
                    }
                    .padding(.vertical, 4)
                }
            }
        }
        .navigationTitle("Notifications")
        .navigationBarTitleDisplayMode(.large)
        .onAppear {
            sync.markNotificationsViewed()
        }
        .refreshable {
            await sync.pollNotifications()
            sync.markNotificationsViewed()
        }
    }

    private func iconName(for eventType: String?) -> String {
        switch eventType {
        case "inspection_completed": return "checkmark.circle.fill"
        case "issue_flagged":        return "exclamationmark.triangle.fill"
        case "issue_resolved":       return "checkmark.seal.fill"
        case "sla_alert":            return "clock.badge.exclamationmark"
        case "follow_up_required":   return "exclamationmark.arrow.circlepath"
        default:                     return "bell.fill"
        }
    }

    private func iconColor(for eventType: String?) -> Color {
        switch eventType {
        case "inspection_completed": return .green
        case "issue_flagged":        return .orange
        case "issue_resolved":       return .green
        case "sla_alert":            return .red
        case "follow_up_required":   return .orange
        default:                     return .blue
        }
    }
}