import SwiftUI
import MapKit

struct LeadLocationSection: View {
    let name: String
    let address: LeadAddress
    var locationService: any CustomerLocationService = AppleMapsCustomerLocationService()
    @State private var coordinate: CLLocationCoordinate2D?
    @State private var position: MapCameraPosition = .automatic
    @State private var errorMessage: LocalizedStringResource?
    @State private var retryID = 0

    static let mapHeight: CGFloat = 328

    private var addressText: String {
        [address.street, "\(address.postalCode) \(address.city)"]
            .compactMap { $0 }
            .joined(separator: ", ")
    }

    private var mapsURL: URL? {
        var components = URLComponents(string: "https://maps.apple.com/")
        components?.queryItems = [URLQueryItem(name: "q", value: addressText)]
        return components?.url
    }

    var body: some View {
        VStack(alignment: .leading, spacing: 8) {
            LeadSectionHeading(title: "STANDORT")
            ZStack {
                LeadDetailStyle.card
                if let coordinate {
                    Map(position: $position) {
                        Marker(name, coordinate: coordinate)
                            .tint(LeadDetailStyle.blue)
                    }
                    .mapStyle(.standard(pointsOfInterest: .excludingAll))
                    .accessibilityLabel("Standort von \(name), \(addressText)")
                } else if let errorMessage {
                    ContentUnavailableView {
                        Label("Standort nicht verfügbar", systemImage: "mappin.slash")
                    } description: {
                        Text(errorMessage)
                    } actions: {
                        Button("Erneut versuchen") { retryID += 1 }
                    }
                } else {
                    ProgressView("Standort wird geladen")
                }
            }
            .safeAreaInset(edge: .bottom, spacing: 0) {
                if let mapsURL {
                    Link(destination: mapsURL) {
                        Label("In Apple Maps öffnen", systemImage: "map")
                            .font(.subheadline.weight(.semibold))
                            .frame(maxWidth: .infinity, minHeight: 48)
                            .foregroundStyle(.white)
                            .background(LeadDetailStyle.blue)
                    }
                    .buttonStyle(.plain)
                }
            }
            .frame(maxWidth: .infinity)
            .frame(height: Self.mapHeight)
            .clipShape(.rect(cornerRadius: 12))
        }
        .task(id: addressText + "#\(retryID)") {
            coordinate = nil
            errorMessage = nil
            do {
                let result = try await locationService.coordinate(for: addressText)
                try Task.checkCancellation()
                position = .region(MKCoordinateRegion(
                    center: result, latitudinalMeters: 800, longitudinalMeters: 800
                ))
                coordinate = result
            } catch is CancellationError {
            } catch {
                guard !Task.isCancelled else { return }
                if error is CustomerLocationError {
                    errorMessage = "Für diese Anschrift wurde kein Standort gefunden."
                } else if let networkError = error as? URLError,
                          [.notConnectedToInternet, .networkConnectionLost, .timedOut].contains(networkError.code) {
                    errorMessage = "Keine Verbindung zu Apple Maps. Bitte prüfe deine Internetverbindung und versuche es erneut."
                } else {
                    errorMessage = "Apple Maps konnte den Standort gerade nicht ermitteln. Bitte versuche es erneut."
                }
            }
        }
    }
}